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1

Advanced steel reheat furnace  

SciTech Connect

Energy and Environmental Research Corp. (EER) under a contract from the Department of Energy is pursuing the development and demonstration of an Advanced Steel Reheating Furnace. This paper reports the results of Phase 1, Research, which has evaluated an advanced furnace concept incorporating two proven and commercialized technologies previously applied to other high temperature combustion applications: EER`s gas reburn technology (GR) for post combustion NOx control; and Air Product`s oxy-fuel enrichment air (OEA) for improved flame heat transfer in the heating zones of the furnace. The combined technologies feature greater production throughput with associated furnace efficiency improvements; lowered NOx emissions; and better control over the furnace atmosphere, whether oxidizing or reducing, leading to better control over surface finish.

Moyeda, D.; Sheldon, M.; Koppang, R. [Energy and Environmental Research Corp., Irvine, CA (United States); Lanyi, M.; Li, X.; Eleazer, B. [Air Products and Chemicals, Inc., Allentown, PA (United States)

1997-10-01

2

Advanced steel reheat furnaces: Research and development. Final report  

SciTech Connect

The purpose of this report is to present the results of two phases of a three-phase project to develop and evaluate an Advanced Steel Reheat Furnace (SSRF) concept which incorporates two proven and commercialized technologies, oxy-fuel enriched air (OEA) combustion and gas reburning (GR). The combined technologies aim to improve furnace productivity with higher flame radiant heat transfer in the heating zones of a steel reheat furnace while controlling potentially higher NOx emissions from these zones. The project was conducted under a contract sponsored by the Department of Energy (DOE). Specifically, this report summarizes the results of a modeling study and an experimental study to define and evaluate the issues which affect the integration and performance of the combined technologies. Section 2.0 of the report describes the technical approach uses in the development and evaluation of the advanced steel reheat furnace. Section 3.0 presents results of the modeling study applied to a model steel furnace. Experimental validation of the modeling results obtained from EER`s Fuel Evaluation Facility (FEF) pilot-scale furnace discussed in Section 4.0. Section 5.0 provides an economic evaluation on the cost effectiveness of the advanced reheat furnace concept. Section 6.0 concludes the report with recommendations on the applicability of the combined technologies of steel reheat furnaces.

Nguyen, Q.; Koppang, R.; Maly, P.; Moyeda, D. [Energy and Environmental Research Corp., Irvine, CA (United States); Li, X. [Air Products and Chemicals, Inc., Allentown, PA (United States)

1999-01-14

3

Energy Efficiency Improvement by Measurement and Control: A Case Study of Reheating Furnaces in the Steel Industry  

E-print Network

is on energy use in steel reheating furnaces for rolling mills. The demands on the reheating process and the operational conditions that are essential for its control are described. An analysis is made of possible reductions in energy use as a result...

Martensson, A.

4

Interior of shop, showing the reheat furnaces; the vehicle in ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior of shop, showing the reheat furnaces; the vehicle in the center is a charging machine the operator of which manipulates steel ingots in the furnace, as well as in the adjacent forging hammers - Bethlehem Steel Corporation, South Bethlehem Works, Tool Steel-Electric Furnace Shop, Along Lehigh River, North of Fourth Street, West of Minsi Trail Bridge, Bethlehem, Northampton County, PA

5

DISCHARGE END OF 8" MILL REHEATING FURNACE, SHOWING MOTOROPERATED PEEL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

DISCHARGE END OF 8" MILL REHEATING FURNACE, SHOWING MOTOR-OPERATED PEEL BAR PUSHER WITH PINCH ROLLS FOR MOVING BILLETS ENDWISE OUT THE OPPOSITE SIDE OF THE FURNACE TOWARD THE CONTINUOUS ROUGHING TRAIN. - LTV Steel, 8-inch Bar Mill, Buffalo Plant, Buffalo, Erie County, NY

6

CHARGING SIDE OF #130 ELECTRIC FURNACE CO. REHEAT FURNACE IN ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

CHARGING SIDE OF #130 ELECTRIC FURNACE CO. REHEAT FURNACE IN REROLL BAY. CAKES FROM THE CASTING SHOP ARE BROUGHT UP TO ROLLING TEMPERATURE IN ONE OF TWO (#130 AND 146) GAS-FIRED FURNACES. A RADIO-CONTROLLED OVERHEAD CRANE TRANSFERS CAKES FROM FLATCARS TO THE ROLLER LINE LEADING INTO THE FURNACE. CAKES ARE HEATED AT 900-1000 DEGREES FAHRENHEIT FOR THREE TO FOUR HOURS. RATED FURNACE CAPACITY IS 100,000 LBS.\\HOUR. - American Brass Foundry, 70 Sayre Street, Buffalo, Erie County, NY

7

Development of Next Generation Heating System for Scale Free Steel Reheating  

SciTech Connect

The work carried out under this project includes development and design of components, controls, and economic modeling tools that would enable the steel industry to reduce energy intensity through reduction of scale formation during the steel reheating process. Application of scale free reheating offers savings in energy used for production of steel that is lost as scale, and increase in product yield for the global steel industry. The technology can be applied to a new furnace application as well as retrofit design for conversion of existing steel reheating furnaces. The development work has resulted in the knowledge base that will enable the steel industry and steel forging industry us to reheat steel with 75% to 95% reduction in scale formation and associated energy savings during the reheating process. Scale reduction also results in additional energy savings associated with higher yield from reheat furnaces. Energy used for steel production ranges from 9 MM Btu/ton to 16.6 MM Btu/ton or the industry average of approximately 13 MM Btu/ton. Hence, reduction in scale at reheating stage would represent a substantial energy reduction for the steel industry. Potential energy savings for the US steel industry could be in excess of 25 Trillion Btu/year when the technology is applied to all reheating processes. The development work has resulted in new design of reheating process and the required burners and control systems that would allow use of this technology for steel reheating in steel as well as steel forging industries.

Dr. Arvind C. Thekdi

2011-01-27

8

Automatic Control System of Car-Bottom Reheating Furnace  

E-print Network

flowing out and cold air coming in,but is an es sential condition to stabilize the combustion pro cedure in the furnace.And this is very important for industrial furnaces with serious leakage.Us ually,the pressure of gas forging reheating fur nace.... waste gas and heat loss THERMAL CONTROL AND CONSUMPTION OF HEAT ENF.RGY The heat losses of forging reheating furnaces 55 include mainly waste gas Q1,imperfect combustion of 50 gas Q2,radiation and stored he~t of furnace Q3,gas leakage from the gaps...

Xueqiao, M.; Weilian, X.; Hongchen, Z.

9

New burner system for reheat furnaces for maximum efficiency and low emissions  

Microsoft Academic Search

The steel industry is continuously looking for ways to improve energy efficiency and productivity. As reheat furnaces have a major impact on both, considerable work has been done in this area, and several alternative technologies have been developed. All of them, however, seem to have drawbacks as well as benefits. Low-cost solutions, such as oxygen enrichment, have technical limitations. Other

L. O. Frisk; L. J. Burfield

1993-01-01

10

New burner system for reheat furnaces for maximum efficiency and low emissions  

SciTech Connect

The steel industry is continuously looking for ways to improve energy efficiency and productivity. As reheat furnaces have a major impact on both, considerable work has been done in this area, and several alternative technologies have been developed. All of them, however, seem to have drawbacks as well as benefits. Low-cost solutions, such as oxygen enrichment, have technical limitations. Other alternatives, overcoming some of those limitations, become unreasonably complicated and expensive to install. In addition, most alternatives available to increase efficiency in reheat furnaces have environmental problems, such as increased emissions and high NO[sub x] formation. AGA Gas, Inc., in cooperation with The Timken Co., has developed a new burner system that gives maximum efficiency at a low investment cost. The first installation has been in operation in a production furnace since Jan. 1991. All important heating characteristics have been improved. At the same time, overall emissions, including NO[sub x], are substantially lower than for other burner systems. As a result, Timken has converted an additional furnace to the new technology and several more are being considered. AGA has also successfully installed the new system overseas.

Frisk, L.O. (AGA AB, Lidingo (Sweden)); Burfield, L.J. (Timken Co., Canton, OH (United States))

1993-07-01

11

New oxy-fuel burner system for reheat furnaces at Timken  

Microsoft Academic Search

A high-efficiency, low cost, oxy-fuel burner system has been developed for reheat furnaces that also results in a substantial reduction in NO[sub x] emissions compared with other systems. Through a cooperative project between Timken and AGA, it has been shown that the extremely high efficiency, along with other intangible benefits of oxy-fuel combustion can be successfully applied to reheat furnaces.

L. O. Frisk; L. J. Burfield

1994-01-01

12

An intelligent temperature control system for nature gas reheating furnace of titanium  

Microsoft Academic Search

An intelligent temperature control strategy for different heating segments is proposed based on the characteristic analysis of natural gas reheating furnace of titanium. According to errors between the furnace temperature's measured value and the goal value, a fuzzy controller is used to regulate the nature gas flux. Then the number of the flame burner is determined with expert control method.

Lv Yan; Wu Min; Lei Qi

2010-01-01

13

The development, verification, and application of a steady-state thermal model for the pusher-type reheat furnace  

NASA Astrophysics Data System (ADS)

This article outlines the development of a steady-state thermal model for the pusher-type steel reheating furnace. Problems commonly encountered with this furnace type are skidmark generation, scale formation, and high energy consumption. The objective of the work is to provide a means by which furnace users might assess the effectiveness of changes to current operating practice, proposed furnace modifications, or new furnace designs in controlling these difficulties. Since a requirement imposed on the model is to operate on current PC hardware, the assumptions and modeling procedures necessary to achieve this goal are discussed. The operation of the model, which develops the thermal history of an individual slab or billet as it passes through the furnace, is presented, and each of the three modules that comprise the model is described. Initial verification of the model has been carried out using data obtained in a separate campaign of plant trials on several 32-m furnace reheating slabs, and model predictions for steel temperatures at six locations within the steel are shown to be in good agreement with the experimental results. The model is used to examine the influence of two skid designs and several placement strategies on skidmark severity and energy losses to the skid system. Although skidmark severity at the intermediate stages of heating is shown to be dependent on both the skid type and the location of any offsets, it is demonstrated that the skidmark present in the discharged steel is determined primarily by the skid type employed over the final section of the furnace. The inclusion of a hearth in the furnace soak zone was found to impose the least severe skidmark on the product, reducing the temperature variation over the bottom face from the level of 130 °C incurred by the best of the soak zone skid configurations examined, to the level of ~85 °C. The results suggest that, in the absence of a hearth section, the use of a well-insulated, cold-rider skid system over the majority of the furnace length, followed by a single offset of all skids occurring at the transition to a short section of hot-rider skids near the furnace discharge, is sufficient to suppress the final skidmark to a level very close to the minimum achievable with that particular skid design. When assessed on the basis of minimizing both the final skidmark and the energy loss to the skid system, this configuration was found to be the best of the skid layouts examined.

Barr, P. V.

1995-08-01

14

New oxy-fuel burner system for reheat furnaces at Timken  

SciTech Connect

A high-efficiency, low cost, oxy-fuel burner system has been developed for reheat furnaces that also results in a substantial reduction in NO[sub x] emissions compared with other systems. Through a cooperative project between Timken and AGA, it has been shown that the extremely high efficiency, along with other intangible benefits of oxy-fuel combustion can be successfully applied to reheat furnaces. Previously known disadvantages associated with oxy-fuel flames in relatively low temperature processes have been overcome by the patented burner design and operational practice developed.

Frisk, L.O. (AGA AB, Lindingo (Sweden)); Burfield, L.J. (Timken Co., Canton, OH (United States))

1994-04-01

15

Billet temperature soft sensor model of reheating furnace based on RVM method  

Microsoft Academic Search

Billet temperature soft sensor model is always necessary because of lack of accurate online instrument. In this paper, a new soft sensor modeling method is proposed to predict the billet temperature of reheating furnace based on relevance vector machine (RVM). The proposed method has sparser solutions and better model generalization ability, while the uncertainty of model forecast can be given.

Yinghua Yang; Yanhui Liu; Xiaozhi Liu; Shukai Qin

2011-01-01

16

Reducing heat loss in pusher-type continuous reheating furnaces  

Microsoft Academic Search

One of the rolled-products shop at the Chelyabinsk combine has begun to use heat-insulating elements in the form of two half-rings\\u000a to line the glide tubes in its pusher-type continuous furnace. The half-rings are attached to the tubes by welding. The inner\\u000a layer of each element is made of 10-mm-thick refractory mullite-corundum panels of grade MKRKG-400, while the outer layer

A. V. Vereshchagin; R. S. Yakupov; S. V. Kul’dyakin

2007-01-01

17

Unique solution for accurate in-situ infrared profiling in reheat furnaces  

NASA Astrophysics Data System (ADS)

As thermal imaging becomes a more accepted technology in industrial environments it can provide exciting new solutions to applications that have been previously dominated by single point pyrometers. The new development of an uncooled focal plane array thermal imager with a narrow band 3.9?m filter and background compensation processing enables measurements in industrial furnaces to provide temperature profiling of the product. This paper will show why the use of a 3.9?m camera with a borescope optic is the most accurate noncontact method for in-furnace temperature measurement. This will be done using the example of a reheat furnace where in a controlled trial using an instrumented billet the measurement from the IR device was shown to accurately track the thermocouple temperature during a variety of furnace operating conditions.

Primhak, David; Wileman, Ben; Drögmöller, Peter

2010-05-01

18

30. Photocopy of photograph. STEEL PLANT, OPEN HEARTH FURNACE CHARGING ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

30. Photocopy of photograph. STEEL PLANT, OPEN HEARTH FURNACE CHARGING CREW, 1910. (From the Bethlehem Steel Corporation Colletion, Seattle, WA) - Irondale Iron & Steel Plant, Port Townsend, Jefferson County, WA

19

An investigation of reheat cracking in the weld heat affected zone of type 347 stainless steel  

NASA Astrophysics Data System (ADS)

Reheat cracking has been a persistent problem for welding of many alloys such as the stabilized stainless steels: Types 321 and 347 as well as Cr-Mo-V steels. Similar problem occurs in Ni-base superalloys termed "strain-age cracking". Cracking occurs during the post weld heat treatment. The HAZ is the most susceptible area due to metallurgical reactions in solid state during both heating and cooling thermal cycle. Many investigations have been conducted to understand the RHC mechanism. There is still no comprehensive mechanism to explain its underlying mechanism. In this study, there were two proposed cracking mechanisms. The first is the formation of a PFZ resulting in local weakening and strain localization. The second is the creep-like grain boundary sliding that causes microvoid formation at the grain boundaries and the triple point junctions. Cracking occurs due to the coalescence of the microvoids that form. In this study, stabilized grade stainless steel, Type 347, was selected for investigation of reheat cracking mechanism due to the simplicity of its microstructure and understanding of its metallurgical behavior. The Gleeble(TM) 3800 system was employed due to its capability for precise control of both thermal and mechanical simulation. Cylindrical samples were subjected to thermal cycles for the HAZ simulation followed by PWHT as the reheat cracking test. "Susceptibility C-curves" were plotted as a function of PWHT temperatures and time to failure at applied stress levels of 70% and 80% yield strength. These C-curves show the possible relationship of the reheat cracking susceptibility and carbide precipitation behavior. To identify the mechanism, the sample shape was modified containing two flat surfaces at the center section. These flat surfaces were electro-polished and subjected to the HAZ simulation followed by the placement of the micro-indentation arrays. Then, the reheat cracking test was performed. The cracking mechanism was identified by tracing the shifting of the micro-indentations compared to their original locations. At the 80% stress level, the cracking mechanism was identified as the PFZ weakening, while at the 70% stress as the creep-like grain boundary sliding. A design of experiment (DOE) using a D-optimal design was successfully employed in this study to investigate the effects of microstructures on the reheat cracking susceptibility. The microstructures were modified by heat treatment prior to the reheat cracking test. The grain size and cooling rate were found to have moderate effects on cracking susceptibility. The amount (volume fraction) of MC carbide (NbC) had a significant effect on time to failure. The more NbC formed prior to test, the longer time to failure, and the more resistance to reheat cracking. On the other hand, the amount of GB carbide (M23C6) had an insignificant effect. The statistical interaction between MC carbide with other testing parameters also had strong effect. The PWHT temperature also had significant effect as can be predicted from the susceptibility C-curves. The heat treatment schedules, during cooling and during heating schedules, were also investigated. During cooling schedule was the same schedule done earlier in this study. On the other hand, during heating schedule allowed the sample cool to room temperature prior microstructure modification followed by the reheat cracking test. During heating schedule showed an improvement in resistance to reheat cracking. Microstructure of the crack samples showed the intergranular cracking path and wedge shapes along cracking boundaries. There was also the evidence of grain boundary sliding as a result of the creep-like grain boundary sliding cracking mechanism. SEM showed the intergranular cracking and grain separation with precipitates decorated on the fracture surfaces. The precipitates were identified as Nb-rich, MC carbide (NbC). The fracture surfaces showed micro-ductility and microvoid coalescence. The size of microvoid corresponds to the size of precipitate that forms. In addition, there was

Phung-On, Isaratat

2007-12-01

20

6. DETAIL VIEW OF SPIN FORM FURNACE FOR STAINLESS STEEL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. DETAIL VIEW OF SPIN FORM FURNACE FOR STAINLESS STEEL FABRICATION. STAINLESS STEEL WAS MACHINED IN SIDE A OF THE BUILDING, BEGINNING IN 1957. (4/24/78) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

21

Development of Bimodal Grain Structures in Nb-Containing High-Strength Low-Alloy Steels during Slab Reheating  

Microsoft Academic Search

Bimodal (mixed coarse and fine) grain structures, which have been observed in some Nb-containing thermomechanically-controlled\\u000a rolled steel plates, adversely affect their mechanical properties by causing scatter in cleavage fracture stress values. It\\u000a is known that bimodal grain structures can develop during reheating prior to rolling; however, no quantitative predictions\\u000a of the level of bimodality or the critical reheat temperatures for

Debalay Chakrabarti; Claire Davis; Martin Strangwood

2008-01-01

22

RECYCLING OF ELECTRIC ARC FURNACE DUST: JORGENSEN STEEL FACILITY  

EPA Science Inventory

This document is an evaluation of the Ek Glassification Process to recycle and convert K061-tested waste (Electric Arc Furnace) and other by products of the steel-making industry into usable products. he process holds potential for replacing the need for expensive disposal costs ...

23

Development of Bimodal Grain Structures in Nb-Containing High-Strength Low-Alloy Steels during Slab Reheating  

NASA Astrophysics Data System (ADS)

Bimodal (mixed coarse and fine) grain structures, which have been observed in some Nb-containing thermomechanically-controlled rolled steel plates, adversely affect their mechanical properties by causing scatter in cleavage fracture stress values. It is known that bimodal grain structures can develop during reheating prior to rolling; however, no quantitative predictions of the level of bimodality or the critical reheat temperatures for formation have been reported. In this article, three high-strength low-alloy (HSLA) steel slabs with varying microalloying additions (Ti, Nb, and V) have been characterized in the as-continuously cast and reheated (to various temperatures in the range 1050 °C to 1225 °C) conditions to determine the link between their grain size distribution (and any bimodality observed) and the microalloy precipitate type, size, and distribution. The as-cast slabs showed inhomogeneous microalloying precipitate distributions with the separation between precipitate-rich and precipitate-poor regions being consistent with interdendritic segregation and hence, the secondary dendrite arm spacing (SDAS). The susceptibility of the slabs to the formation of bimodality, based on the steel chemical compositions and critical reheat temperature ranges has been identified, both experimentally and theoretically using ThermoCalc (Thermo-Calc Software, Stockholm, Sweden) modeling of precipitate stability in the solute-rich and the solute-depleted regions formed during casting.

Chakrabarti, Debalay; Davis, Claire; Strangwood, Martin

2008-08-01

24

Effects of flexible power cables on harmonic generation of an arc furnace steel plant  

Microsoft Academic Search

A three-phase dynamic arc furnace model is presented to investigate the effect of flexible power cables oscillations on harmonic generation of an arc-furnace steel plant. In this model, the flexible cables are presented by a varying three-phase inductor bank connected in series to the arc furnace. The self and mutual inductances of the inductors are calculated at each time step,

H. Khoshkhoo; S. H. H. Sadeghi; R. Moini; M. Jabbari

2008-01-01

25

Development and study of out-of-furnace treatment of steel using DC arc heating  

NASA Astrophysics Data System (ADS)

The results of pilot studies performed to design dc ladle-furnace units are presented. The design, equipment composition, and technical characteristics of 15-t dc ladle-furnace units, which are intended for complex treatment of steel at atmospheric pressure and in vacuum and were designed by VNIIMETMASh, TsNIIChERMET, VNIIETO, and some other enterprises, are described.

Protasov, A. V.; Bershitskii, I. M.

2012-12-01

26

The Diffusion of Innovation among Steel Firms: The Basic Oxygen Furnace  

Microsoft Academic Search

The major innovation in the steel industry in the post-World War II period has been the replacement of the open hearth furnace by the basic oxygen furnace. This article examines the diffusion of this important innovation at a more micro level than previous studies by focusing on plant behavior. Wide differences in the characteristics of the plants owned by a

Sharon Oster

1982-01-01

27

Characterization of steel mill electric-arc furnace dust.  

PubMed

In order to make a complete characterization of electric-arc furnace (EAF) dust, as hazardous industrial waste, and to solve its permanent disposal and/or recovery, bearing in mind both the volumes formed in the Croatian steel industry and experiences of developed industrial countries, a study of its properties was undertaken. For this purpose, samples of EAF dust, taken from the regular production process in the Zeljezara Sisak Steel Mill between December 2000 and December 2001, were subjected to a series of tests. The chemical composition of EAF dust samples was investigated by means of a several different analytical methods. The results from the chemical analysis show that the approximate order of abundance of major elements in EAF dusts is as follows: Fe, Zn, Mn, Ca, Mg, Si, Pb, S, Cr, Cu, Al, C, Ni, Cd, As and Hg. Granular-metric composition of single samples was determined by applying sieve separation. Scanning electron micro-structural examination of EAF dust microstructure was performed and results indicated that all twelve EAF dusts were composed of solid spherical agglomerates with Fe, Zn, Pb, O, Si and Ca as the principal element. The investigation of grain morphology and the mineralogical composition of EAF dust were taken by combination of high resolution Auger electron spectroscopy (HR AES), X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction analysis. The analysis of XPS-spectra determined the presence of zinc in the form of ZnO phase and the presence of lead in the form of PbO phase, i.e. PbSO3/PbSO4 forms. The results of the X-ray diffraction phase analysis show that the basis of the examined EAF dust samples is made of a mixture of metal oxides, silicates and sulphates. The metal concentration, anions, pH value and conductivity in water eluates was determined in order to define the influence of EAF dust on the environment. PMID:15177746

Sofili?, Tahir; Rastovcan-Mioc, Alenka; Cerjan-Stefanovi?, Stefica; Novosel-Radovi?, Vjera; Jenko, Monika

2004-06-18

28

Arc furnace recycling of chromium--nickel from stainless steel wastes  

Microsoft Academic Search

Losses of alloying metals in furnace flue dusts, grinding swarfs, and mill scale produced during the manufacture of stainless steel are substantial. About 25 million lb Cr, 8.7 million lb Ni, and 150,000 lb Mo and other critical metals can be made available annually for recycling by a process developed by the Bureau of Mines. Stainless steel wastes pelletized with

P. G. Barnard; W. M. Dressel; M. M. Fine

1977-01-01

29

Service of refractories in a double bath steel melting furnace  

Microsoft Academic Search

Conclusions The absence of regenerators, the small quantity of easily removable powdery slag in the slaggers, the low wear of the head structure, the verticals, and the lower structure of the furnace substantially simplify repair operations.

A. I. Borodulin; I. M. Konovalov; T. V. Mal'chenko; N. A. Kudryavaya; K. D. Mokrushin; A. A. Proklov; V. A. Andreev

1968-01-01

30

Improvement of the technology of the out-of-furnace treatment of wheel steel  

Microsoft Academic Search

Various versions of the deoxidation and out-of-furnace treatment of wheel steel under the OAO VMZ conditions are analyzed.\\u000a The effective partial pressure of carbon monoxide over a melt in a 130-t ladle degasser is found to be 54 ± 9 kPa. Thermodynamic\\u000a analysis of the deoxidation demonstrates that low oxygen concentrations in the melt of wheel steel can be achieved

S. S. Shibaev; A. K. Garber; K. V. Grigorovich; A. M. Arsenkin; A. A. Shishov; Yu. S. Demin; K. A. Moskovoi

2008-01-01

31

Optimization of a Steel Plant with Multiple Blast Furnaces Under Biomass Injection  

NASA Astrophysics Data System (ADS)

The allocation of resources between several blast furnaces in an integrated steelmaking plant is studied with the aim of finding the lowest specific operation cost for steel production. In order to reduce the use of fossil fuels, biomass was considered as an auxiliary reductant in the furnace after partial pyrolysis in an external unit, as a complement to heavy fuel oil. The optimization considers raw material, energy, and emission costs and a possible credit for sold power and heat. To decrease computational requirements and to guarantee that the global optimum is found, a piecewise linearized model of the blast furnace was used in combination with linear models of the sinter-, coke-, and power plants, hot stoves, and basic oxygen furnace. The optimization was carried out under different constraints on the availability of some raw materials as well as for different efficiencies of the hot stoves of the blast furnaces. The results indicate that a non-uniform distribution of the production between the furnaces can be advantageous, and some surprising findings concerning the optimal resource allocation under constrained operation are reported.

Wiklund, Carl-Mikael; Pettersson, Frank; Saxén, Henrik

2013-04-01

32

Mathematical Model for Decarburization of Ultra-low Carbon Steel in Single Snorkel Refining Furnace  

NASA Astrophysics Data System (ADS)

A dynamic model is developed to investigate decarburization behavior of a new type of refining equipment named Single Snorkel Refining Furnace (SSRF) in treating ultra-low carbon steel. Decarburization reactions in SSRF are considered to take place at three sites: Ar bubble surface, the bulk steel, and the bath surface. With the eccentricity of the porous plug ( r e/ R S) and the ratio of the snorkel diameter to the ladle diameter ( D S/ D L) of SSRF confirmed, circulation flow rate of molten steel is obtained through combined effects of vacuum pressure and gas flow rate. Besides, variation of the steel temperature is simulated associated with generated reaction heat and heat losses. The variation of C concentration with treatment time is divided into three stages in accordance with decarburization rates and the simulated C concentration is in reasonable agreement with actual production data. In the present study, both decarburization rates at three sites and their contributions to the overall decarburization at each stage are estimated for the first time. Through the present investigation, it is clear that vacuum pressure significantly influences decarburization efficiency of SSRF primarily by affecting the depth of CO nucleation in the bulk steel. Besides, effects of gas flow rate on decarburization rate of different stages are obtained and the opportunity of increasing gas flow rate during the treatment period has been clarified. The present model provides an efficient tool to comprehend the decarburization process in SSRF.

You, Zhimin; Cheng, Guoguang; Wang, Xinchao; Qin, Zhe; Tian, Jun; Zhang, Jian

2015-02-01

33

Upgrading constructed wetlands phosphorus reduction from a dairy effluent using electric arc furnace steel slag filters.  

PubMed

In 2003, a subsurface flow constructed wetlands (SSF-CW) system was built at the University of Vermont (UVM) Paul Miller Dairy Farm as an alternative nutrient management approach for treating barnyard runoff and milk parlour waste. Given the increasing problem of phosphorus (P) pollution in the Lake Champlain region, a slag based P-removal filter technology (PFT) was established (2004) at the CW with two objectives: (i) to test the filters' efficiency as an upgrade unit for improving P removal performance via SSF-CW (ii) to investigate the capacity of filters technology to remove P as a "stand alone" unit. Six individual filters (F1-F6) were filled with electric arc furnace (EAF) steel slag, each containing 112.5 kg of material with a pore volume of 21 L. F1-F4, fed with CW treated water, received approximately 2.17 g DRP kg(-1) EAF steel slag (0.25 kg DRP total) during the 259 day feeding period. F1-F4 retained 1.7 g DRP kg(-1) EAF steel slag, resulting in an average P removal efficiency of 75%. The addition of filters improved CW DRP removal efficiency by 74%. F5 and F6, fed non-treated water, received 1.9 g DRP kg(-1) EAF steel slag (0.22 kg DRP in total) and retained 1.5 g DRP kg(-1) resulting in a P removal efficiency of 72%. The establishment of the EAF slag based PFT is the first in-field evaluation of this technology to reduce P from dairy farm effluent in Vermont. PMID:17802848

Weber, D; Drizo, A; Twohig, E; Bird, S; Ross, D

2007-01-01

34

EXTERIOR VIEW, BLAST FURNACE NO. 3 (JANE FURNACE) CENTER, NO. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

EXTERIOR VIEW, BLAST FURNACE NO. 3 (JANE FURNACE) CENTER, NO. 3 CAST HOUSE TO THE LEFT, WEST ORE BRIDGE TO THE RIGHT. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 3, Donner Avenue, Monessen, Westmoreland County, PA

35

An approach for phosphate removal with quartz sand, ceramsite, blast furnace slag and steel slag as seed crystal.  

PubMed

The phosphate removal abilities and crystallization performance of quartz sand, ceramsite, blast furnace slag and steel slag were investigated. The residual phosphate concentrations in the reaction solutions were not changed by addition of the ceramsite, quartz sand and blast furnace slag. The steel slag could provide alkalinity and Ca(2+) to the reaction solution due to its hydration activity, and performed a better phosphate removal performance than the other three. Under the conditions of Ca/P 2.0, pH 8.5 and 10 mg P/L, the phosphate crystallization occurred during 12 h. The quartz sand and ceramsite did not improve the phosphate crystallization, but steel slag was an effective seed crystal. The phosphate concentration decreased drastically after 12 h after addition of steel slag, and near complete removal was achieved after 48 h. The XRD analysis showed that the main crystallization products were hydroxyapatite (HAP) and the crystallinity increased with the reaction time. Phosphate was successfully recovered from low phosphate concentration wastewater using steel slag as seed material. PMID:22378001

Qiu, Liping; Wang, Guangwei; Zhang, Shoubin; Yang, Zhongxi; Li, Yanbo

2012-01-01

36

Valorisation of electric arc furnace steel slag as raw material for low energy belite cements.  

PubMed

In this paper, the valorisation of electric arc furnace steel slag (EAFS) in the production of low energy belite cements is studied. Three types of clinkers were prepared with 0 wt.% (BC), 5 wt.% (BC5) and 10 wt.% (BC10) EAFS, respectively. The design of the raw mixes was based on the compositional indices lime saturation factor (LSF), alumina ratio (AR) and silica ratio (SR). The clinkering temperature was studied for the range 1280-1400°C; firing was performed at 1380°C based on the results regarding free lime and the evolution of microstructure. In order to activate the belite, clinkers were cooled fast by blown air and concurrent crushing. The results demonstrate that the microstructure of the produced clinkers is dominated by belite and alite crystals, with tricalcium aluminate and tetracalcium-alumino-ferrite present as micro-crystalline interstitial phases. The prepared cements presented low early strength development as expected for belite-rich compositions; however the 28-day results were 47.5 MPa, 46.6 MPa and 42.8 MPa for BC, BC5 and BC10, respectively. These values are comparable with OPC CEMI 32.5 N (32.5-52.5 MPa) according to EN 197-1. A fast setting behaviour was also observed, particularly in the case of BC10, whereas soundness did not exceed 1mm. PMID:21944704

Iacobescu, R I; Koumpouri, D; Pontikes, Y; Saban, R; Angelopoulos, G N

2011-11-30

37

Environmental impacts of asphalt mixes with electric arc furnace steel slag.  

PubMed

Electric arc furnace (EAF) steel slag can be used as an alternative high-quality material in road construction. Although asphalts with slag aggregates have been recognized as environmentally acceptable, there is a lack of data concerning the potential leaching of toxic Cr(VI) due to the highly alkaline media of EAF slag. Leaching of selected water extractable metals from slag indicated elevated concentrations of total chromium and Cr(VI). To estimate the environmental impacts of asphalt mixes with slag, leachability tests based on diffusion were performed using pure water and salt water as leaching agents. Compact and ground asphalt composites with natural aggregates, and asphalt composites in which the natural aggregates were completely replaced by slag were prepared. The concentrations of total chromium and Cr(VI) were determined in leachates over a time period of 6 mo. After 1 and 6 mo, the concentrations of some other metals were also determined in the leachates. The results indicated that chromium in leachates from asphalt composites with the addition of slag was present almost solely in its hexavalent form. However, the concentrations were very low (below 25 ?g L) and did not represent an environmental burden. The leaching of other metals from asphalt composites with the addition of slag was negligible. Therefore, the investigated EAF slag can be considered as environmentally safe substitute for natural aggregates in asphalt mixes. PMID:21712585

Mila?i?, Radmila; Zuliani, Tea; Oblak, Tina; Mladenovi?, Ana; An?ar, Janez Š?

2011-01-01

38

Advances in chemical and physical properties of electric arc furnace carbon steel slag by hot stage processing and mineral mixing.  

PubMed

Slags are recognised as a highly efficient, cost effective tool in the metal processing industry, by minimising heat losses, reducing metal oxidation through contact with air, removing metal impurities and protecting refractories and graphite electrodes. When compared to natural aggregates for use in the construction industry, slags have higher specific weight that acts as an economic deterrent. A method of altering the specific weight of EAFC slag by hot stage processing and mineral mixing, during steel production is presented in this article. The method has minimal interference with the production process of steel, even by limited additions of appropriate minerals at high temperatures. Five minerals are examined, namely perlite, ladle furnace slag, bauxite, diatomite and olivine. Measurements of specific weight are accompanied by X-ray diffraction (XRD) and fluorescence (XRF) analysis and scanning electron microscopy spectral images. It is also shown how altering the chemical composition is expected to affect the furnace refractory lining. Additionally, the process has been repeated for the most suitable mix in gas furnace and physical properties (FI, SI, LA, PSV, AAV, volume stability) examined. Alteration of the specific weight can result in tailoring slag properties for specific applications in the construction sector. PMID:25261762

Liapis, Ioannis; Papayianni, Ioanna

2015-02-11

39

Reduction of undesired harmonic components in a steel industrial plant with DC electric arc furnaces  

Microsoft Academic Search

An electric arc furnace is a nonlinear, time varying load with stochastic behavior, which gives rise to harmonics, interharminics and voltage flicker. Since a power system has finite impedance, the current distortion caused by a DC electric arc furnace load creates a corresponding voltage distortion in the supply lines. The current and voltage harmonic distortion causes several problems in electrical

Arash Dehestani Kolagar; Abbas Shoulaie

2011-01-01

40

Assessment of blast furnace retrofit for the co-manufacture of steel, electricity, and synfuels. Final report  

SciTech Connect

The objective of this study was to assess a potentially high payoff concept through preliminary engineering. Two retrofit approaches were evaluated in the study: minimal retrofit and synfuels retrofit. The minimal retrofit approach consists of operating a blast furnace with a minimum amount of changes to its operating conditions. The blast furnace combustion temperatures and amount of gas produced are maintained at substantially similar levels to normal blast furnace operation for pig iron production. In the synfuels retrofit approach, the minimum retrofit case was upgraded to an oxygen-blown, medium-Btu gasifier suitable for the production of synthesis gas. This gas can then be converted to electricity, substitute natural gas, or methanol. This concept, which was based on converting a blast furnace to a British Gas/Lurgi slagging gasifier, appears to be technically feasible. While some engineering problems were identified, they do not appear to be insurmountable. The synfuels retrofit facility, designed to produce electricity, methanol, or substitute natural gas from coal, shows a capital investment of $1.726 billion or $62.8 per trillion Btu. When compared to a grass roots facility producing the same product slate ($70.3 per trillion Btu), the retrofit represents a savings or cost avoidance of only 10% over a new facility. It can be concluded that the economics of coal gasification, in general, are currently not favorable due to the relatively low cost and apparent availability of oil and natural gas. Even site favorable situations, such as integration with steel mill operations, do not seem to be sufficient to make blast furnace retrofits economically attractive at this time. 26 refs., 15 figs., 13 tabs.

Not Available

1985-05-01

41

Comprehensive report to Congress: Clean Coal Technology Program: Blast furnace granulated coal injection system demonstration project: A project proposed by: Bethlehem Steel Corporation  

SciTech Connect

Bethlehem Steel Corporation (BSC), of Bethlehem, Pennsylvania, has requested financial assistance from DOE for the design, construction, and operation of a 2800-ton-per-day blast furnace granulated coal injection (BFGCI) system for each of two existing iron-making blast furnaces. The blast furnaces are located at BSC's facilities in Burns Harbor, Indiana. BFGCI technology involves injecting coal directly into an iron-making blast furnace and subsequently reduces the need for coke on approximately a pound of coke for pound of coal basis. BFGCI also increases blast furnace production. Coke will be replaced with direct coal injection at a rate of up to 400 pounds per NTHM. The reducing environment of the blast furnace enables all of the sulfur in the coal to be captured by the slag and hot metal. The gases exiting the blast furnace are cleaned by cyclones and then wet scrubbing to remove particulates. The cleaned blast furnace gas is then used as a fuel in plant processes. There is no measurable sulfur in the off gas. The primary environmental benefits derived from blast furnace coal injection result from the reduction of coke requirements for iron making. Reduced coke production will result in reduced releases of environmental contaminants from coking operations. 5 figs.

Not Available

1990-10-01

42

Composite Furnace Module Cooling Systems in the Electric Slag Cleaning Furnace  

Microsoft Academic Search

Electric slag cleaning furnaces have generally suff ered high rates of refractory wear in the area of the lower sidewalls that are in contact with slag. Campaign lives of around 12 months are quite common. Repairing and relining the furnace often in volves a complete cool-down, stripping out the worn refractory, installing new bricks, re-heating and bringing the furnace back

A. K. Kyllo; N. B. Gray; D. H. Montgomerie; Copper Smelter; Olympic Dam; A. Filzwieser

2005-01-01

43

Experimental evaluation of high performance base course and road base asphalt concrete with electric arc furnace steel slags.  

PubMed

The paper presents the results of a laboratory study aimed at verifying the use of two types of electric arc furnace (EAF) steel slags as substitutes for natural aggregates, in the composition of base course and road base asphalt concrete (BBAC) for flexible pavements. The trial was composed of a preliminary study of the chemical, physical, mechanical and leaching properties of the EAF steel slags, followed by the mix design and performance characterization of the bituminous mixes, through gyratory compaction tests, permanent deformation tests, stiffness modulus tests at various temperatures, fatigue tests and indirect tensile strength tests. All the mixtures with EAF slags presented better mechanical characteristics than those of the corresponding asphalts with natural aggregate and satisfied the requisites for acceptance in the Italian road sector technical standards, thus resulting as suitable for use in road construction. PMID:20566237

Pasetto, Marco; Baldo, Nicola

2010-09-15

44

Tube furnace  

DOEpatents

A vermiculite insulated tube furnace is heated by a helically-wound resistance wire positioned within a helical groove on the surface of a ceramic cylinder, that in turn is surroundingly disposed about a doubly slotted stainless steel cylindrical liner. For uniform heating, the pitch of the helix is of shorter length over the two end portions of the ceramic cylinder. The furnace is of large volume, provides uniform temperature, offers an extremely precise programmed heating capability, features very rapid cool-down, and has a modest electrical power requirement.

Foster, Kenneth G. (Livermore, CA); Frohwein, Eugene J. (San Ramon, CA); Taylor, Robert W. (Livermore, CA); Bowen, David W. (Livermore, CA)

1991-01-01

45

34. Detail of "B" furnace pour into bottle cars, furnace ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

34. Detail of "B" furnace pour into bottle cars, furnace operator on platform measures temperature inside bottle car. Looking southwest - Rouge Steel Company, 3001 Miller Road, Dearborn, Wayne County, MI

46

Banking the Furnace: Restructuring of the Steel Industry in Eight Countries.  

ERIC Educational Resources Information Center

A study examined how the cross-national differences in the social contract among managers, unions, and government influenced adjustment strategies in steel. The restructuring process in eight major steel-producing countries was studied to determine who bore the costs of restructuring--employers, employees, or government--and which industrial…

Bain, Trevor

47

Mathematical simulation of electromagnetic stirring of liquid steel in a DC arc furnace  

Microsoft Academic Search

Results are given of numerical simulation of electromagnetic stirring of metal melt in a dc arc furnace. The flow pattern\\u000a and the transport of passive admixture in baths with one and two electrodes are studied. The mathematical model describes\\u000a three-dimensional turbulent flow of electrically conducting liquid in the field of gravitational and electromagnetic forces.\\u000a The parameters of turbulence are calculated

S. A. Smirnov; V. V. Kalaev; S. M. Hekhamin; M. M. Krutyanskii; S. N. Kolgatin; I. S. Nekhamin

2010-01-01

48

Probing reheating with primordial spectrum  

E-print Network

We study the impacts of reheating temperature on the inflationary predictions of the spectral index and tensor-to-scalar ratio. Assuming that reheating process is very fast, the reheating temperature can be constrained for sinusoidal oscillation within a factor of 10 - 100 or even better with the prospect of future observations. Beyond this, we find that the predictions can also be insensitive to the reheating temperature in certain models, including the Higgs inflation.

Jinn-Ouk Gong; Shi Pi; Godfrey Leung

2015-01-29

49

Large-Scale Evaluation of Nickel Aluminide Rools In A Heat-Treat Furnace at Bethlehem Steel's (now ISG) Burns Harbor Plate Mill  

SciTech Connect

At Bethlehem Steel Burns Harbor Plate Division (now ISG Burns Harbor Plate Inc.)'s annealing furnace, new nickel aluminide intermetallic alloy rolls provide greater high-temperature strength and wear resistance compared to the conventional H series cast austenitic alloys currently used in the industry, Oak Ridge National Laboratory and Bethlehem (ISG) partnered under a U.S. Department of Energy, Office of Industrial Technology's Emerging Technology Deployment Program to demonstrate and evaluate the nickel aluminide intermetallic alloy rolls as part of an updated energy efficient large commercial annealing furnace system.

John Mengel; Anthony Martocci; Larry Fabina; RObert Petrusha; Ronald Chango

2003-09-01

50

STACK GAS REHEAT EVALUATION  

EPA Science Inventory

The report gives results of technical and economic evaluations of stack gas reheat (SGR) following wet flue gas desulfurization (FGD) for coal-fired power plants. The evaluations were based on information from literature and a survey of FGD users, vendors, and architect/engineer ...

51

The efficiency of quartz addition on electric arc furnace (EAF) carbon steel slag stability.  

PubMed

Electric arc furnace slag (EAF) has the potential to be re-utilized as an alternative to stone material, however, only if it remains chemically stable on contact with water. The presence of hydraulic phases such as larnite (2CaO SiO2) could cause dangerous elements to be released into the environment, i.e. Ba, V, Cr. Chemical treatment appears to be the only way to guarantee a completely stable structure, especially for long-term applications. This study presents the efficiency of silica addition during the deslagging period. Microstructural characterization of modified slag was performed by SEM and XRD analysis. Elution tests were performed according to the EN 12457-2 standard, with the addition of silica and without, and the obtained results were compared. These results demonstrate the efficiency of the inertization process: the added silica induces the formation of gehlenite, which, even in caustic environments, does not exhibit hydraulic behaviour. PMID:25113518

Mombelli, D; Mapelli, C; Barella, S; Gruttadauria, A; Le Saout, G; Garcia-Diaz, E

2014-08-30

52

Large-scale Evaluation of Nickel Aluminide Rolls in a Heat-Treat Furnace at Bethelehem Steel's (Now ISG) Burns Harbor Plate Mill  

SciTech Connect

At Bethlehem Steel Burns Harbor Plate Division (now ISG Burns Harbor Plate Inc.)'s annealing furnace, new nickel aluminide intermetallic alloy rolls provide greater high-temperature strength and wear resistance compared to the conventional H series cast austenitic alloys currently used in the industry. Oak Ridge National Laboratory and Bethlehem (ISG) partnered under a U.S. Department of Energy, Office of Industrial Technology's Emerging Technology Deployment Program to demonstrate and evaluate the nickel aluminide intermetallic alloy rolls as part of an updated energy efficient large commercial annealing furnace system. Many challenges were involved in this project, including developing welding procedures for joining nickel aluminide intermetallic alloys with H-series austenitic alloys, developing commercial cast roll manufacturing specifications, working with several commercial suppliers to produce a quantity of high quality, reproducible nickel aluminide rolls for a large steel industrial annealing furnace, installing and demonstrating the capability of the rolls in this furnace, performing processing trials to evaluate the benefits of new equipment and processes, and documenting the findings. Updated furnace equipment including twenty-five new automated furnace control dampers have been installed replacing older design, less effective units. These dampers, along with upgraded flame-safety control equipment and new AC motors and roll-speed control equipment, are providing improved furnace control and additional energy efficiency. Energy data shows up to a 34% energy reduction from baseline after the installation of upgraded furnace damper controls along with up to a 34% reduction in greenhouse gases, potential for an additional 3 to 6% energy reduction per campaign of light-up and shutdown, and a 46% energy reduction from baseline for limited trials of a combination of improved damper control and straight-through plate processing. The straight-through processing is now possible because of the nickel aluminide rolls which also provided plate product surface quality improvement that will allow the additional processing of surface critical material. Benefits also include associated large reductions in maintenance, reduction in spare rolls and associated component costs, and potential for greater through-put and productivity. Estimated project fuel cost reductions alone for processing 100,000 tons/yr through this furnace are almost $0.5 million/yr with the new dampers, and more than $600,000/yr with straight-through processing and new damper control, assuming natural gas prices of $6.00/MMBtu. The nickel aluminide rolls are competitively priced with conventional H series alloy rolls.

Mengel, J.

2003-12-16

53

Energy audit of three energy-conserving devices in a steel-industry demonstration program. Task I. Hague forge furnaces. Final report  

SciTech Connect

A program to demonstrate to industry the benefits of installing particular types of energy-conserving devices and equipment was carried out. One of these types of equipment and the results obtained under production conditions in commercial plants are described. The equipment under consideration includes improved forge furnaces and associated heat-recovery components. They are used to heat steel to about 2300 F prior to hot forging. The energy-conserving devices include improved insulation, automatic air-fuel ratio control, and a ceramic recuperator that recovers heat from hot combustion gases and delivers preheated air to high-temperature recirculating burners. Twelve Hague furnaces and retrofit packages were purchased and installed by eleven host forge shops that agree to furnish performance data for the purpose of demonstrating the energy and economic savings that can be achieved in comparison with existing equipment. Fuel savings were reported by comparing the specific energy consumption (Btu's per pound of steel heated) for each Hague furnace with that of a comparison furnace. Economic comparisons were made using payback period based on annual after-tax cash flow. Payback periods for the Hague equipment varied from less than two years to five years or more. In several cases, payback times were high only because the units were operated at a small fraction of their available capacity.

Lownie, H.W.; Holden, F.C.

1982-06-01

54

Thermal reactive deposition coating of chromium carbide on die steel in a fluidized bed furnace  

Microsoft Academic Search

The application of thermal reactive deposition (TRD) and diffusion technique to form a carbide layer for enhancing the tool life is of increasing importance in surface modification of steel. This study focused on investigating the influences of the amount of addition on the formation rate of the chromium carbide layers by three different alloy powders, namely, pure chromium, 71Cr-29Fe-0.03C, and

Fan-Shiong Chen; Pee-Yew Lee; Ming-Chyi Yeh

1998-01-01

55

Model of phosphorus precipitation and crystal formation in electric arc furnace steel slag filters.  

PubMed

The objective of this study was to develop a phosphorus retention mechanisms model based on precipitation and crystallization in electric arc furnace slag filters. Three slag columns were fed during 30 to 630 days with a reconstituted mining effluent at different void hydraulic retention times. Precipitates formed in columns were characterized by X-ray diffraction and transmission electronic microscopy. The proposed model is expressed in the following steps: (1) the rate limiting dissolution of slag is represented by the dissolution of CaO, (2) a high pH in the slag filter results in phosphorus precipitation and crystal growth, (3) crystal retention takes place by filtration, settling and growth densification, (4) the decrease in available reaction volume is caused by crystal and other particulate matter accumulation (and decrease in available reaction time), and (5) the pH decreases in the filter over time if the reaction time is too low (which results in a reduced removal efficiency). Crystal organization in a slag filter determines its phosphorus retention capacity. Supersaturation and water velocity affect crystal organization. A compact crystal organization enhances the phosphorus retention capacity of the filter. A new approach to define filter performance is proposed: saturation retention capacity is expressed in units of mg P/mL voids. PMID:22208381

Claveau-Mallet, Dominique; Wallace, Scott; Comeau, Yves

2012-02-01

56

Analysis of arc emission spectra of stainless steel electric arc furnace slag affected by fluctuating arc voltage.  

