Sugar Industry, in terms of investment, turnover, employees and farmers is the second largest agro-based industrial activity in Pakistan after textile. National sugar scenario clearly suggests that techno-economic aspects of its processing need to be considered from its overall efficiency and energy management stand point.
This proposal is confined to energy management by considering each sugar mill as power plant by burning smokeless coal releasing bagasse for the production of writing paper.
There are 74 sugar mills, releasing about 15 million tonnes of bagasse used chiefly for burning in the boilers for producing steam for power generation to meet the electricity requirements of the mills.
Extra electricity over and above their requirement is sold to WAPDA by a few mills. More than one million tonnes (conversion factor 5.46 tonnes of bagasse produces one tonne of paper) of writing paper with 15-20 percent of imported or locally produced eucalyptus wood pulp can be produced with well established Chinese Technology.
This proposition is possible if alternative fuel at competitive rates is made available to sugar mills. In 1989, JICA of Japan submitted a feasibility report concluding that smokeless coal, based on Lakhra, Sindh Coal fields is technically and commercially viable that can substitute kerosene oil, fire wood and furnace oil. It has been estimated that sugar mills based on local coal would need 1.5 to 1.6 million tonnes per annum.
The requirement of slaked lime needed for making it smokeless is 60 to 70 thousand tonnes per annum. Slaked lime can be produced from the inexhaustible limestone resources of Sindh. Needless to say, if we adopt this proposition, the following benefits are expected:
Sugar mills would produce electricity by burning locally available smokeless coal throughout the year for their consumption and selling to WAPDA or supplying it to the rural areas for setting up small and medium industries.
This proposition will improve the profitability of sugar operators as their capital return will be quick, reduce and stabilise sugar prices, release bagasse for the production of writing papers presently imported and create job opportunities in backward mining areas where coal and limestone are located and in rural areas where sugar mills are operating.
This proposal is particularly important in the context of balance of payment problem because a large sum of foreign exchange is spent on the import of furnace oil and writing paper.
Based on above, a proper study need to be initiated regarding techno-economic analysis of sugar mill(s) from energy management standpoint ie, use of smokeless coal releasing bagasse for the manufacturing of writing paper, flue gases of lime-kiln or boilers may be used as an input for making gypsum plaster (120o to 150oC is required).
Gypsum plaster so obtained will be cheaper than cement for building construction industry as practised all over the world. As it is an import substitution proposition, it appears appropriate, that the study may be initiated by Trade Development Authority (TDA), Ministry of Commerce to minimise import of energy materials and writing paper and Smeda, Ministry of Industries, Production and Special Initiatives for creating medium to small scale industries around the operating sugar mills villages.
(The author is working as a Mineral Sector Specialist with Planning Commission, Government of Pakistan, Islamabad. E-mail:engineersplanners@yahoo.com)