Recovery and Recycling of Liquid Effluent at GNFC – A Step towards Zero Effluent

Abstract

The Gujarat Narmada Valley Fertilizers Company Ltd (GNFC), a giant fertilizers and chemicals complex, owns the world's largest single stream ammonia and urea plants, and is located in the predominantly backward area of Bharuch District in Gujarat State, India. The company began commercial production on 1st July 1982. GNFC's performance as regards both capacity utilization and pollution control, has been good right from commissioning. Concerning pollution control, the company has adopted a productivity oriented approach which is entirely different from the usual ‘policeman' approach or ‘problem' approach. The company decided to find applications for each of the pollutants. Regarding liquid effluents, the company has successfully concluded a number of research and development projects as a result of which nearly 71% of the total volume of liquid effluent is put to productive use. This has helped the company to reduce the fresh water intake by about 18,000 m3/day (much more than the total volume of fresh water required by the whole of Bharuch city!). The remaining volume (29%) leaving GNFC premises completely conforms to irrigation standards and has been utilized by farmers for the last 5 years. This has resulted in a ‘mini green revolution' in the water-scarce area of Bharuch District. Since the entire effluent is either being recycled within the company or being used by farmers, the company has reached a stage of ‘zero effluent'. The company has also saved more than US$ 500,000 to date, by properly managing liquid effluent.