Fly ash,a major component of coal ash used in the various thermal power plants of the Rajasthan Rajya Vidyut Utpadan Nigam Ltd (RRVUNL) which was once a health hazard as the ash particles used to get lodged in the deepest part of the human lungs triggering asthma, inflammation and immunological reactions is now a money spinner.
The RRVUNL in the year 2016-17 earned Rs 131 crore from its sales to the cement manufacturers. The removal of the fly ash from the thermal plants sites has reduced the damage it was causing to the human living near the plant sites.
The RRVUNL’s production units Kota Super Thermal, Suratgarh super thermal unit, Ramgarh gas-thermal, Dholpur combined cycle unit, Chhabra super thermal unit and the Kalisindh thermal units combined produces 6543 MW of power consuming millions of tonnes of coal each year.
Once the Kota thermal power station’s waste fly ash was causing health problems for the entire city and neighbouring areas as there were no takers for this fly ash.
But in the past 10 years the use of the fly ash in cement and brick manufacturing has changed the scenario and the heaps of black fly ash has now become a revenue earner,.
According to AK Beniwal, the superintendent engineer of the Kota Super Thermal, the cement manufactures are lifting the heaps of fly ash for use in manufacturing cement.
Ash content of the coal used in various thermal power station ranges between 38-47 percent. The ash is collected in electrostatic precipitators which have an efficiency of 99.3 percent and 99.7 percent.
The main method of disposal of fly ash from the power stations is by mixing with water, the resultant slurry is pumped through pipes to ash disposal ponds. Fly ash adds longer life to the cement and the concrete structure. The massive Ghatghar dam and the world’s tallest building Burj Khalifa were built using fly ash mixed cement.
The fly ash market is growing day by day because of urbanisation in emerging economies and increasing constructional activities internationally. In compliance with Govt. of India Gazette Notification issued on 14th Sept. 1999, for making available ash free of cost , the various thermal power units KSTPS has achieved 100 percent dry fly ash utilisation. The various thermal power stations signed agreements for dedicated generating units allocations including construction & operation of complete dry fly ash evacuation system from each unit using silos. According to the agreement, these companies were allowed to set up the silos and take away the fly ash for free for five years. After this, the evacuation system would become the property of the RRVUNL.
The Kota Super Thermal Power station has arrangement with Associated Cement Co. Ltd,. Birla Cement Works Ltd. Grasim Industries Ltd.Mangalam Cement Ltd. Shree Cement Ltd,. These cement units pay Rs 125 to Rs 480 per tonne for the fly ash. Each unit consuming 1000 metric tonne of coal generates about 270 tonnes of fly ash per 1000 metric tonne. The pond ash is provided free of cost and has been utilised by various small entrepreneurs i.e. brick-kiln industries, small fly ash product industries, and for land filling by National Highway Authority of India.
