CEE Jul-Sep-2012

1. Introduction - Plastic waste generated from different cities and towns is a part of municipal solid waste (MSW). The management and disposal of waste polythene bags and other non-recyclable polythene I plastic wastes generated are a serious problem for our local bodies like municipalities and corporations. Littered Plastics waste being non-biodegradable gives an ugly appearance. . Disposal of plastic waste is causing many problems such as leaching impact on land and ground water, choking of drains and making land infertile. Indiscriminate burning of plastic causes environmental hazards . All plastics are polymers mostly containing carbon and hydrogen and few other elements like chlorine, nitrogen etc. It is estimated approximately 15,342 tons/day (TPD) of plastic waste is generated in the country and per capita generation of Plastic waste is approx. 5.7 Kg/annum. To overcome the above problem, VCW has taken an initiative to dispose plastic & Polythene waste for energy recovery in cement kiln thereby replacing fossil fuel to conserve the natural resources under the mega drive of Madhya Pradesh Pollution Control Board, Bhopal. 2. Co-processing of Plastic & Polythene waste in cement kilns has following environmental benefits - • High flame temperature of 2000 q::; , material temperatures up to 1450q::; and residence time of 4 - 5 seconds in oxygen rich atmosphere ensures complete destruction of waste. • High flame temperature ensures complete destruction of harmful pollutants. • Complete scrubbing of exhaust gas due to countercurrent flow of raw material– resulting in trapping of heavy metals, Sulphur and other pollutants within clinker. • No waste is generated that requires subsequent processing. Cement kiln operates under negative pressure or draft, thus preventing the generation of fugitive emission • With the large mass of clinker processed inside the cement kiln, there is a presence of a huge thermal inertia thereby eliminating the possibility of rapid swings in temperature. • Inclusion of ashes and residual metals from the wastes within the clinker crystal structure. • Kiln lines equipped with ESP/Bag filters– ensures negligible particulate emission . • Destruction and Removal Efficiency of greater than 99.9% 3. Co-processing of Plastic waste in Cement Kiln Our natural resources are getting scarce and alternate fuels such as plastics are an excellent way to alleviate this paucity of fossil fuels . This co-incineration of Plastic waste in Cement Kiln helps in recovery of energy & eco-friendly disposal of waste in an environment friendly manner. Vikram Cement Works has started using alternative fuel in its Cement Kiln from 2007 and conducted several trail run to find out the impact of gases on Environment and product quality. After successful trial run, VCW has started regular use of plastic & polythene from Sep.2008 under the guidance of M.P. Pollution Control Board. Vikram Cement Works has obtained regular permission for use of waste polythene bags I Waste pouches I other non recyclable waste polythene I plastic waste as a co -fuel in Cement Kiln. Vikram Cement Works has established network for collection of waste polythene from Municipal corporations like Indore, Ujjain, Nagda and Pithampur area. 4. System for shredding of Plastic waste We are getting different size of Plastic and Polythene waste that needs further shredding preferably below 20mm size to directly be fed in the precalciner. In view of this, we have installed Plastic & Polythene shredding machine for size reduction. This is a fully automated machine in which the trucks loaded with plastic waste can be direc~y unloaded in the hoppers. From the hoppers plastic waste is being transported through a small covered belt conveyor to the shredder, which shreds the plastic waste into very small pieces. After that, the shredded plastic waste is pneumatically conveyed to closed storage bunkers. From the storage bunkers, the plastic waste is being transported through covered conveyor belt of alternate fuel feeding system. 7