PubMed

Control of chromium oxidation in the electric arc furnace (EAF) is a significant problem in stainless steel production due to variations of the chemical compositions in the EAF charge. One potential method to control chromium oxidation is to analyze the emission spectrum of the electric arc in order to find indicators of rising chromium content in slag. The purpose of this study was to determine if slag composition can be gained by utilizing electric arc emission spectra in the laboratory environment, despite electric arc voltage fluctuations and varying slag composition. The purpose of inducing voltage fluctuation was to simulate changes in the industrial EAF process. The slag samples were obtained from Outokumpu Stainless Oy Tornio Works, and three different arc currents were used. The correlation analysis showed that the emission spectra offer numerous peak ratios with high correlations to the X-ray fluorescence-measured slag CrO(x)/FeO(x) and MnO/SiO2 ratios. These ratios are useful in determining if the reduction agents have been depleted in the EAF. The results suggest that analysis of laboratory-scale electric arc emission spectra is suitable for indicating the high CrO(x) or MnO content of the slag despite the arc fluctuations. Reliable analysis of other slag components was not successful. PMID:24405950

Aula, Matti; Mäkinen, Ari; Fabritius, Timo

2014-01-01

57

The Effect of Chemical Composition on Microstructure and Properties of Intercritically Reheated Coarse-Grained Heat-Affected Zone in X70 Steels  

NASA Astrophysics Data System (ADS)

The current study investigates the effect of different levels of Ti, N, and Ti/N ratios on microstructure and properties in the intercritically reheated coarse-grained heat-affected zone (ICCGHAZ) of two-pass submerged arc welds in API 5L grade X70 pipe. Gleeble simulation was employed to reproduce the ICCGHAZ of actual welds. Hardness and Charpy V-notch (CVN) tests were performed on the simulated samples. The microstructure of simulated ICCGHAZ was characterized by optical microscopy and scanning electron microscopy (SEM). LePera color etching technique was employed to identify and quantify the martensitic-austenitic (M-A) constituent. Results show that the simulated ICCGHAZ exhibited extremely low toughness, but in the studied range of Ti and N, there was no correlation with Ti/N ratio. The beneficial effect of near-stoichiometric Ti/N ratio observed in coarse-grained heat-affected zone (CGHAZ) did not translate to ICCGHAZ. This was because of the negative effect of the blocky M-A constituent formed on prior austenite grain boundaries.

Zhu, Zhixiong; Kuzmikova, Lenka; Li, Huijun; Barbaro, Frank

2013-12-01

58

Microstructural characterization of modified 25Cr-35Ni centrifugally cast steel furnace tubes  

SciTech Connect

HP steels modified with Nb and Nb-plus-Ti, produced in the form of centrifugally cast tubes, were characterized by means of light optical microscopy, scanning electron microscopy (SEM) with secondary and backscattered electron imaging, and transmission electron microscopy (TEM) with energy-dispersive spectroscopy (EDS) and selected area diffraction. A complete description of the phases present in the as-cast, welded, and aged condition was made as a function of the modifying elements. The chromium carbide stoichiometry, secondary precipitation, NbC instability at elevated temperatures, the G-phase transformation, and the effect of Ti on this reaction are discussed. It is indicated that partial transformation of G-phase in the alloy modified with Ti is one of the explanations for the superior creep properties observed in this material.

Almeida, Luiz Henrique de; Ribeiro, Andre Freitas; Le May, Iain

2002-10-15

59

INTERIOR VIEW LOOKING WEST, CAST HOUSE OF BLAST FURNACE NO. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR VIEW LOOKING WEST, CAST HOUSE OF BLAST FURNACE NO. 1 AND BLAST FURNACE NO. 2. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 1 & No. 2, Donner Avenue, Monessen, Westmoreland County, PA

60

50. Taken from highline; "B" furnace slag pots, pipe is ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

50. Taken from high-line; "B" furnace slag pots, pipe is main blast furnace gas line from "C" furnace dust catcher; levy, slag hauler, removing slag. Looking east - Rouge Steel Company, 3001 Miller Road, Dearborn, Wayne County, MI

61

Reheating constraints in inflationary magnetogenesis  

SciTech Connect

Among primordial magnetogenesis models, inflation is a prime candidate to explain the current existence of cosmological magnetic fields. Assuming conformal invariance to be restored after inflation, their energy density decreases as radiation during the decelerating eras of the universe, and in particular during reheating. Without making any assumptions on inflation, on the magnetogenesis mechanism and on how the reheating proceeded, we show that requiring large scale magnetic fields to remain subdominant after inflation gives non-trivial constraints on both the reheating equation of state parameter and the reheating energy scale. In terms of the so-called reheating parameter, we find that ln R{sub rad} > ?10.1 for large scale magnetic fields of the order 5 × 10{sup ?15} Gauss today. This bound is then compared to those already derived from Cosmic Microwave Background (CMB) data by assuming a specific inflationary model. Avoiding magnetic field backreaction is always complementary to CMB and can give more stringent limits on reheating for all high energy models of inflation. For instance, a large field matter dominated reheating cannot take place at an energy scale lower than typically 500 GeV if the magnetic field strength today is B{sub 0} = 5 × 10{sup ?15} G, this scale going up to 10{sup 10} GeV if B{sub 0} = 10{sup ?9} G.

Demozzi, Vittoria; Ringeval, Christophe, E-mail: vittoria.demozzi@uclouvain.be, E-mail: christophe.ringeval@uclouvain.be [Centre for Cosmology, Particle Physics and Phenomenology, Institute of Mathematics and Physics, Louvain University, 2 Chemin du Cyclotron, 1348 Louvain-la-Neuve (Belgium)

2012-05-01

62

Diagnostics and Control of Natural Gas-Fired furnaces via Flame Image Analysis using Machine Vision & Artificial Intelligence Techniques  

SciTech Connect

A new approach for the detection of real-time properties of flames is used in this project to develop improved diagnostics and controls for natural gas fired furnaces. The system utilizes video images along with advanced image analysis and artificial intelligence techniques to provide virtual sensors in a stand-alone expert shell environment. One of the sensors is a flame sensor encompassing a flame detector and a flame analyzer to provide combustion status. The flame detector can identify any burner that has not fired in a multi-burner furnace. Another sensor is a 3-D temperature profiler. One important aspect of combustion control is product quality. The 3-D temperature profiler of this on-line system is intended to provide a tool for a better temperature control in a furnace to improve product quality. In summary, this on-line diagnostic and control system offers great potential for improving furnace thermal efficiency, lowering NOx and carbon monoxide emissions, and improving product quality. The system is applicable in natural gas-fired furnaces in the glass industry and reheating furnaces used in steel and forging industries.

Shahla Keyvan

2005-12-01

63

Enhanced reheating via Bose condensates  

SciTech Connect

In supersymmetric extensions of the particle physics standard model, gauge invariant combinations of squarks and sleptons (flat directions) can acquire large expectation values during a period of cosmological inflation. If the inflaton sector couples to matter fields via these flat directions, then new channels for efficient reheating, in particular, via parametric resonance instabilities, are opened up. These can lead to efficient reheating induced by the flat directions even if the bare coupling constants are small. In this Letter we discuss various channels which yield this 'enhanced reheating' effect, and we address some cosmological consequences.

Allahverdi, Rouzbeh [Theory Group, TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, V6T 2A3 (Canada); Brandenberger, Robert [Physics Department, Brown University, Providence, Rhode Island 02912 (United States); Perimeter Institute, Waterloo, Ontario, N2J 2W9 (Canada); Physics Department, McGill University, 3600 University Road, Montreal, Quebec, H3A 2T8 (Canada); Mazumdar, Anupam [Physics Department, McGill University, 3600 University Road, Montreal, Quebec, H3A 2T8 (Canada)

2004-10-15

64

Effect of Controlled Hot Rolling Parameters on Microstructure of a Nb-Microalloyed Steel Sheet  

SciTech Connect

The design of controlled rolling process of microalloyed steel sheets is affected by several factors. In this investigation, effect of the reheating, finishing and coiling temperatures of rolling, which are considered as the most effective parameters on microstructure of hot rolled products has been studied. For this purpose, seven different reheating temperatures between 1000 to 1300 deg. C with 50 deg. C increments, three different finishing temperatures of 950, 900 and 850 deg. C below the non-recrystallization temperature and one temperature of 800 deg. C in the inter critical range and four different coiling temperatures of 550, 600, 650 and 700 deg. C were chosen. By soaking the specimens in furnace, the grain coarsening temperature (T{sub gc}) is obtained about 1250 deg. C. Hence, for these kinds of steels, the reheating temperature 1200 to 1250 deg. C is recommended. Moreover, it is observed that decreasing the coiling and finishing temperatures causes more grain refinement of microstructure and the morphology is changed from polygonal ferrite to acicular one. Findings of this research provide a good connection among reheating, finishing and coiling temperatures and microstructural features of Nb-microalloyed steel sheets.

Khaki, Daavood Mirahmadi [Department of Materials Science and Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Abedi, Amir [Department of Metallurgical Engineering, Shahid Rajaee Teacher Training University, Tehran (Iran, Islamic Republic of)

2011-01-17

65

Universe reheating after inflation  

SciTech Connect

We study the problem of scalar particle production after inflation by an inflaton field which is oscillating rapidly relative to the expansion of the universe. We use the framework of the chaotic inflation scenario with quartic and quadratic inflaton potentials. Particles produced are described by a quantum scalar field {chi}, which is coupled to the inflaton via linear and quadratic couplings. The particle production effect is studied using the standard technique of Bogolyubov transformations. Particular attention is paid to parametric resonance phenomena which take place in the presence of the quickly oscillating inflaton field. We have found that in the region of applicability of perturbation theory the effects of parametric resonance are crucial, and estimates based on first-order Born approximation often underestimate the particle production. In the case of the quartic inflaton potential {ital V}({ital cphi})={lambda}{ital cphi}{sup 4}, the particle production process is very efficient for either type of coupling between the inflaton field and the scalar field {chi} even for small values of coupling constants. The energy density of the universe after the decay of the inflaton oscillations is in this case a factor [{lambda} ln(1/{lambda})]{sup {minus}1} times larger than the corresponding estimates based on first-order Born approximation. In the case of the quadratic inflaton potential the reheating process depends crucially on the type of coupling between the inflaton and the scalar field {chi} and on the magnitudes of the coupling constants. If the inflaton coupling to fermions and its linear (in inflaton field) coupling to scalar fields are suppressed, then, as previously discussed by Kofman, Linde, and Starobinsky, the inflaton field will eventually decouple from the rest of the matter, and the residual inflaton oscillations may provide the (cold) dark matter of the universe.

Shtanov, Y. [Bogolyubov Institute for Theoretical Physics, Kiev 252143 (Ukraine)] [Bogolyubov Institute for Theoretical Physics, Kiev 252143 (Ukraine); [Department of Physics, Brown University, Providence, Rhode Island 02912 (United States); Traschen, J. [Department of Physics and Astronomy, University of Massachusetts, Amherst, Massachusetts 01003 (United States)] [Department of Physics and Astronomy, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Brandenberger, R. [Department of Physics, Brown University, Providence, Rhode Island 02912 (United States)] [Department of Physics, Brown University, Providence, Rhode Island 02912 (United States)

1995-05-15

66

Solar furnaces  

Microsoft Academic Search

A solar furnace is a device for applying high temperatures to a specimen by concentrating solar radiation on it. A brief historical review concerning the development of solar furnaces is presented and fundamental operational and design principles for solar furnaces are discussed. A paraboloidal mirror is used as a radiation concentrator of the reflection type. According to the procedures used

T. Sakurai

1977-01-01

67

Solar furnace  

Microsoft Academic Search

A solar furnace receiving reflected solar energy from a battery of remote, positionable mirrors with the furnace having primary and secondary reflectors directing concentrated radiant energy toward a Fresnel lens is described. The focal point of the lens is located within a furnace chamber into which is advanced a carbon conduit, the advancing end of which is vaporized by focal

1977-01-01

68

Solar furnace  

Microsoft Academic Search

The solar furnace is constructed of evacuated glass block solar elements that include an interior face, or surface, of zinc. Because of this material, substantial solar radiant energy is retained and radiated to the interior of the furnace, permitting the furnace to reach temperatures of 300° C. and more when located at latitudes between the 35th parallels. Evacuated insulating elements

Clavier

1985-01-01

69

Reheating Phase Diagram for Higgs Inflation  

E-print Network

We investigate the impact on the inflationary predictions from various reheating histories which are characterized by an e-folding number $N_{\\mathrm{reh}}$ and an effective equation-of-state parameter $w_{\\mathrm{reh}}$ during reheating process. For Higgs inflation with a non-minimal coupling to gravity, the predictions are obtained on the $N_{\\mathrm{reh}}\\!\\!-\\!w_{\\mathrm{reh}}$ reheating phase diagram. We find that the predictions are insensitive to reheating phase. Within the $1\\sigma$ region of the scalar spectral index $n_s$ reported by Planck 2014 Preliminary, almost all possible reheating histories are allowed on the reheating phase diagram, where Higgs inflation with canonical reheating history $w_{\\mathrm{reh}}=0$ lies near the upper edge of the $1\\sigma$ range of $n_s$. Future measurements of $n_s$ with high precision will identify the reheating physics of Higgs inflation.

Cai, Rong-Gen; Wang, Shao-Jiang

2015-01-01

70

Release of H and He from tic, stainless steel, and graphite by pulsed electron and furnace heating*1  

NASA Astrophysics Data System (ADS)

Substantial release of implanted D and 3He from TiC coatings and SS 304, and of D from graphite, by 50ns pulsed electron beam (e-beam) heating has been observed and is compared to release by isochronal furnace heating. A substantial enhancement in the fractional D release was found for D saturated TiC (0.25 D to host atom ratio) compared with low fluence implants for both e-beam and furnace heating. This enhancement was not observed for graphite and SS 304. E-beam release of 3He from TiC was observed to be unaffected by the presence of saturation concentrations of D. Comparison to the calculated time evolution of the temperature profiles suggests a simple model for the D release based on diffusion-limited release in the case of pulsed e-beam treatments and trap-limited release in the case of furnace bulk heating. These processes are closely related to hydrogen recycle in tokamaks and have implications for T inventory control and He ash removal.

Picraux, S. T.; Wampler, W. R.

1980-10-01

71

Energy Savings in Electric Arc Furnace Melting  

E-print Network

Arc furnace melting which at one time was almost exclusively used to produce alloy steel and steel castings is now widely accepted in the industry as an efficient process to produce all types of steel and iron. Presently, about 28% of steel...

Lubbeck, W.

1982-01-01

72

21. Photocopy of ca. 1951 view (when furnaces were still ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

21. Photocopy of ca. 1951 view (when furnaces were still in blast) looking north at central furnace complex with railroad cars of furnace charging materials in foreground and No. 2 Furnace at left. Photo marked on back 'David W. Corson from A. Devaney, N.Y.' - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

73

42. Casting floor, "B" furnace, pour in progress; mudgun is ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

42. Casting floor, "B" furnace, pour in progress; mudgun is to right of furnace; operator takes temperature of iron in trough during pout. Looking south - Rouge Steel Company, 3001 Miller Road, Dearborn, Wayne County, MI

74

3. LOOKING WEST INSIDE ELECTRIC FURNACE BUILDING ON CHARGING FLOOR. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. LOOKING WEST INSIDE ELECTRIC FURNACE BUILDING ON CHARGING FLOOR. VIEW OF 7 1/2 TON CAPACITY ALLIANCE SIDE DOOR CHARGING MACHINE. - U.S. Steel Duquesne Works, Electric Furnace Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

75

4. LOOKING SOUTHEAST INSIDE OF ELECTRIC FURNACE BUILDING ON GROUND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. LOOKING SOUTHEAST INSIDE OF ELECTRIC FURNACE BUILDING ON GROUND FLOOR OF CHARGING AISLE. VIEW OF 50 TON CAPACITY CHARGING BUCKET. - U.S. Steel Duquesne Works, Electric Furnace Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

76

INTERIOR VIEW LOOKING EAST, BLAST FURNACE NO. 1 CLOSEUP, IRON ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR VIEW LOOKING EAST, BLAST FURNACE NO. 1 CLOSE-UP, IRON NOTCH IN CENTER. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 1 & No. 2, Donner Avenue, Monessen, Westmoreland County, PA

77

INTERIOR VIEW OF BLAST FURNACE NO. 3 LOOKING EAST, SLAG ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR VIEW OF BLAST FURNACE NO. 3 LOOKING EAST, SLAG RUNNERS & GATES IN FOREGROUND. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 3, Donner Avenue, Monessen, Westmoreland County, PA

78

VIEW LOOKING NORTHWEST WITH OPENHEARTH TO LEFT WITH BLAST FURNACE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW LOOKING NORTHWEST WITH OPEN-HEARTH TO LEFT WITH BLAST FURNACE NO. 2 AND CAST HOUSE TO THE RIGHT. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 1 & No. 2, Donner Avenue, Monessen, Westmoreland County, PA

79

DETAIL VIEW OF BLAST FURNACE NO. 3 AREA BELOW BUSTLE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

DETAIL VIEW OF BLAST FURNACE NO. 3 AREA BELOW BUSTLE PIPE, CINDER NOTCH IN CENTER, SLAG RUNNER IN FOREGROUND. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 3, Donner Avenue, Monessen, Westmoreland County, PA

80

GENERAL VIEW OF TURBOBLOWER BUILDING (LEFT), BLAST FURNACE (CENTER), AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

GENERAL VIEW OF TURBO-BLOWER BUILDING (LEFT), BLAST FURNACE (CENTER), AND HOT BLAST STOVES (RIGHT). - Republic Iron & Steel Company, Youngstown Works, Haselton Blast Furnaces, West of Center Street Viaduct, along Mahoning River, Youngstown, Mahoning County, OH

81

55. GENERAL NORTHEASTERN VIEW OF DOROTHY SIX BLAST FURNACE COMPLEX ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

55. GENERAL NORTHEASTERN VIEW OF DOROTHY SIX BLAST FURNACE COMPLEX WITH LADLE HOUSE AND IRON DESULPHERIZATION BUILDING ON RIGHT. (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

82

22. DETAIL OBLIQUE VIEW NORTHWEST OF FURNACE 2, SHOWING GENERAL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. DETAIL OBLIQUE VIEW NORTHWEST OF FURNACE 2, SHOWING GENERAL CONSTRUCTION. CONCRETE PAD AT LEFT IS SITE OF FORMER FURNACE USED TO HEAT URANIUM BILLETS. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

83

Rotary furnace supervisory control system at Timken`s Gambrinus furnace No. 3  

Microsoft Academic Search

During 1994, the Timken Co. upgraded the rotary hearth billet furnace at the Gambrinus plant. As part of the upgrade, a new furnace supervisory control system was installed. This system includes an on-line thermal model which calculates steel temperatures and gradients while accounting for changing project dimensions and steel grades. Temperature and production rate set points are calculated to consistently

L. E. Cates; E. Schweinsberg; T. Fearn

1995-01-01

84

Inflation, Reheating and Dark Matter  

E-print Network

In a recent paper, Liddle and Urena-Lopez suggested that to have a unified model of inflation and dark matter is imperative to have a proper reheating process where part of the inflaton field remains. In this paper I propose a model where this is possible. I found that, incorporating the effect of plasma masses generated by the inflaton products, enable us to stop the process. A numerical estimated model is presented.

Victor H. Cardenas

2007-01-22

85

Studies on the corrosion resistance of reinforced steel in concrete with ground granulated blast-furnace slag--An overview.  

PubMed

The partial replacement of clinker, the main constituent of ordinary Portland cement by pozzolanic or latent hydraulic industrial by-products such as ground granulated blast furnace slag (GGBFS), effectively lowers the cost of cement by saving energy in the production process. It also reduces CO2 emissions from the cement plant and offers a low priced solution to the environmental problem of depositing industrial wastes. The utilization of GGBFS as partial replacement of Portland cement takes advantage of economic, technical and environmental benefits of this material. Recently offshore, coastal and marine concrete structures were constructed using GGBFS concrete because high volume of GGBFS can contribute to the reduction of chloride ingress. In this paper, the influence of using GGBFS in reinforced concrete structures from the durability aspects such as chloride ingress and corrosion resistance, long term durability, microstructure and porosity of GGBFS concrete has been reviewed and discussed. PMID:16930831

Song, Ha-Won; Saraswathy, Velu

2006-11-16

86

Blast furnace stove control  

SciTech Connect

This paper outlines the process model and model-based control techniques implemented on the hot blast stoves for the No. 7 Blast Furnace at the Inland Steel facility in East Chicago, Indiana. A detailed heat transfer model of the stoves is developed. It is then used as part of a predictive control scheme to determine the minimum amount of fuel necessary to achieve the blast air requirements. The controller also considers maximum and minimum temperature constraints within the stove.

Muske, K.R. [Villanova Univ., PA (United States). Dept. of Chemical Engineering; Hansen, G.A.; Howse, J.W.; Cagliostro, D.J. [Los Alamos National Lab., NM (United States); Chaubal, P.C. [Inland Steel Industries Inc., East Chicago, IN (United States). Research Labs.

1998-12-31

87

Direct measurement of solids: High temperature sensing: Phase 2, Experimental development and testing on furnace-heated steel blocks  

SciTech Connect

Using average velocity measurements to estimate average profile temperature shows promise and merits further investigation. The current generation of electromagnetic acoustic transducers (EMATs) can transmit and detect signals in steel below the magnetic transition temperature. Techniques for calibrating ultrasonic velocity to internal temperature need further development. EMATs are inadequate ultrasonic transmitters for these applications. A high-energy, pulsed laser capable of generating more intense ultrasonic signals should be investigated as a transmitter. Recommendations are given for further work.

Lemon, D.K.; Daly, D.S.

1985-12-01

88

Reheating predictions in single field inflation  

E-print Network

Reheating is a transition era after the end of inflation, during which the inflaton is converted into the particles that populate the Universe at later times. No direct cosmological observables are normally traceable to this period of reheating. Indirect bounds can however be derived. One possibility is to consider cosmological evolution for observable CMB scales from the time of Hubble crossing to the present time. Depending upon the model, the duration and final temperature after reheating, as well as its equation of state, are directly linked to inflationary observables. For single-field inflationary models and for reheating scenarios that may be approximated by a constant equation of state, it is straightforward to derive relations between the reheating duration (or final temperature), its equation of state parameter, and the scalar power spectrum amplitude and spectral index. As a result, one may employ current bounds on inflation to constrain the nature of reheating. Alternatively, it is possible to fur...

Cook, Jessica L; Easson, Damien A; Krauss, Lawrence M

2015-01-01

89

Nitrogen control in electric arc furnace steelmaking  

Microsoft Academic Search

Electric arc furnace produced steels are usually characterized by relatively high nitrogen content. This restricts their use in applications requiring controlled nitrogen content, such as deep drawing quality products. This report presents the results of an EPRI Center for Materials Production and steel industry study of methods for controlling or reducing the nitrogen content of EAF steels. The study involved

J. Thomas; C. Scheid; G. Geiger; C. Czarnik; D. Teall

1992-01-01

90

Reheating for closed string inflation  

SciTech Connect

We point out some of the outstanding challenges for embedding inflationary cosmology within string theory studying the process of reheating for models where the inflaton is a closed string mode parameterising the size of an internal cycle of the compactification manifold. A realistic model of inflation must explain the tiny perturbations in the cosmic microwave background radiation and also how to excite the ordinary matter degrees of freedom after inflation, required for the success of Big Bang Nucleosynthesis. We study these issues focusing on two promising inflationary models embedded in LARGE volume type IIB flux compactifications. We show that phenomenological requirements and consistency of the effective field theory treatment imply the presence at low energies of a hidden sector together with a visible sector, where the Minimal Supersymmetric Standard Model fields are residing. A detailed calculation of the inflaton coupling to the fields of the hidden sector, visible sector, and moduli sector, reveals that the inflaton fails to excite primarily the visible sector fields, instead hidden sector fields are excited copiously after the end of inflation. This sets severe constraints on hidden sector model building where the most promising scenario emerges as a pure N = 1 SYM theory, forbidding the kinematical decay of the inflaton to the hidden sector. In this case it is possible to reheat the Universe with the visible degrees of freedom even though in some cases we discover a new tension between TeV scale SUSY and reheating on top of the well-known tension between TeV scale SUSY and inflation.

Cicoli, Michele [Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22603 Hamburg (Germany); Mazumdar, Anupam, E-mail: michele.cicoli@desy.de, E-mail: a.mazumdar@lancaster.ac.uk [Physics Department, Lancaster University, Lancaster, LA1 4YB (United Kingdom)

2010-09-01

91

Curvaton reheating in tachyonic braneworld inflation  

SciTech Connect

The curvaton reheating in a tachyonic braneworld inflationary universe model with an exponential potential is studied. We have found that the energy density in the kinetic epoch, has a complicated dependencies of the scale factor. For different scenarios the temperature of reheating is computed, finding an upper limit that lies in the range 10{sup 14}-10{sup 16} GeV.

Campuzano, Cuauhtemoc; Campo, Sergio del; Herrera, Ramon [Instituto de Fisica, Pontificia Universidad Catolica de Valparaiso, Casilla 4059, Valparaiso (Chile); Departamento de Ciencias Fisicas, Universidad Andres Bello, Avenida Republica 237, Santiago (Chile)

2005-10-15

92

Reheating Metastable O'Raifeartaigh Models  

SciTech Connect

In theories with multiple vacua, reheating to a temperature greater than the height of a barrier can stimulate transitions from a desirable metastable vacuum to a lower energy state. We discuss the constraints this places on various theories and demonstrate that in a class of supersymmetric models this transition does not occur even for arbitrarily high reheating temperature.

Craig, Nathaniel J.; /SLAC /Stanford U., ITP; Fox, Patrick J.; /LBL, Berkeley; Wacker, Jay G.; /SLAC /Stanford U., ITP

2006-12-13

93

Reheating Metastable O'Raifeartaigh Models  

SciTech Connect

In theories with multiple vacua, reheating to a temperature greater than the height of a barrier can stimulate transitions from a desirable metastable vacuum to a lower energy state. We discuss the constraints this places on various theories and demonstrate that in a class of supersymmetric models this transition does not occur even for arbitrarily high reheating temperature.

Craig, Nathaniel J.; Fox, Patrick J.; Wacker, Jay G.

2006-12-05

94

Reheating metastable O'Raifeartaigh models  

SciTech Connect

In theories with multiple vacua, reheating to a temperature greater than the height of a barrier can stimulate transitions from a desirable metastable vacuum to a lower energy state. We discuss the constraints this places on various theories and demonstrate that in a class of supersymmetric models this transition does not occur even for arbitrarily high reheating temperature.

Fox, Patrick; Craig, Nathaniel J.; Fox, Patrick J.; Wacker, Jay G.

2006-11-01

95

Bottom electrodes of DC electric arc furnaces  

Microsoft Academic Search

The design of dc electric arc furnaces (DCEAFs) is similar to that of three-phase arc steel-melting furnaces (ASFs) and differs from it only in the presence of one or more graphite roof electrodes (cathodes) and one or more bottom electrodes (anodes), which convey current to a metal to be melted. As compared to ASFs, DCEAFs have the following main advantages:

M. Ya. Kaplun

2009-01-01

96

Reheating in a Brane Monodromy Inflation Model  

E-print Network

We study reheating in a recently proposed brane "monodromy inflation" model in which the inflaton is the position of a D4 brane on a "twisted torus". Specifically, we study the repeated collisions between the D4 brane and a D6 brane (on which the Standard Model fields are assumed to be localized) at a fixed position along the monodromy direction as the D4 brane rolls down its potential. We find that there is no trapping of the rolling D4 brane until it reaches the bottom of its potential, and that reheating is entirely described by the last brane encounter. Previous collisions have negligible effect on the brane velocity and hence on the reheat temperature. In the context of our setup, reheating is efficient and the reheat temperature is therefore high.

Brandenberger, Robert H; Lorenz, Larissa C

2008-01-01

97

Load characteristics and harmonic analysis of DC arc furnace  

Microsoft Academic Search

In this paper, the authors discuss the load characteristics of a steel factory containing a DC arc furnace. In order to reduce the cost, the arc furnace works during the off-peak period. While the furnace is in operation, the variation of active power and reactive power is quite large. In order to understand the load characteristics, the statistics method is

Chi-Jui Wu; Tsu-Hsun Fu; You-Jen Chen

2000-01-01

98

VIEW LOOKING NORTH, VIEW OF BLAST FURNACE NO. 2 (LEFT) ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW LOOKING NORTH, VIEW OF BLAST FURNACE NO. 2 (LEFT) SHARING THE SAME CAST HOUSE WITH BLAST FURNACE NO. 1. ORE BRIDGE & BLOWER HOUSE TO RIGHT, HULETT CAR DUMPER IS IN LEFT FOREGROUND. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 1 & No. 2, Donner Avenue, Monessen, Westmoreland County, PA

99

EXTERIOR VIEW, NO. 3 CAST HOUSE CENTER AND BLAST FURNACE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

EXTERIOR VIEW, NO. 3 CAST HOUSE CENTER AND BLAST FURNACE NO. 3 (JANE FURNACE)/ORE BRIDGE TO THE RIGHT, WITH SINTERING PLANT CONVEYORS & TRANSFER HOUSE IN FOREGROUND. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 3, Donner Avenue, Monessen, Westmoreland County, PA

100

Development of Ni{sub 3}Al alloys for use as transfer rolls in hot processing of steels. CRADA final report  

SciTech Connect

The purpose of this cooperative effort was to evaluate the potential of Ni{sub 3}Al alloys, such as IC221M and IC396M, for use as transfer rolls in heating treating furnaces and slab reheating furnaces used during the normal hot processing of steel ingots into rolled products. Rolls consist of three parts: the center tube section which forms the roll surface in direct contact with the steel, and the sections welded at each end of the tube, called trunnions, which bear the load. The work in this CRADA focused on weldments and base materials. The transfer rolls in the furnaces used in the hot processing of steel have been made, almost exclusively, from iron-chromium-nickel heat resistant alloys for over 35 years. The iron-based heat resistant alloys experience a variety of problems when exposed to temperatures above 760 C including: cracking, dimensional instability, and excessive oxidation. Many defects in rolled steel products can be traced directly to rolls used in the processing. Also the demand for higher quality products, spurred in part by competition from foreign producers, requires that various avenues for improving overall quality of rolled steel products be pursued. Initial work done by the Contractor and Metallamics indicated that Ni{sub 3}Al alloys may perform better than existing iron-chromium-nickel alloys do as transfer rolls in heat treating furnaces. The use of Ni{sub 3}Al may lead to rolls with longer operational life, improved high temperature oxidation resistance and mechanical properties, higher quality rolled steel products, and improved energy and operational efficiencies in the hot processing of steel. The goal of the work was to test Ni{sub 3}Al alloys for the transfer roll application in order to improve process efficiency, minimize waste by virtue of producing rolled steel of higher quality and to enhance the competitiveness of US-based steel producers.

Santella, M.L. [Oak Ridge National Lab., TN (United States); McDonald, R. [Metallamics, Transverse City, MI (United States)

1996-05-01

101

Continuous austempering fluidized bed furnace. Final report  

SciTech Connect

The intended objective of this project was to show the benefits of using a fluidized bed furnace for austenitizing and austempering of steel castings in a continuous manner. The division of responsibilities was as follows: (1) design of the fluidized bed furnace--Kemp Development Corporation; (2) fabrication of the fluidized bed furnace--Quality Electric Steel, Inc.; (3) procedure for austempering of steel castings, analysis of the results after austempering--Texas A and M University (Texas Engineering Experiment Station). The Department of Energy provided funding to Texas A and M University and Kemp Development Corporation. The responsibility of Quality Electric Steel was to fabricate the fluidized bed, make test castings and perform austempering of the steel castings in the fluidized bed, at their own expense. The project goals had to be reviewed several times due to financial constraints and technical difficulties encountered during the course of the project. The modifications made and the associated events are listed in chronological order.

Srinivasan, M.N. [Lamar Univ., Beaumont, TX (United States). Dept. of Mechanical Engineering] [Lamar Univ., Beaumont, TX (United States). Dept. of Mechanical Engineering

1997-09-23

102

MicroNiobium Alloy Approach in Medium and High Carbon Steel Bar, Plate and Sheet Products  

NASA Astrophysics Data System (ADS)

The recently developed application of the MicroNiobium Alloy Approach® in medium- and high-carbon steel long products, sheets, and plate steels enhances both the metallurgical properties and processability, as well as reducing the operational cost per tonne of production. The process and product metallurgy improvements relate to the Nb-pinning effect of the austenite grain boundaries. The metallurgical mechanism of the MicroNiobium Alloy Approach is related to the retardation of austenite grain coarsening during reheat furnace soaking of the billets, slabs, or shapes before rolling. Variable grain size is induced by temperature fluctuations and inhomogeneity during the heating of the slabs in the reheat furnace. Such fluctuations can occur because of variations in the air- to gas-ratio, directly affecting the adiabatic flame temperature and heat input into the slabs. This approach contributes to the achievement of an ultrafine grain, homogeneous higher carbon microstructures that exhibit superior toughness, high strength, less mechanical property variation in the final hot-rolled product, and reduced cost of quality. The reduced cost of quality far exceeds the additional alloy cost for the Nb addition.

Jansto, Steven G.

2014-04-01

103

Late reheating, hadronic jets, and baryogenesis.  

PubMed

If inflaton couples very weakly to ordinary matter, the reheating temperature of the Universe can be lower than the electroweak scale. In this Letter we show that the late reheating occurs in a highly nonuniform way, within narrow areas along the jets produced by ordinary particles originated from inflaton decays. Depending on inflaton mass and decay constant, the initial temperature inside the lumps of the overheated plasma may be large enough to trigger the unsuppressed sphaleron processes with baryon number nonconservation. This allows for efficient local electroweak baryogenesis at reheating temperatures TR approximately O(10) GeV. PMID:15089191

Asaka, Takehiko; Grigoriev, Dmitri; Kuzmin, Vadim; Shaposhnikov, Mikhail

2004-03-12

104

Furnace assembly  

DOEpatents

A method of and apparatus for heating test specimens to desired elevated temperatures for irradiation by a high energy neutron source. A furnace assembly is provided for heating two separate groups of specimens to substantially different, elevated, isothermal temperatures in a high vacuum environment while positioning the two specimen groups symmetrically at equivalent neutron irradiating positions.

Panayotou, Nicholas F. (Kennewick, WA); Green, Donald R. (Richland, WA); Price, Larry S. (Pittsburg, CA)

1985-01-01

105

General view of blast furnace "A"; looking southeast; The building ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

General view of blast furnace "A"; looking southeast; The building to the right is the crucible steel building - Bethlehem Steel Corporation, South Bethlehem Works, Blast Furnace "A", Along Lehigh River, North of Fourth Street, West of Minsi Trail Bridge, Bethlehem, Northampton County, PA

106

19. MOLTEN IRON FLOWS INTO A 'BOTTLE' AT FURNACE NO. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

19. MOLTEN IRON FLOWS INTO A 'BOTTLE' AT FURNACE NO. 1. THE IRON WILL BE TRANSPORTED BY RAIL TO THE OPEN HEARTH OR BASIC OXYGEN FURNACES, WHERE IT IS A MAJOR COMPONENT IN THE PRODUCTION OF STEEL. - Corrigan, McKinney Steel Company, 3100 East Forty-fifth Street, Cleveland, Cuyahoga County, OH

107

Monitoring power system response to UHP arc furnace operations  

SciTech Connect

This article reports on the use of a PC based data acquisition and analysis system for monitoring response of a power system to the operation of two electric arc furnaces. The topics of the article include a description of the steel complex, the data acquisition system, monitoring one furnace ramping up, monitoring loss of one furnace, monitoring loss of two furnaces, and the results of monitoring and analysis.

Sharma, C.; Julien, K.S. (Univ. of the West Indies, St. Augustine (Trinidad and Tobago). Dept. of Electrical and Computer Engineering)

1994-01-01

108

49. Taken from highline; "McKinley hat" remains on "B" furnace; ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

49. Taken from high-line; "McKinley hat" remains on "B" furnace; no longer used, "McKinley hat was open receptacle with bell below. Hat carried charge to furnace top, dumping it to bell; bell locked onto furnace top, dropping charge into furnace. Looking east - Rouge Steel Company, 3001 Miller Road, Dearborn, Wayne County, MI

109

Solar furnace  

Microsoft Academic Search

A solar furnace electricity generating system is provided herein. It includes a concentrator and accumulator for the sun's rays to generate a concentrated high temperature solar beam. A heat hearth is disposed, e.g., in the ground, to absorb the concentrated high temperature solar beam. A plurality of concentric alternating heat-transfer-medium-containing chambers and heat absorption zones are provided around the heat

1983-01-01

110

EXTERIOR VIEW LOOKING WEST,BLAST FURNACE TO THE RIGHT, ORE YARD ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

EXTERIOR VIEW LOOKING WEST,BLAST FURNACE TO THE RIGHT, ORE YARD TO THE CENTER, HEYL & PATTERSON CAR DUMPER TO THE LEFT. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 3, Donner Avenue, Monessen, Westmoreland County, PA

111

Crystal Furnace  

NASA Technical Reports Server (NTRS)

A "melt recharging" technique which eliminates the cooldown and heating periods in a crystal "growing" crucible, resulted from a Jet Propulsion Laboratory (JPL)/Kayex Corporation program. Previously, the cost of growing the silicon solar cells had been very high. The JPL/Kayex system improved productivity by serially growing crystals from the same crucible using a melt recharger which made it possible to add raw silicon to an operating crucible. An isolation value, developed by Kayex, allowed the hopper to be lowered into the crucible without disturbing the inert gas atmosphere. The resulting product, a CG6000 crystal growing furnace, has become the company's major product.

1985-01-01

112

Quantifying the reheating temperature of the universe  

NASA Astrophysics Data System (ADS)

The aim of this paper is to determine an exact definition of the reheat temperature for a generic perturbative decay of the inflaton. In order to estimate the reheat temperature, there are two important conditions one needs to satisfy: (a) the decay products of the inflaton must dominate the energy density of the universe, i.e. the universe becomes completely radiation dominated, and (b) the decay products of the inflaton have attained local thermodynamical equilibrium. For some choices of parameters, the latter is a more stringent condition, such that the decay products may thermalise much after the beginning of radiation-domination. Consequently, we have obtained that the reheat temperature can be much lower than the standard-lore estimation. In this paper we describe under what conditions our universe could have efficient or inefficient thermalisation, and quantify the reheat temperature for both the scenarios. This result has an immediate impact on many applications which rely on the thermal history of the universe, in particular gravitino abundance. Instant thermalisation: when the inflaton decay products instantly thermalise upon decay. Efficient thermalisation: when the inflaton decay products thermalise right at the instant when radiation epoch starts dominating the universe. Delayed thermalisation: when the inflaton decay products thermalise deep inside the radiation dominated epoch after the transition from inflaton-to-radiation domination had occurred. This paper is organised as follows. In Section 2 we set the stage and write down the relevant equations for our analysis. The standard lore about the reheating epoch is briefly commented in Section 3. Section 4 is devoted to present our analysis, in which we study the conditions under which the plasma attains thermalisation. Later on, in Section 5 we discuss the concept of reheat temperature such as to properly capture the issues of thermalisation. Finally, we conclude in Section 6.

Mazumdar, Anupam; Zaldívar, Bryan

2014-09-01

113

Reheating in Inflationary Cosmology: Theory and Applications  

E-print Network

Reheating is an important part of inflationary cosmology. It describes the production of Standard Matter particles after the phase of accelerated expansion. We give a review of the reheating process, focusing on an in-depth discussion of the preheating stage which is characterized by exponential particle production due to a parametric resonance or tachyonic instability. We give a brief overview of the thermalization process after preheating and end with a survey of some applications to supersymmetric theories and to other issues in cosmology such as baryogenesis, dark matter and metric preheating.

Allahverdi, Rouzbeh; Cyr-Racine, Francis-Yan; Mazumdar, Anupam

2010-01-01

114

Reheating in Inflationary Cosmology: Theory and Applications  

NASA Astrophysics Data System (ADS)

Reheating is an important part of inflationary cosmology. It describes the production of Standard Model particles after the phase of accelerated expansion. We review the reheating process with a focus on an in-depth discussion of the preheating stage, which is characterized by exponential particle production due to a parametric resonance or tachyonic instability. We give a brief overview of the thermalization process after preheating and end with a survey of some applications to supersymmetric theories and to other issues in cosmology, such as baryogenesis, dark matter, and metric preheating.

Allahverdi, Rouzbeh; Brandenberger, Robert; Cyr-Racine, Francis-Yan; Mazumdar, Anupam

2010-11-01

115

Heat Pipe Precools and Reheats Dehumidified Air  

NASA Technical Reports Server (NTRS)

Precooling and reheating by heat pipe reduces operating costs of air-conditioning. Warm air returned from air-conditioned space and cooled air supplied are precooled and reheated, respectively, by each other through a heat pipe. Heat-pipe technology brought to bear on problem of conserving airconditioning energy in hot, humid environments. Any increase in the cost of equipment due to installation of heat-pipe heat exchangers expected to be recovered in energy savings during service period of 2 years or less.

Koning, R. C.; Boggs, W. H.; Barnett, U. R.; Dinh, K.

1986-01-01

116

TRP0033 - PCI Coal Combustion Behavior and Residual Coal Char Carryover in the Blast Furnace of 3 American Steel Companies during Pulverized Coal Injection (PCI) at High Rates  

SciTech Connect

Combustion behavior of pulverized coals (PC), gasification and thermal annealing of cokes were investigated under controlled environments. Physical and chemical properties of PCI, coke and carbon residues of blast furnace dust/sludge samples were characterized. The strong influence of carbon structure and minerals on PCI reactivity was demonstrated. A technique to characterize char carryover in off gas emissions was established.

Veena Sahajwalla; Sushil Gupta

2005-04-15

117

Rotary furnace supervisory control system at Timken`s Gambrinus furnace No. 3  

SciTech Connect

During 1994, the Timken Co. upgraded the rotary hearth billet furnace at the Gambrinus plant. As part of the upgrade, a new furnace supervisory control system was installed. This system includes an on-line thermal model which calculates steel temperatures and gradients while accounting for changing project dimensions and steel grades. Temperature and production rate set points are calculated to consistently produce properly heated pieces. The set point control strategy will reduce fuel consumption, decrease temperature variations between pieces, prevent overheating, and minimize the amount of scaling and decarburization of the steel.

Cates, L.E.; Schweinsberg, E. [Davy International, Pittsburgh, PA (United States). Automation Services Div.; Fearn, T. [Timken Co., Canton, OH (United States)

1995-07-01

118

Curvaton reheating in a logamediate inflationary model  

SciTech Connect

In a logamediate inflationary universe model we introduce the curvaton field in order to bring this inflationary model to an end. In this approach we determine the reheating temperature. We also outline some interesting constraints on the parameters that describe our models. Thus, we give the parameter space in this scenario.

Campo, Sergio del; Herrera, Ramon; Saavedra, Joel; Campuzano, Cuauhtemoc; Rojas, Efrain [Instituto de Fisica, Pontificia Universidad Catolica de Valparaiso, Avenida Brasil 2950, Valparaiso (Chile); Departamento de Fisica, Facultad de Fisica e Inteligencia Artificial, Universidad Veracruzana, 91000, Xalapa Veracruz (Mexico)

2009-12-15

119

Inflation from strings 2; Reheating and baryogenesis  

SciTech Connect

The authors study the reheating process which takes place after the two periods of inflation that arise from a string-inspired cosmological model. In this paper baryogenesis mechanisms and a possible solution for the magnetic monopole problem that are compatible with string-motivated inflationary scenarios are discussed.

Bento, M.C.; Bertolami, O.; Sa, P.M. (Centro de Fisica da Materia Condensada, Av. Prof. Gama Pinto, 2, 1699 Lisboa Codex (PT))

1992-04-10

120

No-reheat air-conditioning  

NASA Technical Reports Server (NTRS)

Air conditioning system, for environmentally controlled areas containing sensitive equipment, regulates temperature and humidity without wasteful and costly reheating. System blends outside air with return air as dictated by various sensors to ensure required humidity in cooled spaces (such as computer room).

Obler, H. D.

1980-01-01

121

Magneto-reheating constraints from curvature perturbations  

SciTech Connect

As additional perturbative degrees of freedom, it is known that magnetic fields of inflationary origin can source curvature perturbations on super-Hubble scales. By requiring the magnetic generated curvature to remain smaller than its inflationary adiabatic counterpart during inflation and reheating, we derive new constraints on the maximal field value today, the reheating energy scale and its equation of state parameter. These bounds end up being stronger by a few order of magnitude than those associated with a possible backreaction of the magnetic field onto the background. Our results are readily applicable to any slow-roll single field inflationary models and any magnetic field having its energy density scaling as a{sup ?} during inflation. As an illustrative example, massive inflation is found to remain compatible with a magnetic field today B{sub 0} = 5 × 10{sup ?15} G for some values of ? only if a matter dominated reheating takes place at energies larger than 10{sup 5} GeV. Conversely, assuming ? = ?1, massive inflation followed by a matter dominated reheating cannot explain large scale magnetic fields larger than 10{sup ?20} G today.

Ringeval, Christophe [Centre for Cosmology, Particle Physics and Phenomenology, Institute of Mathematics and Physics, Louvain University, 2 Chemin du Cyclotron, 1348 Louvain-la-Neuve (Belgium); Suyama, Teruaki; Yokoyama, Jun'ichi, E-mail: christophe.ringeval@uclouvain.be, E-mail: suyama@resceu.s.u-tokyo.ac.jp, E-mail: yokoyama@resceu.s.u-tokyo.ac.jp [Research Center for the Early Universe (RESCEU), Graduate School of Science, The University of Tokyo, Tokyo 113-0033 (Japan)

2013-09-01

122

Enhanced humification by carbonated basic oxygen furnace steel slag--II. Process characterization and the role of inorganic components in the formation of humic-like substances.  

PubMed

Enhanced humification by abiotic catalysts is a potentially promising supplementary composting method for stabilizing organic carbon from biowastes. In this study, the role of steel slag in the transformation of humic precursors was directly characterized by measuring the variance in dissolved organic carbon (DOC), spectroscopic parameters (E(600)), and the concentration and molecular weight change of humic-like substances (HLS) during the process. In addition, a mechanistic study of the process was explored. The results directly showed that steel slag greatly accelerated the formation of HLS. The findings indicate that Fe(III)-and Mn(IV)-oxides in steel slag act as oxidants and substantially enhance the polycondensation of humic precursors. Moreover, the reaction appears to suppress the release of metals from steel slag to a certain extent under acidic conditions. This can be attributed to the cover of HLS on the external surface of steel slag, which is significant for its environmentally sound reuse. PMID:22497707

Qi, Guangxia; Yue, Dongbei; Fukushima, Masami; Fukuchi, Shigeki; Nishimoto, Ryo; Nie, Yongfeng

2012-06-01

123

Nitrogen control in electric arc furnace steelmaking  

SciTech Connect

Electric arc furnace produced steels are usually characterized by relatively high nitrogen content. This restricts their use in applications requiring controlled nitrogen content, such as deep drawing quality products. This report presents the results of an EPRI Center for Materials Production and steel industry study of methods for controlling or reducing the nitrogen content of EAF steels. The study involved a series of trials performed by North Star Steel at its Michigan Division plant. A major conclusion of the study is that nitrogen content can be reduced through an increase in carbon monoxide evolution sustained by oxygen injection and carbon additions.

