(228d) Biorefinery BASED ON Indian Distillery

A.K.Ray* and Prodosh Sanyal** 

*Indian Institute of Technology Roorkee, Saharanpur,India

** National sugar Institute, Kalyanpur, Kanpur, India

Distillery in India principally produces industrial alcohol/ rectified spirit. Alcohol is used  not only portable purposes , but also is a renewable source of energy required primarily in IC engines,a supplier of energy through efficient fuel cell  construction and power alcohol for substitute of gasoline. This can also be employed for production of a number of chemicals. Some of the chemicals manufactured in india are: ethylene based- such as ethylene-diamine,PVC, polystyrene,ethylene oxide/glycol, polyethylene and acetaldehyde based, namely butadiene, PV acetate, acetic acid, acetic anhydride,ethyl, butyl  and other acetates, vinyl acetate monomer,pyridine,2-ethyl hexanol,n-butanol,monochloroacetic acid , propionic acid etc.In this paper the status of some of the above chemicals in regards to their installed capacities , demand and market  potential are discussed.

Ethanol is usually produced  by fermentation of molasses( generally 5% on cane)   with an yield, 250.7 liter per kg of molasses with yeast Saccharomyces Cerevisiae or by strains, Zymomonas mobilis. Use of cane juice, jaggerry, mohua flower are also used in some inatallations. An alternative feedstock for ethanol production is ligno-cellulosic biomass;bagasse ,rice straw,cotton straw,groundnut  shells,wood and forest residues, waste paper products, paper and pulp mill wastes using thermophillic anerobic bacteria, clostridium thermocellum. Cellulose enzyme produced by aerobic mesophilic fungus, Trichoderma reesei, also releases glucose from  plant biomass  and converts to ethanol  by simultaneous saccharification and  fermentation.

Acid hydrolysate of hemicelluloses extracted from bagasse and other agriculture wastes by fermentation with the yeast Saccharomyces cerevisiae has also been a potential feedstock..

Starch based natural produce like wheat, rice, millets,potatoes,corn,tapioca can also be a potential and economic source of ethanol production. In this paper potential for profitable production of alcohol by various sources are reviewed.

Economics of alcohol manufacture depends strongly on the economy of steam consumption as it contributes a significant fraction (40%) of the total cost. Most of the Indian distilleries produce alcohol with 1.5-2 times ( of the order of 2.5 kg/kg of alcohol production) higher steam consumption than the actually required. Attempts have been made to highlight how production can be improved by various means with lower consumption of energy and the factors influencing it. The absolute alcohol is manufactured from rectified spirit, by various means such as azeotropic and extractive distillation, using dehydrant, molecular sieves or by membrane separation. The status regarding the production of power alcohol  and as gasoline substitute as well as chemicals in Indian distilleries is introduced.

Spent wash and spent lees ,the two liquid waste streams can also be employed for manufacture of  chemicals and energy, especially biogas. Performances of installations for handling distillery spent wash using downflow stationary fixed film type anaerobic filter  and other designs  in Indian distilleries are reviewed.