Simulation furnace

At temperatures in excess of 750°C the addition of water vapour accelerates the rate of growth of FeO (Fig. 7.10) by producing large pores in the FeO" . At much higher temperatures (1 200°C) Sheasby et have found that addition of steam to Oj-Nj, Oj-HjO-Nj and HjO-Nj, in a simulated reheating atmosphere furnace, caused increases in scale growth due to improved adhesion at the scale/metal interface. They concluded that water vapour enhances scale creep as previously reported by Tuck et... 

Fig. 7.13 Influence of coal chlorine content on the corrosion rates of low-alloy steels exposed to laboratory simulation of furnace wall corrosion (Brooks, C.E.G.B., private communication)...

FIGURE 42 Ancient smelting furnace. A simulated ancient smelting furnace used to replicate ancient metallurgical processes (a) plan (b) cross section. 

The FPL vertical wall furnace used in our study was described in some detail by Brenden and Chamberlain (6). This furnace is normally used to evaluate the fire endurance of wall assemblies. The basic guidelines for the furnace test method are given in the ASTM E-119 standard (5). The method was designed to evaluate the ability of a structure to withstand a standard fire exposure that simulates a fully developed fire. The furnace is gas fired, and its temperature is controlled to follow a standard time-temperature curve. A load may be applied to the assembly. The failure criterion can be taken as time at burnthrough, structural failure, or a specified temperature rise on the unexposed side of the wall—whichever comes first. The construction of the furnace is not specified in the ASTM E-119 standard. 

But that comes later. Next to the room where the bodies are burned is a large "reception hall," arranged so as to give the impression of the antechamber of a bathing establishment. It holds 2000 people, and apparently there is a similar waiting room on the floor below. From there on the upper floor a door and a few steps lead down into a very long and narrow gas chamber. The walls of this chamber are also camouflaged with a simulated entry "to shower rooms" to mislead the victims. The roof is fitted with three traps which can be hermetically closed from the outside. A track leads from the gas chamber towards the furnace room. 

The tests involved mixing known amounts of silver chloride with sodium hydroxide. The silver chloride was precipitated from a simulated anolyte solution with composition similar to that expected after the anolyte solution has been passed through the polishing circuit of the IRS. Metals in the simulated anolyte solution included Fe, Al, and Cu. The silver chloride/sodium hydroxide mixture was placed in a nickel crucible and then into a furnace heated to 600°C. After termination of the reaction, the crucible contents were quenched in water, washed out with water, and filtered. A silver mass balance was then performed. 

The pot furnace was constructed so that the radiant heat flux, which would prevail at the top of the fuel bed in a traveling grate stoker or incinerator, could be simulated under batch conditions. The burning rates could be determined by measuring the weight loss of the fuel bed as a function of time. The pot was constructed in two sections (Figure 1)- the overbed section (combustion system) and the fuel bed section (conversion system). Secondary air (overfire air) was supplied at a number of... 

The objective of Lamb et al s experimental work [4] was to obtain measurement data on burning rates (conversion rates) of a simulated crosscurrent moving bed. The experimental data would be applied to the combustion process in an inclined grate furnace. 

Lamb et al studied the conversion concept of a crosscurrent moving bed. The PBC system consisted of a trolley filled with a fuel bed of bagasse. The trolley rolled horizontally over a vertical air duct to simulate the moving bed (Figure 3). The speed of the trolley was controlled to keep the flame in a stationary position over the duct. An electrically heated platen, 30x15 cm, was placed horizontally 12 cm above the base of the bed, simulating radiation from furnace walls. 

They used a vertical cylindrical pot furnace of batch type, like Rogers. Two conversion concepts were simulated (a) overfired, updraft, fixed horizontal grate, and batch reactor and (b) underfired, updraft, fixed horizontal grate, and batch reactor. The diameter was 178 mm and primary air was supplied under the grate (Figure 7). A mirror was placed above the overbed section to be able to observe the combustion behaviour. 

The objectives of Aho s study [8] were to investigate the effects of peat type, particle density, diameter and moisture content, and oxygen concentration on the flue gas emissions of nitrogen oxides and sulphur dioxide from a homogenous countercurrent batch bed combustion using a pot furnace. His aim was to simulate the interaction of chemistry between the fuel bed system and the combustion chamber of a overfired batch bed. However, he also presented some results on the combustion heat rate. 

Dong W., Three-Dimensional Computer Simulation For Grate Combustion and NOx Emission with a New Air Supply Ecotube System, Licentiate Thesis, TRITA-TPM-65, at Division of Heat and Furnace Technology, Dept of Metallurgy, Royal Inst of Technology, Sweden (1998). 

Submodel for the Grate for Flow Simulations of Grate Fired Furnaces , presented at Swedish-Finnish Flame-day, 30 Sept, Vaxjo, Sweden, (1999)... 

Ford N., Cooke M.J., and Pettit M.D.,"The use of a laboratory fixed-grate furnace to simulate industrial stoker-fired plant", J. of the Institute of Energy 65, 137-143 (1992)... 

Figure 4.24 N and B coimplanted in 4H-SiC and annealed in an inductively heated furnace at 1,600°C for 10 minutes within a SiC crucible and high-purity Ar atmosphere, (a) Comparison between as-implanted and annealed N and B profiles, (b) Comparison between the N annealed and simulated profile these were computed under the hypothesis of an N FED diffusion. (From [91]. 2002 Material Science Forum. Reprinted with permission.)...

Nuclear waste glasses are complex mixtures of more than 30 elements, usually prepared by methods quite different than those used commercially to produce plate glass, for example. Canisters of glass (1-ft-dia x 6-ft-tall) have been prepared by direct furnace melting of a mixture of the waste oxides and an appropriate glass frit. The present experiment simulated this procedure on the laboratory scale. 

The melt used in this work was prepared from the residue of hydrogen-donor extraction of Colstrip coal with tetralin solvent in such a way as to simulate the composition of an actual spent melt. The extraction was conducted in the continuous bench-scale unit previously described (17) at 412°C and 50 min residence time. The residue used was the solvent-free underflow from continuous settling (17) of the extractor effluent. The residue was then precarbonized to 675°C in a muffle furnace. The melts were blended to simulate the composition of a spent melt from the direct hydrocracking of the Colstrip coal by blending together in a melt pot zinc chloride, zinc sulfide, and ammonium chloride, ammonia, and the carbonized residue in appropriate proportions. Analysis of the feed melt used in this work is given in Table I. 

Fig. 10.15 Simulated temperature distribution at the electrolyte during an operation of the singlecell stack model. The stack is assumed to be operated at 1000°C in an electric furnace.

Figure 24 The seesaw phenomenon by instantaneous solids distribution in the boiler at simulation time of (a) No. 28.9 s and (b) No. 38.7s. The red circles indicate high solids volume fraction on the top wall of the furnace (Zhang et al., 2010).

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