Distillieries - Environmental Clearance

Distilleriesd) CO 2 recovery plantThe CO 2 generated during the fermentation process can be collected, cleaned and storedbefore being used in the process. CO 2 is necessary for carbonation and to provide inertatmospheres as required by the process.e) Nitrogen generationBreweries may use nitrogen instead of CO 2 to provide inert atmospheres. Nitrogen can begenerated onsite from atmospheric air through a thermal or membrane separationtechnique or can be supplied in bulk from external sources.f) Electricity supplyMost breweries purchase electricity from the national grid, although some usecogeneration/combined heat and power (CHP) plants that produce both electricity andheat/steam.3.8 In Plant PracticesMaltingAs most of the maltries in India practice compartment malting in which manual handlingof material-in-process is necessary, good housekeeping assumes importance as so far asreduction of effluent volume and pollution load is concerned. Some of the process stepswhere common plant practices are responsible for large effluent volume and pollutionloads are enumerated here.SteepingAs three steep cycles are common most maltries, they have three conical steep vesselswith capacities ranging from 10-20 m 3 each fitted with false bottoms. Skimmings fromsteep vessels are normally thrown on to the floor and are washed into the drainperiodically during floor washing.GerminationManual transfer of grain from the germination box to another, causes loss of some of thegerminating grain. Once again these grain settle on the floor and are washed periodicallyinto the drain. At a subsequent stage, when rootlets are removed from the malted grain,the handling causes a lot of these rootlets to settle on the floor and find their way to thedrain in a similar manner. In general, the sewage in the open drains in maltries is rich insuspended solids and is the source of the odour nuisance.BrewingIn general, brewing is a clean-industry in India where handling of materials is done fairlysystematically and good house keeping practices are followed. However to the extent thatgood house keeping and in plant control of pollution are possible, the plant practices aredescribed below.After screening, the grain is conveyed by bucket elevators to the three-roll mill where drymilling is performed.TGM for Distillery Industry 3-32 August 2010