Lump Coal

The high lead slag from the smelting furnace is tapped continuously and transferred down a heated launder directly into the reduction furnace through a port in the side of the vessel. Lump coal for reduction is fed continuously to the furnace by conveyor and dropped direcdy into the bath. Heating for the endothermic reduction reactions is provided by oil injected down the lance. The combustion air stoichiometry is set at 95% of that required for complete oil combustion. Air is injected into the top of the furnace to afterbum the volatile materials from the coal and provide additional heat to the top of the furnace. Reduction temperatures range from 1170 to 1200°C to maintain slag duidity. 

Low Temperature Carbonization. The Lurgi Sptlgas process was developed to carbonize brown coal at relatively low temperatures to produce tars and oils (Fig. 5). A shaft furnace internally heated by process-derived fuel gas (Spblgas) is used. The product can range from a friable coke breeze to hard lump coal depending on the quality of the briquettes used in the feed. The briquettes, made in normal extmsion presses, break down into smaller sizes during carbonization. 

Low Temperature Carbonization. Lower temperature carbonization of lump coal at ca 700°C, primarily used for production of soHd smokeless fuel, gives a quantitatively and quaUtatively different yield of sofld, Hquid, and gaseous products than does the high temperature processes. 

The Lurgi fixed-bed gasifier operates using lump coal of a noncaking type with an ash composition chosen to avoid a sticky, partly fused ash in the reactor. A slagging version of this gasifier has been tested in Westfield, Scotland. Other fixed-bed gasifiers have similar coal requirements. 

Combustion of coal may take place in conventional fixed beds using lump coal and in which temperatures up to 1 300°C may be reached by entrained flow in which pulverised coal is injected into the combustion zone with the air, reaching temperatures up to 1 500°C or in the more recently developed systems of fluidised-bed combustion, again using pulverised coal but with... 

The nature or intimacy of contact of reactants can greatly affect the rate of reaction. Thus, finely divided coal bums much faster than lump coal. The titration of an acid with a base occurs much faster if the acid and base are stirred together than if the base is simply allowed to dribble into the acid solution. For a heterogeneous, catalytic reaction, the effect may show up in a more subtle way as the dependence of rate on the size of catalyst particle used. 

An explosive intended for use in coal mines must be safe to handle and to operate in the presence of material as ignitable as coal. Moreover to produce good lump coal slow-acting explosives should be employed which displace rather than fragment the coal. Conversely, in rock blasting greater explosive power is needed the safety factor is less important. 

Duobel. Trade mark of duPont Co for high-velocity, non-gelatinous permissible explosives furnished in two grades based upon velocity and cartridge count fair water resistance used for mining coal where lump coal is not a factor... 

DuPont s Permissibles, such as Duobel, Monobel, Lump Coal and Gelobei (Ref 6, pp43-6)... 

Birmingham Gas Company—lump coal from West Bromwich,. 

Kelt Width, Inches Lump Slone or Ore Gravel Lump Coal Crushed Ore and Stone t Slack Coal f Sand Wood Chips Grain... 

A few special low density expls in which there is some Na nitrate, have also been developed for producing lump coal... 

A2, B2, C2, D2, E2 F) EP-38, Lump Coal C2, Lump Coal CC2 and six brands of Monobel (Brands A2, AA2, B2, C2, D2 E2) also produces three brands of gelatinous expl Gelobel (brands A, A A C2) Hercules Powder Co, Wilmington, Delaware produces the following nongelatinous expls Bituminite D, Collier C, HP-47, HP-48 ... 

Experiments were carried out to determine the reduction of lump coal degradation due to the presence of coal fines (-16.0 mm) with the lumps at the different impact surfaces. Cushioning effects of fines consists of five different types of tests are as follows. 

The results of cushioning effects of both types of coal in Figs. 6 and 7 shows that the initial fines with lump coal does not reduce much fines generation when dropped on coal... 

R.K. Sahoo, D.M. Weedon, D. Roach, Coal degradation, Part-2 experimental study of several factors affecting Gladstone Port Authority s lump coal degradation, BSH 22 (5) (2002) 356-361. 

Width of belt Light or free-flowing materials, grains dry sand, etc. Moderately free-flowing sand, gravel, fine stone, etc. Lump coal, coarse stone, crushed ore Heavy sharp lumpy materials, heavy ores, lump coke ... 

Trimtex-Z Duobel A thru D Monobel AA, A thru E Lump Coal C, CC Gelobel AA, C... 

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