Thomas, J.; Scheid, C.; Geiger, G.; Czarnik, C.; Teall, D. (North Star Steel Co., Monroe, MI (United States))

1992-12-01

124

5. SOUTHERN VIEW OF BLAST FURNACES No. 3, No. 4, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. SOUTHERN VIEW OF BLAST FURNACES No. 3, No. 4, AND No. 6, WITH ORE YARD IN THE FOREGROUND. BUILDING ON THE LEFT IS THE CENTRAL BOILER HOUSE. (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

125

39. Detail view of No. 2 Furnace iron runner; rod ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

39. Detail view of No. 2 Furnace iron runner; rod or poker at right was used to unplug iron notch. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

126

38. Base of No. 2 Furnace showing iron runner to ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

38. Base of No. 2 Furnace showing iron runner to ladle car on floor of casting shed. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

127

8. QUENCHING MECHANISM FOR THE CONTINUOUS ELECTRIC FURNACE HEAT TREATING ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. QUENCHING MECHANISM FOR THE CONTINUOUS ELECTRIC FURNACE HEAT TREATING LINE AT THE HEAT TREATMENT PLANT OF THE DUQUESNE WORKS. - U.S. Steel Duquesne Works, Heat Treatment Plant, Along Monongahela River, Duquesne, Allegheny County, PA

128

VIEW OF DOUBLE ROOF CAST HOUSE OF BLAST FURNACE NO. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF DOUBLE ROOF CAST HOUSE OF BLAST FURNACE NO. 3. COKE PLANT & MONESSEN BUSINESS DISTRICT IN BACKGROUND. VIEW FACING EAST. - Pittsburgh Steel Company, Monessen Works, Donner Avenue, Monessen, Westmoreland County, PA

129

CLOSEUP VIEW OF OPEN HEARTH COMPLEX (INCLUDING PIT FURNACE BUILDING, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

CLOSE-UP VIEW OF OPEN HEARTH COMPLEX (INCLUDING PIT FURNACE BUILDING, BLOOMING & BAR MILL, & HOT BEDS) & RAIL MILL. - Pittsburgh Steel Company, Monessen Works, Donner Avenue, Monessen, Westmoreland County, PA

130

VIEW FACING EAST, VIEW FROM RIVER OF BLAST FURNACE NO. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW FACING EAST, VIEW FROM RIVER OF BLAST FURNACE NO. 3. DORR THICKENER & ORE BRIDGE AT LEFT, HOT BLAST STOVES & DUST CATCHER CENTER, CAST HOUSE AT RIGHT. - Pittsburgh Steel Company, Monessen Works, Donner Avenue, Monessen, Westmoreland County, PA

131

DETAIL VIEW OF THE #2 BLAST FURNACE AND SKIP HOIST. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

DETAIL VIEW OF THE #2 BLAST FURNACE AND SKIP HOIST. DUST CATCHER IS AT THE RIGHT. VIEW IS FROM THE EAST. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

132

Parametric Amplification of Gravitational Fluctuations during Reheating  

SciTech Connect

Cosmological perturbations can undergo amplification by parametric resonance during preheating even on scales larger than the Hubble radius, without violating causality. A unified description of gravitational and matter fluctuations is crucial to determine the strength of the instability. To extract specific signatures of the oscillating inflaton field during reheating, it is essential to focus on a variable describing metric fluctuations which is constant in the standard analyses of inflation. For a massive inflaton without self-coupling, we find no additional growth of superhorizon modes during reheating beyond the usual predictions. For a massless self-coupled inflaton, there is a sub-Hubble scale resonance. {copyright} {ital 1999} {ital The American Physical Society}

Finelli, F.; Brandenberger, R. [Department of Physics, Brown University, Providence, Rhode Island 02912 (United States)] [Department of Physics, Brown University, Providence, Rhode Island 02912 (United States); Finelli, F. [Department of Physics and INFN, Bologna (Italy)] [Department of Physics and INFN, Bologna (Italy)

1999-02-01

133

Electric arc furnace modelling from a “power quality” point of view  

Microsoft Academic Search

Arc furnaces are mainly used in steel production for the recycling of scrap. Due to the dynamic behaviour of the arc during the melting process, an arc furnace is a major source of perturbations on a high voltage network. Whether AC or DC is used to supply the furnace, the perturbations are of random nature and encompass a frequency range

I. Vervenne; K. Van Reusel; R. Belmans

2007-01-01

134

Modelling of a DC arc furnace for optimal integration with the supply system  

Microsoft Academic Search

DC are furnaces have gained increasing favour with steel makers all over the world. DC arc furnaces have advantages over their conventional AC counterparts because of their greater supply-friendly nature. Although DC are furnaces still generate flicker, the stochastic component in their harmonics arc reduced and their demands on the supply network are much more compatible with the supply than

J. Bekker; P. H. Swart; C. F. Landy; D. A. Marshall

1995-01-01

135

Gas Turbine Reheat Using In-Situ Combustion  

SciTech Connect

Siemens Westinghouse Power Corporation (SWPC) is developing in-situ reheat (fuel injection via airfoil injection) as a means for increasing cycle efficiency and power output, with possibly reduced emissions. This report discusses engineering cycle evaluations on various reheat approaches, using GateCycle and ChemCad software simulations of typical F-class and G-class engines, modified for alternative reheat cycles. The conclusion that vane 1 reheat offers the most advantageous design agrees with the conclusions of the detailed chemical kinetics (Task 2) as verified by high temperature testing (Task 3) and Blade path CFD (Task 1) tasks. The second choice design option (vane 2 reheat after vane 1 reheat) is also validated in all tasks. A conceptual design and next recommended development tasks are presented.

R.A. Newby; D.M. Bachovchin; T.E. Lippert

2004-04-29

136

Heat treatment furnace  

DOEpatents

A furnace heats through both infrared radiation and convective air utilizing an infrared/purge gas design that enables improved temperature control to enable more uniform treatment of workpieces. The furnace utilizes lamps, the electrical end connections of which are located in an enclosure outside the furnace chamber, with the lamps extending into the furnace chamber through openings in the wall of the chamber. The enclosure is purged with gas, which gas flows from the enclosure into the furnace chamber via the openings in the wall of the chamber so that the gas flows above and around the lamps and is heated to form a convective mechanism in heating parts.

Seals, Roland D; Parrott, Jeffrey G; DeMint, Paul D; Finney, Kevin R; Blue, Charles T

2014-10-21

137

Energy use in the U.S. steel industry: a historical perspective and future opportunities  

SciTech Connect

The U.S. steel industry has taken enormous strides over the past decades to reduce its energy consumption; since the end of World War II, the industry has reduced its energy intensity (energy use per shipped ton) by 60 percent. Between 1990 and 1998 alone, intensity has dropped from 20 to 18 million Btu (MBtu) per ton. This figure is projected to decrease to 15 MBtu/ton by 2010 with an asymptotic trend towards 14 MBtu/ton. Domestic shipments are projected to flatten out over the next decade to around 105 million tons which means that total energy consumption will also decrease. Historically, the steel industry has accounted for about 6 percent of U.S. energy consumption. Today, that figure is less than 2 percent and will decrease further to 1.5 percent by 2010. The primary causes for the decrease in energy consumption since WWII are: The use of pellets in the blast furnace and the application of new technology in the ironmaking process to further reduce fuel rates per net ton of hot metal (NTHM); The total replacement of the open hearth process by basic oxygen and electric furnaces; The almost total replacement of ingot casting by continuous casting (which improved yield dramatically and thus reduced the tons of raw steel required per ton of shipments); and The growth of the electric furnace sector of the industry at the expense of hot metal-based processes (which has also stimulated scrap recycling so that about 55 percent of ''new'' steel is now melted from scrap steel). This report focuses on the concept of good practices (i.e., those that are sustainable and can use today's technology). If all the industry could operate on this basis, the additional savings per ton could total 2 MBtu, As further restructuring occurs and the swing from hot metal-based to electric furnace-based production continues, the average consumption will approach the good practice energy per ton. Further savings will accrue through new technology, particularly in the areas of reduced blast furnace fuel rates and reheating efficiency, both of which relate to large tonnages of material.

Stubbles, John

2000-09-01

138

Reheating, multifield inflation and the fate of the primordial observables  

SciTech Connect

We study the effects of perturbative reheating on the evolution of the curvature perturbation ?, in two-field inflation models. We use numerical methods to explore the sensitivity of f{sub NL}, n{sub ?} and r to the reheating process, and present simple qualitative arguments to explain our results. In general, if a large non-Gaussian signal exists at the start of reheating, it will remain non-zero at the end of reheating. Unless all isocurvature modes have completely decayed before the start of reheating, we find that the non-linearity parameter, f{sub NL}, can be sensitive to the reheating timescale, and that this dependence is most appreciable for 'runaway' inflationary potentials that only have a minimum in one direction. For potentials with a minimum in both directions, f{sub NL} can also be sensitive to reheating if a mild hierarchy exists between the decay rates of each field. Within the class of models studied, we find that the spectral index n{sub ?}, is fairly insensitive to large changes in the field decay rates, indicating that n{sub ?} is a more robust inflationary observable, unlike the non-linearity parameter f{sub NL}. Our results imply that the statistics of ?, especially f{sub NL}, can only be reliably used to discriminate between models of two-field inflation if the physics of reheating are properly accounted for.

Leung, Godfrey; Tarrant, Ewan R.M.; Copeland, Edmund J. [School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG7 2RD (United Kingdom); Byrnes, Christian T., E-mail: ppxgl@nottingham.ac.uk, E-mail: ppxet@nottingham.ac.uk, E-mail: cbyrnes@cern.ch, E-mail: ed.copeland@nottingham.ac.uk [PH-TH Division, CERN, CH-1211, Genève 23 (Switzerland)

2012-09-01

139

Model Fe-Al Steel with Exceptional Resistance to High Temperature Coarsening. Part II: Experimental Validation and Applications  

NASA Astrophysics Data System (ADS)

In order to achieve a fine uniform grain-size distribution using the process of thin slab casting and directing rolling (TSCDR), it is necessary to control the grain-size prior to the onset of thermomechanical processing. In the companion paper, Model Fe- Al Steel with Exceptional Resistance to High Temperature Coarsening. Part I: Coarsening Mechanism and Particle Pinning Effects, a new steel composition which uses a small volume fraction of austenite particles to pin the growth of delta-ferrite grains at high temperature was proposed and grain growth was studied in reheated samples. This paper will focus on the development of a simple laboratory-scale setup to simulate thin-slab casting of the newly developed steel and demonstrate the potential for grain size control under industrial conditions. Steel bars with different diameters are briefly dipped into the molten steel to create a shell of solidified material. These are then cooled down to room temperature at different cooling rates. During cooling, the austenite particles nucleate along the delta-ferrite grain boundaries and greatly retard grain growth. With decreasing temperature, more austenite particles precipitate, and grain growth can be completely arrested in the holding furnace. Additional applications of the model alloy are discussed including grain-size control in the heat affected zone in welds and grain-growth resistance at high temperature.

Zhou, Tihe; Zhang, Peng; O'Malley, Ronald J.; Zurob, Hatem S.; Subramanian, Mani

2015-01-01

140

Electromelt furnace evaluation  

SciTech Connect

An electromelt furnace was designed, built, and operated at the Idaho National Engineering Laboratory to demonstrate the suitability of this equipment for large-scale processing of radioactive wastes in iron-enriched basalt. Several typical waste compositions were melted and cast. The furnace was disassembled and the components evaluated. Calcines and fluorides attacked the furnace lining, unoxidized metals accumulated under the slag, and electrode attrition was high.

Reimann, G.A.; Welch, J.M.

1981-09-01

141

Microstructural studies of advanced austenitic steels  

Microsoft Academic Search

This report presents the first complete microstructural and analytical electron microscopy study of Alloy AX5, one of a series of advanced austenitic steels developed by Maziasz and co-workers at Oak Ridge National Laboratory, for their potential application as reheater and superheater materials in power plants that will reach the end of their design lives in the 1990's. The advanced steels

J. A. Todd; Jyh-Ching Ren

1989-01-01

142

Inflation and reheating in spontaneously generated gravity  

NASA Astrophysics Data System (ADS)

Inflation is studied in the context of induced gravity (IG) ??2R, where R is the Ricci scalar, ? a scalar field and ? a dimensionless constant, and diverse symmetry-breaking potentials V(?) are considered. In particular we compared the predictions for Landau-Ginzburg and Coleman-Weinberg type potentials and their possible generalizations with the most recent data. We find that large field inflation generally leads to fewer constraints on the parameters and the shape of the potential whereas small field inflation is more problematic and, if viable, implies more constraints, in particular, on the parameter ?. We also examined the reheating phase and obtained an accurate analytical solution for the dynamics of the inflaton and the Hubble parameter by using a multiple scale analysis. The solutions were then used to study the average expansion of the Universe, the average equation of state for the scalar field and both the perturbative and resonant decays of the inflaton field.

Cerioni, A.; Finelli, F.; Tronconi, A.; Venturi, G.

2010-06-01

143

Simulating (p)reheating after inflation via the DCE?  

E-print Network

We note some close parallels between preheating/perturbative reheating, (p)reheating, models in post-inflationary cosmology and the dynamical Casimir effect (DCE) in quantum optics. For the plasma-mirror model we show how the effective plasma mass (arising from conduction electrons) behaves like an oscillating inflaton field, while created photons behave like a scalar field coupled quadratically to the inflaton. Furthermore, the effect of spacetime expansion can also be incorporated by varying the dielectric function. We propose an experiment that could mimic (p)reheating for both narrow and broad parametric resonance, by employing technology already being used in attempts to detect DCE photons via plasma-mirrors.

Wade Naylor

2014-09-18

144

Simulating (p)reheating after inflation via the DCE?  

E-print Network

We note some close parallels between preheating/perturbative reheating, (p)reheating, models in post-inflationary cosmology and the dynamical Casimir effect (DCE) in quantum optics. For the plasma-mirror model we show how the effective plasma mass (arising from conduction electrons) behaves like an oscillating inflaton field, while created photons behave like a scalar field coupled quadratically to the inflaton. Furthermore, the effect of spacetime expansion can also be incorporated by varying the dielectric function. We propose an experiment that could mimic (p)reheating for both narrow and broad parametric resonance, by employing technology already being used in attempts to detect DCE photons via plasma-mirrors.

Naylor, Wade

2014-01-01

145

High temp vacuum furnace offers new option  

SciTech Connect

Vacuum furnaces operating up to 2,350 F are commonly used for metallurgical processes such as hardening tool steels, treating super alloys, power metal sintering, and brazing. Traditionally electric, these furnaces are costly to operate and maintain. They are often sensitivity to impurities driven off work pieces in the heating chamber because the vapors condense on the walls of the heating chamber and negatively effect operation. The gas-fired vacuum furnace now in development by Surface Combustion, with support from the Gas Research Institute (GRI) will, however, have none of the drawbacks of the electric models while maintaining or improving on performance. Costly electric operating and demand charges will be avoided through the use of natural gas as a fuel. Its ``hot wall`` furnace design means that impurities driven off the work piece can be pulled out of the chamber before they condense. Because ceramic radiant tubes will be used in conjunction with the hot wall design, temperature uniformity and productivity are expected to equal, or surpass, that of the electric furnaces.

NONE

1995-12-11

146

Carbon Arc Image Furnaces  

Microsoft Academic Search

Various optical systems are discussed with reference to their use with carbon arc image furnaces. A new optical system which employs two elliptical mirrors is described and shown to have numerous practical advantages. Using modifications of motion picture projection lamps, measurements have been made of carbon arc image furnaces ranging up to more than 26-kw power input, producing approximately 3000-watts

M. R. Null; W. W. Lozier

1958-01-01

147

Pulverized coal injection operation on CSC No. 3 blast furnace  

SciTech Connect

The pulverized coal injection system was introduced for the first time in No. 1 and No. 2 blast furnace at China Steel Corporation (CSC) in 1988. Currently the coal injection rate for both blast furnaces has steadily risen to 70--89 kg/thm (designed value). No 3 blast furnace (with an inner volume of 3400 m3) was also equipped with a PCI system of Armco type and started coal injection on November 17, 1993. During the early period, some problems such as injection lance blocking, lance-tip melting down, flexible hose wear, grind mill tripping occasionally interrupted the stable operation of blast furnace. After a series of efforts offered on equipment improvement and operation adjustment, the PC rate currently reaches to 90--110 kg/thm and furnace stable operation is still being maintained with productivity more than 2.20.

Chan, C.M.; Hsu, C.H. [China Steel Corp., Kaohsiung (Taiwan, Province of China)

1996-12-31

148

Process to eliminate hazardous components from the electric arc furnace flue dust and recovering of metals  

SciTech Connect

This patent describes a method to recover metals from flue dust generated in an electric arc furnace, the method comprising: charging pelletized or powder flue dust into an electric induction furnace between induction susceptors; sealing of the furnace top to prevent entry of air; injecting natural gas through the bottom of the electric induction furnace as a solitary reducing agent; heating the charge by electromagnetic induction of the susceptors to provide reduction energy; recovering of heavy metals as a zinclead-cadmium alloy in a condenser at the top of the furnace; burning and scrubbing exiting gases in the condenser; and melting the remaining iron to produce steel and slag.

Lazcano-Navarro, A.

1988-08-09

149

INTERIOR VIEW SHOWING FURNACE KEEPER OBSERVING FURNACE THROUGH BLUE GLASS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR VIEW SHOWING FURNACE KEEPER OBSERVING FURNACE THROUGH BLUE GLASS EVERY TWENTY MINUTES TO DETERMINE SIZE AND TEXTURE OF BATCH AND OTHER VARIABLES. FAN IN FRONT COOLS WORKERS AS THEY CONDUCT REPAIRS. FURNACE TEMPERATURE AT 1572 DEGREES FAHRENHEIT. - Chambers-McKee Window Glass Company, Furnace No. 2, Clay Avenue Extension, Jeannette, Westmoreland County, PA

150

Reheating in the presence of inhomogeneous noise  

SciTech Connect

Explosive particle production due to parametric resonance is a crucial feature of reheating in inflationary cosmology. Coherent oscillations of the inflaton field lead to a periodically varying mass in the evolution equation of matter and gravitational fluctuations and often induce a parametric resonance instability. In a previous paper [V. Zanchin {ital et al.}, Phys. Rev. D {bold 57}, 4651 (1998)] it was shown that homogeneous (i.e. space-independent) noise leads to an increase of the generalized Floquet exponent for all modes, at least if the noise is temporally uncorrelated. Here we extend the results to the physically more realistic case of spatially inhomogeneous noise. We demonstrate{emdash}modulo some mathematical fine points which are addressed in a companion paper{emdash}that the Floquet exponent is a non-decreasing function of the amplitude of the noise. We provide numerical evidence for an even stronger statement, namely that in the presence of inhomogeneous noise, the Floquet exponent of each mode is larger than the maximal Floquet exponent of the system in the absence of noise. {copyright} {ital 1999} {ital The American Physical Society}

Zanchin, V. [Departamento de Fisica, Universidade Federal de Santa Maria, 97119-900, Santa Maria, Rio do Sul (Brazil)] [Departamento de Fisica, Universidade Federal de Santa Maria, 97119-900, Santa Maria, Rio do Sul (Brazil); Maia, A. Jr. [Departamento de Matematica Aplicada, Universidade Estadual de Campinas, 13083 - 970, Campinas, Sao Paulo (Brazil)] [Departamento de Matematica Aplicada, Universidade Estadual de Campinas, 13083 - 970, Campinas, Sao Paulo (Brazil); Craig, W. [Mathematics Department and Lefschetz Center for Dynamical Systems, Brown University, Providence, Rhode Island 02912 (United States)] [Mathematics Department and Lefschetz Center for Dynamical Systems, Brown University, Providence, Rhode Island 02912 (United States); Brandenberger, R. [Physics Department, Brown University, Providence, Rhode Island 02912 (United States)] [Physics Department, Brown University, Providence, Rhode Island 02912 (United States)

1999-07-01

151

Inflation and Reheating in Spontaneously Generated Gravity  

E-print Network

Inflation is studied in the context of induced gravity (IG) $\\gamma \\sigma^2 R$, where $R$ is the Ricci scalar, $\\sigma$ a scalar field and $\\gamma$ a dimensionless constant, and diverse symmetry-breaking potentials $V(\\sigma)$ are considered. In particular we compared the predictions for Landau-Ginzburg (LG) and Coleman-Weinberg (CW) type potentials and their possible generalizations with the most recent data. We find that large field inflation generally leads to fewer constraints on the parameters and the shape of the potential whereas small field inflation is more problematic and, if viable, implies more constraints, in particular on the parameter $\\gamma$. We also examined the reheating phase and obtained an accurate analytical solution for the dynamics of inflaton and the Hubble parameter by using a multiple scale analysis (MSA). The solutions were then used to study the average expansion of the Universe, the average equation of state for the scalar field and both the perturbative and resonant decays of ...

Cerioni, A; Tronconi, A; Venturi, G

2010-01-01

152

Inflation and reheating in spontaneously generated gravity  

SciTech Connect

Inflation is studied in the context of induced gravity (IG) {gamma}{sigma}{sup 2}R, where R is the Ricci scalar, {sigma} a scalar field and {gamma} a dimensionless constant, and diverse symmetry-breaking potentials V({sigma}) are considered. In particular we compared the predictions for Landau-Ginzburg and Coleman-Weinberg type potentials and their possible generalizations with the most recent data. We find that large field inflation generally leads to fewer constraints on the parameters and the shape of the potential whereas small field inflation is more problematic and, if viable, implies more constraints, in particular, on the parameter {gamma}. We also examined the reheating phase and obtained an accurate analytical solution for the dynamics of the inflaton and the Hubble parameter by using a multiple scale analysis. The solutions were then used to study the average expansion of the Universe, the average equation of state for the scalar field and both the perturbative and resonant decays of the inflaton field.

Cerioni, A.; Tronconi, A.; Venturi, G. [Dipartimento di Fisica, Universita degli Studi di Bologna, via Irnerio, 46-I-40126 Bologna (Italy); INFN, Sezione di Bologna, via Irnerio 46, I-40126 Bologna (Italy); Finelli, F. [INAF/IASF Bologna, Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna, via Gobetti 101, I-40129 Bologna (Italy); INFN, Sezione di Bologna, via Irnerio 46, I-40126 Bologna (Italy)

2010-06-15

153

Analysis of standard reference materials after microwave-oven digestion in open vessels using graphite furnace atomic absorption spectrophotometry and Zeeman-effect background correction  

Microsoft Academic Search

Heating-covered teflon digestion vials located inside a reheatable container in the presence of different acid mixtures with microwave oven dissolve the metals from biological and environmental certified reference materials. Pb, Cd, Cu, Mn and Fe from the dissolved samples are determined by graphite furnace atomic absorption spectrophotometry and Zeeman-effect background correction. The method allows the treatment of about 100 samples

D. Chakraborti; M. Burguera; J. L. Burguera

1993-01-01

154

High Temperature Transparent Furnace Development  

NASA Technical Reports Server (NTRS)

This report describes the use of novel techniques for heat containment that could be used to build a high temperature transparent furnace. The primary objective of the work was to experimentally demonstrate transparent furnace operation at 1200 C. Secondary objectives were to understand furnace operation and furnace component specification to enable the design and construction of a low power prototype furnace for delivery to NASA in a follow-up project. The basic approach of the research was to couple high temperature component design with simple concept demonstration experiments that modify a commercially available transparent furnace rated at lower temperature. A detailed energy balance of the operating transparent furnace was performed, calculating heat losses through the furnace components as a result of conduction, radiation, and convection. The transparent furnace shells and furnace components were redesigned to permit furnace operation at at least 1200 C. Techniques were developed that are expected to lead to significantly improved heat containment compared with current transparent furnaces. The design of a thermal profile in a multizone high temperature transparent furnace design was also addressed. Experiments were performed to verify the energy balance analysis, to demonstrate some of the major furnace improvement techniques developed, and to demonstrate the overall feasibility of a high temperature transparent furnace. The important objective of the research was achieved: to demonstrate the feasibility of operating a transparent furnace at 1200 C.

Bates, Stephen C.

1997-01-01

155

Development of Zone Melting Furnace  

Microsoft Academic Search

A mirror furnace (Image Furnace (IMF)) for the First Material Processing Test (FMPT) project had been successfully developed in 1986. The IMF will be launched by the space shuttle 'Endeavor' on September, 1992. Based on the experience of the IMF development, an improved mirror furnace (Zone Melting Furnace (ZMF)) is now being developed as experimental equipment for the Japanese Experiment

Shinichi Yoda; Kiwao Shibukawa; Keishi Murakami; Kazumori Hama; Kiyoshi Tanaka; Takao Yokota; Hiroshi Nishimura; Seiichi Takasu

1992-01-01

156

Crystal Growth Furnace (CGF)  

NASA Technical Reports Server (NTRS)

Crystal Growth Furnace (CGF) without the EAC internal support structure. Flown on USML-1 and USML-2. The Principal Investigators on these flights were: Larson, Lehoczky, Matthiesen, Wiedemeier. Processed 6 samples on USML-1 and 7 samples on USML-2.

1991-01-01

157

Franklin Furnace Archive  

NSDL National Science Digital Library

For those not in the know, the phrase "Franklin Furnace" might sound like a type of 19th century heating device. In fact, the Franklin Furnace organization has been dedicated to the proposition that avant-garde art is a very worthwhile endeavor, and their delightful website presents fine information about their work, and about the world of avant-garde art more generally. Based in the Fort Greene neighborhood of Brooklyn, the organization started their work in 1976, and their website offers a nice timeline and introductory essay that documents their own history. Moving along, visitors will definitely want to look over their "Archives" area, which contain a number of online exhibitions and video interview with artists who have worked with Franklin Furnace over the years. Finally, the site also contains a "Scholarly Stuff" section, which features essays on the Furnace and some of the interesting archival techniques they have used to preserve avant-garde art for future generations.

158

Device and Container for Reheating and Sterilization  

NASA Technical Reports Server (NTRS)

Long-duration space missions require the development of improved foods and novel packages that do not represent a significant disposal issue. In addition, it would also be desirable if rapid heating technologies could be used on Earth as well, to improve food quality during a sterilization process. For this purpose, a package equipped with electrodes was developed that will enable rapid reheating of contents via ohmic heating to serving temperature during space vehicle transit. Further, the package is designed with a resealing feature, which enables the package, once used, to contain and sterilize waste, including human waste for storage prior to jettison during a long-duration mission. Ohmic heating is a technology that has been investigated on and off for over a century. Literature indicates that foods processed by ohmic heating are of superior quality to their conventionally processed counterparts. This is due to the speed and uniformity of ohmic heating, which minimizes exposure of sensitive materials to high temperatures. In principle, the material may be heated rapidly to sterilization conditions, cooled rapidly, and stored. The ohmic heating device herein is incorporated within a package. While this by itself is not novel, a reusable feature also was developed with the intent that waste may be stored and re-sterilized within the packages. These would then serve a useful function after their use in food processing and storage. The enclosure should be designed to minimize mass (and for NASA's purposes, Equivalent System Mass, or ESM), while enabling the sterilization function. It should also be electrically insulating. For this reason, Ultem high-strength, machinable electrical insulator was used.

Sastry, Sudhir K.; Heskitt, Brian F.; Jun, Soojin; Marcy, Joseph E.; Mahna, Ritesh

2012-01-01

159

Skid resistance performance of asphalt wearing courses with electric arc furnace slag aggregates.  

PubMed

Metallurgical slags are by-products of the iron and steel industry and are subdivided into blast furnace slag and steel slag according to the different steel-producing processes. In Greece, slags are mostly produced from steelmaking using the electric arc furnace process, and subsequently are either disposed in a random way or utilized by the cement industry. Steel slag has been recently used, worldwide, as hard aggregates in wearing courses in order to improve the skidding resistance of asphalt pavements. At the Highway Laboratory, Department of Civil Engineering of Aristotle University of Thessaloniki research has been carried out in the field of steel slags, and especially in electric arc furnace (EAF) slag, to evaluate their possible use in highway engineering. In this paper, the recent results of anti-skidding performance of steel slag aggregates in highway pavements are presented. PMID:19423603

Kehagia, Fotini

2009-05-01

160

Influence of reheating on the trispectrum and its scale dependence  

SciTech Connect

We study the evolution of the non-linear curvature perturbation during perturbative reheating, and hence how observables evolve to their final values which we may compare against observations. Our study includes the evolution of the two trispectrum parameters, g{sub NL} and ?{sub NL}, as well as the scale dependence of both f{sub NL} and ?{sub NL}. In general the evolution is significant and must be taken into account, which means that models of multifield inflation cannot be compared to observations without specifying how the subsequent reheating takes place. If the trispectrum is large at the end of inflation, it normally remains large at the end of reheating. In the classes of models we study, it remains very hard to generate ?{sub NL} >> f{sub NL}{sup 2}, regardless of the decay rates of the fields. Similarly, for the classes of models in which g{sub NL} ? ?{sub NL} during slow-roll inflation, we find the relation typically remains valid during reheating. Therefore it is possible to observationally test such classes of models without specifying the parameters of reheating, even though the individual observables are sensitive to the details of reheating. It is hard to generate an observably large g{sub NL} however. The runnings, n{sub f{sub N{sub L}}} and n{sub ?{sub N{sub L}}}, tend to satisfy a consistency relation n{sub ?{sub N{sub L}}} = (3/2)n{sub f{sub N{sub L}}} regardless of the reheating timescale, but are in general too small to be observed for the class of models considered.

Leung, Godfrey; Tarrant, Ewan R. M.; Copeland, Edmund J. [School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG7 2RD (United Kingdom); Byrnes, Christian T., E-mail: ppxgl@nottingham.ac.uk, E-mail: ppxet@nottingham.ac.uk, E-mail: ctb22@sussex.ac.uk, E-mail: ed.copeland@nottingham.ac.uk [Astronomy Centre, University of Sussex, Brighton, BN1 9QH (United Kingdom)

2013-08-01

161

Generation of voltage fluctuations in power systems with DC arc furnaces  

Microsoft Academic Search

There is an increasing use of high-power DC arc furnaces for scrap melting all over the world. Onsite measurements in several steel plants with these furnaces have shown that flicker relevant voltage fluctuations cannot be prevented. The first reason is the time-varying need of reactive power. Also dynamic compensators like TCRs are often not able to avoid considerable flicker, particularly

D. Stade; H. Schau; M. Malsch; J. Hunermund; S. Prinz

1998-01-01

162

Effect of chemical attack and operational parameters on the wear of blast furnace refractories  

Microsoft Academic Search

A survey of refractory behavior in a blast furnace has been made because refractory and furnace design problems associated with iron production may apply to coal gasification units. Iron is made in a cylindrical, refractory lined, steel shell that has an internal height of 80 to 90 feet and an internal diameter at tuyere level of 20 to 45 feet.

1976-01-01

163

The Utilization and Recovery of Energy from Blast Furnaces and Converters  

E-print Network

The Bischoff Blast Furnace Top Gas Process for high pressure blast furnaces is presented as an example of a modern gas treatment process in the iron and steel industry: the work potential of the high pressure top gas is utilized in a plant...

Hegemann, K. R.; Niess, T.; Baare, R. D.

1979-01-01

164

DESTRUCTION AND REMOVAL OF POHCS (PRINCPAL ORGANIC HAZARDOUS CONSTITUENTS) IN IRON MAKING BLAST FURNACES  

EPA Science Inventory

At least one steel company utilizes organic waste liquids as a heat and carbon content source to partially replace the coke that is used to charge the blast furnaces. The waste liquids fed to the blast furnace are likely to contain hazardous constituents. Temperature and residenc...

165

Simultaneous data reconciliation and parameter estimation. Application to a basic oxygen furnace.  

E-print Network

oxygen furnace is a method of primary steelmaking in which carbon-rich molten iron is made into refined minutes. By blowing oxygen through molten pig iron, the carbon content of the alloy is lowered and changes the material into low-carbon steel. The basic oxygen furnace actions are scheduled as follows: molten iron from

Paris-Sud XI, Université de

166

Modelling of a DC arc furnace for optimal integration with the supply system  

SciTech Connect

DC arc furnaces have recently gained increasing favor with steel makers all over the world. DC arc furnaces have advantages over their conventional AC counterparts because of their greater supply-friendly nature. Although DC arc furnaces still generate flicker, the stochastic component in their harmonics are reduced and their demands on the supply network are much more compatible with the supply than that of AC arc furnaces. In spite of the relative advantages, however, the input characteristics of DC furnaces still need to be quantified in order to achieve optimal integration with the supply system. System measurements on a 25 MVA DC arc furnace with its filters are correlated with results obtained by numerical integration, and with that obtained through a frequency-domain analytical model that employs harmonic superposition. The behavior of induction motors is also investigated in this model, when they are subjected to the voltage distortion produced by a DC furnace.

Bekker, J.; Swart, P.H.; Landy, C.F.; Marshall, D.A.

1995-12-31

167

VIEW OF CENTRAL STEAM PLANT IN FOREGROUND, BLAST FURNACES NO.S ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF CENTRAL STEAM PLANT IN FOREGROUND, BLAST FURNACES NO.S 1,2 & 3, AND FLOODED ORE YARD. VIEW FACING EAST. - Pittsburgh Steel Company, Monessen Works, Donner Avenue, Monessen, Westmoreland County, PA

168

Plasma furnace treatment of metallurgical by-product streams  

SciTech Connect

It is a common misconception that plasma furnace technology only has application for exotic and very high temperature processes. With the increasing importance placed on waste minimization and the environmental constraints imposed on heavy metals present in byproducts from mainstream operations, plasma technology is finding widespread application. Tetronics is a premier supplier of plasma tundish heating systems for the steel industry. More recently the company has found growing interest in electric arc furnace dust treatment, lead blast furnace slag treatment and metal recovery, copper, nickel and cobalt scavenging from primary smelter slags, dross treatment, platinum group metals (PGM) recovery from catalysts and vitrification and detoxification of heavy metal contaminated waste byproducts. The principal advantages of the plasma arc technology are the close metallurgical control of the furnace environment, minimal off-gas handling requirements and overall high energy efficiency of the processes. A number of applications in the ferrous and non-ferrous metals industry are described.

Whellock, J.G. [JW Technologies, LLC, Englewood, CO (United States); Heanley, C.P.; Chapman, C.S. [Tetronics Ltd., Faringdon (United Kingdom)

1997-12-31

169

Electrical equipment for d-c arc furnaces  

SciTech Connect

Starting with a d-c ladle furnace in 1986 and using worldwide experience in supplying electrical equipment for more than 30 electrical steel plants, Siemens commissioned their first 70-Mw d-c arc furnace at the end of 1992. This article is divided into three parts: Siemens experience with their first d-c furnace: current improvements; and future considerations. Siemens first electrical installation for a d-c furnace has been in successful operation for more than a year. In spite of the special new construction of the thyristor rectifiers and the new digital open and closed-loop controls for this furnace, there have been no electrical failures. For new facilities, electrical components have been optimized based on the experience gained, taking into account the rapid innovations currently taking place. They are rated to accommodate the higher current requirements when graphite electrodes with a diameter of 800 mm or larger are available for the single electrode furnace or for a twin-electrode single shell furnace.

Schnapperelle, J. [Siemens AG, Erlangen (Germany); Gandhi, V. [Siemens Energy and Automation, Inc., Alpharetta, GA (United States)

1995-09-01

170

METALLURGICAL CHARACTERISTICS OF THE MEFOS 3 MW DC ARC FURNACE  

Microsoft Academic Search

Over the past twenty years the 3 MW DC arc furnace at MEFOS has been frequently used for development of new processes. These processes include recovery of valuable metals from slag, sludge and dust from steel and other metallurgical industry, treatment of ashes from power plant and incinerators, smelting reduction of minerals and zinc recovery from EAF dust. The process

G. Ye; J. Alexis; E. Burström

2004-01-01

171

51. LOOKING NORTHWEST FROM THE CLARK AVENUE BRIDGE. BLAST FURNACES ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

51. LOOKING NORTHWEST FROM THE CLARK AVENUE BRIDGE. BLAST FURNACES AND LOWER ORE DOCK CAN BE SEEN AT CENTER; COKE CONVEYOR IS AT LEFT; AT RIGHT, THE TERMINAL TOWER CAN BE SEEN IN THE DISTANCE. - Corrigan, McKinney Steel Company, 3100 East Forty-fifth Street, Cleveland, Cuyahoga County, OH

172

GENERAL VIEW FROM THE SOUTHWEST, SHOWING THE #2 BLAST FURNACE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

GENERAL VIEW FROM THE SOUTHWEST, SHOWING THE #2 BLAST FURNACE IN THE RIGHT; THE CENTRAL COMPLEX WITH STOVES IN THE CENTER. ELECTRICAL POWER HOUSE IS ON THE LEFT BEYOND THE CONVEYOR LIFT. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

173

INTERIOR VIEW SHOWING DISPLAY OF INSIDE OF BLAST FURNACE AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR VIEW SHOWING DISPLAY OF INSIDE OF BLAST FURNACE AND MACHINERY AND ARTIFACTS INCLUDING A STEAM ENGINE HUB MADE AT THE BRIERFIELD ROLLING MILL (INSCRIBED C.C. HUCKABEE AND DATED 1863) AND OTHER STEAM ENGINES. - Iron & Steel Museum of Alabama, 12632 Confederate Pkwy., Bucksville, Tuscaloosa County, AL

174

INTERIOR OF NO. 2 OPEN HEARTH WEST OF FORMER FURNACE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR OF NO. 2 OPEN HEARTH WEST OF FORMER FURNACE NO.25 IN VICINITY OF MIXERS (MACK HEMP) LADLE #1 DETAIL. - Jones & Laughlin Steel Corporation, Pittsburgh Works, Morgan Billet Mill Engine, 550 feet north of East Carson Street, opposite South Twenty-seventh Street, Pittsburgh, Allegheny County, PA

175

INTERIOR OF NO. 2 OPEN HEARTH WEST OF FORMER FURNACE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR OF NO. 2 OPEN HEARTH WEST OF FORMER FURNACE NO. 25 IN VICINITY OF MIXERS (MACK HEMP) LADLE #2. - Jones & Laughlin Steel Corporation, Pittsburgh Works, Morgan Billet Mill Engine, 550 feet north of East Carson Street, opposite South Twenty-seventh Street, Pittsburgh, Allegheny County, PA

176

INTERIOR OF NO. 2 OPEN HEARTH WEST OF FORMER FURNACE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR OF NO. 2 OPEN HEARTH WEST OF FORMER FURNACE NO. 25 IN VICINITY OF MIXERS, LOOKING NW. - Jones & Laughlin Steel Corporation, Pittsburgh Works, Morgan Billet Mill Engine, 550 feet north of East Carson Street, opposite South Twenty-seventh Street, Pittsburgh, Allegheny County, PA

177

INTERIOR OF NO. 2 OPEN HEARTH WEST OF FORMER FURNACE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR OF NO. 2 OPEN HEARTH WEST OF FORMER FURNACE NO. 25 IN VICINITY OF MIXERS (MACK HEMP) LADLE DETAIL. - Jones & Laughlin Steel Corporation, Pittsburgh Works, Morgan Billet Mill Engine, 550 feet north of East Carson Street, opposite South Twenty-seventh Street, Pittsburgh, Allegheny County, PA

178

Northwest view of rotary hearth furnace of the no. 2 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Northwest view of rotary hearth furnace of the no. 2 seamless line in bays 17 and 18 of the main pipe mill building. - U.S. Steel National Tube Works, Skelp Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

179

Southwest view of rotary hearth furnace of the no. 2 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Southwest view of rotary hearth furnace of the no. 2 seamless line in bays 17 and 18 of the main pipe mill building. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

180

Northwest view of rotary hearth furnace of the no. 2 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Northwest view of rotary hearth furnace of the no. 2 seamless line in bays 17 and 18 of the main pipe mill building. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

181

Southwest view of rotary hearth furnace of the no. 2 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Southwest view of rotary hearth furnace of the no. 2 seamless line in bays 17 and 18 of the main pipe mill building. - U.S. Steel National Tube Works, Skelp Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

182

CLOSEUP AERIAL VIEW OF BLAST FURNACES 1 & 2. SHARED ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

CLOSE-UP AERIAL VIEW OF BLAST FURNACES 1 & 2. SHARED CAST HOUSE LIES IN BETWEEN TWO SKIP INCLINES. HIP ROOF AT RIGHT COVERS BLOWING ENGINE HOUSE. VIEW FACING NORTH. - Pittsburgh Steel Company, Monessen Works, Donner Avenue, Monessen, Westmoreland County, PA

183

VIEW FROM THE SOUTH OF THE #1 BLAST FURNACE WITH ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW FROM THE SOUTH OF THE #1 BLAST FURNACE WITH SKIP HOIST AND DUST CATCHER. STOCK BINS FOR RAW MATERIALS ARE IN THE FOREGROUND, THE #2 CASTING SHED BEYOND. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

184

36. View from southwest of No. 2 Furnace skiphoist with ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

36. View from southwest of No. 2 Furnace skip-hoist with skip-hoist engine house in left corner and dust catcher in background. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

185

VIEW FROM THE EAST, SHOWING THE #2 BLAST FURNACE WITH ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW FROM THE EAST, SHOWING THE #2 BLAST FURNACE WITH SKIP HOIST, DUST CATCHER AND STOCK BINS FOR RAW MATERIALS IN THE FOREGROUND. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

186

VIEW OF THE #2 BLAST FURNACE FROM THE EAST, SHOWING ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF THE #2 BLAST FURNACE FROM THE EAST, SHOWING SKIP HOIST, DUST CATCHER AND STOCK BINS IN THE FOREGROUND. #2 CASTING SHED IS TO THE LEFT, HOT BLAST MAIN IS ON THE RIGHT. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

187

Interior of shop, detail of charging machine Bethlehem Steel ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior of shop, detail of charging machine - Bethlehem Steel Corporation, South Bethlehem Works, Tool Steel-Electric Furnace Shop, Along Lehigh River, North of Fourth Street, West of Minsi Trail Bridge, Bethlehem, Northampton County, PA

188

West façade of shop building, looking east Bethlehem Steel ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

West façade of shop building, looking east - Bethlehem Steel Corporation, South Bethlehem Works, Tool Steel-Electric Furnace Shop, Along Lehigh River, North of Fourth Street, West of Minsi Trail Bridge, Bethlehem, Northampton County, PA

189

Entropy mode loops and cosmological correlations during perturbative reheating  

NASA Astrophysics Data System (ADS)

Recently, it has been shown that during preheating the entropy modes circulating in the loops, which correspond to the inflaton decay products, meaningfully modify the cosmological correlation functions at superhorizon scales. In this paper, we determine the significance of the same effect when reheating occurs in the perturbative regime. In a typical two scalar field model, the magnitude of the loop corrections are shown to depend on several parameters like the background inflaton amplitude in the beginning of reheating, the inflaton decay rate and the inflaton mass. Although the loop contributions turn out to be small as compared to the preheating case, they still come out larger than the loop effects during inflation.

Kaya, Ali; Seyma Kutluk, Emine

2015-01-01

190

Improved graphite furnace atomizer  

DOEpatents

A graphite furnace atomizer for use in graphite furnace atomic absorption spectroscopy is described wherein the heating elements are affixed near the optical path and away from the point of sample deposition, so that when the sample is volatilized the spectroscopic temperature at the optical path is at least that of the volatilization temperature, whereby analyteconcomitant complex formation is advantageously reduced. The atomizer may be elongated along its axis to increase the distance between the optical path and the sample deposition point. Also, the atomizer may be elongated along the axis of the optical path, whereby its analytical sensitivity is greatly increased.

Siemer, D.D.

1983-05-18

191

Scale formation and descaling in hot rolling of low carbon steel  

NASA Astrophysics Data System (ADS)

In this research, the effects of gas composition, elapsed time of reaction and temperature on scale formation and descaling of low carbon steel were investigated and results were discussed from the viewpoint of the phase composition of the scales, oxidation rates, oxidation mechanisms, adhesion, fracture mechanics, porosity and residual scale. The phase composition and morphology of scales grown under conditions similar to those of reheating furnaces were analyzed. Low carbon steel was oxidized over the temperature range 1000-1250°C in gas mixtures of O 2-CO2-H2O-N2, O2-H 2O-N2 and O2-CO2-N2. The mole fraction of each phase, wustite (FeO), magnetite (Fe3O 4) and hematite (Fe2O3) was determined by the direct comparison method Two types of scales were observed. The first type was a crystalline scale with an irregular outer surface composed mostly of wustite, and a negligible amount of magnetite. The second type was the classical three-layer scale composed of wustite, magnetite and hematite. In general, the experiments showed that the furnace atmosphere, oxidation time and temperature influence the phase composition of the scales. Low carbon steel was oxidized in air over the temperature range 600-1200°C for 120 s to approximate the formation of secondary and tertiary scale in hot rolling. The mole fraction of wustite, magnetite and hematite was determined by the direct comparison method The phase composition of the scales changed with temperature and time. During the initial 30 s of oxidation, wustite was the predominant phase in the temperature range 800-1200°C, and as oxidation proceeded, the percentages of magnetite and hematite increased. In addition, the texture of the scales was investigated by orientation imaging microscopy (OIM); it was found that temperature influences the texture of the scales. The experiments indicated that 850°C is the ideal temperature for the finishing mill in order to reduce surface defects and work roll wear. The adhesion of scales formed in air on low carbon steel in continuous heating and isothermal conditions was investigated with a four-point bending test. The separation (crack) always occurred inside the scale indicating that the strength of the scale is lower than the strength of the scale/steel interface. It was found that scale adhesion is related to scale porosity, blister formation and stresses acting in the scale. A spallation process was observed when cooling from 800°C to room temperature. The microscopic observations revealed that spallation followed route 1 "strong interface and weak oxide." Low carbon steel was oxidized over the temperature range 1050-1250°C in O2-CO2H2O-N2 gas mixtures in order to study the hydraulic descaling process. The oxidation times were 15-120 min. and the scales were 130-2000 mum thick. The experimental parameters were chosen to approximate scale formation under conditions similar to those of reheating furnaces. In the hydraulic descaling tests, two modes of scale removal were observed. In the first mode, observed in classical three-layer scales that developed an inner porous layer with low or medium porosity, the horizontal undercutting occurred at the boundary of the inner porous layer and dense scale. The second mode was observed in classical three-layer scales that developed an inner porous layer with high porosity and in crystalline scales. In the second mode, the horizontal undercutting occurred at the first plane of large pores relative to the scale/steel interface. In general, the experiments showed that scale morphology controlled the removability of scale.

Basabe Mancheno, Vladimir Vinicio

192

Minimization of Blast furnace Fuel Rate by Optimizing Burden and Gas Distribution  

SciTech Connect

The goal of the research is to improve the competitive edge of steel mills by using the advanced CFD technology to optimize the gas and burden distributions inside a blast furnace for achieving the best gas utilization. A state-of-the-art 3-D CFD model has been developed for simulating the gas distribution inside a blast furnace at given burden conditions, burden distribution and blast parameters. The comprehensive 3-D CFD model has been validated by plant measurement data from an actual blast furnace. Validation of the sub-models is also achieved. The user friendly software package named Blast Furnace Shaft Simulator (BFSS) has been developed to simulate the blast furnace shaft process. The research has significant benefits to the steel industry with high productivity, low energy consumption, and improved environment.

Dr. Chenn Zhou

2012-08-15

193

Saugus Iron Works Blast Furnace  

USGS Multimedia Gallery

A view of the Saugus Iron Works blast furnace, which smelted the iron from limonite, an iron ore. The limonite formed in nearby bogs, and was heated in the blast furnace until the iron melted and ran out the bottom of the furnace....

194

Microstructural Evolution in Power Plant Steels  

E-print Network

, heat energy from fuel combustion or nuclear fission is used to produce jets of steam. The kinetic Steels Pump Cooling water Cooling water Electrical output Condenser Reheat Coal Boiler Superheater Ash HP energy of the steam is converted to electrical energy by a system of turbines and a generator. Figure 2

Cambridge, University of

195

Strengthen flame stability during the furnace`s load decrease  

SciTech Connect

This paper presents the result of the study of the coal combustion characteristic and flame stability during the load decrease of PCFF (corner burner arrangement). Considering the relation between flame stability and furnace load during the furnace load change, some method must be used to strengthen the pulverized coal ignition and combustion for the furnace to maintain the flame stability especially for the furnace which fires low rank anthracite. Experimental results show that when the furnace load decreased, the temperature distribution in furnace decreased and the flame stability in furnace had changed because of the load changing. This paper also introduces a new pulverized coal burner: Bluff-body with cavity burner. According to the result of application of this burner, this kind of pulverized coal burner can improve the coal ignition and combustion efficiency. Especially for low load operation of furnace the bluff-body with cavity burner has demonstrated its ability in strengthening coal ignition and improving the flame stability for furnace operation. Experimental results show that using bluff-body with cavity burner, the lowest load for furnace fired bituminous is 40% MCR and 50% MCr for low rank anthracite (V{sup r} < 12%, A{sup f} > 45%). This burner has simple structure and is very easy to set up for furnace.

