Distillieries - Environmental Clearance

tray construction and heated by steam through re-boiler located at the bottom ofcolumn.The alcohol from rectifier column is then taken to product cooler to cool it down to350 C. The Impure cut from the top of the Degassifying section is taken to degasscondenser & condensed against water. The condensate is then fed to heads / aldehydecolumn where it is diluted with water for further rectification in the column & finallythe impure cut is removed from the top vent condensers of the heads column.1.3 Falling film spent wash evaporator1.3.1 Process Description1.3.1.1 Effect Evaporator using vapour from Analyser columnFeed Inlet – E1 – E2 – E3 –OutletSince the evaporator is integrated with distillery plant, vapour from Analyser columnis used as heating media in evaporator. As a result, the temperature profile inevaporator is lower. Outlet Product Concetration is also lower, just about 38.16%.This will considerably reduce the offline CIP frequency and so the downtime ofevaporator.1.3.1.2 Process description for tubular evaporatorWe propose a 3 effect evaporator system for the spent wash designed forconcentration from 19.4 % to 38.16 %. All the Effects are falling film type withvapour separators. The feed will be introduced in Effect 1. Subsequently it will betransferred to Effect 2 and then to Effect 3 & finally to battery limit, by means oftransfer cum recycle pumps. Final concentration is achieved in E3. Level controlloops are provided for all effects to ensure trouble free operation. The vapours fromAnalyser column are used as heating media in E1 and recovered in the form ofcondensate. Vapours separated in Effect 1 are used as heating media in Effect 2.Similarly vapour generated in Effect 2 are used as heating medium in Effect 3.Finally the vapours separated in VS3 are condensed in a surface condenser. Thecondensate from all the effects and condenser shall be pumped out by condensatepumps.1.4 Spent wash generation with integrated mode of operationThe generation of spent wash with various combinations of sugars in molasses willhave a overall impact on operation of the plant & generation of spent wash. The chartof spent wash generation is enclosed herewith for the reference. The assumptionbasis is that the generation of spent wash is limited to about 4 Litres / Litre of alcoholproduced at the maximum. In case of Fermentable sugars ranging between 42 to 48%w/w, the usage of evaporation plant is a must to restrict the generation of the spentwash below 4 litres / litre of alcohol produced.As the fermentable sugars concentration increases in molasses or in case of the use ofB Heavy or B1 Heavy molasses, the F / NF ratio is much better which allows to takeiii