Pot furnaces

At red heat, a low carbon ferrous metal, in contact with carbonaceous material such as charcoal, absorbed carbon that, up to the saturation point of about 1.70%, varied in amount according to the time the metal was in contact with the carbon and the temperature at which the process was conducted. A type of muffle furnace or pot furnace was used and the kon and charcoal were packed in alternate layers. 

Reverberatory and blast furnaces Pot furnaces Reverberatory furnaces Blast and electric furnaces Basic O2 and electric arc furnaces Dust-handling equipment Sludge incineration Dryer... 

Gefass-kunde, /. ceramic art. -ofen, m. (furnace containing receptacles), retort furnace, crucible furnace, pot furnace, etc. gefasst, p.p. p.a. see fassen. 

Hafen, m. pot harbor, port, -ofen, m. Glass) pot furnace. 

Kessel-niederscUag, m. deposit in a kettle, boiler or reservoir, -ofen, m. pot furnace crucible furnace. -rohr, n. boiler tube, -spaonung,/. boiler pressure, -speisewasser, n. boiler feed water, -speisimg, /. boiler feeding, boiler feed. 

Spray-aluminised coatings are used for exhaust valves in automobile engines, exhaust and silencer systems (double and triple life), tyre moulds, gas ducting, heat-treatment pots, furnace ladles, carburising boxes and fans handling hot gases. Similar applications utilise Calorised and hot-dip aluminised coatings. Hot-dip aluminised steel wire has been used in steel-cored aluminium conductors for overhead transmission lines. For some... 

An aluminum scrap fire developed near a melting furnace. Fire departments responded and sprayed water on the flames. Suddenly the pot furnace exploded. It is presumed that water from the fire hoses entered the furnace which contained about 900 kg of molten aluminum... 

Rogers experimental work [2] deals with the combustion of a fuel bed in a batch reactor (pot furnace). Rogers primary objective was to study the effect of the primary air rates (underfire air) on the burning and ignition rates of wood fuel. 

Figure 1 Rogers pot furnace is divided into A- the bed section andB-overfire section. [2]...

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... 

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. 

Figure 7 A schematic illustration over Stubington et als pot furnace and analysing system. [6]...

The experiments were carried out in the commonly used cylindrical vertical pot furnace (Figure 8). The conversion concept was overfired, updraft, fixed horizontal grate, and batch reactor. The furnace dimensions were 250 mm i.d. and 300 mm in height. The furnace was constructed in two sections, here called conversion system and combustion chamber. This was one simple solution to be able to weigh the mass loss of the packed bed. 

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. 

Gort applied a typical pot reactor with vertical cylindrical shape. The conversion concept of Gort s conversion reactor was updraft, over-fired, fixed horizontal grate, and batch reactor. The reactor casing had a inner diameter of 0.3 m and a height of 0.8 m. The design of Gort s pot furnace is very similar to Koistinen et al s. 

Batch combustion of refined wood fuels, so-called wood pellets in a wood stove or pot furnace is a practical example of a homogeneous batch conversion system. 

Batch conversion systems hotnog fixed batch bed cocurr homog moving bed crosscurr homog moving bed fixed grate system overfired pellets in a stove or a pot furnace, see Figure 33. 

Cold-seal stellite bombs and high oxygen pressures were used as described previously (6, 7, 8, 9, 10). An ordinary pot furnace was used for heat treatments carried out in air. As starting materials, purified palladium black (Fisher Scientific Co.) was mixed intimately with the other oxides or hydroxides [PbO, Sr(OH)2 8H20, CaO, CdO, Mg(OH)2]. The mixtures generally were inserted into gold foils and heat treated under various conditions of temperature and oxygen pressure. The runs were quenched and the products examined by x-ray diffraction. 

The thermal efficiency of glass melting furnaces is relatively low, in particular that of pot furnaces. Values of 20—35% are reported for tank furnaces with classical heating (see below). Efforts to raise thermal efficiency led to experiments with shaft and rotary furnaces, with fluidized bed melting furnaces, etc. Only electric boosting and all electric glass furnaces have so far found wider practical application. 

Crystal glasses were traditionally melted in pot furnaces, but nowadays small continuous tank furnaces are used. Lead glasses are conveniently melted in Unit-Melter furnaces, lead-free glasses in all-electric furnaces with a daily output of several tons (cf. Fig. 102). Machine forming is being gradually introduced even for these types of glass. 

The actual heat consumption is several times higher than the above theoretical values, as a result of heat losses. The thermal efficiency of glass tanks heated with gaseous or liquid fuels is then in the range of 20 — 35%, that of all-electric furnaces amounts to 60—80% (not taking into account the efficiency of electric power generation). In the case of pot furnaces the thermal effiency is very low, about 10% or less. 

The reaction is carried out in pot furnaces (low brick-lined hearths with lids), continuous furnaces or rotary plate furnaces. The melt produced in the furnace is mashed with water, the undissolved material removed and the solution concentrated to 60 to 62% sodium sulfide by evaporation in cast iron vessels. This concentrated solution solidifies at ca. 90°C. 

---