Zhang Zhiguo; Sun Xuexin; Li Fujin; Qiu Jihua; Chen Gang [HuaZhong Univ. of Science and Technology, Wuhan, Hubei (China)

1996-12-31

196

1. Copy of Drawing, 'American Steel & Wire Co., Central ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Copy of Drawing, 'American Steel & Wire Co., Central Furnace Works -- Sketch of Plant Showing Tracks & Buildings, 1913, Revised 3/10/31.' Drawing courtesy United States Steel Corporation, Lorain, Ohio. Credit Berni Rich, Score Photographs, August 1979, for photos 1 through 4 and 7 through 11. - Central Furnaces, 2650 Broadway, east bank of Cuyahoga River, Cleveland, Cuyahoga County, OH

197

2. Copy of Drawing, 'American Steel & Wire Company, Central ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. Copy of Drawing, 'American Steel & Wire Company, Central Furnaces & Docks, General Plan of Works Showing Trestle, 1-3-39.' Drawing courtesy of United States Steel Corporation, Lorain, Ohio. - Central Furnaces, 2650 Broadway, east bank of Cuyahoga River, Cleveland, Cuyahoga County, OH

198

High Efficiency Furnace  

SciTech Connect

Disclosed is a dwelling furnace having at least one clam-shell type primary heat exchanger in parallel orientation with a secondary heat exchanger, both the primary and secondary heat exchangers being vertically oriented relative to a furnace housing and parallel to the flow of air to be heated. The primary heat exchanger has a combustion chamber in the lower end thereof, and the lower end of the secondary heat exchanger exhausts into a tertiary heat exchanger oriented approximately perpendicular to the primary and secondary heat exchangers and horizontally relative to the housing, below the combustion chambers of the primary heat exchangers and below the exhaust outlet of the secondary heat exchanger. The tertiary heat exchanger includes a plurality of condensation tubes for retrieving the latent heat of condensation of the combustion gases. The furnace further comprises an induced draft blower for drawing combustion gases through the heat exchangers and inducting sufficient air to the combustion chamber of the primary heat exchanger for efficient combustion.

Hwang, K. S.; Koestler, D. J.

1985-08-27

199

High efficiency furnace  

SciTech Connect

Disclosed is a dwelling furnace having at least one clam-shell type primary heat exchanger in parallel orientation with a secondary heat exchanger, both the primary and secondary heat exchangers being vertically oriented relative to a furnace housing and parallel to the flow of air to be heated. The primary heat exchanger has a combustion chamber in the lower end thereof, and the lower end of the secondary heat exchanger exhausts into a tertiary heat exchanger oriented approximately perpendicular to the primary and secondary heat exchangers and horizontally relative to the housing, below the combustion chambers of the primary heat exchangers and below the exhaust outlet of the secondary heat exchanger. The tertiary heat exchanger includes a plurality of condensation tubes for retrieving the latent heat of condensation of the combustion gases. The furnace further comprises an induced draft blower for drawing combustion gases through the heat exchangers and inducting sufficient air to the combustion chamber of the primary heat exchanger for efficient combustion.

Hwang, K. S.; Koestler, D. J.

1985-12-31

200

On-line ultrasonic system for measuring thickness of the copper stave in the blast furnace  

NASA Astrophysics Data System (ADS)

The blast furnace is used make molten iron from sintered ore and the cokes in the steel industry. Recently, the copper stave cooling system placed on inner face of the blast furnace body to protect the steel shell from heat. In the high temperature environment, the wear between the stave and the material makes the cooling stave thinning by the downward movement of the materials in the blast furnace. It was impossible to access the copper stave with the ultrasonic sensor for measuring thickness because the copper stave is covered with the steel shell and there is backing refractory between the stave and the steel shell. The unique ultrasonic sensor which can approach the cooling stave through the cooling line was developed to measure thickness. The thickness can be measured with portable ultrasonic thickness sensor and can be monitored continuously with embedded sensors.

Choi, Sang-Woo; Kim, Dohoon

2012-05-01

201

Effects of Silicon and Furnace Conditions on Hot Shortness  

NASA Astrophysics Data System (ADS)

Residual Cu in scrap based steel manufactured in the Electric Arc Furnace (EAF) leads to a surface cracking phenomenon known as surface hot shortness. Si is known to provide a potential reduction in hot shortness; however, the mechanisms involved are not fully understood for low Si quantities. This study aims to determine a window of Si contents with a given Ni content needed to counteract the negative effects of Sn and Cu to reduce hot shortness and to determine the mechanism. Thermogravimetric Analysis, SEM-EDS, XRD, and TEM were used to study the hot shortness behavior of a Fe alloy containing 0.2% Cu, 0.05% Ni, 0.01% Sn and with varying Si-content (0.02%, 0.1%, 0.15%, and 0.2% Si). It was found that fayalite formation at the metal/oxide interface resulted in a reduction of oxidation and subsequent Cu-rich liquid formation for all Si contents examined. Under isothermal air oxidation experiments, the range of Si contents between 0.1-0.2 wt% Si exhibited a mechanism that was a combination of fayalite formation impeding oxidation as well as occlusion of the Cu-rich liquid due to internal oxidation. This range was acceptable to alleviate hot shortness under these conditions. Following continuous casting, steel undergoes a cooling process known as secondary cooling where water is sprayed on the surface to promote cooling followed by a radiant cooling stage where the steel is cooled in air to room temperature. The secondary cooling regime leads to oxidation of the alloy in an air + water vapor atmosphere. Experiments were completed to determine the effect of the non-isothermal secondary cooling cycle, the effect of water vapor during secondary cooling, and the effect of the radiant cooling regime down to room temperature. In the case of secondary cooling atmospheres, the non-isothermal cooling cycle resulted in a slight increase in liquid quantity and grain boundary penetration as compared to the isothermal heating cycles due to the higher temperatures experienced in the non-isothermal cycle. The addition of water vapor increased the sample oxidation as compared to samples processed in dry atmospheres due to increased scale adherence, scale plasticity, and inward transport of oxygen. The increase in weight gain of the wet atmosphere compared to the dry atmosphere would indicate increased liquid formation at the interface, which did occur in non-Si containing alloys; however, in Si-containing alloys there was also an increased amount of occlusion of Cu and Fe due to increased scale adherence and inward oxidation in the presence of water vapor increasing the amount of internal oxidation. As Si also increases the formation of internal oxides, the amount of occlusion increased with Si content, significantly decreasing the quantity of liquid at the interface and the amount of grain boundary penetration. In the case of the Fe-Cu-Ni-Sn alloy, the secondary cooling cycle with water lead to the formation of many small pools of Cu-rich liquid embedded within the surface of the metal due to oxidation within liquid penetrated grain boundaries. Oxidation in combustion atmospheres was completed to determine the effect of oxygen content on oxidation in reheat furnaces. Combustion atmospheres with 1%, 3%, and 6% excess oxygen were examined isothermally at 1150°C to compare oxidation in combustion atmospheres to oxidation in air atmospheres. The reduction of available oxygen decreased the oxidation rates in the 1% and 3% excess oxygen atmospheres leading to a reduction in the Cu-rich liquid formation therefore reducing the risk of hot shortness as less liquid is present at the metal/oxide interface. The reduction in free oxygen in the atmosphere decreased the rate and amount of oxidation leading to the formation of a non-uniform scale at short times. However, the 6% excess oxygen atmosphere behaved similarly to air due to the formation of a uniform scale indicating that once a uniform scale is formed, the oxygen content in the atmosphere does not significantly alter the hot shortness behavior of the alloy. (Abstract shortened by UMI.).

Sampson, Erica E.

202

Inflation, baryogenesis, and gravitino dark matter at ultralow reheat temperatures  

SciTech Connect

It is quite possible that the reheat temperature of the Universe is extremely low close to the scale of big bang nucleosynthesis, i.e. T{sub R}{approx}1-10 MeV. At such low reheat temperatures generating matter, antimatter asymmetry and synthesizing dark matter particles are challenging issues which need to be addressed within a framework of beyond the standard model physics. In this paper we point out that a successful cosmology can emerge naturally provided the R-parity violating interactions are responsible for the excess in baryons over antibaryons and at the same time they can explain the longevity of dark matter with the right abundance.

Kohri, Kazunori; Sahu, Narendra [Physics Department, Lancaster University, Lancaster, LA1 4YB (United Kingdom); Mazumdar, Anupam [Physics Department, Lancaster University, Lancaster, LA1 4YB (United Kingdom); Niels Bohr Institute, Blegdamsvej-17, Copenhagen, DK-2100 (Denmark)

2009-11-15

203

Carbon-free induction furnace  

SciTech Connect

An induction furnace for melting and casting highly pure metals and alloys such as uranium and uranium alloys in such a manner as to minimize contamination of the melt by carbon derived from the materials and the environment within the furnace. The subject furnace is constructed of carbon free materials and is housed within a conventional vacuum chamber. The furnace comprises a ceramic oxide crucible for holding the charge of metal or alloy. The heating of the crucible is achieved by a plasma-sprayed tungsten susceptor surrounding the crucible which, in turn, is heated by an RF induction coil separated from the susceptor by a cylinder of inorganic insulation. The furnace of the present invention is capable of being rapidly cycled from ambient temperatures to about 1650/sup 0/C for effectively melting uranium and uranium alloys without the attendant carbon contamination problems previously encountered when using carbon-bearing furnace materials.

Holcombe, C.E.; Masters, D.R.; Pfeiler, W.A.

1985-10-29

204

Non-carbon induction furnace  

DOEpatents

The present invention is directed to an induction furnace for melting and casting highly pure metals and alloys such as uranium and uranium alloys in such a manner as to minimize contamination of the melt by carbon derived from the materials and the environment within the furnace. The subject furnace is constructed of non-carbon materials and is housed within a conventional vacuum chamber. The furnace comprises a ceramic oxide crucible for holding the charge of metal or alloys. The heating of the crucible is achieved by a plasma-sprayed tungsten susceptor surrounding the crucible which, in turn, is heated by an rf induction coil separated from the susceptor by a cylinder of inorganic insulation. The furnace of the present invention is capable of being rapidly cycled from ambient temperatures to about 1650/sup 0/C for effectively melting uranium and uranium alloys without the attendant carbon contamination problems previously encountered when using carbon-bearing furnace materials.

Holcombe, C.E.; Masters, D.R.; Pfeiler, W.A.

1984-01-06

205

Steam Cracker Furnace Energy Improvements  

E-print Network

Steam Cracker Furnace Energy Improvements Tim Gandler Energy Coordinator Baytown Olefins Plant, Baytown Tx 2010 Industrial Energy Technology Conference May, 2010 Page 2 ? Baytown Complex ? Steam Cracking to Olefins ? Furnace overview... high temperature to adequately ?crack? ? The lighter the feed the higher the temperature ? Very energy intensive process; furnace fuel accounts for ~60% of plants energy use Ethylene Plant Energy Consumption 60% 5% 35% Fuel Steam Power Quench...

Gandler, T.

206

Severe Maintenance Problems as Your First Indicator of Big Potential Energy Savings  

E-print Network

Throughout 1994 and 1995, Algoma Steel Inc. conducted several modifications to their No.5 Reheat Furnace Combustion Air System during a major rebuild of the furnace. This involved a redesigned five pass recuperator, a replacement section of ductwork...

Kaufman, S. G.; Martin, V.; Lynn, J.

207

Gravitational wave background from reheating after hybrid inflation  

SciTech Connect

The reheating of the Universe after hybrid inflation proceeds through the nucleation and subsequent collision of large concentrations of energy density in the form of bubblelike structures moving at relativistic speeds. This generates a significant fraction of energy in the form of a stochastic background of gravitational waves, whose time evolution is determined by the successive stages of reheating: First, tachyonic preheating makes the amplitude of gravity waves grow exponentially fast. Second, bubble collisions add a new burst of gravitational radiation. Third, turbulent motions finally sets the end of gravitational waves production. From then on, these waves propagate unimpeded to us. We find that the fraction of energy density today in these primordial gravitational waves could be significant for grand unified theory (GUT)-scale models of inflation, although well beyond the frequency range sensitivity of gravitational wave observatories like LIGO, LISA, or BBO. However, low-scale models could still produce a detectable signal at frequencies accessible to BBO or DECIGO. For comparison, we have also computed the analogous gravitational wave background from some chaotic inflation models and obtained results similar to those found by other groups. The discovery of such a background would open a new observational window into the very early universe, where the details of the process of reheating, i.e. the big bang, could be explored. Moreover, it could also serve in the future as a new experimental tool for testing the inflationary paradigm.

Garcia-Bellido, Juan; Figueroa, Daniel G.; Sastre, Alfonso [Departamento de Fisica Teorica, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid, Spain and Instituto de Fisica Teorica CSIC-UAM, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain)

2008-02-15

208

Fate of supersymmetric flat directions and their role in reheating  

SciTech Connect

We consider the role of supersymmetric flat directions in reheating the Universe after inflation. One or more flat directions can develop large vevs during inflation, which can potentially affect reheating by slowing down scattering processes among inflaton decay products or by coming to dominate the energy density of the Universe. Both effects occur only if flat directions are sufficiently long-lived. The computation of their perturbative decay rate, and a simple estimate of their nonperturbative decay have led to the conclusion that this is indeed the case. In contrast, we show that flat directions can decay quickly through nonperturbative channels in realistic models. The mass matrix for minimal supersymmetric standard model (MSSM) excitations around flat directions has nondiagonal entries, which vary with the phase of the (complex) flat directions. The quasiperiodic motion of the flat directions results in a strong parametric resonance, leading to the rapid depletion of the flat direction within its first few rotations. This may preclude any significant role for the flat directions in reheating the Universe after inflation in models in which the inflaton decays perturbatively.

Olive, Keith A. [William I Fine Theoretical Physics Institute, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Peloso, Marco [School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

2006-11-15

209

Multiple reheat helium Brayton cycles for sodium fast reactors  

SciTech Connect

Sodium fast reactors (SFR) traditionally adopt the steam Rankine cycle for power conversion. The resulting potential for water-sodium reaction remains a continuing concern which at least partly delays the SFR technology commercialization and is a contributor to higher capital cost. Supercritical CO2 provides an alternative, but is also capable of sustaining energetic chemical reactions with sodium. Recent development on advanced inert-gas Brayton cycles could potentially solve this compatibility issue, increase thermal efficiency, and bring down the capital cost close to light water reactors. In this paper, helium Brayton cycles with multiple reheat and intercooling states are presented for SFRs with reactor outlet temperatures in the range of 510°C to 650°C. The resulting thermal efficiencies range from 39% and 47%, which is comparable with supercritical recompression CO2 cycles (SCO2 cycle). A systematic comparison between multiple reheat helium Brayton cycle and the SCO2 cycle is given, considering compatibility issues, plant site cooling temperature effect on plant efficiency, full plant cost optimization, and other important factors. The study indicates that the multiple reheat helium cycle is the preferred choice over SCO2 cycle for sodium fast reactors.

Haihua Zhao; Per F. Peterson

2008-07-01

210

Water gas furnace  

SciTech Connect

A water gas furnace comprising an outer container to provide a housing in which coke is placed into its lower part. A water container is placed within the housing. The coke is ignited and heats the water in the container converting it into steam. The steam is ejected into the coke, which together with air, produces water gas. Preferably, pumice stones are placed above the coke. The water gas is accepted into the pores of the pumice stones, where the heated pumice stones ignite the water gas, producing heat. The heat is extracted by a heat exchanger provided about the housing.

Gallaro, C.

1985-12-03

211

Feeder apparatus for melting furnaces, particularly for plasma melting furnaces  

Microsoft Academic Search

The invention comprises a charging apparatus for melting furnaces, especially for plasma melting furnaces, for the continuous melting of preferably prepared aluminum scrap material. With the help of the proposed solution a controlled and regulated supply of the scrap material along with the prevention of a direct application of the plasma arc or other energy sources directly to the material

K. Primke; P. Papsdorf; G. Pohle; K. P. Trautmann

1984-01-01

212

Two chamber reaction furnace  

DOEpatents

A vertical two chamber reaction furnace is described. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700 C and 800 C) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800 to 950 C to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product. 2 figs.

Blaugher, R.D.

1998-05-05

213

A General Viscosity Model for Molten Blast Furnace Slag  

NASA Astrophysics Data System (ADS)

Blast furnace slag is the most abundant slag in the steel industry. Its metallurgical properties are determined to a great extent by its viscosity. Therefore, it is necessary to establish a reliable viscosity model for blast furnace slag. In the current work, a simple, accurate, and physically meaningful viscosity model for a wide composition range of blast furnace slags is developed based on the Vogel-Fulcher-Tammann (VFT) equation: log ? = A + B/( T - C). The model is calibrated by a database containing 365 compositions and 1233 measurements of synthetic and industrial slags. The parameter A has a value of -3.10. The parameters B and C are related to the mass fraction ratio of (CaO + MgO) to (SiO2 + Al2O3) and liquidus temperature of the slag, respectively. Present viscosity model accurately predicts the viscosity of blast furnace slag with relative average error (?) of 0.211 (±0.180) and root mean square error (RMSE) of 0.239 Pa·s. A slight modification of this model can also predict the glass transition temperature of blast furnace slag satisfactorily.

Gan, Lei; Lai, Chaobin

2014-06-01

214

Method of constructing solar furnace  

Microsoft Academic Search

A solar furnace of dish-shaped configuration for the reflection of solar rays toward a heat exchanger through which passes a heated medium is described. The reflective surface of the furnace comprises a multitude of mirror elements incorporated into a fiber glass reinforced plastic structure with each of the mirror elements located so as to reflect rays toward a common focus.

1976-01-01

215

Heat Treatment Procedure Qualification for Steel Castings  

SciTech Connect

Heat treatment practices used by steel foundries have been carefully studied as part of comprehensive heat treatment procedure qualification development trials. These studies highlight the relationships between critical heat treatment process control parameters and heat treatment success. Foundry heat treatment trials to develop heat treatment procedure qualifications have shed light on the relationship between heat treatment theory and current practices. Furnace load time-temperature profiles in steel foundries exhibit significant differences depending on heat treatment equipment, furnace loading practice, and furnace maintenance. Time-temperature profiles of furnace control thermocouples can be very different from the time-temperature profiles observed at the center of casting loads in the furnace. Typical austenitization temperatures and holding times used by steel foundries far exceed what is required for transformation to austenite. Quenching and hardenability concepts were also investigated. Heat treatment procedure qualification (HTPQ) schema to demonstrate heat treatment success and to pre-qualify other alloys and section sizes requiring lesser hardenability have been developed. Tempering success is dependent on both tempering time and temperature. As such, furnace temperature uniformity and control of furnace loading during tempering is critical to obtain the desired mechanical properties. The ramp-up time in the furnace prior to the establishment of steady state heat treatment conditions contributes to the extent of heat treatment performed. This influence of ramp-up to temperature during tempering has been quantified.

Mariol Charles; Nicholas Deskevich; Vipin Varkey; Robert Voigt; Angela Wollenburg

2004-04-29

216

Vitrification of fly ash by swirling-flow furnace  

SciTech Connect

According to the amendment of the Waste Disposal and Public Cleansing Law of 1992, fly ash is regulated as Specially controlled waste and wide attention is now being paid to the melting and vitrification treatment of fly ash, which can reduce overall volume, detoxify and recover sources. Kobe Steel has demonstrated its operation using a swirling-flow furnace and has perfected a vitrification technique. The demonstration test has confirmed stable melting, high decomposition ratio of dioxins and the soundness of the slag. Kobe Steel has successfully developed a new technique for heightening the quality of slag and a new process for the heavy metals recovery from collected dust.

Ito, Tadashi [Kobe Steel Ltd., Nishi, Kobe (Japan). Engineering and Machinery Div.] [Kobe Steel Ltd., Nishi, Kobe (Japan). Engineering and Machinery Div.

1996-12-31

217

Processing electric arc furnace dust into saleable chemical products  

SciTech Connect

The modern steel industry uses electric arc furnace (EAF) technology to manufacture steel. A major drawback of this technology is the production of EAF dust, which is listed by the U.S. Environmental Protection Agency as a hazardous waste under the Resource Conservation and Recovery Act. The annual disposal of approximately 0.65 million tons of EAF dust in the United States and Canada is an expensive, unresolved problem for the steel industry. EAF dust byproducts are generated during the manufacturing process by a variety of mechanisms. The dust consists of various metals (e.g., zinc, lead, cadmium) that occur as vapors at 1,600{degrees}C (EAF hearth temperature); these vapors are condensed and collected in a baghouse. The production of one ton of steel will generate approximately 25 pounds of EAF dust as a byproduct, which is currently disposed of in landfills.

NONE

1998-04-01

218

Precipitation behaviors of X80 acicular ferrite pipeline steel  

NASA Astrophysics Data System (ADS)

The precipitation behaviors of X80 acicular ferrite pipeline steel were investigated by using transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). The results show that dendritic precipitates in the as-cast steel slabs precipitate mainly in grain boundaries, and these dendritic precipitates dissolve and re-precipitate to two kinds of carbonitrides: Ti- and Nb-rich (Ti, Nb)(C, N) carbonitrides during reheating. Four types of precipitates mainly exist in the hot rolled plate: Ti-rich carbonitrides resulted from the dendritic carbonitrides undissolved during the reheating process; Ti-rich carbonitrides re-precipitated along austenite grain boundaries during the reheating process; NbC carbides mainly heterogeneously nucleated on the small pre-existing Nb-rich carbonitrides in the hot rolling process; and NbC carbides precipitated on dislocations during hot rolling.

Zhao, Ai-Min; Wang, Yan; Chen, Yin-Li; Tang, Di; Gao, Xu-Tao; Zuo, Bi-Qiang

2011-06-01

219

High pressure oxygen furnace  

DOEpatents

A high temperature high pressure oxygen furnace having a hybrid partially externally heated construction is disclosed. A metallic bar fabricated from an alloy having a composition of at least 45% nickel, 15% chrome, and 10% tungsten is utilized (the preferred alloy including 55% nickel, 22% chrome, 14% tungsten, 2% molybdenum, 3% iron (maximum) and 5% cobalt (maximum). The disclosed alloy is fabricated into 11/4 inch bar stock and has a length of about 17 inches. This bar stock is gun drilled for over 16 inches of its length with 0.400 inch aperture to define a closed high temperature, high pressure oxygen chamber. The opposite and closed end of the bar is provided with a small support aperture into which both a support and a thermocouple can be inserted. The closed end of the gun drilled bar is inserted into an oven, preferably heated by standard nickel chrome electrical elements and having a heavily insulated exterior.

Morris, Donald E. (Kensington, CA)

1992-01-01

220

High pressure furnace  

DOEpatents

A high temperature high pressure furnace has a hybrid partially externally heated construction. A metallic vessel fabricated from an alloy having a composition of at least 45% nickel, 15% chrome, and 10% tungsten is utilized (the preferred alloy including 55% nickel, 22% chrome, 14% tungsten, 2% molybdenum, 3% iron (maximum) and 5% cobalt (maximum). The disclosed alloy is fabricated into 11/4 or 2 inch, 32 mm or 50 mm bar stock and has a length of about 22 inches, 56 cm. This bar stock has an aperture formed therein to define a closed high temperature, high pressure oxygen chamber. The opposite and closed end of the vessel is provided with a small blind aperture into which a thermocouple can be inserted. The closed end of the vessel is inserted into an oven, preferably heated by standard nickel chrome electrical elements and having a heavily insulated exterior.

Morris, Donald E. (Kensington, CA)

1993-01-01

221

Recombination Induced Softening and Reheating of the Cosmic Plasma  

E-print Network

The atomic recombination process leads to a softening of the matter equation of state as reflected by a reduced generalized adiabatic index, with accompanying heat release. We study the effects of this recombination softening and reheating of the cosmic plasma on the ionization history, visibility function, Cold Dark Matter (CDM) transfer function, and the Cosmic Microwave Background (CMB) spectra. The resulting modifications of the CMB spectrm is 1/10 of WMAP's current error and is comparable to PLANCK's error. Therefore, this effect should be considered when data with higher accuracy are analysed.

Po Kin Leung; Chi-Wang Chan; Ming-Chung Chu

2003-12-10

222

Gas quenching tool steels  

SciTech Connect

Alloy steel parts are increasingly being heat treated in vacuum furnaces using gas overpressure quenching. The maximum gas pressure typically is 6 bar absolute, and nitrogen usually is the quenching gas. This is adequate for through-hardening tools and other parts made of high-speed, hot-work, and, to a limited extent, cold-work steels. However, the quenching speed (cooling rate) is often too low to permit the successful heat treating of: (1) tools and other parts made of medium- and low-alloy steels; (2) large forging and plastics molding dies made of medium-alloy steels; (3) large, densely loaded batches of identical parts; (4) parts made of austenitic steels and alloys that require a rapid quench after they are solution annealed; and (5) cold-work steel tools and other parts having diameters larger than 100mm (4 in.). Oil quenching is required for these applications. However, its use increases the potential for cracking and can cause distortion. To extend gas quenching to these materials, Leybold Durferrit GmbH, Hanau, Germany, has developed a new generation of vacuum furnaces that combines convective heating and high-pressure gas quenching at pressures up to 20 bar (2 MPa, 290 psi).

Heilmann, P. (Leybold Durferrit GmbH, Hanau (Germany)); Zenker, W.R. (Leybold Technologies Inc., Enfield, CT (United States))

1993-02-01

223

Ceramic coating used on MWC furnace walls  

SciTech Connect

Fire-side corrosion of Municipal Waste Combustor (MWC) furnace walls has been a significant problem for these units. This corrosion can take place quite rapidly. Within less than a year major tube failures have occurred. The corrosion mechanisms and history of various units have been well documented previously. The commonly used answer to this corrosion is use of Inconel 625 weld overlay. It is often applied after erection of units, because the corrosion or its location is unforeseen. Two major problems with the Inconel 625 weld overlay is its high initial cost and the subsequent maintenance due to imperfections in the overlay during its application. Now, a thin, ceramic coating has proven its ability to protect the carbon steel tubes and survive the furnace environment. As of April, 1995, it will have about 10 months of service at the SPSA operated MWC plant. Its cost is a fraction of Inconel 625 weld overlay. Since it forms a continuous coating there are very few imperfections in the coating. One key feature of the ceramic coating is its thermal expansion rate is similar to carbon steel. This eliminates flaking of the ceramic coating. A brief review of the SPSA/NNSY Steam/Power Plant operating characteristics is presented. Maps showing loss of metal (based on ultrasonic testing) in a number of units are presented. Then physical and chemical properties of the ceramic coating are discussed. The costs of various alternatives are compared. This ceramic coating will prove to save MWCs millions of dollars. It can be used to go over poor Inconel overlay work.

Parker, P.R. [Southeastern Public Service Authority, Portsmouth, VA (United States); Zvosec, C. [CETEK, Transfer, PA (United States)

1996-12-31

224

Sensitivity analyses of furnace material properties in the Czochralski crystal growth method for silicon  

NASA Astrophysics Data System (ADS)

Reliability of the numerical simulation results strongly depends on the input data, in particular on the thermo-physical properties of the furnace components, e.g. graphite thermal conductivity and steel surface emissivity. Uncertainties are always involved in the measurement of these parameters. A set of global 2D simulations has been carried out in order to investigate the impact of each property on the growth conditions in Czochralski silicon growth furnaces. The results indicate that steel emissivity and felt conductivity have significant impact on the calculated thermal field and energy consumption.

Asadi Noghabi, O. R.; M'Hamdi, M.; Jomâa, M.

2013-01-01

225

Chem I Supplement: Chemistry of Steel Making.  

ERIC Educational Resources Information Center

Provides information about the chemistry of steel making applicable to teaching secondary school science. Generalized chemical reactions describe the manufacture of steel from iron ore. Also discussed are raw materials, processing choices, and how various furnaces (blast, direct reduction, open hearth, basic oxygen, electric) work. (CS)

Sellers, Neal

1980-01-01

226

Aspects of reheating in first-order inflation  

NASA Technical Reports Server (NTRS)

Studied here is reheating in theories where inflation is completed by a first-order phase transition. In the scenarios, the Universe decays from its false vacuum state by bubble nucleation. In the first stage of reheating, vacuum energy is converted into kinetic energy for the bubble walls. To help understand this phase, researchers derive a simple expression for the equation of state of a universe filled with expanding bubbles. Eventually, the bubble walls collide. Researchers present numerical simulations of two-bubble collisions clarifying and extending previous work by Hawking, Moss, and Stewart. The researchers' results indicate that wall energy is efficiently converted into coherent scalar waves. Also discussed is particle production due to quantum effects. These effects lead to the decay of the coherent scalar waves. They also lead to direct particle production during bubble-wall collisions. Researchers calculate particle production for colliding walls in both sine-Gordon and theta (4) theories and show that it is far more efficient in the theta (4) case. The relevance of this work for recently proposed models of first order inflation is discussed.

Watkins, Richard; Widrow, Lawrence M.

1991-01-01

227

Study of hot hardness characteristics of tool steels  

NASA Technical Reports Server (NTRS)

Hardness measurements of tool steel materials in electric furnace at elevated temperatures and low oxygen environment are discussed. Development of equation to predict short term hardness as function of intial room temperature hardness of steel is reported. Types of steel involved in the process are identified.

Chevalier, J. L.; Dietrich, M. W.; Zaretsky, E. V.

1972-01-01

228

OPTIMAL OPERATION OF ELECTRIC ARC FURNACES (EAF) TO MINIMIZE THE GENERATION OF AIR POLLUTANTS AT THE SOURCE  

EPA Science Inventory

The manufacture of steel by electric arc furnaces (EAF) is continuing to increase in usage in the United States with current production estimated to be over 63 million tons per year. The reduction of emissions from steel producers has been slow for two main reasons: the nee...

229

The Impact of Energy Prices on Technology Choice in the United States Steel Industry  

Microsoft Academic Search

In the last 30 years, U.S. steel producers have replaced their aging open hearth steel furnaces with basic oxygen (BOF) or large electric arc furnaces (LEF). This choice of technology creates the opportunity to substitute electricity for fossil fuels. We extend earlier research to investigate whether energy prices affect this type of technology adoption. The econometric model uses the \\

Gale A. Boyd; Stephen H. Karlson

1993-01-01

230

Coal combustion under conditions of blast furnace injection. Final technical report, September 1, 1992--August 31, 1993  

SciTech Connect

A potentially new use for Illinois coal is as a fuel injected into a blast furnace to produce molten iron as the first step in steel production. Because of its increasing cost and decreasing availability, metallurgical coke is now being replaced by coal injected at the tuyere area of the furnace where the blast air enters. The purpose of this study is to evaluate the combustion of coal during the blast furnace injection process and to delineate the optimum properties of the feed coal. This investigation is significant to the use of Illinois coal in that the limited research to date suggests that coals of low fluidity and moderate to high sulfur and chlorine contents are suitable feedstocks for blast furnace injection. During the first phase of this project a number of the objectives were realized, specifically: (1) a blast furnace sampling system was developed and used successfully to collect samples inside an active furnace; (2) two sets of blast furnace samples were collected and petrographic analysis showed that char derived from injected coal is entering the reduction zone of the furnace; (3) a coal/char sampling probe was designed and fabricated; (4) the completion of a program of reactivity experiments on the injected coal char, blast furnace coke and Herrin No. 6 char. The results of the reactivity experiments indicate that Herrin No. 6 coal is similar or even superior to coals now being used in blast furnace injection and that additional testing is warranted.

Crelling, J.C. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Geology; Case, E.R. [Armco, Inc., Middletown, OH (United States). Research and Technology Div.

1993-12-31

231

Fossil fuel furnace reactor  

DOEpatents

A fossil fuel furnace reactor is provided for simulating a continuous processing plant with a batch reactor. An internal reaction vessel contains a batch of shale oil, with the vessel having a relatively thin wall thickness for a heat transfer rate effective to simulate a process temperature history in the selected continuous processing plant. A heater jacket is disposed about the reactor vessel and defines a number of independent controllable temperature zones axially spaced along the reaction vessel. Each temperature zone can be energized to simulate a time-temperature history of process material through the continuous plant. A pressure vessel contains both the heater jacket and the reaction vessel at an operating pressure functionally selected to simulate the continuous processing plant. The process yield from the oil shale may be used as feedback information to software simulating operation of the continuous plant to provide operating parameters, i.e., temperature profiles, ambient atmosphere, operating pressure, material feed rates, etc., for simulation in the batch reactor.

Parkinson, William J. (Los Alamos, NM)

1987-01-01

232

Modeling fuzzy state space of reheater system for simulation and analysis  

NASA Astrophysics Data System (ADS)

Reheater is one of the important heat exchange components in a high capacity power plant of a boiler system. The aim of this study is to improve heat transfer of a reheater system. The method is to maximize steam production and at the same time, keeping variables within constraints. Fuzzy arithmetic is a powerful tool used to solve engineering problems with uncertain parameters. Therefore, in order to determine heat transfer efficiency, the state space of reheater is simulated using fuzzy arithmetic by taking into account the uncertainties in the reheater system. The uncertain model parameters and the model inputs are represented by fuzzy numbers with their shape derived from quasi-Gaussian function. Finally, this paper discusses how the mathematical model can be manipulated in order to produce maximum heat transfer with least loss of energy. Furthermore, the improvement of the reheater efficiency and the quantification of the heat supplied parameters are presented in this paper.

Munirah, W. M. Wan; Ahmad, T.; Ashaari, A.; Abdullah, M. Adib

2014-07-01

233

Variable frequency microwave furnace system  

DOEpatents

A variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency microwave furnace system includes a microwave signal generator or microwave voltage-controlled oscillator for generating a low-power microwave signal for input to the microwave furnace. A first amplifier may be provided to amplify the magnitude of the signal output from the microwave signal generator or the microwave voltage-controlled oscillator. A second amplifier is provided for processing the signal output by the first amplifier. The second amplifier outputs the microwave signal input to the furnace cavity. In the preferred embodiment, the second amplifier is a traveling-wave tube (TWT). A power supply is provided for operation of the second amplifier. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 5 figs.

Bible, D.W.; Lauf, R.J.

1994-06-14

234

Variable frequency microwave furnace system  

DOEpatents

A variable frequency microwave furnace system (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34) for testing or other selected applications. The variable frequency microwave furnace system (10) includes a microwave signal generator (12) or microwave voltage-controlled oscillator (14) for generating a low-power microwave signal for input to the microwave furnace. A first amplifier (18) may be provided to amplify the magnitude of the signal output from the microwave signal generator (12) or the microwave voltage-controlled oscillator (14). A second amplifier (20) is provided for processing the signal output by the first amplifier (18). The second amplifier (20) outputs the microwave signal input to the furnace cavity (34). In the preferred embodiment, the second amplifier (20) is a traveling-wave tube (TWT). A power supply (22) is provided for operation of the second amplifier (20). A directional coupler (24) is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN)

1994-01-01

235

Furnace and Heat Recovery Area Design and Analysis for Conceptual Design of Oxygen-Based PC Boiler  

SciTech Connect

The objective of the furnace and heat recovery area design and analysis task of the Conceptual Design of Oxygen-Based PC Boiler study is to optimize the location and design of the furnace, burners, over-fire gas ports, and internal radiant surfaces. The furnace and heat recovery area were designed and analyzed using the FW-FIRE and HEATEX computer programs. The furnace is designed with opposed wall-firing burners and over-fire air ports. Water is circulated in the furnace by natural circulation to the waterwalls and divisional wall panels. Compared to the air-fired furnace, the oxygen-fired furnace requires only 65% of the surface area and 45% of the volume. Two oxygen-fired designs were simulated: (1) without over-fire air and (2) with 20% over-fire air. The maximum wall heat flux in the oxygen-fired furnace is more than double that of the air-fired furnace due to the higher flame temperature and higher H{sub 2}O and CO{sub 2} concentrations. The coal burnout for the oxygen-fired case is 100% due to a 500 F higher furnace temperature and higher concentration of O{sub 2}. Because of the higher furnace wall temperature of the oxygen-fired case compared to the air-fired case, furnace water wall material was upgraded from carbon steel to T91. The total heat transfer surface required in the oxygen-fired heat recovery area (HRA) is 25% less than the air-fired HRA due to more heat being absorbed in the oxygen-fired furnace and the greater molecular weight of the oxygen-fired flue gas. The HRA tube materials and wall thickness are practically the same for the air-fired and oxygen-fired design since the flue gas and water/steam temperature profiles encountered by the heat transfer banks are very similar.

Andrew Seltzer

2005-01-01

236

Optical emission from a small scale model electric arc furnace in 250-600 nm region.  

PubMed

Optical emission spectroscopy has been for long proposed for monitoring and studying industrial steel making processes. Whereas the radiative decay of thermal excitations is always taking place in high temperatures needed in steel production, one of the most promising environment for such studies are electric arc furnaces, creating plasma in excited electronic states that relax with intense characteristic emission in the optical regime. Unfortunately, large industrial scale electric arc furnaces also present a challenging environment for optical emission studies and application of the method is not straightforward. To study the usability of optical emission spectroscopy in real electric arc furnaces, we have developed a laboratory scale DC electric arc furnace presented in this paper. With the setup, optical emission spectra of Fe, Cr, Cr2O3, Ni, SiO2, Al2O3, CaO, and MgO were recorded in the wavelength range 250-600 nm and the results were analyzed with the help of reference data. The work demonstrates that using characteristic optical emission, obtaining in situ chemical information from oscillating plasma of electric arc furnaces is indeed possible. In spite of complications, the method could possibly be applied to industrial scale steel making process in order to improve its efficiency. PMID:23635185

Mäkinen, A; Niskanen, J; Tikkala, H; Aksela, H

2013-04-01

237

Optical emission from a small scale model electric arc furnace in 250-600 nm region  

NASA Astrophysics Data System (ADS)

Optical emission spectroscopy has been for long proposed for monitoring and studying industrial steel making processes. Whereas the radiative decay of thermal excitations is always taking place in high temperatures needed in steel production, one of the most promising environment for such studies are electric arc furnaces, creating plasma in excited electronic states that relax with intense characteristic emission in the optical regime. Unfortunately, large industrial scale electric arc furnaces also present a challenging environment for optical emission studies and application of the method is not straightforward. To study the usability of optical emission spectroscopy in real electric arc furnaces, we have developed a laboratory scale DC electric arc furnace presented in this paper. With the setup, optical emission spectra of Fe, Cr, Cr2O3, Ni, SiO2, Al2O3, CaO, and MgO were recorded in the wavelength range 250-600 nm and the results were analyzed with the help of reference data. The work demonstrates that using characteristic optical emission, obtaining in situ chemical information from oscillating plasma of electric arc furnaces is indeed possible. In spite of complications, the method could possibly be applied to industrial scale steel making process in order to improve its efficiency.

Mäkinen, A.; Niskanen, J.; Tikkala, H.; Aksela, H.

2013-04-01

238

Coal combustion under conditions of blast furnace injection; [Quarterly] technical report, September 1--November 30, 1993  

SciTech Connect

A potentially new use for Illinois coal is its use as a fuel injected into a blast furnace to produce molten iron as the first step in steel production. Because of its increasing cost and decreasing availability, metallurgical coke is now being replaced by coal injected at the tuyere area of the furnace where the blast air enters. The purpose of this study is to evaluate the combustion of coal during the blast furnace injection process and to delineate the optimum properties of the feed coal. This investigation is significant to the use of Illinois coal in that the limited research to date suggests that coals of low fluidity and moderate to high sulfur and chlorine contents are suitable feedstocks for blast furnace injection. This study is unique in that it will be the first North American effort to directly determine the nature of the combustion of coal injected into a blast furnace. This proposal is a follow-up to one funded for the 1992--1993 period. It is intended to complete the study already underway with the Armco Inc. steel company and to initiate a new cooperative study along somewhat similar lines with the Inland Steel Company. The results of this study will lead to the development of a testing and evaluation protocol that will give a unique and much needed understanding of the behavior of coal in the injection process and prove the potential of Illinois coals f or such use.

Crelling, J.C.

1993-12-31

239

FUGITIVE EMISSIONS FROM INTEGRATED IRON AND STEEL PLANTS  

EPA Science Inventory

The report gives results of an engineering investigation of fugitive (non-ducted) emissions in the iron and steel industry. Operations excluded from the study are coke ovens, basic oxygen furnace (BOF) charging, and blast furnace cast houses. Fugitive emission factors for iron an...

240

Partial oxidation power plant with reheating and method thereof  

DOEpatents

A system and method for generating power having an air compression/partial oxidation system, a turbine, and a primary combustion system. The air compression/partial oxidation system receives a first air stream and a fuel stream and produces a first partially oxidized fuel stream and a first compressed air stream therefrom. The turbine expands the first partially oxidized fuel stream while being cooled by the first compressed air stream to produce a heated air stream. The heated air stream is injected into the expanding first partially oxidized fuel stream, thereby reheating it in the turbine. A second partially oxidized fuel stream is emitted from the turbine. The primary combustion system receives said second partially oxidized fuel stream and a second air stream, combusts said second partially oxidized fuel stream, and produces rotating shaft power and an emission stream therefrom.

Newby, Richard A. (Pittsburgh, PA); Yang, Wen-Ching (Export, PA); Bannister, Ronald L. (Winter Springs, FL)

1999-01-01

241

Partial oxidation power plant with reheating and method thereof  

DOEpatents

A system and method are disclosed for generating power having an air compression/partial oxidation system, a turbine, and a primary combustion system. The air compression/partial oxidation system receives a first air stream and a fuel stream and produces a first partially oxidized fuel stream and a first compressed air stream therefrom. The turbine expands the first partially oxidized fuel stream while being cooled by the first compressed air stream to produce a heated air stream. The heated air stream is injected into the expanding first partially oxidized fuel stream, thereby reheating it in the turbine. A second partially oxidized fuel stream is emitted from the turbine. The primary combustion system receives said second partially oxidized fuel stream and a second air stream, combusts said second partially oxidized fuel stream, and produces rotating shaft power and an emission stream therefrom. 2 figs.

Newby, R.A.; Yang, W.C.; Bannister, R.L.

1999-08-10

242

Natural Inflation from 5D SUGRA and Low Reheat Temperature  

E-print Network

Motivated by BICEP2's recent observation of a possibly large primordial tensor component $r$ of inflationary perturbations, we reanalyse in detail the 5D conformal SUGRA originated natural inflation model of Ref. [1]. The model is a supersymmetric variant of 5D extra natural inflation, also based on a shift symmetry, and leads to the potential of natural inflation. Analysis of the required number of e-foldings (from the CMB observations) points to the necessity of a very weak inflaton decay and low reheating temperature $T_r$. We show that this can be naturally achieved within 5D gauge inflation giving $T_r\\stackrel{<}{_\\sim } O(100)$ GeV. This is realized by coupling the bulk fields, generating the inflaton potential, with brane SM states. Some related theoretical issues of the construction, along with phenomenological and cosmological implications, are also discussed.

Correia, Filipe Paccetti; Tavartkiladze, Zurab

2015-01-01

243

An Improved Nonlinear STATCOM Control for Electric Arc Furnace Voltage Flicker Mitigation  

Microsoft Academic Search

Electric arc furnaces (EAFs) are prevalent in the steel industry to melt iron and scrap steel. EAFs frequently cause large amplitude fluctuations of active and reactive power and are the source of significant power-quality (PQ) disturbances. Static synchronous compensators (STATCOMs) provide a power-electronic-based means of embedded control for reactive power support and PQ improvement. This paper introduces a new nonlinear

Atousa Yazdani; Mariesa L. Crow; J. Guo

2009-01-01

244

Thermodynamic analysis of performance improvement by reheat on the CO2 transcritical power cycle  

NASA Astrophysics Data System (ADS)

The CO2 transcritical rankine power cycle has been widely investigated recently, because of its better temperature glide matching between sensible heat source and working fluid in vapor generator, and its desirable qualities, such as moderate critical point, little environment impact and low cost. A reheat CO2 transcritical power cycle with two stage expansion is presented to improve baseline cycle performance in this paper. Energy and exergy analysis are carried out to investigate effects of important parameters on cycle performance. The main results show that reheat cycle performance is sensitive to the variation of medium pressures and the optimum medium pressures exist for maximizing work output and thermal efficiency, respectively. Reheat cycle is compared to baseline cycle under the same conditions. More significant improvements by reheat are obtained at lower turbine inlet temperatures and larger high cycle pressure. Work output improvement is much higher than thermal efficiency improvement, because extra waste heat is required to reheat CO2. Based on second law analysis, exergy efficiency of reheat cycle is also higher than that of baseline cycle, because more useful work is converted from waste heat. Reheat with two stage expansion has great potential to improve thermal efficiency and especially net work output of a CO2 transcritical power cycle using a low-grade heat source.

Tuo, Hanfei

2012-06-01

245

BLAST FURNACE GRANULAR COAL INJECTION SYSTEM. Final Report Volume 2: Project Performance and Economics  

SciTech Connect

Bethlehem Steel Corporation (BSC) requested financial assistance from the Department of Energy (DOE), for the design, construction and operation of a 2,800-ton-per-day blast furnace granulated coal injection (BFGCI) system for two existing iron-making blast furnaces. The blast furnaces are located at BSC's facilities in Burns Harbor, Indiana. The demonstration project proposal was selected by the DOE and awarded to Bethlehem in November 1990. The design of the project was completed in December 1993 and construction was completed in January 1995. The equipment startup period continued to November 1995 at which time the operating and testing program began. The blast furnace test program with different injected coals was completed in December 1998.

Unknown

1999-10-01

246

Pilot plant production of ferronickel from nickel oxide ores and dusts in a DC arc furnace  

Microsoft Academic Search

Laterites and other oxidized nickel ores constitute a very important part of world-wide nickel reserves. The development of nickel oxide ore smelting has drawn heavily on iron and steel metallurgy. In ferronickel production, the nickel oxide and part of the iron oxide are reduced to metal in an electric furnace to form immiscible layers of slag and metal. The crude

I. J Kotzé

2002-01-01

247

A fault analysis of DC electric arc furnaces with SVC harmonic filters in a minimill plant  

Microsoft Academic Search

This paper proposes the most feasible solution to overcome the failure of the 2nd harmonic filter in the static VAR compensator (SVC) which operates with the DC electric arc furnace (EAF) at Gwangyang Steel Mill in Korea. In order to investigate the causes of this failure, various measurements were carried out on the DC EAF and the main transformer at

Hansang Lee; Gilsoo Jang; Byungmoon Han

2010-01-01

248

Power quality improvement in DC electric arc furnace plants utilizing multi-phase transformers  

Microsoft Academic Search

The conventional feeding systems for DC electric arc furnace steel making plants usually include a 12 pulse rectifier that is fed by ?\\/? and ?\\/Y three phase transformers. In this paper the advantages of applying multi-phase transformers for supplying such loads are evaluated and compared with the traditional power supply systems. It is shown that utilizing multi-phase transformers can lead

Arash Dehestani Kolagar; Abbas Shoulaie

2012-01-01

249

Nitrogen Control in Electric Arc Furnace Steelmaking by DRI (TRP 0009)  

Microsoft Academic Search

Nitrogen is difficult to remove in electric arc furnace (EAF) steelmaking, requiring the use of more energy in the oxygen steelmaking route to produce low-nitrogen steel. The objective of this work was to determine if the injection of directly reduced iron (DRI) fines into EAFs could reduce the nitrogen content by creating fine carbon monoxide bubbles that rinse nitrogen from

Gordon A. Irons

2004-01-01

250

To reheat, or to not reheat: that is the question: The efficacy of a local reheating protocol on mechanisms of cutaneous vasodilatation.  

