Central Pollution Control Board (Ministry of Environment & Forests, Govt. of India) Parivesh Bhawan East Arjun Nagar, Delhi
Co-processing of wastes in cement kiln is emerging as one of the environment friendly alternative disposal method in the recent years. Distillery spent wash has high organic content and dissolved inorganic solids which require careful handling and proper disposal to avoid damage to the environment. Presently it is being used on to land to provide nutrient value, though it contaminates both the ground water and surface water sources, as most often it is practiced in non-scientific manner. The adverse effect of spent wash disposal, via bio-composting is magnified during the rainy season. Concentration of spent wash in multiple effect evaporators and its subsequent incineration is also being practiced. However, it is not found technically and economically feasible in majority of cases. Hence, Central Pollution Control Board (CPCB) proposed, co-processing of concentrated spent wash in cement kiln. There are around 400 distillery units in India, with a total production capacity of about 3800 million litres of alcohol. Average generation of spent wash is around 812 litres / litre of alcohol produced, depending on continuous or batch process and quality of molasses used etc. Thus the co-processing of spent wash concentrate in cement kiln has following benefits: (a) wastes are destroyed at a higher temperature of around 1200-1400 C and longer residence time, (b) inorganic content gets fixed with the clinker apart from using the energy content of the wastes leaving no residue behind (c) the acidic gases, if any generated during co-processing gets neutralized, since the raw material in cement kiln is alkaline in nature, and (d) such phenomenon also reduces resource requirement. While in case of incineration, residuals require to be disposed suitably. A typical physico-chemical characteristics of distillery spent wash is depicted at Annexure- I. The production of cement in India is about 200 Million Tonnes per annum. The country, therefore, has potential to utilize spent wash concentrate from the distilleries for co-processing in cement industry. Based on satisfactory performance of trial run, CPCB has granted regular permission for Co-processing of few categories of wastes and 25 cement 0
manufacturing units in various States have already started co-processing of permitted wastes. Further, trial studies are undertaken for various other wastes.
Despite of co-processing having inherent advantages, a careful & scientific study of trial run for spent wash with potential to damage environment during transportation, handling, storage and processing was done. The desired handling, transport and storage applicable to distillery spent wash have been described in the following sub-sections. Distillery spent wash is not categorized as a hazardous waste, still co- processing of the same needs to be handled in an environmentally sound manner, avoiding the possibilities of environment contamination. These guidelines includes standard methodology for submission of application for streamlining the entire processing mechanism taking all essential safeguards along with the delivery of approvals in a reasonable time frame.
Occupiers responsibility for handling of spent wash
“Occupier” in relation to any factory or premises, means a person who has, control over the affairs of the factory or the premises and includes in relation to spent wash; The occupier shall take all adequate steps while handling spent wash to: (a) (b) Contain contaminants and prevent leakages/spillages and limit their consequences on the environment; and Provide persons working on the site with the training, equipment and necessary information.
The concerned distillery shall obtain...