Waste to wealth: RCF experience

It is a universal truth that, the land and water resources are finite. Waste can be defined as something unwanted and having no economic value. In this ever-changing technical advancement, technology for waste utilisation is becoming the most important means of socio economic development. One must take inspiration from the ideal cycle of nature. The natural cycle does not produce any waste. The need of the hour is to find out an alternative to economically utilise the waste product.

 

The wastes generated are not only a loss to company, as these unwanted products consume the precious raw materials, but are also concern of damage to the environment. Thus, the reduction of these wastes is of prime concern for reduction of losses to the company as well serving for the betterment of the environment to the society at large.

 

Rashtriya Chemicals and Fertilizers Limited (RCF), which manufactures fertilisers (nitrogenous and complex) and various industrial chemicals, has adopted the principle in its true spirit and addresses the issue at its root cause itself.

 

Waste management

At the inception of a project, RCF ensures to use only eco-friendly technologies that produce less or negligible waste, conserve resources, and reuse treated effluents to the maximum possible extent. This is further followed up with upgradations from time to time, with the adoption of advancement of technologies, to improve energy efficiencies and make the plants more eco-friendly and competitive.

 

Waste to wealth

RCF has taken a step ahead in waste management and have taken various initiatives to not only reduce waste but to convert these wastes into wealth realisation potential for the company. A few of the prime examples of waste to wealth initiatives by RCF are as under:

 

Reduction in Greenhouse gases (GHGs) emission: RCF operates two nitric acid plants.  During the process of manufacture of nitric acid, nitrous oxide (N2O), an undesired product and one of the GHGs, is formed. This gas finds its way into the atmosphere through the stack along with other off gases. To address the release of this waste and harmful gas, RCF has installed a secondary catalyst in the reactors of nitric acid plants to destroy the N2O and convert it into harmless N2 and O2 gases. RCF implemented this project under the Clean Development Mechanism (CDM), a mechanism under Kyoto Protocol, resulting into generation of Certified Emission Reduction (CER) certificates. Under this mechanism, 1 CER is generated for 1 tonne of CO2 reduced. N2O, having a global warming potential of 310, relates to generation of 310 CERs per tonne of N2O reduced. Till date RCF has been issued 4,08,975 VERs (Voluntary Emission Reduction), which are emission reductions prior to registration of the project with UNFCCC, and 3,32,881 CERs.

 

Based on the operations of RCF, yearly 1 million CERs are expected to be generated from N2O abatement from the two nitric acid plants. At the prevalent rate of 2-3 Euro per CER in the market, these shall relate to generation of around Rs 20 crore per annum to RCF. Thus, the scheme of the reduction of unwanted hazardous waste N2O, in addition to benefitting the environment is also providing a source of revenue to RCF.

 

Value addition to phosphogypsum: RCF Trombay unit operates a 100 MTPD capacity phosphoric acid plant, which generates about 4.5 MT of phosphogypsum (a solid hazardous waste) as a by-product per every MT of phosphoric acid produced. To solve this problem, RCF has adopted Rapidwall technology for converting waste phosphogypsum into load bearing wall panels - a revolutionary, low-cost, prefabricated walling product with broad construction applications. 

 

Generation of pure water from municipal sewage: Industries need large quantities of water. In the past through various measures such as recycle and reuse of water by elaborate effluent treatment schemes, revamping of the plants for minimal water usage, deployment of state of the art technology like deep hydrolyser system in urea plant, reuse of steam condensate in various plants, etc, RCF has drastically reduced its water requirement. Besides, in 1999-2000, RCF set up a sewage treatment plant (STP) in Mumbai, which treats 5 million gallons (MG) of sewage to produce 3 MG of pure water. The reclaimed water of desired quality is stored in a 10,000 M3 open storage tank and pumped to various plants through a dedicated piping network. 
 

Buoyed by the success of this plant, RCF is planning to setup one more sewage treatment plant at Trombay having capacity of 3 MG per day (13,638 kilolitres/day).

 

Conclusion

Due to its systematic, dedicated and innovative approach towards reduction of waste, RCF Trombay, despite being located in the heart of the society, is able to meet the most stringent environmental regulations as compared to other fertiliser units. RCF has stood up to this challenge and has been managing its plants successfully for the last four and a half decade. The hard truth is that such challenges will surmount with more vigour and consequence in the days to come and RCF is well poised and committed to take on such challenges head on.

Waste to wealth tips: