SCIENCE AND INDUSTRY. 
Originally, coke was produced by the combustion of coal in limited supplies of 
air in stacks or piles, as in the process which is still used for the production 
of wood charcoal. The extraordinary wastefulness of such a procedure 
led to the first improvement—the coking of coal in beehive ovens in which 
the volatile distillation products were burned in the dome of the oven. The 
wastefulness in this process lies in—(a) the combustion of valuable products 
of distillation left in the coke oven gas, and (b) the loss of coke substance 
due to the simultaneous combustion of part of the coke first produced in the 
upper layers of the charge. The obvious development of withdrawing the 
gaseous products from the oven to be mixed with air for combustion on the 
outside of the oven was next introduced. There still remained, however, in 
this type of oven, the losses due to combustion of by-products and of more 
gas than was necessary for the maintenance of the carbonization process. 
The modern practice is to use ovens in which the gases, prior to combustion, 
are subjected to a system of by-product recovery whereby tar, ammonium 
sulphate, and benzol are removed from the gases, which are then burned 
around the oven and passed for waste heat utilization to the boiler plant. 
In Australia, up to about two years ago, the whole of the coke was made 
in beehive ovens. Recently a number of by-product recovery ovens have 
been installed, but the gases from these ovens are not “ stripped ” for benzol.. 
The question of the installation of up-to-date by-product recovery ovens is 
now receiving the attention of several large industrial enterprises in Australia. 
The New South Wales Government proposes to make the installation of 
by-product recovery ovens compulsory in the coke-making industry in that 
State. j 
Tt is probable that the quantity of coal used in the coking industry in 
Australia will reach 1,000,000 tons per‘annum in the near future, so that if all 
our coke ovens were equipped for the recovery of benzol, we might expect to 
obtain about 3,000,000 gallons of benzo! annually, that is about one-seventh 
of our total present petrol requirements. ye 
__ The third method—(c)—is the low-temperature process of carbonization, 
the primary objects of which are the production of a free-hurning smokeless 
solid fuel, suitable for purposes of domestic heating and steam generation, and 
a high yield of liquid fuels. Simultaneous solution of the smoke and air 
pollution problems, so far as domestic fuel consumption is concerned, would 
result from the successful production of such a fuel. 
3, LOW-TEMPERATURE CARBONIZATION. - 
For many years individual investigators have been experimenting on the 
carbonization of coal at temperatures much. below those used in the 
gas and coke-making industries. While there appears to be some 
difference of opinion among experts as to the immediate possibilities 
of low-temperature carbonization, in the existing state of knowledge, 
it is generally considered that a successful. commercial type of low- 
temperature carbonization plant has not yet been put into operation. 
Writing in 1918, A. B. Searle, in an Addendum to Professor B. V. Lewes’ 
book .on ‘“‘The Carbonization of Coal,” states that, unfortunately, the by- 
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