PubMed

The aim of this study is to determine the effect of repeated bouts of local skin heating on the roles of nitric oxide synthase (NOS) and sympathetic nerves in cutaneous vasodilatation. In 3 repeated-heating protocols skin blood flux of the forearm and leg was measured using laser-Doppler flowmetry and data are presented as cutaneous vascular conductance (CVC; flux/blood pressure). Local heating was performed from 33°C (thermoneutral) to 42°C at 0.5°C·10s(-1), allowed to cool passively for ~60-min, then reheated at the same rate. In protocol 1, CVC was measured in response to repeated heating. In protocol 2, NOS was inhibited with N(G)-nitro-l-arginine methyl ester (L-NAME) and in protocol 3, sympathetic nerve blockade was achieved with bretylium tosylate (BT), both infused via intradermal microdialysis. In protocol 1, there were no differences (P>0.05) in CVC at either the forearm (88±4 vs. 86±4%max) or the leg (97±4 vs. 96±6%max) between heating bouts. In protocol 2, no differences (P>0.05) in CVC were observed between heating bouts at L-NAME treated sites at either the forearm (55±3 vs. 51±4%max) or the leg (71±3 vs. 70±4%max) . In protocol 3, there were differences (P<0.001) between BT treated sites when comparing the first and second bouts of heating for both the forearm (75±3 vs. 88±4%max) and the leg (79±3 vs. 97±4%max). The effect of sympathetic blockade on CVC responses to local heating was abolished following repeated bouts of heating. Consequently, it is our suggestion that when examining mechanisms of skin blood flow control, investigators use single bouts of local heating. PMID:25281012

Del Pozzi, Andrew T; Hodges, Gary J

2015-01-01

251

Wood by-pass furnace  

SciTech Connect

This wood by-pass furnace is designed in such a manner, as to have the oxygen for combustion controlled, to the extent that the wood does not blaze, but only produces red, glowing coals for heating a home, and the outside cover will not burn anyone when touched. It primarily consists of am inside fire chamber of cylindrical shape, to distribute heat to the top, and it includes a top baffle, that extends from the front of the fire chamber, to the rear of the furnace. It further includes the side baffles, to protect the sides of the heat chamber, and smoke and heat travels up and over the top of the top baffle, to the front of the stove or furnace, and passes out an eight inch pipe. The top baffle further serves to condense the black smoke into liquid, which will dry out and will burn in its dry form.

Stephenson, P.S. Sr.

1983-08-30

252

16 CFR Appendix G2 to Part 305 - Furnaces- Electric  

Code of Federal Regulations, 2014 CFR

...2014-01-01 false Furnaces- Electric G2 Appendix G2 to Part 305...to Part 305—Furnaces— Electric Furnace type Range of annual fuel utilization efficiencies (AFUEs) Low High Electric Furnaces—All Capacities...

2014-01-01

253

Waste Heat Recovery – Submerged Arc Furnaces (SAF)  

E-print Network

Submerged Arc Furnaces are used to produce high temperature alloys. These furnaces typically run at 3000°F using high voltage electricity along with metallurgical carbon to reduce metal oxides to pure elemental form. The process as currently...

O'Brien, T.

2008-01-01

254

Transparent furnace made of heat mirror  

Microsoft Academic Search

A new type of transparent furnace was fabricated with a heat mirror, a glass–ceramic (Neoceram-0) coated with an antimony-doped tin oxide (Sb–SnO2) film. It was compared with a gold furnace, which is the usual transparent furnace. Their performance was almost equivalent, so the Sb–SnO2-coated Neoceram is applicable to the transparent furnace.

M. Kojima; F. Takahashi; K. Kinoshita; T. Nishibe; M. Ichidate

2001-01-01

255

Neutralino and gravitino dark matter with low reheating temperature  

NASA Astrophysics Data System (ADS)

We examine a scenario in which the reheating temperature T R after inflation is so low that it is comparable to, or lower than, the freeze out temperature of ordinary WIMPs. In this case the relic abundance of dark matter is reduced, thus relaxing the impact of the usually strong constraint coming from the requirement that the universe does not overclose. We first re-examine the dynamics of freezeout during reheating. Next we study the parameter space of the MSSM with ten free parameters, the Constrained MSSM and the singlino-dominated regions of the Next-to-MSSM. In each case we often find dramatic departures from the usually considered regime of high T R , with important implications for direct detection dark matter searches. In particular, in the MSSM we examine WIMP mass range up to about 5 TeV, and we find large regions of bino dark matter over the whole mass range, and of higgsino dark matter with mass over a similar range but starting from the ˜ 1 TeV value of the standard high T R scenario. We show that the prospects for bino detection strongly depend on T R , while the higgsino is for the most part detectable by future one-tonne detectors. The wino, which is excluded in the standard scenario, becomes allowed again if its mass is roughly above 3 .5 TeV, and can also be partially detectable. In the CMSSM, the bino and higgsino mass ranges become much more constrained although detection prospects remain roughly similar. In the Next-to-MSSM we show that, at low enough T R wide ranges of singlino-dominated parameter space of the model become again cosmologically allowed, although detection prospects remain nearly hopeless. We also study the non-thermal contribution to the DM relic density from direct and cascade decays of the inflaton. Finally, in the framework of the MSSM we consider the case of a gravitino as dark matter. In this case we find strong bounds from overclosure and from Big Bang Nucleosynthesis, and derive lower limits on T R which depend on the gravitino mass and on the nature of the lightest ordinary superpartner.

Roszkowski, L.; Trojanowski, S.; Turzynski, K.

2014-11-01

256

Heat Recovery From Arc Furnaces Using Water Cooled Panels  

E-print Network

, deter ioration, and erosion. Heavy wall seamless steel pipe is cast into each panel to form the water passages. This de sign provides 7 inch thick sections of cast iron that resist damage even when heavy scrap is charged into the furnace. Cooling... exchanger HE-l whose secondary side is connected to the heat/vent units via the glycol distribution piping. The primary water than passes through a water to water heat exchanger HE-2 (whose secondary side is connected to the cooling tower CT...

Darby, D. F.

257

Hopewell Furnace National Historic Site. Teacher's Guide.  

ERIC Educational Resources Information Center

This teacher's guide contains activities to use in conjunction with a site visit to the Hopewell Furnace National Historic Site (Elverson, Pennsylvania). The guide provides diagrams of the furnace, a cold-blast smelting operation, and the furnace operation. It presents a timeline of iron production from ancient times through contemporary times.…

National Park Service (Dept. of Interior), Washington, DC.

258

The Saugus Iron Works Blast Furnace  

USGS Multimedia Gallery

A view of the Saugus Iron Works blast furnace, which smelted the iron from limonite, an iron ore. The limonite formed in nearby bogs, and was heated in the blast furnace until the iron melted and ran out the bottom of the furnace. ...

259

Silicon smelting in a closed furnace  

Microsoft Academic Search

Dow Corning has been working towards the advancement of silicon smelting in a closed furnace over the past four years. A 200 kVA closed furnace pilot plant unit was built to investigate the operating parameters for smelting silicon. The single electrode furnace is operated under totally sealed conditions. The feed from the feed hoppers is fed through air locks to

V. Dosaj; M. D. Brumels; C. M. Haines; J. B. May

1991-01-01

260

Computer simulation of electric multizone tube furnaces  

Microsoft Academic Search

The paper presents the numerical model and computer program of calculations allowing the electric multizone tube furnace to be simulated. The program allows calculation of temperature distribution in thermally unsteady-state status in thermal insulation of the furnace and in the heating chamber. The program also enables the longitudinal distribution of temperature in the furnace to be calculated. The calculations involve

T. Teodorczyk; K. T. Januszkiewicz

1999-01-01

261

PV-5 automatic furnace control  

SciTech Connect

While refurbishing a Harwood Engineering, Inc. designed gas autoclave facility (designated PV-5) for hot isostatic pressing (HIP) of various materials at the Oak Ridge Y-12 Plant, a furnace power supply problem was encountered. One phase of the furnace's variable AC power supply was devastated when a fault condition occurred. In the process of diagnosing the cause of the fault and repairing the AC power supply of the 30KW furnace for the autoclave vessel, a recommendation to replace the existing, outdated 3-phase saturable-core reactor variable power supplies was implemented. Three new Silicon Controlled Rectifier (SCR) phase-angle fired AC power supplies, one for each phase of the 3-phase 480 volt circuit, were installed. To improve operator control over the new power supplies, a new 0--5 mA controller was connected as a slave to a process programmer to automatically heat the furnace according to preprogrammed temperature profiles. Data acquisition of the process parameters was enhanced by the installation of a hybrid strip chart recorder. 4 figs., 4 tabs.

Younkin, J.R.

1991-06-25

262

High temperature transparent furnace development  

Microsoft Academic Search

A prototype transparent furnace was designed, fabricated, and tested at temperatures up to 1473 K. Radiation containment using an outer infrared mirror tube and convection elimination using vacuum insulation reduce electrical power consumption and heat loads on critical components. High vacuum was necessary to eliminate convection; even 0.001% atmosphere pressure caused large convective heat losses. A heat transfer model was

Stephen C. Bates; Kim S. Knight; David W. Yoel

1998-01-01

263

Concrete linings of heating furnaces  

Microsoft Academic Search

The metallurgical and machine-building industries have more than a thousand heating and heat-treatment furnaces lined with refractory parts. The life of the linings is up to 2 years including intermediate repairs of individual elements. The primary reason for the low life of linings is their insufficient structural strength and also failure of refractory parts in periodic sharp heating and cooling.

S. R. Zamyatin

1993-01-01

264

Crystal growth and furnace analysis  

NASA Technical Reports Server (NTRS)

A thermal analysis of Hg/Cd/Te solidification in a Bridgman cell is made using Continuum's VAST code. The energy equation is solved in an axisymmetric, quasi-steady domain for both the molten and solid alloy regions. Alloy composition is calculated by a simplified one-dimensional model to estimate its effect on melt thermal conductivity and, consequently, on the temperature field within the cell. Solidification is assumed to occur at a fixed temperature of 979 K. Simplified boundary conditions are included to model both the radiant and conductive heat exchange between the furnace walls and the alloy. Calculations are performed to show how the steady-state isotherms are affected by: the hot and cold furnace temperatures, boundary condition parameters, and the growth rate which affects the calculated alloy's composition. The Advanced Automatic Directional Solidification Furnace (AADSF), developed by NASA, is also thermally analyzed using the CINDA code. The objective is to determine the performance and the overall power requirements for different furnace designs.

Dakhoul, Youssef M.

1986-01-01

265

High temperature transparent furnace development  

NASA Astrophysics Data System (ADS)

A prototype transparent furnace was designed, fabricated, and tested at temperatures up to 1473 K. Radiation containment using an outer infrared mirror tube and convection elimination using vacuum insulation reduce electrical power consumption and heat loads on critical components. High vacuum was necessary to eliminate convection; even 0.001% atmosphere pressure caused large convective heat losses. A heat transfer model was developed to predict the behavior of the transparent furnace and permit projection of performance improvements resulting from design changes. The mirror tube that reflects infrared radiation and transmits some visible radiation was modified to eliminate radiation absorption in the mirror tube itself. Radiation shields were added to the ends of the furnace to further reduce radiative heat losses. Conductive heat losses were minimized by minimizing solid connections to the cooled furnace ends and by using quartz supports. All components were designed to survive high temperature operation. Extensive experiments were performed with a succession of preliminary prototypes, leading to a final prototype successfully tested at 1473 K.

Bates, Stephen C.; Knight, Kim S.; Yoel, David W.

1998-01-01

266

HRC steel mill project. Volume 2. Final report. Export trade information  

SciTech Connect

The initial step in developing the design for a steel producing facility is the selection of the major processes to be used. This study investigated five steelmaking processes to determine the one(s) best suited for Grasim based on technical and cost performance. The processes were: Electric Arc Furnace; Induction Furnace/BOF; KS Furnace; Cupola; and Submerged Arc. This investigation determined that the electric arc furnace (EAF) was the most suitable melting process for the production of steel using DRI feed stock.

NONE

1995-08-01

267

The effect of globular microstructure size on the mechanical properties in reheating process of aluminum alloys  

NASA Astrophysics Data System (ADS)

One of the important steps in semi-solid forming is the process of reheating raw materials to the semi-solid state. This process is not only necessary to achieve the required semi-solid state of the billet, but also to control the microstructure of the billet. In the reheating process, the globule size is determined by the holding time of the final reheating step. Therefore, some experiments to investigate the relationship between the mechanical properties and the holding time in the last heating step were performed. The alloys used in this experiment were 357, 319, and A390 alloys. The experiments of reheating were performed using an induction heating system with a capacity of 50 kW. This article shows the evolution of the microstructure according to the holding time of the last reheating stage. Furthermore, to evaluate the effect of globule size as determined by holding time of the final reheating step, uniaxial tension tests were performed. The stress-strain curves were plotted according to the holding time, and a relationship between the microstructure and the flow stress of semi-solid material was formulated.

Kang, C. G.; Youn, S. W.; Seo, P. K.

2004-04-01

268

Finite Element Modeling of Reheat Stretch Blow Molding of PET  

NASA Astrophysics Data System (ADS)

Poly (ethylene terephthalate) or PET is a polymer used as a packaging material for consumer products such as beverages, food or other liquids, and in other applications including drawn fibers and stretched films. Key features that make it widely used are its transparency, dimensional stability, gas impermeability, impact resistance, and high stiffness and strength in certain preferential directions. These commercially useful properties arise from the fact that PET crystallizes upon deformation above the glass transition temperature. Additionally, this strain-induced crystallization causes the deformation behavior of PET to be highly sensitive to processing conditions. It is thus crucial for engineers to be able to predict its performance at various process temperatures, strain rates and strain states so as to optimize the manufacturing process. In addressing these issues; a finite element analysis of the reheat blow molding process with PET has been carried out using ABAQUS. The simulation employed a constitutive model for PET developed by Dupaix and Boyce et al.. The model includes the combined effects of molecular orientation and strain-induced crystallization on strain hardening when the material is deformed above the glass transition temperature. The simulated bottles were also compared with actual blow molded bottles to evaluate the validity of the simulation.

Krishnan, Dwarak; Dupaix, Rebecca B.

2004-06-01

269

Reheating the universe after multi-field inflation  

SciTech Connect

We study in detail (p)reheating after multi-field inflation models with a particular focus on N-flation. We consider a variety of different couplings between the inflatons and the matter sector, including both quartic and trilinear interactions with a light scalar field. We show that the presence of multiple oscillating inflatons makes parametric resonance inefficient in the case of the quartic interactions. Moreover, perturbative processes do not permit a complete decay of the inflaton for this coupling. In order to recover the hot big bang, we must instead consider trilinear couplings. In this case we show that strong nonperturbative preheating is possible via multi-field tachyonic resonance. In addition, late-time perturbative effects do permit a complete decay of the condensate. We also study the production of gauge fields for several prototype couplings, finding similar results to the trilinear scalar coupling. During the course of our analysis we develop the mathematical theory of the quasi-periodic Mathieu equation, the multi-field generalization of the Floquet theory familiar from preheating after single field inflation. We also elaborate on the theory of perturbative decays of a classical inflaton condensate, which is applicable in single-field models also.

Braden, Jonathan; Kofman, Lev; Barnaby, Neil, E-mail: jbraden@physics.utoronto.ca, E-mail: barnaby@cita.utoronto.ca [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George St., Toronto, ON M5S 3H8 (Canada)

2010-07-01

270

Reheating-volume measure in the string theory landscape  

SciTech Connect

I recently proposed the ''reheating-volume'' (RV) prescription as a possible solution to the measure problem in ''multiverse'' cosmology. The goal of this work is to extend the RV measure to scenarios involving bubble nucleation, such as the string theory landscape. In the spirit of the RV prescription, I propose to calculate the distribution of observable quantities in a landscape that is conditioned in probability to nucleate a finite total number of bubbles to the future of an initial bubble. A general formula for the relative number of bubbles of different types can be derived. I show that the RV measure is well defined and independent of the choice of the initial bubble type, as long as that type supports further bubble nucleation. Applying the RV measure to a generic landscape, I find that the abundance of Boltzmann brains is always negligibly small compared with the abundance of ordinary observers in the bubbles of the same type. As an illustration, I present explicit results for a toy landscape containing four vacuum states, and for landscapes with a single high-energy vacuum and a large number of low-energy vacua.

Winitzki, Sergei [Department of Physics, Ludwig-Maximilians University, Munich (Germany)

2008-12-15

271

Prospects of determination of reheating temperature after inflation by DECIGO  

NASA Astrophysics Data System (ADS)

If the tensor-to-scalar ratio r of cosmological perturbations takes a large value r˜ 0.1, which may be inferred from the recent BICEP2 result, we can hope to determine thermal history, in particular, the reheating temperature, T_R, after inflation by space-based laser interferometers. It is shown that upgraded and upshifted versions of DECIGO may be able to determine T_R if it lies in the range 6× 10^6< T_R < 5× 10^7GeV and 3× 10^7< T_R< 2× 10^8GeV, respectively. Although these ranges include predictions of some currently plausible inflation models, because each specification can probe T_R of a range of at most a decade, we should determine the specifications of DECIGO taking full account of the constraints on inflation models to be obtained by near-future observations of temperature anisotropy and B-model polarization of the cosmic microwave background radiation.

Kuroyanagi, Sachiko; Nakayama, Kazunori; Yokoyama, Jun'ichi

2015-01-01

272

A Feasibility Study for Recycling Used Automotive Oil Filters In A Blast Furnace  

SciTech Connect

This feasibility study has indicated that of the approximately 120,000 tons of steel available to be recycled from used oil filters (UOF's), a maximum blast furnace charge of 2% of the burden may be anticipated for short term use of a few months. The oil contained in the most readily processed UOF's being properly hot drained and crushed is approximately 12% to 14% by weight. This oil will be pyrolized at a rate of 98% resulting in additional fuel gas of 68% and a condensable hydrocarbon fraction of 30%, with the remaining 2% resulting as carbon being added into the burden. Based upon the writer's collected information and assessment, there appears to be no operational problems relating to the recycling of UOF's to the blast furnace. One steel plant in the US has been routinely charging UOF's at about 100 tons to 200 tons per month for many years. Extensive analysis and calculations appear to indicate no toxic consideration as a result of the pyrolysis of the small contained oil ( in the 'prepared' UOFs) within the blast furnace. However, a hydrocarbon condensate in the ''gasoline'' fraction will condense in the blast furnace scrubber water and may require additional processing the water treatment system to remove benzene and toluene from the condensate. Used oil filters represent an additional source of high quality iron units that may be effectively added to the charge of a blast furnace for beneficial value to the operator and to the removal of this resource from landfills.

Ralph M. Smailer; Gregory L. Dressel; Jennifer Hsu Hill

2002-01-21

273

Coal combustion under conditions of blast furnace injection. Technical report, March 1, 1994--May 31, 1994  

SciTech Connect

A potentially new use for Illinois coal is its use as a fuel injected into a blast furnace to produce molten iron as the first step in steel production. Because of its increasing cost and decreasing availability, metallurgical coke is now being replaced by coal injected at the tuyere area of the furnace where the blast air enters. The purpose of this study is to evaluate the combustion of coal during the blast furnace injection process and to delineate the optimum properties of the feed coal. This investigation is significant to the use of Illinois coal in that the limited research to date suggests that coals of low fluidity and moderate to high sulfur and chlorine contents are suitable feedstocks for blast furnace injection. This proposal is a follow-up to one funded for the 1992-93 period. It is intended to complete the study already underway with the Armco Inc. Steel Company and to initiate a new cooperative study along somewhat similar lines with the Inland Steel Company. The results of this study will lead to the development of a testing and evaluation protocol that will give a unique and much needed understanding of the behavior of coal in the injection process and prove the potential of Illinois coals for such use. During this quarter samples of two feed coals and the IBCSP 112 (Herrin No. 6) were prepared for reactivity testing and compared to blast furnace coke, and char fines taken from an active blast furnace. As the initial part of a broad reactivity analysis program, these same samples were also analyzed on a thermogravimetric analyzer (TGA) to determine their combustion and reactivity properties.

Crelling, J.C. [Southern Illinois Univ., Carbondale, IL (United States)

1994-09-01

274

Direct current, closed furnace silicon technology  

SciTech Connect

The dc closed furnace technology for smelting silicon offers technical operating challenges, as well as, economic opportunities for off-gas recovery, reduced electrode consumption, reduced reductant oxidation losses, reduced energy consumption, and improved silicon recovery. The 10 mva dc closed furnace is located in East Selkirk, Manitoba. Construction of this pilot plant was started in September 1990. Following successful commissioning of the furnace in 1992, a number of smelting tests have been conducted aimed at optimization of the furnace operation and the raw material mix. The operation of a closed furnace is significantly different from an open furnace operation. The major difference being in the mechanical movement of the mix, off-gas recovery, and inability to observe the process. These differences made data collection and analysis critical in making operating decisions. This closed furnace was operated by computer control (state of the art in the smelling industry).

Dosaj, V.D. [Dow Corning Corp., Midland, MI (United States); May, J.B. [Dow Corning Corp., Freeland, MI (United States); Arvidson, A.N. [Meadow Materials, Manitoba (Canada)

1994-05-01

275

Peculiarity of the process of quenching carburized steel parts  

SciTech Connect

The intensive steel quenching methods are widely used for the thermohardening of alloy and high alloy steels. In the present work an opportunity for the application of intensive steel quenching methods with reference to carburized steel parts is justified. Advantages and disadvantages are discussed. The advantages consist of an opportunity to reduce the duration of the carburizing process, increase the quality and durability of carburized steel parts, achieve additional strengthening of material and optimize the distribution of residual stresses after quenching carburized steel parts. Disadvantages consist of a necessity to modify continuous gas carburizing furnaces.

Kobasko, N.I. [National Academy of Science, Kiev (Ukraine). Engineering Thermophysics Inst.

1995-12-31

276

Blast furnace coke quality in relation to petroleum coke addition  

SciTech Connect

The incorporation of petroleum coke as an additive in industrial coking coal blends is a practice often used by steel companies. A suitable blast furnace coke produced by replacing part of the coking coal blend with a suitable petroleum coke (addition of 5 to 15%), was made by Great Lakes Carbon Corporation and successfully tested at several blast furnaces. This coke had lower reactivity, less ash and slightly higher sulfur content than coke made without the addition of petroleum coke. In contrast with these results, it has been reported in a BCRA study that additions of petroleum coke to a strong coking coal, above 5 wt%, increased coke reactivity. These differences may be explained on the basis of the coal or blend characteristics to which petroleum coke is added. Petroleum coke addition seems to give better results if the coal/blend has high fluidity. The present situation in Spain is favorable for the use of petroleum coke. So, a study of laboratory and semi-industrial scale was made to assess the possibility of using petroleum coke as an additive to the typical industrial coal blend coked by the Spanish Steel Company, ENSIDESA. The influence of the petroleum coke particle size was also studied to semi-industrial scale.

Alvarez, R.; Diez, M.A.; Menendez, J.A.; Barriocanal, C.; Pis, J.J. [CSIC, Oviedo (Spain). Inst. Nacional del Carbon; Sirgado, M. [ENSIDESA, Aviles (Spain)

1995-12-01

277

Diagnostics for a waste processing plasma arc furnace (invited) (abstract)  

SciTech Connect

Maintaining the quality of our environment has become an important goal of society. As part of this goal new technologies are being sought to clean up hazardous waste sites and to treat ongoing waste streams. A 1 MW pilot scale dc graphite electrode plasma arc furnace (Mark II) has been constructed at MIT under a joint program among Pacific Northwest Laboratory (PNL), MIT, and Electro-Pyrolysis, Inc. (EPI)[sup c] for the remediation of buried wastes in the DOE complex. A key part of this program is the development of new and improved diagnostics to study, monitor, and control the entire waste remediation process for the optimization of this technology and to safeguard the environment. Continuous, real time diagnostics are needed for a variety of the waste process parameters. These parameters include internal furnace temperatures, slag fill levels, trace metals content in the off-gas stream, off-gas molecular content, feed and slag characterization, and off-gas particulate size, density, and velocity distributions. Diagnostics are currently being tested at MIT for the first three parameters. An active millimeter-wave radiometer with a novel, rotatable graphite waveguide/mirror antenna system has been implemented on Mark II for the measurement of surface emission and emissivity which can be used to determine internal furnace temperatures and fill levels. A microwave torch plasma is being evaluated for use as a excitation source in the furnace off-gas stream for continuous atomic emission spectroscopy of trace metals. These diagnostics should find applicability not only to waste remediation, but also to other high temperature processes such as incinerators, power plants, and steel plants.

Woskov, P.P. (Plasma Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States))

1995-01-01

278

High temperature furnace modeling and performance verifications  

NASA Technical Reports Server (NTRS)

Analytical, numerical, and experimental studies were performed on two classes of high temperature materials processing sources for their potential use as directional solidification furnaces. The research concentrated on a commercially available high temperature furnace using a zirconia ceramic tube as the heating element and an Arc Furnace based on a tube welder. The first objective was to assemble the zirconia furnace and construct parts needed to successfully perform experiments. The 2nd objective was to evaluate the zirconia furnace performance as a directional solidification furnace element. The 3rd objective was to establish a data base on materials used in the furnace construction, with particular emphasis on emissivities, transmissivities, and absorptivities as functions of wavelength and temperature. A 1-D and 2-D spectral radiation heat transfer model was developed for comparison with standard modeling techniques, and were used to predict wall and crucible temperatures. The 4th objective addressed the development of a SINDA model for the Arc Furnace and was used to design sample holders and to estimate cooling media temperatures for the steady state operation of the furnace. And, the 5th objective addressed the initial performance evaluation of the Arc Furnace and associated equipment for directional solidification. Results of these objectives are presented.

Smith, James E., Jr.

1992-01-01

279

Fabrication of high nitrogen austenitic stainless steels with excellent mechanical and pitting corrosion properties  

Microsoft Academic Search

A series of high nitrogen austenitic stainless steels were successfully developed with a pressurized electroslag remelting furnace. Nitride additives and deoxidizer were packed into the stainless steel pipes, and then the stainless steel pipes were welded on the surface of an electrode with low nitrogen content to prepare a compound electrode. Using Si3N4 as a nitrogen alloying source, the silicon

Hua-bing Li; Zhou-hua Jiang; Yang Cao; Zu-rui Zhang

2009-01-01

280

Structural characteristics and hydration kinetics of modified steel slag  

SciTech Connect

This study investigates the structural characteristics and hydration kinetics of modified basic oxygen furnace steel slag. The basic oxygen furnace steel slag (BOFS) was mixed with electric arc furnace steel slag (EAFS) in appropriate ratios and heated again at high temperature in the laboratory. The mineralogical and structural characteristics of both BOFS and modified steel slag (MSS) were characterized by X-ray diffraction, optical microscopy, scanning electron microscopy, Raman and Fourier transform infrared spectroscopies. The results show that modification increases alite content in MSS and decreases alite crystal size with the formation of C{sub 6}AF{sub 2}. One more obvious heat evolution peak appears in MSS's heat-flow rate curves in comparison to BOFS, becoming similar to that of typical Portland cement paste. As a result, its cementitious activity is much improved.

Li Jianxin; Yu Qijun; Wei Jiangxiong, E-mail: jxwei@scut.edu.cn; Zhang Tongsheng

2011-03-15

281

Ferrosilicon smelting in a direct current furnace  

SciTech Connect

The present invention is a process for smelting ferrosilicon alloy. The process comprises adding a carbon source and tailings comprising oxides of silicon and iron to a substantially closed furnace. Heat is supplied to the furnace by striking a direct current arc between a cathode electrode and an anode functional hearth. In a preferred embodiment of the present invention, the cathode electrode is hollow and feed to the substantially closed furnace is through the hollow electrode.

Dosaj, Vishu D. (Midland, MI); May, James B. (Midland, MI)

1992-12-29

282

Crystal growth furnace with trap doors  

NASA Technical Reports Server (NTRS)

An improved furnace is provided for growing crystalline bodies from a melt. The improved furnace is characterized by a door assembly which is remotely controlled and is arranged so as to selectively shut off or permit communication between an access port in the furnace enclosure and a hot zone within that enclosure. The invention is especially adapted to facilitate use of crystal growing cartridges of the type disclosed in U.S. Pat. No. 4,118,197.

Sachs, Emanual M. (Inventor); Mackintosh, Brian H. (Inventor)

1982-01-01

283

Measurement of airflow in residential furnaces  

SciTech Connect

In order to have a standard for furnaces that includes electricity consumption or for the efficiency of furnace blowers to be determined, it is necessary to determine the airflow of a furnace or furnace blower. This study focused on airflow testing, in order to determine if an existing test method for measuring blower airflow could be used to measure the airflow of a furnace, under conditions seen in actual installations and to collect data and insights into the operating characteristics of various types of furnace blowers, to use in the analysis of the electricity consumption of furnaces. Results of the measured airflow on furnaces with three types of blower and motor combinations are presented in the report. These included: (1) a forward-curved blower wheel with a typical permanent split capacitor (PSC) motor, (2) a forward-curved blower wheel with an electronically-commutated motor (ECM), and (3) a prototype blower, consisting of a backward-inclined blower wheel matched to an ECM motor prototype, which is being developed as an energy-saving alternative to conventional furnace blowers. The testing provided data on power consumption, static and total pressure, and blower speed.

Biermayer, Peter J.; Lutz, James; Lekov, Alex

2004-01-24

284

A Study of Structure Formation and Reheating in the D3/D7 Brane Inflation Model  

E-print Network

We study the spectrum of cosmological fluctuations in the D3/D7 brane inflationary universe with particular attention to the parametric excitation of entropy modes during the reheating stage. The same tachyonic instability which renders reheating in this model very rapid leads to an exponential growth of entropy fluctuations during the preheating stage which in turn induces a large contribution to the large-scale curvature fluctuations. We take into account the effects of long wavelength quantum fluctuations in the matter fields. As part of this work, we perform an analytical analysis of the reheating process. We find that the initial stage of preheating proceeds by the tachyonic instability channel. An upper bound on the time it takes for the energy initially stored in the inflaton field to convert into fluctuations is obtained by neglecting the local fluctuations produced during the period of tachyonic decay and analyzing the decay of the residual homogeneous field oscillations, which proceeds by parametric...

Brandenberger, Robert H; Davis, Anne-Christine

2008-01-01

285

Acoustic emission monitoring for inspection of seam-welded hot reheat piping in fossil power plants  

NASA Astrophysics Data System (ADS)

Although failure of the seam weld on reheat steam piping has been an infrequent occurrence, such failure is still a major safety concern for fossil plant operations. EPRI has provided guidelines for a piping management program base don periodic inspection. More recently, EPRI has also sponsored research to develop inspection techniques to both improve the quality and reduce the cost of piping inspections. Foremost in this research has been the use of acoustic emission (AE) techniques to detect crack damage in seam welds. AE has the substantial cost advantages of both allowing inspection without full removal of the thermal insulation on the reheat piping and making short-re- inspection intervals practical. This paper reviews the EPRI guidelines for performing an AE inspection on seam-welded hot reheat piping.

Rodgers, John M.; Morgan, Bryan C.; Tilley, Richard M.

1996-11-01

286

Development of High-Temperature and Low-Oxygen Atmosphere Controlled Furnace and Its Application to Metal Jointing Technology  

NASA Astrophysics Data System (ADS)

Metal joining by brazing or diffusion bonding is typically performed at temperatures around 1573K. At such temperatures, atmosphere or vacuum furnaces are required to avoid metal oxidation while heating. The drawbacks of atmosphere furnaces are their use of explosive gases such as hydrogen and the inability of using metal conveyor belts above 1423K. In this study, a non-oxidizing continuous furnace that uses only inert gas atmospheres was developed to work in conjunction with a carbon/carbon composite conveyor belt that can be used up to 2873K, and was used in metal joining processes. The development of the furnace, its working principle and features, and its application in brazing and diffusion bonding of stainless steel are reported with supporting experimental data.

Kanda, Kiichi; Hashimoto, Hiromu

287

Conservation, An In-Plant Energy Resource  

E-print Network

Potential energy savings of 90 billion cubic feet of natural gas per year on existing facilities in basic steel alone are attainable through retrofitting and improvement in operations. Areas covered include reheat furnaces, soaking pits, cover...

Skudneski, L. A.

1980-01-01

288

Coal combustion under conditions of blast furnace injection. [Quarterly] technical report, 1 December 1993--28 February 1994  

SciTech Connect

A potentially new use for Illinois coal is its use as a fuel injected into a blast furnace to produce molten iron as the first step in steel production. Because of its increasing cost and decreasing availability, metallurgical coke is now being replaced by coal injected at the tuyere area of the furnace where the blast air enters. The purpose of this study is to evaluate the combustion of coal during the blast furnace injection process and to delineate the optimum properties of the feed coal. This proposal is a follow-up to one funded for the 1992--1993 period. It is intended to complete the study already underway with the Armco Inc. Steel Company and to initiate a new cooperative study along somewhat similar lines with the Inland Steel Company. The results of this study will lead to the development of a testing and evaluation protocol that will give a unique and much needed understanding of the behavior of coal in the injection process and prove the potential of Illinois coals for such use. During this quarter a sample of the feed coal that is being used for injection into the No. 7 Blast Furnace of Inland Steel has been analyzed petrographically and compared to both the Herrin No. 6 coal and Armco feed coal. Additional characterization is underway and an advanced program of pyrolysis and reactivity testing has been initiated.

Crelling, J.C. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Geology

1994-06-01

289

POLLUTION EFFECTS OF ABNORMAL OPERATIONS IN IRON AND STEEL MAKING. VOLUME 1. TECHNICAL REPORT  

EPA Science Inventory

The report is the first in a six-volume series considering abnormal operating conditions (AOCs) in the primary section (sintering, blast furnace ironmaking, open hearth, electric furnace, and basic oxygen steelmaking) of an integrated iron and steel plant. Pollution standards, ge...

290

Silicon smelting in a closed furnace  

SciTech Connect

Dow Corning has been working towards the advancement of silicon smelting in a closed furnace over the past four years. A 200 kVA closed furnace pilot plant unit was built to investigate the operating parameters for smelting silicon. The single electrode furnace is operated under totally sealed conditions. The feed from the feed hoppers is fed through air locks to the furnace. The off-gas from the furnace, consisting of by-product CO as well as volatiles from the feeds, pass through a venturi scrubber, where water is introduced to scrub out the fume from the furnace and cool the gas. The mixed scrubber water and off-gas pass into a centrifugal mist eliminator where the water and fume disengage from the gas. The fume slurry is passed through bag filters where the fume is separated from the water. The clean off-gas from the furnace was evaluated for its calorific value and evaluated for conversion to useful products. A number of silicon smelting tests were conducted during this program. Various levels of charcoal and coal mixtures were evaluated to determine the optimum mix. A low volatile coal was preferred over typical Blue Gem coal. The coal amount in the mix was maximized without compromising the smelting performance. A raw material mix consisting of 30% charcoal and 70% low volatile coal was determined to be an optimum mix for closed furnace operation. Silicon recoveries in the low nineties were demonstrated using this mix. Four quartz sources were also evaluated in the closed furnace. The closed furnace operation for silicon smelting was identified to offer significant advantages over an open furnace from the standpoint of reduced carbon oxidation losses, electrode consumption, electrical energy consumption and silicon yield improvement. Other advantages in addition to process off-gas recovery included improved safety from reduced heat and fume exposure, and improved pollution control to the environment. 1 ref.

Dosaj, V.; Brumels, M.D.; Haines, C.M.; May, J.B. [Dow Corning Corp., Midland, MI (United States)

1991-12-31

291

Silicon smelting in a closed furnace  

SciTech Connect

Dow Corning has been working towards the advancement of silicon smelting in a closed furnace over the past four years. A 200 kVA closed furnace pilot plant unit was built to investigate the operating parameters for smelting silicon. The single electrode furnace is operated under totally sealed conditions. The feed from the feed hoppers is fed through air locks to the furnace. The off-gas from the furnace, consisting of by-product CO as well as volatiles from the feeds, pass through a venturi scrubber, where water is introduced to scrub out the fume from the furnace and cool the gas. The mixed scrubber water and off-gas pass into a centrifugal mist eliminator where the water and fume disengage from the gas. The fume slurry is passed through bag filters where the fume is separated from the water. The clean off-gas from the furnace was evaluated for its calorific value and evaluated for conversion to useful products. A number of silicon smelting tests were conducted during this program. Various levels of charcoal and coal mixtures were evaluated to determine the optimum mix. A low volatile coal was preferred over typical Blue Gem coal. The coal amount in the mix was maximized without compromising the smelting performance. A raw material mix consisting of 30% charcoal and 70% low volatile coal was determined to be an optimum mix for closed furnace operation. Silicon recoveries in the low nineties were demonstrated using this mix. Four quartz sources were also evaluated in the closed furnace. The closed furnace operation for silicon smelting was identified to offer significant advantages over an open furnace from the standpoint of reduced carbon oxidation losses, electrode consumption, electrical energy consumption and silicon yield improvement. Other advantages in addition to process off-gas recovery included improved safety from reduced heat and fume exposure, and improved pollution control to the environment. 1 ref.

Dosaj, V.; Brumels, M.D.; Haines, C.M.; May, J.B. (Dow Corning Corp., Midland, MI (United States))

1991-01-01

292

Vertical two chamber reaction furnace  

DOEpatents

A vertical two chamber reaction furnace is disclosed. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700 and 800 C) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800 to 950 C to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product. 2 figs.

Blaugher, R.D.

1999-03-16

293

19. Inside the cast house at Furnace A. Molten iron ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

19. Inside the cast house at Furnace A. Molten iron flowed into eight ladles. The furnace was cast (or tapped) six times each day. - Central Furnaces, 2650 Broadway, east bank of Cuyahoga River, Cleveland, Cuyahoga County, OH

294

Recent developments in electric arc furnace operation  

Microsoft Academic Search

The provision of water cooled electric arc furnace walls and roofs, the increased use of iron pellets in the raw material charge, the use of solid state devices in electrode drive systems and the application of digital control are discussed. Integration of computer control of the separate aspects of arc furnace operation into an optimal direct digital control strategy for

A. S. Morris

1983-01-01

295

Developmental testing of a programmable multizone furnace  

NASA Technical Reports Server (NTRS)

A multizone furnace was evaluated for its potential utilization for process experimentation on board the Space Shuttle. A temperature gradient can be created through the use of a series of connected temperature zones and can be translated by the coordinated sequencing of zone temperatures. The Bridgman-Stockbarger thermal configuration for directional solidification was implemented so that neither the sample nor furnace was translated. The thermal behavior of the furnace was measured and characterized. Limitations due to both thermal and electronic (computer) factors are identified. The results indicate that the multizone design is limited to low temperature gradients because of the indirect furnace-to-sample thermal coupling needed to blend the discrete thermal zones. The multizone furnace design inherently consumes more power than a similar (two temperature) conventional Bridgman type directional solidification furnace because every zone must be capable of the high cooling rates needed to produce the maximum desired temperature drop. Typical achievable static temperature gradients for the furnace tested were between 6 and 75 C/in. The maximum gradient velocity was approximately 10 in./hr. Several aspects of the tested system could be improved, but the dependence of the multizone design on high heat loss will limit Space Shuttle applications in the form tested unless additional power is available. The multizone furnace offers great flexibility but requires a high level of operator understanding for full advantage to be obtained.

Ting, E. Y.; Larson, D. J., Jr.

1986-01-01

296

Optimized Design of a Furnace Cooling System  

E-print Network

This paper presents a case study of manufacturing furnace optimized re-design. The bottleneck in the production process is the cooling of heat treatment furnaces. These ovens are on an approximate 24-hour cycle, heating for 12 hours and cooling...

Morelli, F.; Bretschneider, R.; Dauzat, J.; Guymon, M.; Studebaker, J.; Rasmussen, B. P.

2013-01-01

297

Developing composite furnace module cooling systems  

Microsoft Academic Search

The composite furnace module cooling system is designed to provide an essentially uniform hot-face temperature that is low enough to promote the formation of a protective accretion layer for furnace containment. A minimal amount of copper is used to ensure that the installation of the modules will not significantly alter the process heat balance during normal operation. The modules have

A. K. Kyllo; N. B. Gray; D. Papazoglou; B. J. Elliot

2000-01-01

298

FURNACE COOLING TECHNOLOGY IN PYROMETALLURGICAL PROCESSES  

Microsoft Academic Search

Reliable furnace cooling technology is a domain of increasing concern to the pyrometallurgical industry as it can significantly increase process intensities, productivity and campaign times of furnaces. Although there are many advantages in using cooling systems, they also impose a variety of problems mainly related to safety, heat losses and sustainability of the operations. The choice of cooling system is

Karel Verscheure; Andrew K. Kyllo; Andreas Filzwieser; Bart Blanpain; Patrick Wollants

299

ANALYSIS OF EMISSIONS FROM RESIDENTIAL OIL FURNACES  

EPA Science Inventory

The paper gives results of a series of emission tests on a residential oil furnace to determine emissions from two types of burners. umber of analyses were performed on the emissions, including total mass, filterable particulate, total oil furnaces tested by the EPA in Roanoke, V...

300

Smoothness evaluation of clean furnace blacks  

Microsoft Academic Search

The use of furnace process carbon blacks in semiconductive shields for cable is well known. For medium- to high-voltage power cables, furnace carbon black-filled semiconducting materials are used most notably to prevent a partial discharge at the surface between the conductor and the insulation or the insulation and the insulation shield layers. The author shows that two critical carbon black

Steven L. Greene

1994-01-01

301

Existing and prospective blast-furnace conditions  

SciTech Connect

Blast-furnace conditions are investigated by means of a multizone model. The expected performance of prospective technologies is assessed, as well as the trends in blast-furnace processes. The model permits the identification of means of overcoming practical difficulties.

I.G. Tovarovskii; V.I. Bol'shakov; V.P. Lyalyuk; A.E. Merkulov; D. V. Pinchuk [Ukrainian Academy of Sciences, Dnepropetrovsk (Ukraine). Institute of Ferrous Metallurgy

2009-07-15

302

A simple high-pressure furnace for liquid-encapsulated Bridgman\\/Stockbarger crystal growth  

Microsoft Academic Search

This paper describes a simple, internally-heated high pressure furnace for liquid-encapsulated synthesis and melt growth at temperatures up to 1200 C and pressures up to 100 bar. The hot zone is contained in a 102-mm-ID x 127-mm-OD x 508-mm-long tubular vessel made of 304-series stainless steel. The vessel is externally water cooled and has self-sealing O-ring end closures. A Kanthal

T. F. Ciszek; C. D. Evans

1988-01-01

303

Optical Sensors for Post Combustion Control in Electric Arc Furnace Steelmaking (TRP 9851)  

Microsoft Academic Search

Working in collaboration with Stantec Global Technologies, Process Metrix Corporation, and The Timken Company, Sandia National Laboratories constructed and evaluated a novel, laser-based off-gas sensor at the electric arc furnace facility of Timken's Faircrest Steel Plant (Canton, Ohio). The sensor is based on a mid-infrared tunable diode laser (TDL), and measures the concentration and temperature of specific gas species present

Sarah W. Allendorf; David K. Ottesen; Robert W. Green; Donald R. Hardesty; Robert Kolarik; Howard Goodfellow; Euan Evenson; Marshall Khan; Ovidiu Negru; Michel Bonin; Soren Jensen

2003-01-01

304

Optical cavity furnace for semiconductor wafer processing  

DOEpatents

An optical cavity furnace 10 having multiple optical energy sources 12 associated with an optical cavity 18 of the furnace. The multiple optical energy sources 12 may be lamps or other devices suitable for producing an appropriate level of optical energy. The optical cavity furnace 10 may also include one or more reflectors 14 and one or more walls 16 associated with the optical energy sources 12 such that the reflectors 14 and walls 16 define the optical cavity 18. The walls 16 may have any desired configuration or shape to enhance operation of the furnace as an optical cavity 18. The optical energy sources 12 may be positioned at any location with respect to the reflectors 14 and walls defining the optical cavity. The optical cavity furnace 10 may further include a semiconductor wafer transport system 22 for transporting one or more semiconductor wafers 20 through the optical cavity.

Sopori, Bhushan L.

2014-08-05

305

A multi-zone muffle furnace design  

NASA Technical Reports Server (NTRS)

A Multi-Zone Muffle-Tube Furnace was designed, built, and tested for the purpose of providing an in-house experience base with tubular furnaces for materials processing in microgravity. As such, it must not only provide the desired temperatures and controlled thermal gradients at several discrete zones along its length but must also be capable of sustaining the rigors of a Space Shuttle launch. The furnace is insulated to minimize radial and axial heat losses. It is contained in a water-cooled enclosure for purposes of dissipating un-wanted residual heat, keeping the outer surfaces of the furnace at a 'touch-safe' temperature, and providing a rugged housing. This report describes the salient features of the furnace, testing procedures and results, and concluding remarks evaluating the overall design.

Rowe, Neil D.; Kisel, Martin

1993-01-01

306

Numerical simulation of coupled two-phase gas/liquid flow in an electric arc furnace  

SciTech Connect

The importance of an electric arc furnace (EAF) process in the production of steel has increased over the last decade. Currently, this process is used for 40 percent of the raw steel produced, and it accounts for the consumption of 20 TWhr of electrical energy. Furthermore, projections indicate that the EAF production process will account for 42 percent and 45 percent, respectively, of the total steel production in 1995 and 2000. The increasing cost of electricity, and the demand to produce higher quality grades of steel, mandate a closer inspection of the process. One issue that couple production quality and efficiency, and which is suitable for numerical simulation, is the effect of stirring on bath homogeneity.

Tanski, J.

1993-11-01

307

Method of Making Steel Strapping and Strip  

SciTech Connect

Fact sheet written for the Inventions and Innovation Program about a new method for making steel strapping and strip from rod stock produced from scrap steel. There is a large movement in the American steel industry to utilize more recycled steel. Recycled steel melted in the electric arc furnaces of mini-mills is being used as the source of raw materials for an increasing number of products, largely due to its lower price. However, conventional processes for producing steel strapping and cold-rolled strip steel restrict manufacturers from using more than 50% recycled steel. In addition, steel strapping and cold-rolled strip steel traditionally require many production steps. They are produced from primary steel that has been cast into slab, heated, rolled to achieve the desired thickness, and slit to the desired width. The slitting process produces microcracks along the edge of the strapping or strip, which reduce tensile strength. A new continuous process produces steel strapping and 1/2 inch to 6 inch strip steel from the rod and strip stock made from scrap steel in mini-mills. The new process creates steel strapping and strip with improved strength and quality due to the absence of microcracks caused by the conventional slitting process. The finished product is cheaper because of the lower cost associated with using rod ad lower conversion costs. In addition, the higher tensile strength of the product allows for thinner strapping. The process represents a new approach to producing any steel strapping used for bundling and packaging items for storage or transport. In addition, this innovative new process can be used to produce cold-rolled strip steel, a basic raw material for automobile parts, hardware, office equipment, and many other products.

NONE

1999-12-10

308

WEST (FRONT) OF FURNACE COMPLEX, INCLUDING STACKS, WITH CHARGING BRIDGE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

WEST (FRONT) OF FURNACE COMPLEX, INCLUDING STACKS, WITH CHARGING BRIDGE AND TRESSLE, LOOKING SOUTHEAST. - Tannehill Furnace, 12632 Confederate Parkway, Tannehill Historical State Park, Bucksville, Tuscaloosa County, AL

309

Reheating effects in the matter power spectrum and implications for substructure  

NASA Astrophysics Data System (ADS)

The thermal and expansion history of the Universe before big bang nucleosynthesis is unknown. We investigate the evolution of cosmological perturbations through the transition from an early matter era to radiation domination. We treat reheating as the perturbative decay of an oscillating scalar field into relativistic plasma and cold dark matter. After reheating, we find that subhorizon perturbations in the decay-produced dark matter density are significantly enhanced, while subhorizon radiation perturbations are instead suppressed. If dark matter originates in the radiation bath after reheating, this suppression may be the primary cutoff in the matter power spectrum. Conversely, for dark matter produced nonthermally from scalar decay, enhanced perturbations can drive structure formation during the cosmic dark ages and dramatically increase the abundance of compact substructures. For low reheat temperatures, we find that as much as 50% of all dark matter is in microhalos with M?0.1M? at z?100, compared to a fraction of ˜10-10 in the standard case. In this scenario, ultradense substructures may constitute a large fraction of dark matter in galaxies today.

Erickcek, Adrienne L.; Sigurdson, Kris

2011-10-01

310

Reheating effects in the matter power spectrum and implications for substructure  

SciTech Connect

The thermal and expansion history of the Universe before big bang nucleosynthesis is unknown. We investigate the evolution of cosmological perturbations through the transition from an early matter era to radiation domination. We treat reheating as the perturbative decay of an oscillating scalar field into relativistic plasma and cold dark matter. After reheating, we find that subhorizon perturbations in the decay-produced dark matter density are significantly enhanced, while subhorizon radiation perturbations are instead suppressed. If dark matter originates in the radiation bath after reheating, this suppression may be the primary cutoff in the matter power spectrum. Conversely, for dark matter produced nonthermally from scalar decay, enhanced perturbations can drive structure formation during the cosmic dark ages and dramatically increase the abundance of compact substructures. For low reheat temperatures, we find that as much as 50% of all dark matter is in microhalos with M > or approx. 0.1M{sub +} at z{approx_equal}100, compared to a fraction of {approx}10{sup -10} in the standard case. In this scenario, ultradense substructures may constitute a large fraction of dark matter in galaxies today.

