Fly Ash Applications in Agriculture and Forestry
Years ago, when Dehradun was still part of UP and the power position was erratic to the extreme, those of us who had to spend the frosty winter in Mussorie would recall that the good old Bukhari was the only saviour. It was set up early November and would render very useful service till March, and then an entire spectrum of flowers of myriad colours would blossom in the garden. The Bukhari was a most useful contraption : it warmed the room and gave hot water for tea and coffee, and the crackling sound was a delight in itself. Every few hours, charcoal was added to keep the fire raging and warm the soul, and every morning, the ash was removed and put in the garden. The ash would merge with the soil, and prepare it for the spring blossoms…this was common knowledge, and no seminar or workshop had ever been held to convey this fundamental truth that the wheel of life moves along – the organic becomes inorganic ,joins the soil and creates new life.
Now that the power position in Mussorie has improved, the Bukhari has disappeared ‘unsung’ : no epitaph has been written for it. The Academy no longer provides the Bukhari to the officers’ residences, and there is no supply of coal either. Electrical gadgets and diesel/gas based heating systems are more in vogue – they are neater and look more chic, and there is no requirement of cleaning the Bukhari every few days. The flower beds will probably need a dose of micro nutrients and fertilizers which will be made in a factory, and the natural cycle of dust to dust…ashes to ashes…ashes to life will have a disconnect in the proximate time- space domain. For ash will still be produced in the thermal plants, but the process of putting it back to the soil to reinvigorate it will not be so simple now – but will be an issue of logistics, revenue models, financial stakes and competing interests. In fact as energy consumption goes up in every sector, the dependence of thermal power will increase, and also with it the production of large quantities of coal ash. In fact, in the current year, India will be producing 120 million tones of Fly Ash this year.
This figure can only increase with every passing year, as almost everything, including agriculture is now dependent on power consumption. Therefore the need to draw up a comprehensive plan for the utilization of this by-product of power becomes critical – from every angle. As of now, the country is in a position to utilize about 50% of the fly ash that is generated, but the Coal Ash Institute of India is drawing up an Action Agenda to ensure that over the next few years, every single particle of fly ash can be gainfully utilized ,either in the construction/infrastructure sector, or in the agriculture and forestry sectors. This is easier said than done, because the biggest constraint is the mental block that many of those engaged in agricultural operations have about fly ash – and rightly so, because in areas around thermal plants, production and productivity of crops has been affected because of the excessive presence of fly -ash in the air. The issue therefore is not whether it can be applied or not, but the appropriate dosage that will make it both ecologically sustainable and economically viable.
It is true that till about a decade ago, it was regarded as a ‘pollutant waste’, but now there has been a change in its status, and it is now regarded as a ‘resource’ because power utilities have taken the lead in trying to ‘rediscover’ its regenerative properties. In the initial years, the focus was on using fly ash for soil stabilization and solidification, especially in the coal mining areas. It then found a valuable use as an important ingredient for Portland cement and in manufacture of bricks. In an indirect way, the use of fly ash for bricks helps agriculture because in the absence of fly-ash for bricks, precious top soil would be used in the construction industry.
Another area in which fly ash can find abundant use is the construction of highways: it is an important sub base for the road surface, and is used as a mineral filler in the asphalt concrete. However even if cement and brick industry, and the infrastructure sector were to extend their fullest support to a national programme on utilization of fly ash, the target of cent percent use can be achieved only if the agriculture and forestry sector were engaged in a proactive dialogue and interaction with the power utilities which are the primary producers of fly ash.
At a recent seminar (July6-7,09) organized by the Coal Ash Institute in collaboration with the NABARD and the BC Roy Agriculture University of west Bengal, several presentations were made by academics and researchers working in this sector. Field studies conducted under various agro climatic conditions and soil types has shown that fly ash and pond ash can be used in appropriate doses in the cultivation of field crops and forestry species. The use of fly ash can also bring down the cost of cultivation because it can cut down the use of chemical fertilizers, because it can provide some of the required nutrients with or without organic manure. The lurking fear in minds of most people – its negative impact on the ground water and surface water has not been substantiated by any empirical findings. Field trials have also not reported any incidence of trace elements, heavy active elements and radioactive elements in the soil. However it must be acknowledged that these positive results have not been consolidated on a national plane, nor has regular practice of use of coal ash implemented in the farmers field. The main thrust of this seminar was on getting the extension agencies of the state governments and agricultural universities, particularly the Krishi Vigyan Kendra’s to clear their doubts and concerns, and take up a programme of implementing some of these ideas on the farmers fields.
AgriMatters welcomes this initiative, because India is going to be one of the major thermal power producers in the world, next only to China. It is also going to be the world’s second largest producer of agricultural commodities. The challenge is to reach this material to the disaggregated holdings in the country – but given the interest which extension agencies, power utilities and NABARD are taking in the process, it promises to be a win-win situation for all concerned.
Dust to Dust…Ashes to Ashes …Ashes to Life !