Abstract

                                In the manufacture of activated carbon from paddy husk, as carried on at present, the ignition of the first char at high temperature is done in thick iron tubes about 4 ft. in length and 8 in. in diameter. These tubes, to make them fairly airtight, have to be provided with lids hinged to both ends. Such iron pipes at the present market rate will cost anything from Rs. 30 to Rs. 40 each and even at that high cost are not easily obtainable. As these iron pipes have to be subjected to very high temperature, each time a charge of carbon is ignited they get fire-eaten after 50 to 60 charges and have therefore, to be discarded, and new ones substituted. And for the ignition of carbon in such tubes under high temper ture it is also necessary to build elaborate and costly furnaces with brick ir-mud with the provision of iron gratings, ash pit, etc. To build a furnace of the kind designed by the Government Agricultural Chemist to take in three iron tubes of the dimensions mentioned above, it costs roughly Rs. 130. Because of such high cost and intricacy of building such furnaces, it is not possible for the majority of cane growers to prepare their own carbon to clarify their cane juice.

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