Erickcek, Adrienne L. [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George Street, Toronto, Ontario M5S 3H8 (Canada); Perimeter Institute for Theoretical Physics, 31 Caroline St. N, Waterloo, Ontario N2L 2Y5 (Canada); Sigurdson, Kris [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z1 (Canada)

2011-10-15

311

Effect of storage and subsequent reheating on viability of Listeria monocytogenes on pork scrapple.  

PubMed

We evaluated the fate of Listeria monocytogenes on commercial pork scrapple, a regionally popular, ready-to-eat (RTE) meat. We also conducted an informal survey to address consumer practices for storing and reheating scrapple. Of the 129 consumers who responded to at least one of the eight questions posed in the survey, about half (46.4%; 52 of 112) considered scrapple RTE, the majority (69.7%; 76 of 109) stored it in the refrigerator, and all (100%; 112 of 112) preferred to reheat it prior to consumption. Most respondents (83.9%; 94 of 112) reheated the scrapple by pan frying for 1 to 10 min at medium to high temperature. To study pathogen behavior, slices of pork scrapple were surface inoculated with a five-strain cocktail of L. monocytogenes (ca. 2.0 log CFU/g), vacuum sealed, and stored for up to 60 days. Pathogen levels increased to 8.9, 9.5, and 9.9 log CFU/g after 44 (4 degrees C), 21 (10 degrees C), and 5 (21 degrees C) days, respectively. When slices 1.3 cm (ca. 55 g) and 1.9 cm (ca. 85 g) thick were surface inoculated with L. monocytogenes (ca. 7.0 log CFU/g) and then reheated in a skillet (191 degrees C) for 0.5 to 4 min per side or to target instantaneous internal temperatures of 48.9 to 71.1 degrees C, it was possible to achieve pathogen reductions ranging from ca. 2.2 to 6.5 log CFU/g. These data confirm that in the unlikely event of postprocessing contamination of pork scrapple by L. monocytogenes, proper reheating can appreciably reduce levels of the pathogen before consumption. PMID:20003735

Adekunle, A O; Porto-Fett, A C S; Call, J E; Shoyer, B; Gartner, K; Tufft, L; Luchansky, J B

2009-12-01

312

Unstable Arc Motion in an Atmospheric Pressure Furnace  

NASA Astrophysics Data System (ADS)

Plasma Arc Furnaces are used extensively in metallurgical processing and hazardous waste remediation. Studies of arc equilibrium and stability are being carried out on an experimental 20 kW 250 A DC open air arc at PPPL. Intermittent arc motion in the frequency range of 200-1000 Hz has been observed on a steel and graphite anodes with a graphite cathode, with frequency varying approximately 10% within a burst. Arc motion is typically accompanied by ~10% rms current and ~3% rms voltage fluctuations and sometimes leads to arc extinction. Possible sources of the instability are being investigated, including the cathode jet, arc current, and anode geometry and composition effects. Stability measurements in the arc current, arc length parameter space as well as dependence on anode material and geometry will be compared with theoretical model predictions.

Karasik, Max; Zweben, S. J.

1998-10-01

313

Enriching blast furnace gas by removing carbon dioxide.  

PubMed

Blast furnace gas (BF gas) produced in the iron making process is an essential energy resource for a steel making work. As compared with coke oven gas, the caloric value of BF gas is too low to be used alone as fuel in hot stove because of its high concentrations of carbon dioxide and nitrogen. If the carbon dioxide in BF gas could be captured efficiently, it would meet the increasing need of high caloric BF gas, and develop methods to reusing and/or recycling the separated carbon dioxide further. Focused on this, investigations were done with simple evaluation on possible methods of removing carbon dioxide from BF gas and basic experiments on carbon dioxide capture by chemical absorption. The experimental results showed that in 100 minutes, the maximum absorbed doses of carbon dioxide reached 20 g/100 g with ionic liquid as absorbent. PMID:25078829

Zhang, Chongmin; Sun, Zhimin; Chen, Shuwen; Wang, Baohai

2013-12-01

314

Advanced Automated Directional Solidification Furnace (AADSF)  

NASA Technical Reports Server (NTRS)

The Advanced Automated Directional Solidification Furnace (AADSF) with the Experimental Apparatus Container (EAC) removed flew during the USMP-2 mission. During USMP-2, the AADSF was used to study the growth of mercury cadmium telluride crystals in microgravity by directional solidification, a process commonly used on earth to process metals and grow crystals. The furnace is tubular and has three independently controlled temperature zones . The sample travels from the hot zone of the furnace (1600 degrees F) where the material solidifies as it cools. The solidification region, known as the solid/liquid interface, moves from one end of the sample to the other at a controlled rate, thus the term directional solidification.

1992-01-01

315

Pilot plant testing of Illinois coal for blast furnace injection. Quarterly report, 1 December 1994--28 February 1995  

SciTech Connect

A potentially new use for Illinois coal is its use as a fuel injected into a blast furnace to produce molten iron as the first step in steel production. Because of its increasing cost and decreasing availability, metallurgical coke is now being replaced by coal injected at the tuyere area of the furnace where the blast air enters. The purpose of this study is to evaluate the combustion of Illinois coal in the blast furnace injection process in a new and unique pilot plant test facility. This investigation is significant to the use of Illinois coal in that the limited research to date suggests that coals of low fluidity and moderate to high sulfur and chlorine contents are suitable feedstocks for blast furnace injection. This study is unique in that it is the first North American effort to directly determine the nature of the combustion of coal injected into a blast furnace. This proposal is a follow-up to one funded for the 1993--94 period. It is intended to complete the study already underway with the Armco and Inland steel companies and to demonstrate quantitatively the suitability of both the Herrin No. 6 and Springfield No. 5 coals for blast furnace injection. The main feature of the current work is the testing of Illinois coals at CANMET`s (Canadian Centre for Mineral and Energy Technology) pilot plant coal combustion facility. This facility simulates blowpipe-tuyere conditions in an operating blast furnace, including blast temperature (900{degrees}C), flow pattern (hot velocity 200 m/s), geometry, gas composition, coal injection velocity (34 m/s) and residence time (20 ms). The facility is fully instrumented to measure air flow rate, air temperature, temperature in the reactor, wall temperature, preheater coil temperature and flue gas analysis. During this quarter there were two major accomplishments.

Crelling, J.C.

1995-12-31

316

Regularities of heat transfer in the gas layers of a steam boiler furnace flame. Part II. Gas layer radiation laws and the procedure for calculating heat transfer in furnaces, fire boxes, and combustion chambers developed on the basis of these laws  

NASA Astrophysics Data System (ADS)

The article presents the results stemming from the scientific discovery of laws relating to radiation from the gas layers generated during flame combustion of fuel and when electric arc burns in electric-arc steel-melting furnaces. The procedure for calculating heat transfer in electric-arc and torch furnaces, fire-boxes, and combustion chambers elaborated on the basis of this discovery is described.

Makarov, A. N.

2014-10-01

317

46 CFR 164.009-13 - Furnace calibration.  

Code of Federal Regulations, 2010 CFR

...that the furnace is in good working order. In each calibration the energy input to the furnace is adjusted so that the furnace thermocouple gives a steady reading of 750 ±10 °C. The wall temperature of the furnace tube is then measured by an optical...

2010-10-01

318

Toxic-Waste Disposal by Drain-in-Furnace Technique  

NASA Technical Reports Server (NTRS)

Compact furnace moved from site to site. Toxic industrial waste destroyed using furnace concept developed for disposal of toxic munitions. Toxic waste drained into furnace where incinerated immediately. In furnace toxic agent rapidly drained and destroyed in small combustion chamber between upper and lower layers of hot ceramic balls

Compton, L. E.; Stephens, J. B.; Moynihan, P. I.; Houseman, J.; Kalvinskas, J. J.

1986-01-01

319

Coal combustion under conditions of blast furnace injection. Technical report, 1 December 1992--28 February 1993  

SciTech Connect

A potentially new use for Illinois coal is its use as a fuel injected into a blast furnace to produce molten iron as the first step in steel production. Because of its increasing cost and decreasing availability, metallurgical coke is now being replaced by coal injected at the tuyere area of the furnace where the blast air enters. The purpose of this study is to evaluate the combustion of coal during the blast furnace injection process and to delineate the optimum properties of the feed coal. This investigation is significant to the use of Illinois coal in that the limited research to date suggests that coals of low fluidity and moderate to high sulfur and chlorine contents are suitable feedstocks for blast furnace injection. This proposed study is unique in that it will be the first North American effort to directly determine the nature of the combustion of coal injected into a blast furnace. The Amanda furnace of Armco is the only one in North America currently using coal injection and is, therefore, the only full scale testing facility available. During this quarter complete petrographic analyses of all of the samples so far collected were completed.

Crelling, J.C. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Geology; Case, E.R. [Armco, Inc., Middletown, OH (United States). Research and Technology Div.

1993-05-01

320

Advanced Automated Directional Solidification Furnace (AADSF)  

NASA Technical Reports Server (NTRS)

The Advanced Automated Directional Solidification Furnace (AADSF) with the Experimental Apparatus Container (EAC) attached flew during the USMP-2 mission. This assembly consists of a furnace module, a muffle tube assembly and a translation mechanism which are enclosed in the EAC. During USMP-2, the AADSF was used to study the growth of mercury cadmium telluride crystals in microgravity by directional solidification, a process commonly used on earth to process metals and grow crystals. The furnace is tubular and has three independently controlled temperature zone . The sample travels from the hot zone of the furnace (1600 degrees F) where the material solidifies as it cools. The solidification region, known as the solid/liquid interface, moves from one end of the sample to the other at a controlled rate, thus the term directional solidification.

1983-01-01

321

Multiple hearth furnace for reducing iron oxide  

DOEpatents

A multiple moving hearth furnace (10) having a furnace housing (11) with at least two moving hearths (20) positioned laterally within the furnace housing, the hearths moving in opposite directions and each moving hearth (20) capable of being charged with at least one layer of iron oxide and carbon bearing material at one end, and being capable of discharging reduced material at the other end. A heat insulating partition (92) is positioned between adjacent moving hearths of at least portions of the conversion zones (13), and is capable of communicating gases between the atmospheres of the conversion zones of adjacent moving hearths. A drying/preheat zone (12), a conversion zone (13), and optionally a cooling zone (15) are sequentially positioned along each moving hearth (30) in the furnace housing (11).

Brandon, Mark M. (Charlotte, NC); True, Bradford G. (Charlotte, NC)

2012-03-13

322

Energy Assessment Protocol for Glass Furnaces  

E-print Network

The Department of Energy funded development of a methodology that could be used by glass producers to increase furnace efficiency, and that could serve as a model for other energy-intensive industries. Accordingly, a team comprising PPG Industries...

Plodinec, M. J.; Kauffman, B. M.; Norton, O. P.; Richards, C.; Connors, J.; Wishnick, D.

2005-01-01

323

Removable preheater elements improve oxide induction furnace  

NASA Technical Reports Server (NTRS)

Heat and corrosion resistant preheater elements are used in oxide induction furnaces to raise the temperature to the level for conducting electricity. These preheater elements are then removed and the induction coil energized.

Leipold, M. H.

1964-01-01

324

The high-quality, efficient, automated heat treatment of semi-processed electrical steel laminations in small batch quantities  

NASA Astrophysics Data System (ADS)

The paper highlights the advantages of using semi-processed electrical steel sheet and provides conclusive evidence that this material can be consistently and economically processed to the highest standards in a modern-design batch furnace. The paper also suggests the wide versatility of the furnace to process other grades and alternative heat treatment cycles.

Hancock, R. G.; Dolman, S. E.

1984-02-01

325

Developing composite furnace module cooling systems  

Microsoft Academic Search

The composite furnace module cooling system is designed to provide an essentially uniform hot-face temperature that is low\\u000a enough to promote the formation of a protective accretion layer for furnace containment. A minimal amount of copper is used\\u000a to ensure that the installation of the modules will not significantly alter the process heat balance during normal operation.\\u000a The modules have

A. K. Kyllo; N. B. Gray; D. Papazoglou; B. J. Elliot

2000-01-01

326

Universal energy-efficient refining furnace  

Microsoft Academic Search

This article examines new designs of fluidized-bed furnaces that make it possible to solve a number of engineering problems.\\u000a Descriptions are given of the furnaces and their possible applications: recycling of small pieces of scrap and chips without\\u000a their preliminary processing (briquetting and the removal of oil and grinding debris from their surface); the production of\\u000a a synthetic glass-ceramic material

G. S. Sborshchikov; S. A. Krupennikov

2009-01-01

327

Calcining petroleum coke in ring furnace  

Microsoft Academic Search

1.The process of calcining has been studied for total petroleum coke (size 0–60 mm) and breeze (0–15 mm) in an experimental ring furnace.2.It has been shown that the ring furnace can be used successfully to calcine any size grade of petroleum coke produced by delayed coking.3.The quality of the calcined coke, according to the tests of VAMI and GOSNIIÉP, satisfies

Yu. V. Bentsianov; V. E. Ivanov; G. N. Makarov; M. M. Akhmetov; S. M. Slutskaya; F. A. Mustafin

1974-01-01

328

Atom diffusion in furnaces — models and measurements  

NASA Astrophysics Data System (ADS)

Experimental as well as the theoretical approach to estimate diffusion coefficients for several analyte elements with different behavior in graphite furnaces, lead, gold, indium and chromium, were investigated. 'Close' graphite furnaces of two designs differing in the size of end apertures and the diameter of the injection port were used. The furnaces were fast heated at rates of approximately 10 000 K s -1. The peak absorbance of all studied analytes was independent of geometry, suggesting that the separation of atomization and removal was attained. Residence times of the analytes in the two different furnaces were determined from absorbance tail shapes. In the case of gold, the influence of temperature in the range between 1800 and 2200 K on the residence time in both furnaces was also found. The residence times measured in the two different furnaces under otherwise identical conditions, made possible to select the accurate model of diffusional removal from several possible models. The knowledge of the accurate model allowed the estimate of experimental diffusion coefficients. They were thus compared with those semiempirically calculated from kinetic theory of gases, extended to allow for the intermolecular forces. The accuracy of these calculations is limited since the input data (critical temperatures, boiling temperature or melting temperature, molal volumes at the critical, boiling and melting points, metallic crystallographic radii and dissociation constants of metal dimers) are not known with adequate accuracy. The comparison of 'theoretical' and 'experimental' values of diffusion coefficients makes possible to assess value of using individual sources of input data for the semiempirical calculations.

Sadagoff, Yu. M.; D?dina, J.

2002-03-01

329

Behavior of phosphorus in DRI/HBI during electric furnace steelmaking  

NASA Astrophysics Data System (ADS)

In modern electric arc furnace (EAF) steelmaking, ore based scrap substitute materials are often used to control the chemistry of the steel produced and/or improve the efficiency of the process. Metallographic investigation of commercial direct reduced iron/hot briquetted iron, DRI/HBI materials indicates that before melting, phosphorus in DRI/HBI is contained as a calcium phosphate phase in the unreduced oxide "gangue" portion of the material. It was assumed that the kinetics of phosphorus transfer between slag and metal are limited by liquid phase mass transfer of phosphorus in the slag, metal, or both phases. An overall mass transfer coefficient, ko, was defined, which includes the effects of mass transfer in both the slag and the metal. Fundamental laboratory kinetic experiments indicate that either the slag-metal interfacial area, A, and/or the overall liquid phase mass transfer coefficient, ko, change during dephosphorization experiments. Because the contributions of the reaction area and the mass transfer coefficient to the overall rate are difficult to separate, experimental results were analyzed in terms of the mass transfer parameter, A*ko. The liquid phase mass transfer parameter for dephosphorization was found to range between 10-7 to 1 x 10-3 cm3/s for different experimental conditions. Plant trials were conducted to directly evaluate the conditions of mass transfer in the electric furnace. Controlled mass transfer experiments were conducted on a 150 ton DC electric arc furnace. The mass transfer parameter, A*ko, for this furnace was determined to be between 1.7*104 and 3.5*105 cm3/s. An additional series of plant trials were conducted on a 150 ton AC electric furnace to examine the effects of different scrap substitute materials upon the slag chemistry, the behavior of phosphorus in the steel, and upon furnace yield. The data from these trials were also used to develop empirical models for the slag chemistry and furnace temperature as functions of time during a single heat. A numerical process model was used to evaluate the influence of various EAF operating parameters upon phosphorus mass transfer between the slag and metal. (Abstract shortened by UMI.)

Manning, Christopher Patrick

330

Study of Room Temperature and Humidity Control Method on Dehumidification System Reheated by Refrigeration Cycle  

NASA Astrophysics Data System (ADS)

The new ways to control the humidity and the temperature of the room accurately during the dehumidification operation reheated by refrigeration cycle on room air conditioners using R 410A was investigated. The indoor heat exchanger is divided into a condensing part and an evaporating part by a dehumidification valve which is located between these two heat exchangers. The indoor air cooled and dehumidified by the evaporating part is heated by the condensing part. The dehumidification capacity increased according to increasing the compressor rotational speed. And the reheating capacity increased according to decreasing the outdoor fan rotational speed. So the humidity and the temperature of the room was controlled to the setting values exactly by regulating the compressor rotational speed and the outdoor fan rotational speed alternately.

Nakamura, Hiroo; Funakoshi, Sunao; Yokoyama, Hidenori; Morimoto, Motoo; Saito, Kiyoshi

331

Simultaneous Measurements of Temperature and Iron-Slag Ratio at Taphole of Blast Furnace  

NASA Astrophysics Data System (ADS)

As the initial process in an integrated steel-making plant, molten iron is produced in a blast furnace. The molten iron has a temperature between 1700 K and 1900 K. The outflow stream discharged from a taphole comprises the molten iron and slag (which is a mixture of molten oxides). Monitoring of the stream temperature is important because it has information on the thermal condition inside the blast furnace. A newly developed simultaneous measurement technique for temperature and iron-slag ratio is reported. A monochromatic CCD camera with a short exposure time is used to obtain a thermal image of the rapidly moving stream. The thermal image has a marble-like pattern caused by the physical separation of the iron and slag and their different optical properties. Iron thermometry is realized by automatically detecting the peak of the iron gray-level distribution on a histogram. Meanwhile, the thermal radiance of the semitransparent slag varies as a function of the thickness. The slag temperature is calculated from the maximum gray level, presuming that the emissivity of the slag is constant at a thick slag part. The slag ratio is measured by counting the number of pixels on the histogram. A field test was carried out at an operating blast furnace. The iron temperature, slag temperature, and slag ratio were successfully measured. This multiple image measurement is expected to be the new information source for stable blast furnace operation.

Sugiura, M.; Shinotake, A.; Nakashima, M.; Omoto, N.

2014-07-01

332

Study of structure formation and reheating in the D3/D7 brane inflation model  

SciTech Connect

We study the spectrum of cosmological fluctuations in the D3/D7 brane inflationary universe with particular attention to the parametric excitation of entropy modes during the reheating stage. The same tachyonic instability which renders reheating in this model very rapidly leads to an exponential growth of entropy fluctuations during the preheating stage which in turn may induce a large contribution to the large-scale curvature fluctuations. We take into account the effects of long wavelength quantum fluctuations in the matter fields. As part of this work, we perform an analytical analysis of the reheating process. We find that the initial stage of preheating proceeds by the tachyonic instability channel. An upper bound on the time it takes for the energy initially stored in the inflaton field to convert into fluctuations is obtained by neglecting the local fluctuations produced during the period of tachyonic decay and analyzing the decay of the residual homogeneous field oscillations, which proceeds by parametric resonance. We show that, in spite of the fact that the resonance is of the narrow-band type, it is sufficiently efficient to rapidly convert most of the energy of the background fields into matter fluctuations.

Brandenberger, Robert H.; Dasgupta, Keshav [Department of Physics, McGill University, Montreal, QC, H3A 2T8 (Canada); Davis, Anne-Christine [DAMTP, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom)

2008-10-15

333

Composite Furnace Modules - Application in DC Furnaces for FeNi alloy production  

Microsoft Academic Search

The arduous operating conditions in high intensity furnaces require specialized equipment incorpo- rated into the containment vessel to ensure viable, long term operation. This is particularly true for high temperature pyrometallurgical processes where the slag constituents are chemically aggressive to the conventional refractory materials utilized in the sidewall lining. Smelting of nickeliferous lateritic ores in an electric furnace is an

Frik Marx; Mike Shapiro; Isabel Geldenhuys; Nico Fowler; Neil B. Gray

334

Formation of Nitrogen-Pearlite in the Diffusion Bonding of Sialon to 316L Stainless Steel  

Microsoft Academic Search

The objective of this study is to investigate the interface reaction and diffusion bonding between 316L stainless steel and sialon. Bonding was carried out in a hot press at 1250° C under the pressure of 15 MN\\/m2 for 1 hour and was cooled slowly in the furnace to prevent the mismatch between the sialon and the steel. Scanning Electron microscopy

P. Hussain; O. Mamat; M. Mohammad; W. M. N. W. Jaafar

2010-01-01

335

Speciation of Cr and V within BOF steel slag reused in road constructions  

Microsoft Academic Search

Basic Oxygen Furnace (BOF) steel slag is a residue from the basic oxygen converter in steel-making operations, which is partially reused as an aggregate for road constructions. It is essentially composed of calcium, silicon and iron but also contains potential toxic elements present as traces, like chromium (Cr, 2600 mg kg?1) and vanadium (V, 690 mg kg?1), which can be

Perrine Chaurand; Jérôme Rose; Jérémie Domas; Jean-Yves Bottero

2006-01-01

336

Environmental impacts of steel slag reused in road construction: A crystallographic and molecular (XANES) approach  

Microsoft Academic Search

Basic oxygen furnace (BOF) steel slag is a residue from the basic oxygen converter in steel-making operations, and is partially reused as an aggregate for road constructions. Although BOF slag is an attractive building material, its long-term behaviour and the associated environmental impacts must be taken into account. Indeed BOF slag is mainly composed of calcium, silicon and iron but

Perrine Chaurand; Jerome Rose; Valérie Briois; Luca Olivi; Jean-Louis Hazemann; Olivier Proux; Jérémie Domas; Jean-Yves Bottero

2007-01-01

337

Controlling the composition of nonmetallic inclusions in a low-alloy manganese steel  

Microsoft Academic Search

At the modern level of out-furnace treatment of steel, the steel composition becomes a substantial factor that determines the degree of influence of oxide particles on its properties. Therefore, the development of a method for controlling the inclusion composition is a challenging and technologically feasible problem. In this work, we study the possibility of controlling the composition of nonmetallic inclusions

A. V. Dub; A. N. Romashkin; Yu. V. Gordeev; G. G. Shvetsov; I. V. Zinkovskii

2009-01-01

338

Energy efficient operation of aluminum furnaces  

SciTech Connect

Secondary Aluminium melting offers significant energy savings over the production of Aluminium from raw resources since it takes approximately 5% of the energy to re-melt the Aluminium for product than it does to generate the same amount of Aluminium from raw material. However, the industry faces technical challenges for further improving the efficiency of the secondary Aluminium melting furnaces and lacks tools that can aid in helping to understand the intricate interactions of combustion and heat transfer. The U. S. Dept. of Energy, Albany Research Center (ARC), in cooperation with the Argonne and Oak Ridge National Labs, the University of Kentucky, and with industrial support through Secat, Inc. of Lexington, KY (representing 8 Aluminium re-melt companies) built and operates a test-bed reverberatory furnace to study efficiency issues in Aluminium melting. The experimental reverberatory furnace (ERF) is a one ton nominal capacity research furnace capable of melting 1000 lbs per hour with its twin 0.8 MMBtu/hr burners. Studies in the ERF include melt efficiency as a function of combustion space volume, power input and charge alloy. This paper details the experimental equipment, conditions, procedures, and measurements and includes results and discussions of melt efficiency studies. Specific results reported include an analysis of the efficiency of the furnace as a function of power input and the effect that changing combustion space volume has on melting efficiency. In conjunction with this, a computational fluid dynamics (CFD) model has been developed to simulate fuel combustion, heat transfer, gaseous product flow and the production/transport of pollutants and greenhouse gases in an Aluminium furnace. Data from the ERF is utilized for computational model validation in order to have a high degree of confidence in the model results. Once validated, the CFD code can then be used to perform parametric studies and to investigate methods to optimize operation in industrial furnaces. Finally, an analytic analysis of the efficiency of the furnace under varying conditions was conducted to determine overall efficiency characteristics of the furnace.

King, Paul E.; Golchert, B.M. (ANL); Li, T. (University of Kentucky); Hassan, M. (University of Kentucky); Han, Q. (ORNL)

2005-01-01

339

Effect of electric arc furnace slag on growth and physiology of maize (Zea mays L.).  

PubMed

Basic slag, used in this study as a potential source of certain nutrients, is a byproduct of the production of steel in electric arc furnace (EAF). A pot experiment with two nutrient-poor substrates was conducted to investigate to compare the effect of EAF steel slag and fertilizers NPK + F e on growth and availability of specific nutrients to maize. Mineral content of both substrate and plant leaves, growth, chlorophyll fluorescence and photosynthetic pigments were measured following six weeks of cultivation. As steel slag also contains trace amounts of heavy metals, certain oxidative parameters (antioxidative enzyme activities and lipid peroxidation) were evaluated as well. The steel slag improved soil mineral composition, increased above ground maize biomass by providing Fe, Mn, Mg, K and partly P and improved photosynthetic parameters. The potential phytotoxicity of EAF slag containing substrates was not determined as evaluated by MDA (malondialdehyde), GR (glutathione reductase) and APX (ascorbate peroxidase) levels. The obtained results show that EAF steel slag is comparable to NPK + F e in supplying nutrients for maize growth, indicating the potential of EAF steel slag as an inexpensive and non-phytotoxic nutrient supplier especially in poor soils. PMID:24275594

Radi?, Sandra; Crnojevi?, Helena; Sandev, Dubravka; Jeli?, Sonja; Sedlar, Zorana; Glavaš, Katarina; Pevalek-Kozlina, Branka

2013-12-01

340

Induction furnace testing of the durability of prototype crucibles in a molten metal environment  

SciTech Connect

Engineered ceramic crucibles are commonly used to contain molten metal. Besides high temperature stability, other desired crucible characteristics include thermal shock resistance, minimal reaction with the molten metal and resistance to attack from the base metal oxide formed during melting. When used in an induction furnace, they can be employed as a “semi-permanent” crucible incorporating a dry ram backup and a ceramic cap. This report covers several 250-lb single melt crucible tests in an air melt induction furnace. These tests consisted of melting a charge of 17-4PH stainless steel, holding the charge molten for two hours before pouring off the heat and then subsequently sectioning the crucible to review the extent of erosion, penetration and other physical characteristics. Selected temperature readings were made throughout each melt. Chemistry samples were also taken from each heat periodically throughout the hold. The manganese level was observed to affect the rate of chromium loss in a non-linear fashion.

Jablonski, Paul D.

2005-09-01

341

Saldanha Steel project: The zero emission philosophy  

SciTech Connect

Saldanha Steel is a new, green-field, semi-integrated steelworks developed on the west coast near the southern tip of Africa. The harbor in Saldanha Bay was developed as an iron ore export facility for Sishen ore in the late seventies. The Sishen Iron Ore Mine is located some 800 km inland and is currently exporting about 17 million tons annually. Saldanha steel will now utilize some 2 million tons per annum of this ore, of which about 45% will be converted into liquid iron in a Corex direct reduction smelting process. Excess reducing gas (CO and H{sub 2}) from the Corex plant will then be used to convert the remaining 55% of the iron ore into solid sponge iron (DRI) via a Midrex plant. The liquid and solid iron will be further processed in a Conarc furnace, which is a hybrid between an oxygen converter and an electric arc furnace.

Holmes, A.T. [Saldanha Steel, Rivonia (South Africa); Greenwalt, D. [Bechtel, San Francisco, CA (United States)

1997-12-31

342

Softened-Stainless-Steel O-Rings  

NASA Technical Reports Server (NTRS)

In fabrication of O-ring of new type, tube of 304 stainless steel bent around mandril into circle and welded closed into ring. Ring annealed in furnace to make it soft and highly ductile. In this condition, used as crushable, deformable O-ring seal. O-ring replacements used in variety of atmospheres and temperatures, relatively inexpensive, fabricated with minimum amount of work, amenable to one-of-a-kind production, reusable, and environmentally benign.

Marquis, G. A.; Waters, William I.

1993-01-01

343

Steamside Oxidation Behavior of Experimental 9%Cr Steels  

SciTech Connect

Reducing emissions and increasing economic competitiveness require more efficient steam power plants that utilize fossil fuels. One of the major challenges in designing these plants is the availability of materials that can stand the supercritical and ultra-supercritical steam conditions at a competitive cost. There are several programs around the world developing new ferritic and austenitic steels for superheater and reheater tubes exposed to the advanced steam conditions. The new steels must possess properties better than current steels in terms of creep strength, steamside oxidation resistance, fireside corrosion resistance, and thermal fatigue resistance. This paper introduces a series of experimental 9%Cr steels containing Cu, Co, and Ti. Stability of the phases in the new steels is discussed and compared to the phases in the commercially available materials. The steels were tested under both the dry and moist conditions at 650ºC for their cyclical oxidation resistance. Results of oxidation tests are presented. Under the moist conditions, the experimental steels exhibited significantly less mass gain compared to the commercial P91 steel. Microstructural characterization of the scale revealed different oxide compositions.

Dogan, O.N.; Holcomb, G.R.; Alman, D.E.; Jablonski, P.D.

2007-10-01

344

Improved Heat Treatment Of Steel Alloy 4340  

NASA Technical Reports Server (NTRS)

New process takes significantly less time than prior heat-treatment processes. Involves placing steel plate directly in furnace and heat-treating. Plate then quenched in slowly moving oil to reduce stresses. Any deflection then pressed out. Possible uses of 4340 steel include new and improved bulletproof vests for military and police personnel and armor for bulletproof automobiles for military, police, diplomatic, and private users. Also used in other military land vehicles as tanks and in both military and civilian aircraft. Lighter armorplate enables land vehicles and aircraft to attain greater speed and maneuverability, consume less fuel, and afford better protection from snipers or terrorists.

Cooper, Lawrence B.

1993-01-01

345

Acoustic Levitator With Furnace And Laser Heating  

NASA Technical Reports Server (NTRS)

Acoustic-levitation apparatus incorporates electrical-resistance furnace for uniform heating up to temperature of about 1,000 degrees C. Additional local heating by pair of laser beams raise temperature of sample to more than 1,500 degrees C. High temperature single-mode acoustic levitator generates cylindrical-mode accoustic resonance levitating sample. Levitation chamber enclosed in electrical-resistance furnace. Infrared beams from Nd:YAG laser provide additional local heating of sample. Designed for use in containerless processing of materials in microgravity or in normal Earth gravity.

Barmatz, Martin B.; Stoneburner, James D.

1991-01-01

346

High temperature furnace modeling and performance verifications  

NASA Technical Reports Server (NTRS)

A two dimensional conduction/radiation problem for an alumina crucible in a zirconia heater/muffle tube enclosing a liquid iron sample was solved numerically. Variations in the crucible wall thickness were numerically examined. The results showed that the temperature profiles within the liquid iron sample were significantly affected by the crucible wall thicknesses. New zirconia heating elements are under development that will permit continued experimental investigations of the zirconia furnace. These elements have been designed to work with the existing furnace and have been shown to have longer lifetimes than commercially available zirconia heating elements. The first element has been constructed and tested successfully.

Smith, James E., Jr.

1991-01-01

347

TiC reinforced cast chromium steels  

SciTech Connect

A series of new titanium carbide reinforced cast chromium steels were developed for wear applications. Objective of the program was to enhance wear resistant alloys and, if possible, improve mechanical properties. The new steels which were melted in a vacuum induction furnace contained 12 Cr, 3-5 Ti, 1-2 C in weight percent. Alloying with Ti changed the precipitate microstructure from Cr carbide to TiC dispersed in a martensitic matrix. Yield strength and impact resistance improved with Ti alloying. Wear rates of the cast Cr/TiC steels, (determined from high- and low-stress abrasion tests, erosion test, and scratch tests) were generally lower than both the as-cast and heat-treated AISI type 440°C steel and were often further reduced by increasing the Ti alloy concentration. The exceptions were the erosion test for which all materials had similar wear rate.

Dogan, Omer N.; Rawers, James C.; Hawk, Jeffrey A.; Schrems, Karol K.

2003-11-01

348

TiC reinforced cast Cr steels  

SciTech Connect

A new class of materials, namely TiC-reinforced cast chromium (Cr) steels, was developed for applications requiring high abrasion resistance and good fracture toughness. The research approach was to modify the carbide structure of commercial AISI 440C steel for better fracture resistance while maintaining the already high abrasion resistance. The new alloys contained 12Cr, 2.5–4.5Ti, and 1–1.5C (wt.%) and were melted in a vacuum induction furnace. Their microstructure was composed primarily of a martensitic matrix with a dispersion of TiC precipitates. Modification of TiC morphology was accomplished through changing the cooling rate during solidification. Wear rates of the TiC-reinforced Cr steels were comparable to that of AISI 440C steel, but the impact resistance was much improved.

Dogan, O.N.; Hawk, J.A.; Schrems, K.K.

2006-06-01

349

UNIVERSITY OF WASHINGTON ELECTROSTATIC SCRUBBER TESTS AT A STEEL PLANT  

EPA Science Inventory

The report gives results of a demonstration of the effectiveness of a 1700 cu m/hr (1000 acfm) University of Washington (UW) Electrostatic Spray Scrubber in controlling fine particle emissions from an electric-arc steel furnace. The two-stage portable pilot plant operates by comb...

350

Coal combustion under conditions of blast furnace injection. [Quarterly] technical report, 1 March 1993--31 May 1993  

SciTech Connect

A potentially new use for Illinois coal is its use as a fuel injected into a blast furnace to produce molten iron as the first step in steel production. Because of its increasing cost and decreasing availability, metallurgical coke is now being replaced by coal injected at the tuyere area of the furnace where the blast air enters. The purpose of this study is to evaluate the combustion of coal during the blast furnace injection process and to delineate the optimum properties of the feed coal. The basic program is designed to determine the reactivity of both coal and its derived char under blast furnace conditions and to compare the results to similar properties of blast furnace coke. The results of the first two experiments in which coal char pyrolyzed in nitrogen at 1000{degrees}C in an EPR were reacted isothermally in air at 1000{degrees}C and 1200{degrees}C. The reactivity values of the same char in these two experiments were different by an order of magnitude. The char reactivity at 1000{degrees}C was 9.7 {times} 10{sup {minus}4} grams per minute while the reactivity. of the char at 1200{degrees}C was 1.6 {times} 10{sup {minus}3} grams per minute. These results suggest that the temperature of the blast air in the tuyere may be critical in achieving complete carbon burnout.

Crelling, J.C. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Geology; Case, E.R. [Armco, Inc., Middletown, OH (United States). Research and Technology Div.

1993-09-01

351

Analysis and prevention of cracking phenomenon occurring during cold forging of two AISI 1010 steel pulleys  

Microsoft Academic Search

This study is concerned with the effects of microstructural parameters on the cracking phenomenon occurring during cold forging\\u000a of two AISI 1010 steels that were fabricated by converter steel making and electric furnace steel making, respectively. This\\u000a allowed a comparison between microstructures that contained a small or large amount of nitrogen. Detailed microstructural\\u000a analyses of the cracked region showed that

Dong-Kuk Kim; Suk Young Kang; Sunghak Lee; Kyung Jong Lee

1999-01-01

352

46 CFR 164.009-11 - Furnace apparatus.  

Code of Federal Regulations, 2010 CFR

...voltage stabilizer, specimen holder, specimen insertion device, and three thermocouples (a furnace thermocouple to measure furnace temperature, a surface thermocouple to measure temperature at the surface of a specimen, and a specimen...

2010-10-01

353

33. BOILER HOUSE FURNACE AND BOILER Close view of ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

33. BOILER HOUSE - FURNACE AND BOILER Close view of the Dorward Engineering Company furnace and boiler which provided steam to the cooking retorts in the adjacent room. - Hovden Cannery, 886 Cannery Row, Monterey, Monterey County, CA

354

36. REDUCTION PLANT CLOSE VIEW OF FURNACE AND BOILER ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

36. REDUCTION PLANT - CLOSE VIEW OF FURNACE AND BOILER Reduction Plant furnace and boiler used to provide heat for drying the fish and fish offal, in their conversion to meal. - Hovden Cannery, 886 Cannery Row, Monterey, Monterey County, CA

355

6. Photocopy of a drawing of the lead blast furnace ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. Photocopy of a drawing of the lead blast furnace from J.L. Bray, The Principles of Metallurgy, Ginn & Co. New York, 1929. - International Smelting & Refining Company, Tooele Smelter, Blast Furnace Building, State Route 178, Tooele, Tooele County, UT

356

ENVIRONMENTAL ASSESSMENT OF STEELMAKING FURNACE DUST DISPOSAL METHODS  

EPA Science Inventory

The report gives results of a study to examine the nature of steelmaking furnace residues and disposal techniques, and to assess potential problems associated with residue disposal, a potential multimedia environmental problem. Solubilization tests of 18 furnace residue samples s...

357

CHEMICAL ANALYSIS OF PARTICLE SIZE FRACTIONS FROM GLASS MELTING FURNACES  

EPA Science Inventory

The purpose of this research was to identify the size fraction distribution of the various chemical constituents of glass furnace emissions. This would assist researchers in identifying emissions characteristic of glass furnaces; thus, providing design requirements for control te...

358

Design and fabrication of a tin-sulfide annealing furnace  

E-print Network

A furnace was designed and its heat transfer properties were analyzed for use in annealing thin-film tins-ulfide solar cells. Tin sulfide has been explored as an earth abundant solar cell material, and the furnace was ...

Lewis, Raymond (Raymond A.)

2011-01-01

359

A recycling process for dezincing steel scrap  

SciTech Connect

In response to the several-fold increase in consumption of galvanized steel in the last decade and the problems associated with refurnacing larger quantities of galvanized steel scrap, a process is being developed to separate and recover the steel and zinc from galvanized ferrous scrap. The zinc is dissolved from the scrap in hot caustic using anodic assistance and is electrowon as dendritic powder. The process is effective for zinc, lead, aluminum, and cadmium removal on loose and baled scrap and on all types of galvanized steel. The process has been pilot tested for batch treatment of 1,000 tons of mostly baled scrap. A pilot plant to continuously treat loose scrap is under construction. Use of degalvanized steel scrap decreases raw materials and environmental compliance costs to steel- and iron-makers, may enable integrated steel producers to recycle furnace dusts to the sinter plant, and may enable EAF production of flat products without use of DRI or pig iron. Recycling the components of galvanized steel scrap saves primary energy, decreases zinc imports, and adds value to the scrap.

Dudek, F.J.; Daniels, E.J. (Argonne National Lab., IL (United States)); Morgan, W.A.; Kellner, A.W.; Harrison, J. (Metal Recovery Industries, Inc., Hamilton, ON (Canada))

1992-01-01

360

A recycling process for dezincing steel scrap  

SciTech Connect

In response to the several-fold increase in consumption of galvanized steel in the last decade and the problems associated with refurnacing larger quantities of galvanized steel scrap, a process is being developed to separate and recover the steel and zinc from galvanized ferrous scrap. The zinc is dissolved from the scrap in hot caustic using anodic assistance and is electrowon as dendritic powder. The process is effective for zinc, lead, aluminum, and cadmium removal on loose and baled scrap and on all types of galvanized steel. The process has been pilot tested for batch treatment of 1,000 tons of mostly baled scrap. A pilot plant to continuously treat loose scrap is under construction. Use of degalvanized steel scrap decreases raw materials and environmental compliance costs to steel- and iron-makers, may enable integrated steel producers to recycle furnace dusts to the sinter plant, and may enable EAF production of flat products without use of DRI or pig iron. Recycling the components of galvanized steel scrap saves primary energy, decreases zinc imports, and adds value to the scrap.

Dudek, F.J.; Daniels, E.J. [Argonne National Lab., IL (United States); Morgan, W.A.; Kellner, A.W.; Harrison, J. [Metal Recovery Industries, Inc., Hamilton, ON (Canada)

1992-08-01

361

Innovative Energy Conservation Through Scrao Pre-heating in an Electric Arc Furnace  

E-print Network

incentives, the facility was able to upgrade their electric arc furnace (EAF). In order to acquire the incentive, the facility was required to submit an application and information to support the savings and costs of the project which were required... to provide measurement and verification (M&V) data to demonstrate the measure?s electricity savings for 10 years after the measure is declared to be in service. Prior to the upgrade, the EAF at Ivaco Rolling Mills 2004 L.P. melted recycled steel scrap...

Dicion, A.

2013-01-01

362

46 CFR 59.15-1 - Furnace repairs.  

Code of Federal Regulations, 2012 CFR

...of the furnace and the diameter of a true circle at the same location. The diameter of the true circle may be taken as the original furnace diameter...necessary to force the furnace back to a true circle if the allowable pressure is reduced in...

2012-10-01

363

46 CFR 59.15-1 - Furnace repairs.  

Code of Federal Regulations, 2010 CFR

...of the furnace and the diameter of a true circle at the same location. The diameter of the true circle may be taken as the original furnace diameter...necessary to force the furnace back to a true circle if the allowable pressure is reduced in...

2010-10-01

364

46 CFR 59.15-1 - Furnace repairs.  

Code of Federal Regulations, 2011 CFR

...of the furnace and the diameter of a true circle at the same location. The diameter of the true circle may be taken as the original furnace diameter...necessary to force the furnace back to a true circle if the allowable pressure is reduced in...

2011-10-01

365

46 CFR 59.15-1 - Furnace repairs.  

Code of Federal Regulations, 2013 CFR

...of the furnace and the diameter of a true circle at the same location. The diameter of the true circle may be taken as the original furnace diameter...necessary to force the furnace back to a true circle if the allowable pressure is reduced in...

2013-10-01

366

Power Usage and Electrical Circuit Analysis for Electric Arc Furnaces  

Microsoft Academic Search

Power usage in ultrahigh-powered electric arc furnaces requires considerably more investigation into system parameters, furnace secondary circuit analysis, and operating characteristics than previously given to normal powered electric arc furnaces. The power input must be analyzed from the infinite electric utility bus to the arc at the electrode. All interested parties must participate in the analysis to assure a mutual

J. J. Trageser

1980-01-01

367

ANALYSIS OF EMISSIONS FROM RESIDENTIAL NATURAL GAS FURNACES  

EPA Science Inventory

The paper gives emissions data from residential natural-gas furnaces and compares selected data to emissions data from residential oil furnaces and woodstoves. atural-gas furnace emissions data are given for carbon monoxide (CO), unburned hydrocarbons, aldehydes, volatile and sem...

368

29. Blast furnace plant, looking southeast. The Machine Shop and ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

29. Blast furnace plant, looking southeast. The Machine Shop and Turbo Blower Building are at left, the pig-casting machine and Furnace A at center right. In foregound are the 50-ton ladle cars used to transport hot metal to Valley Mould & Iron Co. - Central Furnaces, 2650 Broadway, east bank of Cuyahoga River, Cleveland, Cuyahoga County, OH

369

8. Copy of a photograph taken c. 1912 of Furnace ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. Copy of a photograph taken c. 1912 of Furnace 'D' blown-in 17 July 1911, the fourth experimental 'thin-lined furnace' to be built in the United States. Photo courtesy Ralph A. Dise, Cleveland Heights, Ohio. - Central Furnaces, 2650 Broadway, east bank of Cuyahoga River, Cleveland, Cuyahoga County, OH

370

Comment on `Recombination induced softening and reheating of the cosmic plasma'  

E-print Network

Leung, Chan & Chu (2004) claimed that a previously neglected reheating effect makes a small but noticeable change to the process of cosmological recombination. We revisit this effect by considering a system consisting of both radiation and ionizing gas under adiabatic expansion. In the thermal equilibrium limit, due to the huge radiation background, only a fraction about 10^-10 of the heat released from the recombination of atoms is shared by the matter. And in the standard hydrogen recombination calculation, the maximum fraction of energy lost by the distortion photons through multiple Compton scattering is certainly less than 10^-3. Thus this effect is negligible.

Wan Yan Wong; Douglas Scott

2006-12-12

371

Electrode mounting in DC arc furnace vessels  

Microsoft Academic Search

A vessel is described for a dc arc furnace having a bottom with a refractory lining, there being a cooled electric current feeding structure arranged outside of the vessel underneath the bottom, and further including a plurality of electrode pins, the improvement comprising a separate mounting facility for each pin, including in each instance: a bore in the lining; an

1986-01-01

372

Glassification of electric arc furnace dust  

Microsoft Academic Search

The Glassification process is a unique system that treats hazardous materials such as electric arc furnace dust, slag, spent refractories, etc, and produces an inert, nontoxic marketable commodity. A wide variety of end products include: colored glasses; glass-ceramics that resemble natural rocks used for architectural purposes and decorative articles; roofing granules; abrasive grit; brick and tile colorants; and fillers. This

R. B. Ek; J. E. Schlobohm

1993-01-01

373

Thermal model of the whole element furnace  

SciTech Connect

A detailed thermal analysis was performed to calculate temperatures in the whole element test furnace that is used to conduct drying studies of N-Reactor fuel. The purpose of this analysis was to establish the thermal characteristics of the test system and to provide a basis for post-test analysis.

Cramer, E.R.

1998-01-22

374

Data acquisition from a crystal growth furnace  

NASA Technical Reports Server (NTRS)

Digital acquisition from a furnace for growing the lead tin telluride crystal based on Asyst software is described. It is shown that the use of Asyst for the acquisition of experimental data makes it possible to handle large amounts of data and to drastically reduce the time required for displaying the data from several hours to less than 5 minutes.

Woodell, Glenn A.

1988-01-01

375

High-gradient continuous-casting furnace  

NASA Technical Reports Server (NTRS)

High gradient allows rapid growth rates in directionally-solidified eutectic alloys. Furnace design permits cost reductions in directional solidification process through its increased solidification rates, which reduces melt/mold interaction. It produces structural engineering materials for any application requiring properties directionally-solidified eutectic materials.

Scheuermann, C. M.; Flemings, M. C.; Neff, M. A.; Rickinson, B. A.; Young, K. P.

1979-01-01

376

Protecting brazing furnaces from air leaks  

NASA Technical Reports Server (NTRS)

Inexpensive inert-atmosphere shielding protects vacuum brazing-furnace components that are likely to spring leak. Pipefittings, gages, and valves are encased in transparent plastic shroud inflated with argon. If leak develops, harmless argon will enter vacuum chamber, making it possible to finish ongoing brazing or heat treatment before shutting down for repair.

Armenoff, C. T.; Mckown, R. D.

1980-01-01

377

Concentration of a Cassegrain solar furnace  

Microsoft Academic Search

A solar furnace comprising a paraboloidal mirror for tracking the sun and a hyperboloidal reflector having one focus in common with the paraboloid is analyzed to determine the geometric concentration of the system. A numerical ray-trace analysis was carried out to study various geometrical configurations of the two reflectors. In particular, the geometric concentration is calculated for the case when

M. H. Cobble

1981-01-01

378

Estimation of parameters for a solar furnace  

SciTech Connect

An improved technique has been proposed based on Carlson's et al. modeling that can be used to estimate the reflectivity of the heliostat-concentrator system, the tracking errors and mirror imperfections in a lumped parameter for simulating the performance of a solar furnace as measured by a calorimeter.

Jarosch, H.S. (Weizmann Institute of Science, Rehovot (Israel))

1989-01-01

379

Intensifying the heat work of glass furnaces  

Microsoft Academic Search

cycles for the combustion of the fuel. Investigation of the process of heat transfer in the tank was limited to studying the transfer of heat as the result of natural convection from the hot zones to the zones which were heated to a lesser degree. Further intensification of the work of the glass tank furnaces by increasing the temperature in

L. S. Pioro; V. I. Babich

1966-01-01

380

APPLICATIONS ANALYSIS REPORT: RETECH PLASMA CENTRIFUGAL FURNACE  

EPA Science Inventory

This document is an evaluation of the performance of the Retech Inc. Plasma Centrifugal Furnace (PCF) and its applicability as a treatment technique for soils contaminated with organic and/or inorganic compounds. oth the technical and economic aspects of the technology were exami...

381

APPLICATION ANALYSIS REPORT: RETECH PLASMA CENTRIFUGAL FURNACE  

EPA Science Inventory

This document is an evaluation of the performance of the Retech, Inc. Plasma Centrifugal Furnace (PCF) and its applicability as a treatment for soils contaminated with organic and/or inorganic compounds. Both the technical and economic aspectsof the technology were examined. A...

382

Wear of Cast Chromium Steels With TiC Reinforcement  

SciTech Connect

Wear resistance of a series of new titanium carbide reinforced cast chromium steels was investigated under various wear conditions. The steels which were melted in a vacuum induction furnace contained 12 Cr, 3-5 Ti, 1-2 C in weight percent. Microstructure of these materials was characterized using scanning electron microscopy, light optical microscopy, and X-ray diffraction. Microstructure of steels consisted of TiC phase dispersed in a martensitic matrix. High-stress and low-stress abrasion tests, and an erosion test, were utilized to understand the wear behavior of these materials under different environments. The steels were tested in as-cast and heat treated conditions. Wear rates of the cast Cr/TiC steels were compared to those of an AISI type 440C steel and P/M composites reinforced with TiC.

Dogan,O.N.; Hawk, J.A.; Tylczak, J.H.

2001-10-01

383

[Measurement of chemical agents in metallurgy field: electric steel plant].  

PubMed

The steel industry maintains its important position in the context of the Italian production involving thousands of workers. The iron and steel processes are divided into primary steel industry, production of intermediate minerals, and secondary steel, scrap from the production of semi-finished industrial and consumer sector (metal inserted into components and metal used for dissipative uses, primarily coatings) and industrial waste. The paper presents the results of environmental monitoring carried out in some electric steel plant for the measurement of airborne chemicals that characterize the occupational exposure of workers employed in particular area like electric oven, to treatment outside the furnace, continuous casting area. For the sampling of the pollutants were used both personal and in fixed positions samplers. The pollutants measured are those typical of steel processes inhalable dust, metals, respirable dust, crystalline silica, but also Polycyclic Aromatic Hydrocarbons (PAH), polychlorinated dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). PMID:23213795

Cottica, D; Grignani, E; Ghitti, R; Festa, D; Apostoli, P

2012-01-01

384

Simulation of Frozen Slag Inside Brickless Reaction Shaft of Flash Smelting Furnace  

NASA Astrophysics Data System (ADS)

Based on the principle of heat transfer, a three-dimensional model of frozen slag in the brickless reaction shaft of a flash smelting furnace was established by computing the temperature field and judging the moving boundary. In the modeling process, a cylindrical coordinate system was adopted to specify the point positions according to the geometry of the brickless reaction shaft, and an improved method was proposed to discretize the three-dimensional control equations. The model was then applied to investigate the influence of the operational [gas temperature (GT), cooling water temperature (CWT), and melting temperature of frozen slag (MTFS)] and structural (steel shell thickness, steel nail thickness, steel nail length, and distance between nails) parameters on the thickness of the frozen slag. The results showed that the GT, CWT, and MTFS have a marked impact on the thickness of frozen slag, which decreases at high temperature and increases when cooled; the structural parameters have little effect on the thickness of frozen slag in terms of heat transfer. Consequently, to form a layer of frozen slag with a desired thickness inside a brickless reaction shaft, it is important to avoid localized ultra-high temperatures in the inner chamber and to cool the steel shell using a strong flow of low-temperature water; mechanical (and not thermal) factors should take precedence when designing the steel nails of a brickless reaction shaft.

Wang, Jinliang; Wang, Houqing; Tong, Changren; Zhang, Wenhai; Zhang, Chuanfu

2013-12-01

385

6. Photocopied August 1978. LINEUP OF HORRY ROTARY FURNACES ON ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. Photocopied August 1978. LINE-UP OF HORRY ROTARY FURNACES ON THE SECOND FLOOR OF THE MICHIGAN LAKE SUPERIOR POWER COMPANY POWER HOUSE. THE HOPPERS WHICH FED THE RAW MATERIALS INTO THE FURNACES ARE SHOWN ABOVE THE FURNACES. AS THE 'SPOOL' OF THE FURNACE ROTATED PAST THE ELECTRODES PLATES WERE ADDED TO HOLD THE FINISHED PRODUCT AND THE DESCENDING RAW MATERIALS IN PLACE. THE DIRECTION OF ROTATION OF THE FURNACES SHOWN IN THIS PHOTO IS CLOCKWISE, (M). - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

386

Analysis of a repowering proposal to the power generation system of a steel mill plant through the exergetic cost method  

Microsoft Academic Search

The rational use of energy became a priority for all industries in Brazil after the energetic rationing in 2001. The aim of this work is to assess a proposal of a power generation system for Companhia Siderúrgica Tubarão, a steel mill plant. The current system is based on a regenerative Rankine cycle using two gases from steel production—blast furnace gas

M. Modesto; S. A. Nebra

2006-01-01

387

Replacement of seam welded hot reheat pipe using narrow groove GTA machine welding  

SciTech Connect

Southern California Edison, recognizing a potential safety concern, scrutinized its existing seam welded hot reheat pipe manufactured by the same supplier as that which failed. Alternatives were narrowed to two in dealing with the installed seam welded pipe. The overriding consideration, however, was one of safety. With this in mind, the utility company evaluated replacement of the seam welded hot reheat pipe with seamless pipe or increasing the frequency of its inspection program. Although increased inspection was much costly, pipe replacement was chosen due to potential safety concerns with seam welded pipe even with more frequent inspection. The utility company then proceeded to determine the most effective method to complete this work. Analysis showed machine-made (automatic) gas tungsten arc welds (GTAW) as the method of choice due to cleanliness and superior mechanical properties. In conjunction with this method, the narrow groove (3{degree} bevel) weld joint as opposed to the traditional groove (37 1/2{degree} bevel) was shown to provide significant technical advantages.

Richardson, R.R.; Yanes, J.; Bryant, R.; Fennig, J.D.

1995-12-31

388

Effect of Reheat Treatment on Microstructural Refurbishment and Hardness of the As-cast Inconel 738  

NASA Astrophysics Data System (ADS)

This work investigates the effect of rejuvenation heat treatment conditions for refurbishment of the long-term serviced gas turbine blades, which were made of as-cast nickel base superalloy grade, Inconel 738. The reheat treatment conditions consist of solutionizing treatments at temperatures of 1,438, 1,458 and 1,478 K for 14.4 ks and aging treatments at temperatures of 1,133, 1,148 and 1,163 K for 43.2, 86.4, 129.6 and 172.8 ks. The results show that increase in aging times results in continuous increase of size and area fraction of gamma prime (?') particles. The higher solutionizing temperature leads to the lower area fraction and smaller size of gamma prime particles. Regarding the microstructure characteristics, the most proper reheat treatment condition should be solutionizing at temperature of 1,438 K for 14.4 ks and aging at temperature of 1,133 K for 172.8 ks, which provides the highest area fraction of gamma prime particles in proper size.

Wongbunyakul, Piyanut; Visuttipitukkul, Patama; Wangyao, Panyawat; Lothongkum, Gobboon; Sricharoenchai, Prasonk

2014-09-01

389

Multisystem corrosion monitoring in a cyclic reheat test facility: Phase 1  

SciTech Connect

The work described in this report was the first stage of an EPRI-sponsored corrosion investigation utilizing the CAPCIS electrochemical monitoring system installed in a cyclic reheat test facility on a flue gas slipstream at the Scholz Steam Plant of Gulf Power Company. The primary reasons for incorporating the continuous corrosion monitoring system in the cyclic reheat investigation were that unexpectedly high corrosion rates had been observed in earlier tests at certain locations within the test exchanger and the precise reasons for these high rates of attack were not well understood. The corrosion behavior was not typical of the limited service experience on full scale units and the reasons for this required clarification. Controlled temperature weight loss and electrochemical probes were installed in the unit in place of three of the 1-inch diameter heat exchanger tubes. The corrosion behavior of Inconel Alloy 625 over the temperature range 260/degree/ to 120/degree/F (127/degree/ to 49/degree/C) was evaluated at mid-stream and sidewall locations. The efects on corrosion of operational variables and cleaning procedures were also evaluated. The severe corrosion attack sustained on the Inconel Alloy 625 was proved to result from a combination of effects which included the flue gas flow pattern, local cool-spots within the unit and preferential locations at which ash deposits could accumulate. 5 refs., 50 figs., 17 tabs.

Farrell, D.M.; Cox, W.M.; Gearey, D.

1988-04-01

390

Wavelength dependence of prepulse laser beams on EUV emission from CO2 reheated Sn plasma  

NASA Astrophysics Data System (ADS)

Extreme ultraviolet (EUV) emission from laser-produced plasmas (LPP) centered at 13.5 nm is considered a leading candidate for the light source in future lithography systems. Tin is currently the best material for generating this EUV emission since it emits strongly within the 13.5 nm region due to its various ionic states (Sn8+-Sn14+). Highly efficient and low-debris LPPs are a pre-requisite for their use as light sources for EUV lithography. Tin plasmas generate debris that can damage collection optics over time. Techniques to mitigate debris are needed to extend the lifetime of these components and the system. Optimization of plasma conditions is necessary for increasing EUV emission and enhancing conversion efficiency (CE). Improving the source CE is necessary in order to reduce the cost of ownership and hence, develop a commercially viable lithography system for the semiconductor industry. One method to accomplish this is to reheat pre-formed plasma with a laser pulse to enhance EUV emission. This enhancement is achieved by controlling those plasma conditions necessary for optimizing EUV emission. We investigated the role of prepulse laser wavelength on prepulse plume formation and EUV in-band signal enhancement. A 6 ns Nd:YAG laser operating at 1064 nm and 266 nm was used for generating the prepulse plume. The expanding plume was then reheated by a 35 ns CO2 laser operating at 10.6 ?m. The role of prepulse wavelength and energy on EUV conversion efficiency is discussed.

Freeman, J. R.; Harilal, S. S.; Sizyuk, T.; Hassanein, A.; Rice, B.

2012-03-01

391

Production and blast-furnace smelting of boron-alloyed iron-ore pellets  

SciTech Connect

Industrial test data are presented regarding the production (at Sokolovsk-Sarbaisk mining and enrichment enterprise) and blast-furnace smelting (at Magnitogorsk metallurgical works) of boron-alloyed iron-ore pellets (500000 t). It is shown that, thanks to the presence of boron, the compressive strength of the roasted pellets is increased by 18.5%, while the strength in reduction is doubled; the limestone consumption is reduced by 11%, the bentonite consumption is halved, and the dust content of the gases in the last section of the roasting machines is reduced by 20%. In blast-furnace smelting, the yield of low-sulfur (<0.02%) hot metal is increased from 65-70 to 85.1% and the furnace productivity from 2.17-2.20 to 2.27 t/(m{sup 3} day); coke consumption is reduced by 3-8 kg/t of hot metal. The plasticity and stamping properties of 08IO auto-industry steel are improved by microadditions of boron.

A.A. Akberdin; A.S. Kim [Abishev Chemicometallurgical Institute, Abishev (Kazakhstan)

2008-08-15

392

Understanding environmental leachability of electric arc furnace dust  

SciTech Connect

Dust from production of steel in an electric arc furnace (EAF) contains a mixture of elements that pose a challenge for both recovery and disposal. This paper relates the leachability of six Canadian EAF dusts in four leaching tests [distilled water, Ontario Regulation 347 Leachate Extraction Procedure, Amount Available for Leaching (AALT), and pH 5 Stat] to their mineralogy. Chromium and nickel contaminants in EAF dust are largely unleachable (<5% available in AALT and pH 5 Stat), as they are found with the predominant spinel ferrite phase in EAF dust. However, even a small proportion of oxidized chromium can result in significant leachate concentrations of highly toxic chromate. The leachability of zinc (7--50% available), lead (2--17% available), and cadmium (9--55% available) can be significant, as large fractions of these contaminants are found as chlorides and oxides. The leaching of these metals is largely controlled by pH. The acid neutralization capacity of the EAF dusts appeared to be controlled by dissolution of lime and zincite, and results from regulatory leaching tests can be misleading because the variable acid neutralization capacity of EAF dusts can lead to very different final leachate pHs (5--12.4). A more informative approach would be to evaluate the total amounts of contaminants available in the long term, and the acid neutralization capacity.

Stegemann, J.A.; Roy, A.; Caldwell, R.J.; Schilling, P.J.; Tittsworth, R.

2000-02-01

393

Investigations on phosphorus recovery and reuse as soil amendment from electric arc furnace slag filters.  

PubMed

Electric arc furnace (EAF) steel slag has been identified as an effective filter material for the removal of phosphorus (P) from both point and non-point sources. To determine the feasibility of land-applying P saturated EAF steel slag this study was undertaken to investigate (i) saturated EAF steel slag material's potential as a P fertilizer or soil amendment and (ii) P desorption and metals leachate from saturated EAF steel slag material to surface runoff. Medicago sativa (alfalfa) was planted in a nutrient depleted washed sand media. Phosphorus was added either as saturated EAF steel slag or as a standard commercial phosphate fertilizer in order to assess the plant availability of the P from saturated EAF steel slag. Four different P application levels were tested: a low (20 lbs acre furrow slice(-1) (5.5 g P m(-3))) two medium (40 and 60 lbs. acre f.s.(-1) (11 and 16.5 g P m(-3))) and a high (120 lbs. acre f.s.(-1) (33 g P m(-3))). The above-ground biomass of half of the plants was harvested after 5 weeks and the second half at 10 weeks. All treatments regardless of the P source used showed high rates of germination. At the first harvest period (5 weeks) significantly higher above-ground biomass (p < 0.01) was seen at the 3 highest P amendment rates in treatments with triple super phosphate fertilizer (TSP) than with EAF steel slag. However, by the second harvest (10 weeks) only the highest amendment rate of TSP showed a significantly higher amount of biomass (p < 0.01), suggesting that EAF steel slag might be an effective slow release P source. In a second experiment, a rain simulator was used to assess desorption of DRP, TP and metals from a saturated and semi-saturated EAF steel slag. The results revealed that the total amounts of DRP and TP released to surface runoff from EAF steel slag were negligible when compared to the total quantities of P retained by this material. Overall the results from this study demonstrated that once the EAF steel slag filter reaches its saturation point, the material could be re-used as soil amendment for the slow release of bioavailable P with minimal risk for loss of P to surface runoff, bringing further benefits to the environment. PMID:20183504

Bird, Simon C; Drizo, Aleksandra

2009-11-01

394

Pilot plant testing of Illinois coal for blast furnace injection. Technical report, September 1--November 30, 1994  

SciTech Connect

The purpose of this study is to evaluate the combustion of Illinois coal in the blast furnace injection process in a new and unique pilot plant test facility. This investigation is significant to the use of Illinois coal in that the limited research to date suggests that coals of low fluidity and moderate to high sulfur and chlorine contents are suitable feedstocks for blast furnace injection. This study is unique in that it is the first North American effort to directly determine the nature of the combustion of coal injected into a blast furnace. It is intended to complete the study already underway with the Armco and Inland steel companies and to demonstrate quantitatively the suitability of both the Herrin No. 6 and Springfield No. 5 coals for blast furnace injection. The main feature of the current work is the testing of Illinois coals at CANMET`s (Canadian Centre for Mineral and Energy Technology) pilot plant coal combustion facility. This facility simulates blowpipe-tuyere conditions in an operating blast furnace, including blast temperature (900 C), flow pattern (hot velocity 200 m/s), geometry, gas composition, coal injection velocity (34 m/s) and residence time (20 ms). The facility is fully instrumented to measure air flow rate, air temperature, temperature in the reactor, wall temperature, preheater coil temperature and flue gas analysis. During this quarter a sample of the Herrin No. 6 coal (IBCSP 112) was delivered to the CANMET facility and testing is scheduled for the week of 11 December 1994. Also at this time, all of the IBCSP samples are being evaluated for blast furnace injection using the CANMET computer model.

Crelling, J.C. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Geology

1994-12-31

395

Induction graphitizing furnace acceptance test report  

NASA Technical Reports Server (NTRS)

The induction furnace was designed to provide the controlled temperature and environment required for the post-cure, carbonization and graphitization processes for the fabrication of a fibrous graphite NERVA nozzle extension. The acceptance testing required six tests and a total operating time of 298 hrs. Low temperature mode operations, 120 to 850 C, were completed in one test run. High temperature mode operations, 120 to 2750 C, were completed during five tests.

1972-01-01

396

Concentration of a Cassegrain solar furnace  

SciTech Connect

A solar furnace comprising a paraboloidal mirror for tracking the sun and a hyperboloidal reflector having one focus in common with the paraboloid is analyzed to determine the geometric concentration of the system. A numerical ray-trace analysis was carried out to study various geometrical configurations of the two reflectors. In particular, the geometric concentration is calculated for the case when the line joining the foci of the hyperboloid and the axis of revolution of the paraboloid are not coincident.

Cobble, M.H.

1981-01-01

397

Temperature Controller for a Solar Furnace  

NASA Technical Reports Server (NTRS)

Relatively-simple movable sheild has been suggested for controlling temperature of solar furnace. Temperature modulator can be set to have collected solar energy fully "on", fully "off" or any intermediate level. Parabolic mirror concentrates Sunlight into receiver. Shade plate that blocks insolation at back of receiver produces shade zone in center of collector. No radiation is returned to receiver from shade zone; only rays falling on other areas of reflecting surface are directed back toward receiver.

Hale, R. R.; Mcdougal, A. R.

1982-01-01

398

Optimized Utility Systems and Furnace Integration  

E-print Network

OPTIMIZED UTILITY SYSTEMS AND FURNACE INTEGRATION A. S. McMullan and H. D. Spriggs, Linnhoff March, Inc., Leesburg, Va. ABSTRACT Conventional process design philosophy usually results in utility systems being designed after process design... defines the Process/Utility interface. Clearly, changing the process design can result in different utility demands and possibly in different utility system designs. This paper presents a procedure, using Pinch Technology, for the simultaneous design...

McMullan, A. S.; Spriggs, H. D.

399

Ultra-high vacuum compatible image furnace  

NASA Astrophysics Data System (ADS)

We report the design of an optical floating-zone furnace for single-crystal growth under ultra-high vacuum (UHV) compatible conditions. The system is based on a commercial image furnace, which has been refurbished to be all-metal sealed. Major changes concern the use of UHV rotary feedthroughs and bespoke quartz-metal seals with metal-O-rings at the lamp stage. As a consequence, the procedure of assembling the furnace for crystal growth is changed completely. Bespoke heating jackets permit to bake the system. For compounds with elevated vapor pressures, the ultra-high vacuum serves as a precondition for the use of a high-purity argon atmosphere up to 10 bar. In the ferromagnetic Heusler compound Cu _2MnAl, the improvements of purity result in an improved stability of the molten zone, grain selection, and, hence, single-crystal growth. Similar improvements are observed in traveling-solvent floating-zone growth of the antiferromagnetic Heusler compound Mn _3Si. These improvements underscore the great potential of optical float-zoning for the growth of high-purity single crystals of intermetallic compounds.

Neubauer, A.; BÅ`uf, J.; Bauer, A.; Russ, B.; Löhneysen, H. v.; Pfleiderer, C.

2011-01-01

400

Ultra-high vacuum compatible image furnace.  

PubMed

We report the design of an optical floating-zone furnace for single-crystal growth under ultra-high vacuum (UHV) compatible conditions. The system is based on a commercial image furnace, which has been refurbished to be all-metal sealed. Major changes concern the use of UHV rotary feedthroughs and bespoke quartz-metal seals with metal-O-rings at the lamp stage. As a consequence, the procedure of assembling the furnace for crystal growth is changed completely. Bespoke heating jackets permit to bake the system. For compounds with elevated vapor pressures, the ultra-high vacuum serves as a precondition for the use of a high-purity argon atmosphere up to 10 bar. In the ferromagnetic Heusler compound Cu(2)MnAl, the improvements of purity result in an improved stability of the molten zone, grain selection, and, hence, single-crystal growth. Similar improvements are observed in traveling-solvent floating-zone growth of the antiferromagnetic Heusler compound Mn(3)Si. These improvements underscore the great potential of optical float-zoning for the growth of high-purity single crystals of intermetallic compounds. PMID:21280840

Neubauer, A; Boeuf, J; Bauer, A; Russ, B; Löhneysen, H v; Pfleiderer, C

2011-01-01

401

Furnace combustion zone temperature control method  

SciTech Connect

This patent describes a method for controlling temperature in a combustion zone in a furnace, independent of flue gas oxygen content. It comprises: supplying combustion air to the furnace for combustion of a fuel therein; providing a plurality of low volume gas flow entry ports to the combustion zone in the furnace with carrier gas continuously flowing through the ports into the combustion zone; selecting a set point value for the combustion zone temperature which, upon the temperature exceeding the set point value, commences generation of a fine water mist external the combustion zone by mist generating means within the carrier gas, the mist flowing into the combustion zone with the carrier gas and reducing temperature within the combustion zone by vaporization therein; and adding a proportionately greater amount of water mist to the carrier gas as the temperature of the combustion zone deviates above the set point value, the amount of water mist added limited by the capacity of the mist generating means, and ceasing the water mist generation upon the combustion zone temperature falling to or below the set point value.

McIntyre, G.C.; Lacombe, R.J.; Forbess, R.G.

1991-05-28

402

Blast furnace granular coal injection project. Annual report, January--December 1995  

SciTech Connect

This annual report describes the Blast Furnace Granular Coal Injection project being implemented at Bethlehem Steel Corporation`s (BSC) Burns Harbor Plant. The project is receiving cost-sharing from the U.S. Department of Energy (DOE), and is being administrated by the Morgantown Energy Technology Center in accordance with the DOE Cooperative Agreement No. DE-FC21-91MC27362. This installation is the first in the United States to employ British Steel technology that uses granular coal to provide part of the fuel requirement of blast furnaces. The project will demonstrate/assess a broad range of technical/economic issues associated with the use of coal for this purpose. To achieve the program objectives, the demonstration project is divided into the following three Phases: (1) Phase I - Design. (2) Phase II - Construction. (3) Phase III - Operation. Preliminary Design (Phase I) began in 1991 with detailed design commencing in 1993. Construction at Burns Harbor (Phase II) began in August 1993 and was completed at the end of 1994. The demonstration test program (Phase III) started in the fourth quarter of 1995.

NONE

1995-05-01

403

The effect of oxide inclusions on the kinetics of the austenite to ferrite transformation in low alloy steel weld metal  

SciTech Connect

Isothermal transformation kinetics of austenite to acicular ferrite and allotriomorphic ferrite were measured in reheated low alloy steel weld deposits with similar weld compositions and austenite grain size but different inclusion characteristics. Accelerated kinetics of transformation to acicular ferrite were observed in weld metal containing coarser and titanium-rich inclusions. In contrast, kinetics of transformation to allotriomorphic ferrite were not influenced by inclusion characteristics, but, rather, by the austenite grain size and carbon concentration.

Babu, S.S.; David, S.A.; Vitek, J.M. [Oak Ridge National Lab., TN (United States); DebRoy, T. [Pennsylvania State Univ., State College, PA (United States)

1994-09-01

404

TiC precipitation induced effect on microstructure and mechanical properties in low carbon medium manganese steel  

Microsoft Academic Search

The precipitation behavior of titanium treated by different processes and its effect on microstructure and mechanical properties has been investigated in low carbon medium manganese steel. It is found that the formed precipitates during both tempering and reheating-quenching processes are TiCs. The size of them mainly ranges from 1 to 18nm and 1 to 36nm, respectively. And tempering treatment especially

Y. Han; J. Shi; L. Xu; W. Q. Cao; H. Dong

405

Reduce Air Infiltration in Furnaces (English/Chinese) (Fact Sheet)  

SciTech Connect

Chinese translation of the Reduce Air Infiltration in Furnaces fact sheet. Provides suggestions on how to improve furnace energy efficiency. Fuel-fired furnaces discharge combustion products through a stack or a chimney. Hot furnace gases are less dense and more buoyant than ambient air, so they rise, creating a differential pressure between the top and the bottom of the furnace. This differential, known as thermal head, is the source of a natural draft or negative pressure in furnaces and boilers. A well-designed furnace (or boiler) is built to avoid air leakage into the furnace or leakage of flue gases from the furnace to the ambient. However, with time, most furnaces develop cracks or openings around doors, joints, and hearth seals. These openings (leaks) usually appear small compared with the overall dimensions of the furnace, so they are often ignored. The negative pressure created by the natural draft (or use of an induced-draft fan) in a furnace draws cold air through the openings (leaks) and into the furnace. The cold air becomes heated to the furnace exhaust gas temperature and then exits through the flue system, wasting valuable fuel. It might also cause excessive oxidation of metals or other materials in the furnaces. The heat loss due to cold air leakage resulting from the natural draft can be estimated if you know four major parameters: (1) The furnace or flue gas temperature; (2) The vertical distance H between the opening (leak) and the point where the exhaust gases leave the furnace and its flue system (if the leak is along a vertical surface, H will be an average value); (3) The area of the leak, in square inches; and (4) The amount of operating time the furnace spends at negative pressure. Secondary parameters that affect the amount of air leakage include these: (1) The furnace firing rate; (2) The flue gas velocity through the stack or the stack cross-section area; (3) The burner operating conditions (e.g., excess air, combustion air temperature, and so on). For furnaces or boilers using an induced-draft (ID) fan, the furnace negative pressure depends on the fan performance and frictional losses between the fan inlet and the point of air leakage. In most cases, it would be necessary to measure or estimate negative pressure at the opening. The amount of air leakage, the heat lost in flue gases, and their effects on increased furnace or boiler fuel consumption can be calculated by using the equations and graphs given in Industrial Furnaces (see W. Trinks et al., below). Note that the actual heat input required to compensate for the heat loss in flue gases due to air leakage would be greater than the heat contained in the air leakage because of the effect of available heat in the furnace. For a high-temperature furnace that is not maintained properly, the fuel consumption increase due to air leakage can be as high as 10% of the fuel input.

Not Available

2011-10-01

406

Torrefied biomasses in a drop tube furnace to evaluate their utility in blast furnaces.  

PubMed

Torrefaction and burning characteristics of bamboo, oil palm, rice husk, bagasse, and Madagascar almond were studied and compared with a high-volatile bituminous coal using a drop tube furnace to evaluate the potential of biomass consumed in blast furnaces. Torrefaction at 250 and 300°C for 1h duration was carried out. Analysis using the ash tracer method indicated that the extent of atomic carbon reduction in the biomasses was less than that of atomic hydrogen and oxygen. Torrefaction also lowered the sulfur content in bamboo and oil palm over 33%. An examination of the R-factor and burnout of the samples suggests that more volatiles were released and a higher burnout was achieved with raw and torrefied biomasses at 250°C than at 300°C; however, torrefaction at 300°C is a feasible operating condition to transform biomass into a solid fuel resembling a high-volatile bituminous coal used for blast furnaces. PMID:22386202

Chen, Wei-Hsin; Du, Shan-Wen; Tsai, Chien-Hsiung; Wang, Zhen-Yu

2012-05-01

407

Nitrogen Control in Electric Arc Furnace Steelmaking by DRI (TRP 0009)  

SciTech Connect

Nitrogen is difficult to remove in electric arc furnace (EAF) steelmaking, requiring the use of more energy in the oxygen steelmaking route to produce low-nitrogen steel. The objective of this work was to determine if the injection of directly reduced iron (DRI) fines into EAFs could reduce the nitrogen content by creating fine carbon monoxide bubbles that rinse nitrogen from the steel. The proposed work included physical and chemical characterization of DRI fines, pilot-scale injection into steel, and mathematical modeling to aid in scale-up of the process. Unfortunately, the pilot-scale injections were unsuccessful, but some full-scale data was obtained. Therefore, the original objectives were met, and presented in the form of recommendations to EAF steelmakers regarding: (1) The best composition and size of DRI fines to use; (2) The amount of DRI fines required to achieve a specific reduction in nitrogen content in the steel; and (3) The injection conditions. This information may be used by steelmakers in techno-economic assessments of the cost of reducing nitrogen with this technology.

Dr. Gordon A. Irons

2004-03-31

408

Characterization of stainless steels melted under high nitrogen pressure  

NASA Astrophysics Data System (ADS)

Mechanical properties of stainless steels increase with increasing nitrogen concentration. Currently, the maximum nitrogen concentration in commercial stainless steels is 0.8 wt pct. In this study, type 304 and 316 stainless steels were melted and cooled in a hot-isostatic-pressur(HIP) furnace using nitrogen as the pressurizing gas, producing alloys with nitrogen concentrations between 1 and 4 wt pct. These nitrogen levels exceeded the alloys’ solubility limits, resulting in the formation of nitride precipitates with several different microstructures. A new phase diagram for high nitrogen stainless steel alloys is proposed. Several properties of these nitrogen stainless steel alloys with chromium nitrides present were studied: tensile strength was proportional to the interstitial nitrogen concentration; hardness, wear, and elastic modules were proportional to the total nitrogen concentration.

Rawers, J. C.; Dunning, J. S.; Asai, G.; Reed, R. P.

1992-07-01

409

Reheating and dangerous relics in pre-big-bang string cosmology  

SciTech Connect

We discuss the mechanism of reheating in pre-big-bang string cosmology and we calculate the amount of moduli and gravitinos produced gravitationally and in scattering processes of the thermal bath. We find that this abundance always exceeds the limits imposed by big-bang nucleosynthesis, and significant entropy production is required. The exact amount of entropy needed depends on the details of the high curvature phase between the dilaton-driven inflationary era and the radiation era. We show that the domination and decay of the zero-mode of a modulus field, which could well be the dilaton, or of axions, suffices to dilute moduli and gravitinos. In this context, baryogenesis can be accommodated in a simple way via the Affleck-Dine mechanism and in some cases the Affleck-Dine condensate could provide both the source of entropy and the baryon asymmetry.

Buonanno, Alessandra; Lemoine, Martin; Olive, Keith A.

2000-10-15

410

Improvement of Dehumidification Performance on Room Air Conditioner Adopting Dehumidification Method Reheated by Refrigeration Cycle  

NASA Astrophysics Data System (ADS)

The ways to increase dehumidification capacity during the dehumidification operation reheated by refrigeration cycle on room air conditioners using R 410A was investigated, keeping electric power consumption lower, noise level lower and outlet air temperature constant. The indoor heat exchanger is divided into a condensing part and an evaporating part by a dehumidification valve which is located between these two heat exchangers. The cooled and dehumidified indoor air is heated by the condensing part. The noise occurred from the two-phase refrigerant flow passing through this valve. So the compressor rotational speed was increased properly to increase dehumidification capacity. Moreover a new dehumidification valve was developed to reduce the refrigerant flow noise. This valve has two expansion processes and each expansion process has plural notch throttles. As the result, 1.5 times dehumidification capacity was gained, keeping lower electric power consumption, lower noise level and constant outlet air temperature.

Nakamura, Hiroo; Funakoshi, Sunao; Yokoyama, Hidenori; Morimoto, Motoo; Saito, Kiyoshi

411

Hypercharged Dark Matter and Direct Detection as a Probe of Reheating  

NASA Astrophysics Data System (ADS)

The lack of new physics at the LHC so far weakens the argument for TeV scale thermal dark matter. On the other hand, heavier, nonthermal dark matter is generally difficult to test experimentally. Here we consider the interesting and generic case of hypercharged dark matter, which can allow for heavy dark matter masses without spoiling testability. Planned direct detection experiments will be able to see a signal for masses up to an incredible 1010 GeV, and this can further serve to probe the reheating temperature up to about 109 GeV, as determined by the nonthermal dark matter relic abundance. The Z-mediated nature of the dark matter scattering may be determined in principle by comparing scattering rates on different detector nuclei, which in turn can reveal the dark matter mass. We will discuss the extent to which future experiments may be able to make such a determination.

Feldstein, Brian; Ibe, Masahiro; Yanagida, Tsutomu T.

2014-03-01

412

Hypercharged dark matter and direct detection as a probe of reheating.  

PubMed

The lack of new physics at the LHC so far weakens the argument for TeV scale thermal dark matter. On the other hand, heavier, nonthermal dark matter is generally difficult to test experimentally. Here we consider the interesting and generic case of hypercharged dark matter, which can allow for heavy dark matter masses without spoiling testability. Planned direct detection experiments will be able to see a signal for masses up to an incredible 1010??GeV, and this can further serve to probe the reheating temperature up to about 109??GeV, as determined by the nonthermal dark matter relic abundance. The Z-mediated nature of the dark matter scattering may be determined in principle by comparing scattering rates on different detector nuclei, which in turn can reveal the dark matter mass. We will discuss the extent to which future experiments may be able to make such a determination. PMID:24679278

Feldstein, Brian; Ibe, Masahiro; Yanagida, Tsutomu T

2014-03-14

413

AISI/DOE Technology Roadmap Program: Behavior of Phosphorus in DRI/HBI During Electric Furnace Steelmaking  

SciTech Connect

Many common scrap substitutes such as direct reduced iron pellets (DRI), hot briquetted iron (HBI), iron carbide, etc., contain significantly higher levels of phosphorus steelmaking for the production of higher quality steels, control of phosphorus levels in the metal will become a concern. This study has developed a more complete understanding of the behavior of phosphorus in DRI during EAF steelmaking, through a thorough investigation of the kinetics and thermodynamics of phosphorus transfer in the EAF based upon laboratory and plant experiments and trials. Laboratory experiments have shown that phosphorus mass transfer between oxide and metallic phases within commercial direct reduced iron pellets occurs rapidly upon melting according to the local equilibrium for these phases. Laboratory kinetic experiments indicate that under certain conditions, phosphorus mass transfer between slag and metal is influenced by dynamic phenomena, which affect the mass transfer coefficient for the reaction and/or the slag metal interfacial area. Plant trials were conducted to directly evaluate the conditions of mass transfer in the electric furnace and to determine the effects of different scrap substitute materials upon the slag chemistry, the behavior of phosphorus in the steel, and upon furnace yield. The data from these trials were also used to develop empirical models for the slag chemistry and furnace temperature as functions of time during a single heat. The laboratory and plant data were used to develop a numerical process model to describe phosphorus transfer in the EAF

Richard J. Frueham; Christopher P. Manning cmanning@bu.edu

2001-10-05

414

New high temperature steels for steam power plants  

SciTech Connect

Development of high efficiency ultra supercritical (USC) steam power plant is based on the availability of improved high temperature steels for key components in the steam cycle i.e: Thick section boiler components and steam lines; turbine rotors, casings, valves and bolts; superheaters; furnace panels. New martensitic high creep strength 9--12%Cr steels like the P91, P92 and P122 allow increased steam parameters in steam headers and steam lines, and similar martensitic steels are used for rotors, casings and valves of advanced steam turbines. The development of these steels have included demonstration of fabricability like welding and bending, fabrication of demonstration components built into existing plants, and the validation of long term creep properties with testing times of more than 30,000 hours. The development work has been made in international projects like the EPRI RP1403, COST 501 and ECCC. The first use of the new steels have followed in USC plants in Europe and Japan, leading to plant efficiencies up to 47%. Superheater steels must have high corrosion and oxidation resistance, and a number of new austenitic steels have been developed for this purpose. Tests are currently running to obtain long term corrosion and oxidation data for design of superheaters in the new steels. Steels for furnace panels need to be welded without post weld heat treatment, and also for this purpose new ferritic and martensitic steels are available. With the materials development described above it is today possible to construct a USC plant with steam parameters 325bar/610 C/630 C/630 C and an efficiency approaching 50%. Future developments in the European THERMIE demonstration project ``Advanced (700 C) PF Power Plant'' will address the use of nickel or cobalt base superalloys for boilers, steam lines and turbines. This may lead to efficiencies in the range 52--55%.

Hald, J.; Nath, B.

1998-07-01

415

Assessment of selected furnace technologies for RWMC waste  

SciTech Connect

This report provides a description and initial evaluation of five selected thermal treatment (furnace) technologies, in support of earlier thermal technologies scoping work for application to the Idaho National Engineering Laboratory Radioactive Waste Management Complex (RWMC) buried wastes. The cyclone furnace, molten salt processor, microwave melter, ausmelt (fuel fired lance) furnace, and molten metal processor technologies are evaluated. A system description and brief development history are provided. The state of development of each technology is assessed, relative to treatment of RWMC buried waste.

Batdorf, J.; Gillins, R. [Science Applications International Corp., Idaho Falls, ID (United States); Anderson, G.L. [EG and G Idaho, Inc., Idaho Falls, ID (United States)

1992-03-01

416

Comparison of Predictive Control Methods for High Consumption Industrial Furnace  

PubMed Central

We describe several predictive control approaches for high consumption industrial furnace control. These furnaces are major consumers in production industries, and reducing their fuel consumption and optimizing the quality of the products is one of the most important engineer tasks. In order to demonstrate the benefits from implementation of the advanced predictive control algorithms, we have compared several major criteria for furnace control. On the basis of the analysis, some important conclusions have been drawn. PMID:24319354

2013-01-01

417

5. Photocopied August 1978. FRONT OF A HORRY ROTARY FURNACE, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. Photocopied August 1978. FRONT OF A HORRY ROTARY FURNACE, SHOWING INTERIOR ELECTRODES. THE RAW MATERIALS FOR CALCIUM CARBIDE PRODUCTION--LIMESTONE AND COKE--WERE FED BY HOPPERS PLACED BETWEEN THESE ELECTRODES INTO THE ELECTRIC ARC. THE REMOVABLE PLATES ON THE EXTERNAL CIRCUMSTANCE OF THE HORRY FURNACE ARE SHOWN ON THE FIRST THREE FURNACES. (M) - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

418

3D Numerical Analysis of the Arc Plasma Behavior in a Submerged DC Electric Arc Furnace for the Production of Fused MgO  

NASA Astrophysics Data System (ADS)

A three dimensional steady-state magnetohydrodynamic model is developed for the arc plasma in a DC submerged electric arc furnace for the production of fused MgO. The arc is generated in a small semi-enclosed space formed by the graphite electrode, the molten bath and unmelted raw materials. The model is first used to solve a similar problem in a steel making furnace, and the calculated results are found to be in good agreement with the published measurements. The behavior of arcs with different arc lengths is also studied in the furnace for MgO production. From the distribution of the arc pressure on the bath surface it is shown that the arc plasma impingement is large enough to cause a crater-like depression on the surface of the MgO bath. The circulation of the high temperature air under the electrode may enhance the arc efficiency, especially for a shorter arc.

Wang, Zhen; Wang, Ninghui; Li, Tie; Cao, Yong

2012-04-01

419

A 1800 K furnace designed for in situ synchrotron microtomography.  

PubMed

A radiation furnace that covers the temperature range from room temperature up to 1800 K has been designed and constructed for in situ synchrotron microtomography. The furnace operates under a vacuum or under any inert gas atmosphere. The two 1000 W halogen heating lamps are water- and air-cooled. The samples are located at the focus of these lamp reflectors on a rotary feedthrough that is connected to a driving rotation stage below the furnace. The X-ray beam penetrates the furnace through two X-ray-transparent vacuum-sealed windows. Further windows can be used for temperature control, sample changing and gas inflow and outflow. PMID:19535867

Grupp, R; Henkel, F; Nöthe, M; Banhart, J; Kieback, B; Haibel, A

2009-07-01

420

12. ANGLED VIEW OF THE SCOTT FURNACE WITH PRIMARY CONDENSER ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. ANGLED VIEW OF THE SCOTT FURNACE WITH PRIMARY CONDENSER AND SOUTH SECONDARY CONDENSER IN BACKGROUND, LOOKING SOUTHWEST. - Mariscal Quicksilver Mine & Reduction Works, Terlingua, Brewster County, TX

421

VIEW OF MARISCAL WORKS INCLUDING (POSSIBLE SOOT FURNACE), FOREGROUND, CONDENSERS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF MARISCAL WORKS INCLUDING (POSSIBLE SOOT FURNACE), FOREGROUND, CONDENSERS AND ORE BIN FOUNDATION ABOVE, LOOKING NORTHWEST. - Mariscal Quicksilver Mine & Reduction Works, Terlingua, Brewster County, TX

422

Biological Kraft Chemical Recycle for Augmentation of Recovery Furnace Capacity  

SciTech Connect

The chemicals used in pulping of wood by the kraft process are recycled in the mill in the recovery furnace, which oxidizes organics while simultaneously reducing sulfate to sulfide. The recovery furnace is central to the economical operation of kraft pulp mills, but it also causes problems. The total pulp production of many mills is limited by the recovery furnace capacity, which cannot easily be increased. The furnace is one of the largest sources of air pollution (as reduced sulfur compounds) in the kraft pulp mill.

Stuart E. Strand

2001-12-06

423

Recycling galvanized steel: Operating experience and benefits  

SciTech Connect

In response to the increase in consumption of galvanized steel for automobiles in the last decade and the problems associated with remelting larger quantities of galvanized steel scrap, a process is being developed to separate and recover the steel and zinc from galvanized ferrous scrap. The zinc is dissolved from the scrap in hot caustic using anodic assistance and is recovered electrolytically as dendritic powder. The dezinced ferrous scrap is rinsed and used directly. The process is effective for zinc, lead, and aluminum removal on loose and baled scrap and on all types of galvanized steel. The process has been pilot tested for batch treatment of 900 tonnes of mostly baled scrap. A pilot plant to continuously treat loose scrap, with a design capacity of 48,000 tonnes annually, has been in operation in East Chicago, Indiana since early in 1993. The first 450 t of scrap degalvanized in the pilot plant have residual zinc below 0.01% and sodium dragout below 0.01%. Use of degalvanized steel scrap decreases raw materials, environmental compliance, and opportunity costs to steel- and iron-makers. Availability of clean degalvanized scrap may enable integrated steel producers to recycle furnace dusts to the sinter plant and EAF shops to produce flat products without use of high quality scrap alternatives such as DRI, pig iron, or iron carbide. Recycling the components of galvanized steel scrap saves primary energy, decreases zinc imports, and adds value to the scrap. The quantities of zinc available by the year 2000 from prompt and obsolete automotive scrap win approach 25% of zinc consumed in the major automotive production centers of the world. Zinc recycling from galvanized steel scrap, either before or after scrap melting, will have to be implemented.

Dudek, F.J.; Daniels, E.J. [Argonne National Lab., IL (United States); Morgan, W.A. [Metal Recovery Industries, Inc., East Chicago, IN (United States)

1993-08-01

424

Welding High Strength Modern Line Pipe Steel  

NASA Astrophysics Data System (ADS)

The effect of modern mechanized girth welding on high strength line pipe has been investigated. The single cycle grain coarsened heat affected zone in three grade 690 line pipe steels and a grade 550 steel has been simulated using a Gleeble thermo-mechanical simulator. The continuous cooling transformation diagrams applicable to the grain coarsened heat affected zone resulting from a range of heat inputs applicable to modern mechanized welding have been established by dilatometry and metallography. The coarse grained heat affected zone was found to transform to lath martensite, bainite, and granular bainite depending on the cooling rate. The impact toughness of the steels was measured using Charpy impact toughness and compared to the toughness of the grain coarsened heat affected zone corresponding to a welding thermal cycle. The ductile to brittle transition temperature was found to be lowest for the steel with the highest hardenability. The toughness resulting from three different thermal cycles including a novel interrupted intercritically reheated grain coarsened (NTR ICR GC HAZ) that can result from dual torch welding at fast travel speed and close torch spacing have been investigated. All of the thermally HAZ regions showed reduced toughness that was attributed to bainitic microstructure and large effective grain sizes. Continuous cooling transformation diagrams for five weld metal chemistries applicable to mechanized pulsed gas metal arc welding of modern high strength pipe steel (SMYS>550 MPa) have been constructed. Welds at heat inputs of 1.5 kJmm-1 and 0.5 kJmm-1 have been created for simulation and analysis. Dilatometric analysis was performed on weld metal specimens cut from single pass 1.5 kJmm-1 as deposited beads. The resulting microstructures were found to range from martensite to polygonal ferrite. There is excellent agreement between the simulated and as deposited weld metal regions. Toughness testing indicates improved energy absorption at -20 °C with increased cooling time.

Goodall, Graeme Robertson

425

Exothermic furnace module development. [space processing  

NASA Technical Reports Server (NTRS)

An exothermic furnace module was developed to rapidly heat and cool a 0.820-in. (2.1 cm) diameter by 2.75-in. (7.0 cm) long TZM molybdenum alloy crucible. The crucible contains copper, oxygen, and carbon for processing in a low-g environment. Peak temperatures of 1270 C were obtainable 3.5 min after start of ignition, and cooling below 950 C some 4.5 min later. These time-temperature relationships were conditioned for a foam-copper experiment, Space Processing Applications Rocket experiment 77-9, in a sounding rocket having a low-g period of 5 min.

Darnell, R. R.; Poorman, R. M.

1982-01-01

426

High velocity combustion furnace and burner  

SciTech Connect

A new high-velocity combustion system for heat-treating or forging furnaces improves upon prior designs in that it needs only a small combustion chamber and that several nozzles can be housed in a common air manifold. The combustion air is sufficiently pressurized to create a high flue-gas velocity that causes a backpressure within the combustion chamber, thus reducing the volume of space required in the chamber, bringing the refractory closer to the work piece, shortening the heat-treating time, and increasing the thermal load on the work pieces.

McElroy, J.G.

1982-01-05

427

Fracture initiation by local brittle zones in weldments of quenched and tempered structural alloy steel plate  

SciTech Connect

The heat-affected zone (HAZ) embrittlement of an API 2Y Grade 50T quenched and tempered offshore structural steel plate, welded by the submerged-arc process at a heat input of 4.5 kJ/mm, was investigated from the viewpoint of identifying the local brittle zone (LBZ) microstructure and the metallurgical factors associated with its formation. Microstructural and fractographic analysis showed the LBZ microstructure to be dual phase martensite-austenite (M-A) constituent. The formation of M-A constituent was found to be related to microstructural banding of the hot-rolled base plate. When the banded base plate was welded, M-A constituent formed only within the band microstructure which penetrated the intercritically-reheated coarse-grain HAZ (IRCGHAZ). The chemistry of the band microstructure in conjunction with the thermal cycle of the IRCGHAZ provided the critical conditions for the formation of M-A constituent in the API 2Y Grade 50T steel investigated. The influence of local brittle zones (i.e., M-A constituent) on the HAZ fracture toughness was evaluated by means of Crack-Tip Opening Displacement (CTOD) tests. These tests showed the steel to suffer embrittlement when the fatigue precrack sampled an intercritically-reheated coarse-grain HAZ which contained M-A constituent, confirming that M-A constituent is the major microstructural factor controlling the HAZ toughness of this particular steel.

Kenney, K.L.; Reuter, W.G. [Idaho National Engineering Lab., Idaho Falls, ID (United States); Reemsnyder, H.S. [Bethlehem Steel Corp., PA (United States); Matlock, D.K. [Colorado School of Mines, Golden, CO (United States). Dept. of Metallurgical and Materials Engineering

1997-12-31

428

A study of the processes during high temperature oxidation that control surface hot shortness in copper-containing low carbon steels  

NASA Astrophysics Data System (ADS)

Copper is a problematic residual element in electric arc furnace steel production because it leads to "surface hot shortness," a cracking defect that occurs during hot rolling of steel. The cracking arises from a liquid, copper-rich phase that penetrates into and embrittles the austenite grain boundaries. The liquid forms because copper is nobler than iron and enriches at the oxide/metal interface during oxidation of iron after casting and reheating prior to hot rolling. This cracking can be reduced or eliminated by controlling the distribution of the copper-rich layer, i.e. preventing it from penetrating down the austenite grain boundaries. This study investigated the effect of alloy chemistry on the oxidation behavior and copper-rich liquid phase evolution. Alloy compositions were selected such that effects of copper, nickel, and reactive impurities (manganese, aluminum, and silicon) can be isolated. Industrially produced low carbon steels with varying copper, nickel and silicon contents were also studied. Alloys were oxidized in air or water vapor for times up to one hour at 1150°C. Oxidizing heat treatments were conducted in a thermogravimetric setup where the weight change could be measured during oxidation. Scanning electron microscopy was used to investigate in detail the oxide/metal interfaces. The modeling work focused on describing the enrichment and subsequent growth of the copper-rich layer. A fixed grid finite difference model was developed that predicts the evolution of the enriched region from given oxidation kinetics. The model predictions were validated under a variety of conditions using an iron - 0.3 wt% copper alloy. Deviations from the model predictions in these alloys suggest a critical amount of separated copper is necessary for substantial grain boundary penetration to occur and the required amount decreases when the gas contains water vapor. The parabolic oxidation rate for the iron-copper alloy did not differ from that of pure iron, but the parabolic rate for the nickel-containing alloys decreased by a factor of two. The microstructure of the iron-copper alloy consisted of a thin, copper-rich layer at the oxide/metal interface. Both nickel-containing alloys had perturbed oxide/metal interfaces consisting of alternating solid/liquid regions. The perturbed interfaces arise from unequal copper and nickel diffusivities in the ternary alloy. These diffusion effects are discussed in detail. The oxidation rate decrease is justified by the interface microstructure assuming that iron can only be rapidly supplied to the oxide through the liquid regions. Additions of manganese or aluminum to an iron-copper-nickel alloy did not lead to significant changes in behavior. Oxidation kinetics, amount of separated material, and interface roughness were unchanged. There was slightly more material occluded in the samples containing manganese and aluminum due to increased internal oxidation. These internal oxides do not affect the oxidation behavior because manganese can dissolve in wustite and the aluminum internal oxides are extremely small and heterogeneously dispersed near the oxide/metal interface. Additions of silicon, however, to an iron-copper-nickel alloy led to a significant decrease in oxidation rate, amount separated, and amount occluded. The differences in behavior are attributed to the formation of a fayalite layer at the oxide/metal interface. This layer blocks iron transport in the wustite layer, decreasing the oxidation rate and therefore the enrichment rate. Formation of the fayalite layer was found not to depend on the amount of nickel in the samples. The results above were then used to explain the oxidation behavior of low carbon steels containing copper, nickel, silicon, manganese, and aluminum. Steels containing high amounts of silicon had lower oxidation rates and higher amounts occluded. The amount of occluded material is much higher in the steels than in the iron-copper-nickel-silicon alloys. This is attributed to competition among the easily oxidizable impurities resulting in smal

Webler, Bryan A.

429

Mercury in dumped blast furnace sludge.  

PubMed

Blast furnace sludge (BFS) is a waste generated in the production of pig iron and was dumped in sedimentation ponds. Sixty-five samples from seven BFS locations in Europe were investigated regarding the toxic element mercury (Hg) for the first time. The charge material of the blast furnace operations revealed Hg contents from 0.015 to 0.097mgkg(-1). In comparison, the Hg content of BFS varied between 0.006 and 20.8mgkg(-1) with a median of 1.63mgkg(-1), which indicates enrichment with Hg. For one site with a larger sample set (n=31), Hg showed a stronger correlation with the total non-calcareous carbon (C) including coke and graphite (r=0.695; n=31; p<0.001). It can be assumed that these C-rich compounds are hosting phases for Hg. The solubility of Hg was rather low and did not exceed 0.43% of total Hg. The correlation between the total Hg concentration and total amount of NH4NO3-soluble Hg was relatively poor (r=0.496; n=27; p=0.008) indicating varying hazard potentials of the different BFS. Finally, BFS is a mercury-containing waste and dumped BFS should be regarded as potentially mercury-contaminated sites. PMID:24290303

Földi, Corinna; Dohrmann, Reiner; Mansfeldt, Tim

2014-03-01

430

Global simulation of a silicon Czochralski furnace  

NASA Astrophysics Data System (ADS)

To understand the characteristics of the Czochralski (Cz) furnace for the single-crystal growth of silicon, a set of global analyses of momentum, heat and mass transfer in small Cz furnaces (crucible diameter: 7.2 cm, crystal diameter: 3.5 cm, operated in a 10 Torr argon flow environment) is carried out using the finite-element method. The global analysis assumes a pseudosteady axisymmetric state with laminar flow, equilibrium relations at the melt/silica interface and vapor-liquid chemical equilibrium at the melt/gas interface, as well as the segregation coefficient of unity at the melt/crystal interface. Convective and conductive heat transfers, radiative heat transfer between diffuse surfaces and the Navier-Stokes equations for gas and melt phases are all combined and solved together. Thus, the velocities and temperatures obtained are used to calculate the oxygen concentrations. The global analysis code is effectively used to discuss the influences of the Marangoni effect and a gas guide (or a heat shield) placed between the crucible and the crystal. The results indicate that the gas guide reduces the heater power and changes the melt flow pattern and oxygen transport. The melt flow pattern is strongly dependent on the Marangoni effect and gas flow near the surface, and changes the oxygen concentration significantly. This analysis reveals the importance and effectiveness of global analysis.

Li, Mingwei; Li, Yourong; Imaishi, Nobuyuki; Tsukada, Takao

2002-01-01

431

Thermodynamic Modeling of Zinc Speciation in Electric Arc Furnace Dust  

NASA Astrophysics Data System (ADS)

The remelting of automobile scrap, containing galvanized steel, in an electric arc furnace (EAF) results in the generation of a dust, which contains considerable amounts of zinc and other metals. Typically, the amount of zinc is of significant commercial value, but the recovery of this metal can be hindered by the varied speciation of zinc. The majority of the zinc exists as zincite (ZnO) and zinc ferrite (ZnFe2O4) or ferritic spinels ((Zn x Mn y Fe1-x-y )Fe2O4), but other zinccontaining species such as zinc chloride, zinc hydroxide chlorides, hydrated zinc sulphates and zinc silicates have also been identified. There is a scarcity of research literature on the thermodynamic aspects of the formation of these zinc-containing species, in particular, the minor zinc-containing species. Therefore, in this study, the equilibrium module of HSC Chemistry® 6.1 was utilized to calculate the types and the amounts of the zinc-containing species. The variables studied were: the gas composition, the temperature and the dust composition. At high temperatures, zincite forms via the reaction of zinc vapour with oxygen gas and the zinc-manganese ferrites form as a result of the reaction of iron-manganese particles with zinc vapour and oxygen. At intermediate temperatures, zinc sulphates are produced through the reaction of zinc oxide and sulphur dioxide gas. As room temperature is approached, zinc chlorides and fluorides form by the reaction of zinc oxide with hydrogen chloride and hydrogen fluoride gases, respectively. Zinc silicate likely forms via the high temperature reaction of zinc vapour and oxygen with silica. In the presence of excess water and as room temperature is approached, the zinc sulphates, chlorides and fluorides can become hydrated.

Pickles, Chris A.

2011-04-01

432

Volatilisation and oxidation of aluminium scraps fed into incineration furnaces  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer Aluminium packaging partitioning in MSW incineration residues is evaluated. Black-Right-Pointing-Pointer The amount of aluminium packaging recoverable from the bottom ashes is evaluated. Black-Right-Pointing-Pointer Aluminium packaging oxidation rate in the residues of MSW incineration is evaluated. Black-Right-Pointing-Pointer 80% of aluminium cans, 51% of trays and 27% of foils can be recovered from bottom ashes. - Abstract: Ferrous and non-ferrous metal scraps are increasingly recovered from municipal solid waste incineration bottom ash and used in the production of secondary steel and aluminium. However, during the incineration process, metal scraps contained in the waste undergo volatilisation and oxidation processes, which determine a loss of their recoverable mass. The present paper evaluates the behaviour of different types of aluminium packaging materials in a full-scale waste to energy plant during standard operation. Their partitioning and oxidation level in the residues of the incineration process are evaluated, together with the amount of potentially recoverable aluminium. About 80% of post-consumer cans, 51% of trays and 27% of foils can be recovered through an advanced treatment of bottom ash combined with a melting process in the saline furnace for the production of secondary aluminium. The residual amount of aluminium concentrates in the fly ash or in the fine fraction of the bottom ash and its recovery is virtually impossible using the current eddy current separation technology. The average oxidation levels of the aluminium in the residues of the incineration process is equal to 9.2% for cans, 17.4% for trays and 58.8% for foils. The differences between the tested packaging materials are related to their thickness, mechanical strength and to the alloy.

Biganzoli, Laura, E-mail: laura.biganzoli@mail.polimi.it [Politecnico di Milano, Piazza L. Da Vinci 32, 20133 Milano (Italy); Gorla, Leopoldo; Nessi, Simone; Grosso, Mario [Politecnico di Milano, Piazza L. Da Vinci 32, 20133 Milano (Italy)

2012-12-15

433

When Your Furnace Kicks On, Be Sure Poison Gas Isn't Coming Out  

MedlinePLUS

WHEN YOUR FURNACE KICKS ON, BE SURE POISON GAS ISN’T COMING OUT Every winter when the ... drops, your furnace can become a silent killer. Gas- and oil-burning furnaces produce carbon monoxide (CO). ...

434

16 CFR 305.12 - Labeling for central air conditioners, heat pumps, and furnaces.  

Code of Federal Regulations, 2010 CFR

...Labeling for central air conditioners, heat pumps, and furnaces. 305.12 Section 305...Labeling for central air conditioners, heat pumps, and furnaces. (a) Layout . All...labels for central air conditioners, heat pumps, and furnaces (including...

2010-01-01

435

40 CFR 424.50 - Applicability; description of the other calcium carbide furnaces subcategory.  

Code of Federal Regulations, 2010 CFR

...Applicability; description of the other calcium carbide furnaces subcategory. 424...MANUFACTURING POINT SOURCE CATEGORY Other Calcium Carbide Furnaces Subcategory § 424.50 Applicability; description of the other calcium carbide furnaces subcategory....

2010-07-01

436

40 CFR 424.50 - Applicability; description of the other calcium carbide furnaces subcategory.  

Code of Federal Regulations, 2011 CFR

...Applicability; description of the other calcium carbide furnaces subcategory. 424...MANUFACTURING POINT SOURCE CATEGORY Other Calcium Carbide Furnaces Subcategory § 424.50 Applicability; description of the other calcium carbide furnaces subcategory....

2011-07-01

437

40 CFR 424.50 - Applicability; description of the other calcium carbide furnaces subcategory.  

Code of Federal Regulations, 2013 CFR

...Applicability; description of the other calcium carbide furnaces subcategory. 424...MANUFACTURING POINT SOURCE CATEGORY Other Calcium Carbide Furnaces Subcategory § 424.50 Applicability; description of the other calcium carbide furnaces subcategory....

2013-07-01

438

40 CFR 424.50 - Applicability; description of the other calcium carbide furnaces subcategory.  

Code of Federal Regulations, 2014 CFR

...Applicability; description of the other calcium carbide furnaces subcategory. 424...MANUFACTURING POINT SOURCE CATEGORY Other Calcium Carbide Furnaces Subcategory § 424.50 Applicability; description of the other calcium carbide furnaces subcategory....

2014-07-01

439

40 CFR 424.50 - Applicability; description of the other calcium carbide furnaces subcategory.  

Code of Federal Regulations, 2012 CFR

...Applicability; description of the other calcium carbide furnaces subcategory. 424...MANUFACTURING POINT SOURCE CATEGORY Other Calcium Carbide Furnaces Subcategory § 424.50 Applicability; description of the other calcium carbide furnaces subcategory....

2012-07-01

440

Power quality analysis and improvement of DC arc furnace load  

Microsoft Academic Search

In this paper, the power quality problems of a DC arc furnace load are investigated. An 18-pulse converter is used to provide the DC currents to the furnace. The power quality problems concerned are the harmonics and voltage flicker (voltage fluctuation). Field measurement is used to reveal the harmonic distributions of the rectifiers under balanced and unbalanced conditions. The effect

Tsu-Hsun Fu; Chi-Jui Wu

2002-01-01

441

Inexpensive high-temperature furnace for thermocouple calibration  

NASA Technical Reports Server (NTRS)

New furnace calibrates unknown thermocouple by comparing its electrical output to a reference thermocouple /previously calibrated by optical pyrometry/, as both are heated simultaneously. Thermocouples may be radioactive, thus heat source must be accessible by remote manipulation and inspection measurements. Advantages of furnace operation are cited.

Gracey, C. M.; Hoff, R. G.

1971-01-01

442

RELEVANCE OF FUEL PARAMETERS FOR OPERATION CONDITIONS OF BIOMASS FURNACES  

Microsoft Academic Search

Worldwide biomass ranks fourth as an energy source and over 90% of the generated bio-energy are produced in biomass furnaces. The recent development in biomass combustion technology has led to improvement of efficiency and significant reduction of emissions from modern conversion installations. However, the operation and maintenance of biomass furnaces requires detailed understanding of the complex burning process. There is

Rafal Strzalka; Roman Ulbrich; Ursula Eicker; Ömer Gül

443

8. VIEW OF FOUNDRY INDUCTION FURNACES, MODULE J. THE FOUNDRY ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. VIEW OF FOUNDRY INDUCTION FURNACES, MODULE J. THE FOUNDRY CASTING PROCESS WAS CONDUCTED IN A VACUUM. PLUTONIUM METAL WAS MELTED IN ONE OF FOUR ELECTRIC INDUCTION FURNACES TO FORM INGOTS. - Rocky Flats Plant, Plutonium Manufacturing Facility, North-central section of Plant, just south of Building 776/777, Golden, Jefferson County, CO

444

RESIDENTIAL OIL FURNACE SYSTEM OPTIMIZATION--PHASE II  

EPA Science Inventory

The report describes the second of a two-phase investigation into ways to improve the air pollutant emission and thermal efficiency characteristics of residential oil furnaces. A prototype, low-emission, warm-air furnace (designed in Phase I to embody a number of burner and combu...

445

STRIP TEMPERATURE IN A METAL COATING LINE ANNEALING FURNACE  

E-print Network

STRIP TEMPERATURE IN A METAL COATING LINE ANNEALING FURNACE Mark McGuinness1 and Stephen Taylor2 We continuously through the furnace, to certain temperatures and then cooling it, resulting in a change prior to being coated, by heating to a predeter- mined temperature for a definite time. Annealing

McGuinness, Mark

446

41. INTERIOR VIEW, LOOKING WEST, WITH GREY IRON HOLDING FURNACE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

41. INTERIOR VIEW, LOOKING WEST, WITH GREY IRON HOLDING FURNACE AND AN IRON POUR IN PROCESS. MOLTEN DUCTILE IRON IS POURED FROM THIS 25-TON HOLDING FURNACE INTO LADLES FOR TRANSPORT TO CASTING STATIONS - Stockham Pipe & Fittings Company, Grey Iron Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

447

8. INTERIOR VIEW, LOOKING WEST, WITH GREY IRON HOLDING FURNACES ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. INTERIOR VIEW, LOOKING WEST, WITH GREY IRON HOLDING FURNACES AND AN IRON POUR IN PROCESS, CUPOLA TENDER RICHARD SLAUGHTER SUPERVISING THE POUR. MOLTEN DUCTILE IRON IS POURED FROM THIS 25-TON HOLDING FURNACE INTO LADLES FOR TRANSPORT TO CASTING STATIONS. - Stockham Pipe & Fittings Company, Grey Iron Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

448

7. INTERIOR VIEW, LOOKING WEST, WITH GREY IRON HOLDING FURNACE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. INTERIOR VIEW, LOOKING WEST, WITH GREY IRON HOLDING FURNACE AND AN IRON POUR IN PROCESS. MOLTEN DUCTILE IRON IS POURED FROM THIS 25-TON HOLDING FURNACE INTO LADLES FOR TRANSPORT TO CASTING STATIONS. - Stockham Pipe & Fittings Company, Grey Iron Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

449

42. INTERIOR VIEW, LOOKING WEST, WITH GREY IRON HOLDING FURNACE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

42. INTERIOR VIEW, LOOKING WEST, WITH GREY IRON HOLDING FURNACE AND AN IRON POUR IN PROCESS. MOLTEN DUCTILE IRON IS POURED FROM THIS 25-TON HOLDING FURNACE INTO LADLES FOR TRANSPORT TO CASTING STATIONS - Stockham Pipe & Fittings Company, Grey Iron Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

450

EMISSIONS FROM OUTDOOR WOOD-BURNING RESIDENTIAL HOT WATER FURNACES  

EPA Science Inventory

The report gives results of measurements of emissions from a single-pass and a double-pass furnace at average heat outputs of 15,000 and 30,000 Btu/hr (4.4 and 8.8 kW) while burning typical oak cordwood fuel. One furnace was also tested once at each heat output while fitted with ...

451

Effect of Combustion Air Preheat on a Forged Furnace Productivity  

E-print Network

A basic thermal analysis of a gas fired forge furnace can determine the fuel savings from exhaust energy recovery/combustion air preheat on a furnace operating at a single condition, for example, high fire. What this analysis is not able...

Ward, M. E.; Bohn, J.; Davis, S. R.; Knowles, D.

1984-01-01

452

ELECTRIC FURNACES TILT AROUND A PIVOT UNDER THE SPOUT TO ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ELECTRIC FURNACES TILT AROUND A PIVOT UNDER THE SPOUT TO FILL BULL LADLES BELOW THE CHARGING DECK. THE REAR VIEW OF A POURING ELECTRIC FURNACE FROM THE CHARGING DECK IS SHOWN HERE. - Southern Ductile Casting Company, Melting, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

453

NORTH END OF DOUBLE FURNACE AND CAST AND ENGINE SHED, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

NORTH END OF DOUBLE FURNACE AND CAST AND ENGINE SHED, WITH BLOWER HOUSE TO THE EAST AND CHARGING BRIDGE AND TRESSLE TO THE WEST, LOOKING SOUTH-SOUTHEAST. - Tannehill Furnace, 12632 Confederate Parkway, Tannehill Historical State Park, Bucksville, Tuscaloosa County, AL

454

Artificial neural networks in predicting current in electric arc furnaces  

NASA Astrophysics Data System (ADS)

The paper presents a study of the possibility of using artificial neural networks for the prediction of the current and the voltage of Electric Arc Furnaces. Multi-layer perceptron and radial based functions Artificial Neural Networks implemented in Matlab were used. The study is based on measured data items from an Electric Arc Furnace in an industrial plant in Romania.

Panoiu, M.; Panoiu, C.; Iordan, A.; Ghiormez, L.

2014-03-01

455

COMPUTER-ASSISTED FURNACE ATOMIC ABSORPTION SPECTROMETRIC ANALYSIS  

EPA Science Inventory

The use of furnace atomic absorption instrumentation with a turnkey chromatography data system is described. A simple addition of relays to the furnace power supply allows for automatic start-up of A/D conversion and spectrophotometer zeroing at the proper time. Manipulations inv...

456

DEMONSTRATION BULLETIN: CYCLONE FURNACE SOIL VITRI- FICATION TECHNOLOGY - BABCOCK & WILCOX  

EPA Science Inventory

Babcock and Wilcox's (B&W) cyclone furnace is an innovative thermal technology which may offer advantages in treating soils containing organics, heavy metals, and/or radionuclide contaminants. The furnace used in the SITE demonstration was a 4- to 6-million Btu/hr pilot system....

457

Experimenting with concentrated sunlight using the DLR solar furnace  

Microsoft Academic Search

The high flux solar furnace that is operated by the Deutsche Forschungsanstalt für Luft- und Raumfahrt (DLR) at Cologne was inaugurated in June 1994 and we are now able to look back onto one year of successful operation. The solar furnace project was founded by the government of the State Northrhine Westfalia within the Study Group AG Solar. The optical

A. Neumann; U. Groer

1996-01-01

458

Improvements in blast furnace operation at AHMSA Monclova  

SciTech Connect

Following the privatization of Altos Hornos de Mexico, S.A. de C.V. (AHMSA) in Nov. 1991, four areas were chosen to improve blast furnace performance and hot metal costs. These areas included improvement of pellet quality, start of oil-gas co-injection, improved control of gas flow in the blast furnace and start of monitoring program to predict the remaining life of the hearth of No. 5 blast furnace. These efforts resulted in the following improvements in the first half of 1992: Production level increased to 2.4 tonnes/cu metre/24 hr with a 1992 annual production record from No. 5 furnace of 1.639 million tonnes; Coke rates decreased by 60 kg/tonne, half of which was due to process improvements and the other half to injection of oil; Silicon standard deviations decreased from 0.22% in 1991 to 0.20% in 1992; Hot metal costs decreased by 10.6%; and The major reline of No. 5 furnace postponed by at least 1.5 years. The improvement of the blast furnace process was not limited to the larger No. 5 furnace. Similar tends can be observed with No. 4 furnace which will also be equipped with oil injection. For the future, programs have been prepared to increase injection rates, improve casthouse operation and increase process stability.

Morales, J.M.; Dominguez, H. (Altos Hornos de Mexico S.A. de C.V., Monclova (Mexico). Monclova Works); Geerdes, M. (Hoogovens Technical Services B.V., Monclova (Mexico))

1994-10-01

459

Hydrogen-atmosphere induction furnace has increased temperature range  

NASA Technical Reports Server (NTRS)

Improved hydrogen-atmosphere induction furnace operates at temperatures up to 5,350 deg F. The furnace heats up from room temperature to 4,750 deg F in 30 seconds and cools down to room temperature in 2 minutes.

Caves, R. M.; Gresslin, C. H.

1966-01-01

460

Blast-furnace performance with coal-dust injection  

SciTech Connect

For the blast furnace shop at OAO Alchevskii Metallurgicheskii Kombinat (AMK) the injection of pulverized fuel is promising. Preliminary steps toward its introduction are underway, including analytical research. In this context, blast furnace performance when using pulverized coal is calculated in this study.

G.G. Vasyura [OAO Alchevskii Metallurgicheskii Kombinat, Alchevsk (Russian Federation)

2007-07-01

461

11. VIEW OF THE MANIPULATOR AND THE PARTS HEATING FURNACE. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. VIEW OF THE MANIPULATOR AND THE PARTS HEATING FURNACE. THE PARTS OR METALS WERE HEATED PRIOR TO BEING PRESSED. THE MANIPULATOR ARM WAS USED TO INSERT AND REMOVE PARTS OR METALS FROM THE FURNACE. (2/9/79) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

462

3D Numerical Analysis of the Arc Plasma Behavior in a Submerged DC Electric Arc Furnace for the Production of Fused MgO  

Microsoft Academic Search

A three dimensional steady-state magnetohydrodynamic model is developed for the arc plasma in a DC submerged electric arc furnace for the production of fused MgO. The arc is generated in a small semi-enclosed space formed by the graphite electrode, the molten bath and unmelted raw materials. The model is first used to solve a similar problem in a steel making

Wang Zhen; Wang Ninghui; Li Tie; Cao Yong

2012-01-01

463

Behavior of nitrogen in a nitrogen-containing chromium-manganese steel during electroslag remelting  

NASA Astrophysics Data System (ADS)

Electroslag remelting of a high-alloyed steel with high contents of nitrogen, chromium, and manganese in an electroslag furnace has been studied. CaF2-MgO-SiO2 slag developed at TsNIITMASh and allowing remelting process at a temperature of 1520-1560°C is used as a flux. It is found that electroslag remelting of high-alloyed steels with a high nitrogen concentration does not change the nitrogen content.

Linchevskii, B. V.; Rigina, L. G.; Takhirov, A. A.

2013-06-01

464

Effects of experimental reheating of natural basaltic ash at different temperatures and redox conditions  

NASA Astrophysics Data System (ADS)

A set of experiments have been performed on volcanic materials from Etna, Stromboli and Vesuvius in order to evaluate how the exposure to thermal and redox conditions close to that of active craters affects the texture and composition of juvenile pyroclasts. Selected samples were placed within a quartz tube, in presence of air or under vacuum, and kept at T between 700 and 1,130 °C, for variable time (40 min to 12 h). Results show that reheating reactivates the melt, which, through processes of chemical and thermal diffusion, reaches new equilibrium conditions. In all the experiments performed at T = 700-750 °C, a large number of crystal nuclei and spherulites grows in the groundmass, suggesting conditions of high undercooling. This process creates textural heterogeneities at the scale of few microns but only limited changes of groundmass composition, which remains clustered around that of the natural glasses. Reheating at T = 1,000-1,050 °C promotes massive groundmass crystallization, with a different mineral assemblage as a function of the redox conditions. Morphological modifications of clasts, from softening to sintering as temperature increases, occur under these conditions, accompanied by progressive smoothing of external surfaces, and a reduction in size and abundance of vesicles, until the complete obliteration of the pre-existing vesicularity. The transition from sintering to welding, characteristic of high temperature, is influenced by redox conditions. Experiments at T = 1,100-1,130 °C and under vacuum produce groundmass textures and glass compositions similar to that of the respective starting material. Collapse and welding of the clasts cause significant densification of the whole charge. At the same temperature, but in presence of air, experimental products at least result sintered and show holocrystalline groundmass. In all experiments, sublimates grow on the external surfaces of the clasts or form a lining on the bubble walls. Their shape and composition is a function of temperature and fO2 and the abundance of sublimates shows a peak at 1,000 °C. The identification of the features recorded by pyroclasts during complex heating-cooling cycles allows reconstructing the complete clasts history before their final emplacement, during weakly explosive volcanic activity. This has a strong implication on the characterization of primary juvenile material and on the interpretation of eruption dynamics.

D'Oriano, C.; Pompilio, M.; Bertagnini, A.; Cioni, R.; Pichavant, M.

2013-05-01

465

Recovery Act: Waste Energy Project at AK Steel Corporation Middletown  

SciTech Connect

In 2008, Air Products and Chemicals, Inc. (“Air Products”) began development of a project to beneficially utilize waste blast furnace “topgas” generated in the course of the iron-making process at AK Steel Corporation’s Middletown, Ohio works. In early 2010, Air Products was awarded DOE Assistance Agreement DE-EE002736 to further develop and build the combined-cycle power generation facility. In June 2012, Air Products and AK Steel Corporation terminated work when it was determined that the project would not be economically viable at that time nor in the foreseeable future. The project would have achieved the FOA-0000044 Statement of Project Objectives by demonstrating, at a commercial scale, the technology to capture, treat, and convert blast furnace topgas into electric power and thermal energy.

Joyce, Jeffrey

2012-06-30

466

Method of operating a centrifugal plasma arc furnace  

DOEpatents

A centrifugal plasma arc furnace is used to vitrify contaminated soils and other waste materials. An assessment of the characteristics of the waste is performed prior to introducing the waste into the furnace. Based on the assessment, a predetermined amount of iron is added to each batch of waste. The waste is melted in an oxidizing atmosphere into a slag. The added iron is oxidized into Fe.sub.3 O.sub.4. Time of exposure to oxygen is controlled so that the iron does not oxidize into Fe.sub.2 O.sub.3. Slag in the furnace remains relatively non-viscous and consequently it pours out of the furnace readily. Cooled and solidified slag produced by the furnace is very resistant to groundwater leaching. The slag can be safely buried in the earth without fear of contaminating groundwater.

Kujawa, Stephan T. (Butte, MT); Battleson, Daniel M. (Butte, MT); Rademacher, Jr., Edward L. (Butte, MT); Cashell, Patrick V. (Butte, MT); Filius, Krag D. (Butte, MT); Flannery, Philip A. (Ramsey, MT); Whitworth, Clarence G. (Butte, MT)

1998-01-01

467

28. RW Sugar Mill: 18761889. Boilingrange Furnace and Clarifier position. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

28. RW Sugar Mill: 1876-1889. Boiling-range Furnace and Clarifier position. View: In the boiling range all of the clarification, evaporation, and concentration of cane juice took place in open pans over the Continuous flue leading from this furnace. The furnace door through the exterior wall is at the end of the furnace. In the original installation, two copper clarifiers, manufactured by John Nott & Co. occupied this space directly above the furnace. In the clarifiers, lime was added to the cane juice so that impurities would coagulate into a scum on top of the near-boiling juice. The clarifiers have been removed since the closing of the mill. - R. W. Meyer Sugar Mill, State Route 47, Kualapuu, Maui County, HI

468

29. RW Meyer Sugar Mill: 18761889. Boilingrange furnace and clarifier ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

29. RW Meyer Sugar Mill: 1876-1889. Boiling-range furnace and clarifier position. View: In the boiling range all of the concentration, evaporation, and concentration of cane juice took place in open pans over the continous flue leaving this furnace. The furnace door through the exterior wall is at the end of the furnace. In the original installation two copper clarifiers, manufactured by John Nott & Co. occupied this space directly above the furnace. In the clarifier lime was added to the cane juice so that impurities would coagulate into a scum on top of the near-boiling juice. The clarifiers have been removed since the closing of the mill. - R. W. Meyer Sugar Mill, State Route 47, Kualapuu, Maui County, HI

469

Method of operating a centrifugal plasma arc furnace  

DOEpatents

A centrifugal plasma arc furnace is used to vitrify contaminated soils and other waste materials. An assessment of the characteristics of the waste is performed prior to introducing the waste into the furnace. Based on the assessment, a predetermined amount of iron is added to each batch of waste. The waste is melted in an oxidizing atmosphere into a slag. The added iron is oxidized into Fe{sub 3}O{sub 4}. Time of exposure to oxygen is controlled so that the iron does not oxidize into Fe{sub 2}O{sub 3}. Slag in the furnace remains relatively non-viscous and consequently it pours out of the furnace readily. Cooled and solidified slag produced by the furnace is very resistant to groundwater leaching. The slag can be safely buried in the earth without fear of contaminating groundwater. 3 figs.

Kujawa, S.T.; Battleson, D.M.; Rademacher, E.L. Jr.; Cashell, P.V.; Filius, K.D.; Flannery, P.A.; Whitworth, C.G.

1998-03-24

470

Programmable multi-zone furnace for microgravity research  

NASA Technical Reports Server (NTRS)

In order to provide new furnace technology to accommodate microgravity research studies and commercial applications in material processes, research has been initiated on the development of the Programmable-Multi-zone Furnace (PMZF). The PMZF is described as a multi-user materials processing furnace facility that is composed of thirty or more heater elements in series on a muffle tube or in a stacked ring-type configuration and independently controlled by a computer. One of the aims of the PMZF project is to allow furnace thermal gradient profiles to be reconfigured without physical modification of the hardware by creating the capability of reconfiguring thermal profiles in response to investigators' requests. The future location of the PMZF facility is discussed; the preliminary science survey results and preliminary conceptual designs for the PMZF are presented; and a review of multi-zone furnace technology is given.

Rosenthal, Bruce N.; Krolikowski, Cathryn R.

1991-01-01

471

40 CFR 458.10 - Applicability; description of the carbon black furnace process subcategory.  

Code of Federal Regulations, 2014 CFR

...false Applicability; description of the carbon black furnace process subcategory. 458...EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Furnace Process Subcategory §...

2014-07-01

472

Microstructure and mechanical properties of microwave sintered austenitic stainless steel  

Microsoft Academic Search

The objective of this work is focused on understanding the effect of microwave heating on sintering of 316L powders. The stainless\\u000a steel samples were prepared from prealloyed powders of 316L. The powder samples were compacted at a pressure of 560 MPa and\\u000a sintered at 1300°C in a microwave furnace of 2.4 GHz and 2KW capacity in nitrogen atmosphere. The sintering

S. Kennedy; S. Kumaran; T. Srinivasa Rao

2011-01-01

473

The impact of energy prices on technology choice in the United States steel industry  

SciTech Connect

In the last thirty years US steel producers have replaced their aging open hearth steel furnaces with basic oxygen or large electric arc furnaces. This choice of technology leads to the opportunity to substitute electricity for fossil fuels as a heat source. We extend earlier research to investigate whether or not energy prices affect this type of technology adoption as predicted by economic theory. The econometric model uses the seemingly unrelated Tobit'' method to capture the effects of the industry's experience with both technologies, technical change, and potential cost reductions, as well as energy prices, on adoption. When we include the prices of electricity and coking coal as explanatory variables, the four energy price coefficients have the signs predicted by the law of demand. The two price coefficients have a statistically significant effect on adoption of basic oxygen furnaces. The inclusion of energy prices leads to significantly more efficient estimates of other coefficients in the model. 19 refs., 3 tabs.

Karlson, S.H. (Northern Illinois Univ., De Kalb, IL (United States). Dept. of Economics); Boyd, G. (Argonne National Lab., IL (United States))

1991-01-01

474

Reheating during Hierarchical Clustering in the Universe Dominated by the Cold Dark Matter  

E-print Network

We investigate reheating of the universe by early formation of stars and quasars in the hierarchical clustering scheme of cold dark matter scenario, with perturbation fluctuations normalized by the COBE data. It is found that ionizing uv flux from OB stars with the abundance given by the standard initial mass function is strong enough to ionize the universe from $z\\approx 30$ to the present epoch, if 1--2\\% of the collapsed baryons go into stars. This lessens significantly the CMB anisotropies at a small angular scale. Reionization also increases the Jeans mass to $M_{\\rm luminous}\\approx 10^9M_\\odot$ for $z\\lsim 10$, which leads to a cut-off of the luminosity function of normal galaxies on a faint side. A strong uv flux is expected at $z\\approx 2-5$, and the null result of the Gunn-Peterson test is naturally explained. Early star formation also results in production of heavy elements, and the observational metal abundance sets a strong constraint on the photon energy injection into the intergalactic space.

M. Fukugita; M. Kawasaki

1993-09-25

475

Reheated Palm Oil Consumption and Risk of Atherosclerosis: Evidence at Ultrastructural Level  

PubMed Central

Background. Palm oil is commonly consumed in Asia. Repeatedly heating the oil is very common during food processing. Aim. This study is aimed to report on the risk of atherosclerosis due to the reheated oil consumption. Material and Methods. Twenty four male Sprague Dawley rats were divided into control, fresh-oil, 5 times heated-oil and 10 times heated-oil feeding groups. Heated palm oil was prepared by frying sweet potato at 180°C for 10 minutes. The ground standard rat chows were fortified with the heated oils and fed it to the rats for six months. Results. Tunica intima thickness in aorta was significantly increased in 10 times heated-oil feeding group (P < 0.05), revealing a huge atherosclerotic plaque with central necrosis projecting into the vessel lumen. Repeatedly heated oil feeding groups also revealed atherosclerotic changes including mononuclear cells infiltration, thickened subendothelial layer, disrupted internal elastic lamina and smooth muscle cells fragmentation in tunica media of the aorta. Conclusion. The usage of repeated heated oil is the predisposing factor of atherosclerosis leading to cardiovascular diseases. It is advisable to avoid the consumption of repeatedly heated palm oil. PMID:23320039

Xian, Tan Kai; Omar, Noor Azzizah; Ying, Low Wen; Hamzah, Aniza; Raj, Santhana; Jaarin, Kamsiah; Othman, Faizah; Hussan, Farida

2012-01-01

476

Development of Al-killed/Ti stabilized steels  

NASA Astrophysics Data System (ADS)

Several Al-killed/Ti-stabilized low carbon steels were developed in a Mexican steel industry with the aim of obtaining an interstitial free steel for automotive applications. The steelmaking route involved the use of 100% sponge iron which was feed into an electric arc furnace, vacuum degassed, ladle treated and continuously casted. The resulting slabs were then hot rolled at 1100 °C and coiled at 650 °C. Then, the steel plates were cold rolled at room temperature and sheets annealed at 700 °C. As-cast micro structure showed the presence of ?-ferrite with titanium nitrides in matrix and grain boundaries while in the ashot rolled condition, elongated grains showed the presence of titanium nitrides, titanium sulfides and titanium carbosulfides. The annealed sheets showed, additionally to the other precipitates, the presence of titanium carbides. Microstructure, texture, the Lankford ratio and mechanical properties of fully recrystallized coils fulfilled the target properties established by the automobile industry.

Ramirez-Ledesma, A. L.; Aguilar-Mendez, M. A.; Rodriguez-Diaz, R. A.; >G Aramburo,

2015-01-01

477

Partial transient liquid phase diffusion bonding of Zircaloy4 to stabilized austenitic stainless steel 321  

Microsoft Academic Search

An innovative method was applied for bonding Zircaloy-4 to stabilized austenitic stainless steel 321 using an active titanium interlayer. Specimens were joined by a partial transient liquid phase diffusion bonding method in a vacuum furnace at different temperatures under 1MPa dynamic pressure of contact. The influence of different bonding temperatures on the microstructure, microindentation hardness, joint strength and interlayer thickness

M. Mazar Atabaki; A. Talebi Hanzaei

2010-01-01

478

Steel slag affects pH and Si content of container substrates  

Technology Transfer Automated Retrieval System (TEKTRAN)

A substrate representing a typical greenhouse potting mix was prepared using 85% sphagnum peat and 15% perlite. The substrate was filled into 10 cm wide containers. A pulverized steel slag (SS) from a basic oxygen furnace, and dolomitic limestone (DL) were amended to the base substrate at a rate o...

479

On electrical load tracking scheduling for a steel Alain Hait1  

E-print Network

Decarburization (AOD), alloying and re- finement in Ladle Furnace (LF) and finally casting in a Continuous Casting the tasks. Finally, no idle time is allowed between two batches on the continuous casting machine. The main continuous time formulation that improves significantly the computation time. Keywords Steel plant, Mixed

Paris-Sud XI, Université de

480

Fibonacci lattices application for furnace processes control  

SciTech Connect

Universal structures formed during the fuel oxidizer and combustion mixing process are characterized by the Fibonacci gold ratio. This paper will demonstrate how the gold ratio can be used for control action in combustion. The combustion character in furnace apparatuses is in large part dependent on a reagent motion regime. In general, there are three such regimes: lamina (L), lamina-preturbulent or quasi-periodic (LPT) and turbulent-mixing (TM). Compound structures are absent from the L-regime and are characterized by a low Reynolds number Re. As Re increases the periodic regime remains consistent but one frequency process appears. The LPT and TM regimes are independent of material physical carriers and are characterized by the universal relationship of the oscillate frequencies, the so-called ``golden sections`` F*{sup n}, where F* is the gold ratio (F* = 1.618...) and n is the integer such that the degree of mixing is in proportion to n.

Khavkin, Y. [Univ. of Minnesota, Minneapolis, MN (United States). Dept. of Mechanical Engineering; Maktin, G.M. [A.O. NIVA, St. Petersburg (Russian Federation)

1995-12-31

481

Mercury in dumped blast furnace sludge  

NASA Astrophysics Data System (ADS)

Blast furnace sludge (BFS) is a waste generated in the production of pig iron and was dumped in sedimentation ponds. As these wastes often contain high contents of zinc, lead, cadmium, and arsenic, significant hazards to environmental surroundings may arise from former BFS sedimentation ponds. Sixty-five samples from seven BFS locations in Europe were investigated regarding the toxic element mercury (Hg) for the first time. The charge material of the blast furnace operations (coke, iron ores, and additives such as olivine, bauxite, ilmenite and gravels) revealed Hg contents from 0.015 to 0.093 mg kg-1. In comparison, the Hg content of BFS varied between 0.006 and 20.8 mg kg-1 with a median of 1.63 mg kg-1, which indicates enrichment with Hg. For one site with a larger sample set (n = 31), Hg showed a stronger correlation with the total non-calcareous carbon (C) including coke and graphite (r = 0.695; n = 31; p < 0.001). It can be assumed that these C-rich compounds are hosting phases for Hg. The solubility of Hg was rather low and did not exceed 0.43% of total Hg. The correlation between the total Hg concentration and total amount of NH4NO3-soluble Hg was relatively poor (r = 0.496; n = 27; p = 0.008) indicating varying hazard potentials of the different BFS. Consequently, BFS is a mercury-containing waste and dumped BFS should be regarded as potentially mercury-contaminated sites.

Földi, Corinna

2014-05-01

482

Description of a Furnace for the Creation of Anisotropic Porous Metals  

SciTech Connect

A furnace has been built for the purpose of producing anisotropic porous metals through solid-gas eutectic solidification. This process allows control of continuously formed anisotropic pores in metals and was discovered at the State Metallurgical Academic' University in Dnepropetrovsk Ukraine. The process incorporates hydrogen gas within the metal as it solidifies from the molten state. Metals which do not form hydrides, including iron, nickel, aluminum, copper and others can be formed in this manner. The furnace is housed within a ~.64 meter³ (30 ft³) ASME code stamped cylindrical stainless steel vacuum/pressure vessel. The vessel is a water chilled vertical cylinder with removable covers at the top and bottom. It can be evacuated to 20 mTorr or pressurized to 5.5 MPa (800 psi). A charge of 2700 cc (167 in³) of molten metal can be melted in a crucible in the upper portion within a watercooled 30 cm (12 in.) ID induction coil. A 175 kW Inductotherm power source energizes the coil. Vertical actuation of a ceramic stopper rod allows the molten metal to be tapped into a solidification mold beneath the melting crucible. The cylindrical mold rests on a water cooled copper base inducing directional solidification from the bottom. Mixtures of hydrogen and argon gases are introduced during the process. The system is remotely controlled and located in a structure with frangible walls specially designed for possible ambient pressure excursions as a result of equipment failure. This paper includes a general description of the furnace and operating procedure and a detailed description of the control, monitoring and interlock systems.

Gutsch, Thomas; Miszkiel, Mark; Schmale, David T.

1999-05-01

483

Waste Heat Recovery from High Temperature Off-Gases from Electric Arc Furnace  

SciTech Connect

This article presents a study and review of available waste heat in high temperature Electric Arc Furnace (EAF) off gases and heat recovery techniques/methods from these gases. It gives details of the quality and quantity of the sensible and chemical waste heat in typical EAF off gases, energy savings potential by recovering part of this heat, a comprehensive review of currently used waste heat recovery methods and potential for use of advanced designs to achieve a much higher level of heat recovery including scrap preheating, steam production and electric power generation. Based on our preliminary analysis, currently, for all electric arc furnaces used in the US steel industry, the energy savings potential is equivalent to approximately 31 trillion Btu per year or 32.7 peta Joules per year (approximately $182 million US dollars/year). This article describes the EAF off-gas enthalpy model developed at Oak Ridge National Laboratory (ORNL) to calculate available and recoverable heat energy for a given stream of exhaust gases coming out of one or multiple EAF furnaces. This Excel based model calculates sensible and chemical enthalpy of the EAF off-gases during tap to tap time accounting for variation in quantity and quality of off gases. The model can be used to estimate energy saved through scrap preheating and other possible uses such as steam generation and electric power generation using off gas waste heat. This article includes a review of the historical development of existing waste heat recovery methods, their operations, and advantages/limitations of these methods. This paper also describes a program to develop and test advanced concepts for scrap preheating, steam production and electricity generation through use of waste heat recovery from the chemical and sensible heat contained in the EAF off gases with addition of minimum amount of dilution or cooling air upstream of pollution control equipment such as bag houses.

Nimbalkar, Sachin U [ORNL; Thekdi, Arvind [E3M Inc; Keiser, James R [ORNL; Storey, John Morse [ORNL

2014-01-01

484

Characterization of Process Conditions in Industrial Stainless Steelmaking Electric Arc Furnace Using Optical Emission Spectrum Measurements  

NASA Astrophysics Data System (ADS)

Emission spectroscopy is a potential method for gaining information on electric arc furnace (EAF) process conditions. Previous studies published in literature on industrial EAF emission spectra have focused on a smaller scales and DC arc furnaces. In this study emission spectrum measurements were conducted for 140t AC stainless steelmaking EAF at Outokumpu Stainless Oy, Tornio Works, Finland. Four basic types of emission spectra were obtained during the EAF process cycle. The first one is obscured by scrap steel, the second is dominated by thermal radiation of the slag, the third is dominated by alkali peaks and sodium D-lines and the fourth is characterized by multiple atomic emission peaks. The atomic emission peaks were identified by comparing them to the NIST database for atomic emission lines and previous laboratory measurements on EAF slag emission spectra. The comparison shows that the optic emission of an arc is dominated by slag components. Plasma conditions were analyzed by deriving plasma temperature from optical emissions of Ca I lines. The analysis suggests that accurate information on plasma conditions can be gained from outer plasma having a plasma temperature below 7000 K (6727 °C).

Aula, Matti; Leppänen, Ahti; Roininen, Juha; Heikkinen, Eetu-Pekka; Vallo, Kimmo; Fabritius, Timo; Huttula, Marko

2014-06-01

485

Model of Draining of the Blast Furnace Hearth with an Impermeable Zone  

NASA Astrophysics Data System (ADS)

Due to demands of lower costs and higher productivity in the steel industry, the volume of operating blast furnaces has grown during the last decades. As the height is limited by the allowable pressure drop, the hearth diameter has grown considerably and, along with this, also draining-related problems. In this paper a mathematical model is developed for simulating the drainage in the case where an impermeable region exists in the blast furnace hearth. The model describes the quasi-stationary drainage process of a hearth with two operating tapholes, where the communication between the two pools of molten slag and iron can be controlled by parameterized expressions. The model also considers the case where the buoyancy of the liquids is sufficient for lifting the coke bed. The implications of different size of the liquid pools, communication between the pools, bed porosity, etc. are studied by simulation, and conclusions concerning their effect on the drainage behavior and evolution of the liquid levels in the hearth are drawn. The simulated liquid levels are finally demonstrated to give rise to a pressure profile acting on the hearth which agrees qualitatively with signals from strain gauges mounted in the hearth wall of an industrial ironmaking process.

Saxén, Henrik

2015-02-01

486

Model of Draining of the Blast Furnace Hearth with an Impermeable Zone  

NASA Astrophysics Data System (ADS)

Due to demands of lower costs and higher productivity in the steel industry, the volume of operating blast furnaces has grown during the last decades. As the height is limited by the allowable pressure drop, the hearth diameter has grown considerably and, along with this, also draining-related problems. In this paper a mathematical model is developed for simulating the drainage in the case where an impermeable region exists in the blast furnace hearth. The model describes the quasi-stationary drainage process of a hearth with two operating tapholes, where the communication between the two pools of molten slag and iron can be controlled by parameterized expressions. The model also considers the case where the buoyancy of the liquids is sufficient for lifting the coke bed. The implications of different size of the liquid pools, communication between the pools, bed porosity, etc. are studied by simulation, and conclusions concerning their effect on the drainage behavior and evolution of the liquid levels in the hearth are drawn. The simulated liquid levels are finally demonstrated to give rise to a pressure profile acting on the hearth which agrees qualitatively with signals from strain gauges mounted in the hearth wall of an industrial ironmaking process.

Saxén, Henrik

2014-08-01

487

A high-temperature furnace for applications in microgravity  

NASA Technical Reports Server (NTRS)

Technology in the area of material processing and crystal growth has been greatly furthered by research in microgravity environments. The role of efficient, lightweight furnaces with reliable performance is crucial in these experiments. A need exists for the development of a readily duplicated, high-temperature furnace satisfying stringent weight, volume, and power constraints. A furnace was designed and is referred to as the UAH SHIELD. Stringent physical and operating characteristics for the system were specified, including a maximum weight of 20 kg, a maximum power requirement of 60 W, and a volume of the furnace assembly, excluding the batteries, limited to half a Get-Away-Special canister. The UAH SHIELD furnace uses radiation shield and vacuum technology applied in the form of a series of concentric cylinders enclosed on either end with disks. Thermal testing of a furnace prototype was performed in addition to some thermal and structural analysis. Results indicate the need for spacing of the shields to accommodate the thermal expansion during furnace operation. In addition, a power dissipation of approximately 100 W and system weight of approximately 30 kg was found for the current design.

1991-01-01

488

Feasibility Study of Regenerative Burners in Aluminum Holding Furnaces  

NASA Astrophysics Data System (ADS)

Gas-fired aluminum holding reverberatory furnaces are currently considered to be the lowest efficiency fossil fuel system. A considerable volume of gas is consumed to hold the molten metal at temperature that is much lower than the flame temperature. This will lead to more effort and energy consumption to capture the excessive production of the CO2. The concern of this study is to investigate the feasibility of the regenerative-burners' furnaces to increase the furnace efficiency to reduce gas consumption per production and hence result in less CO2 production. Energy assessments for metal holding furnaces are considered at different operation conditions. Onsite measurements, supervisory control and data acquisition data, and thermodynamics analysis are performed to provide feasible information about the gas consumption and CO2 production as well as area of improvements. In this study, onsite measurements are used with thermodynamics modeling to assess a 130 MT rectangular furnace with two regenerative burners and one cold-air holding burner. The assessment showed that the regenerative burner furnaces are not profitable in saving energy, in addition to the negative impact on the furnace life. However, reducing the holding and door opening time would significantly increase the operation efficiency and hence gain the benefit of the regenerative technology.

Hassan, Mohamed I.; Al Kindi, Rashid