How Polluting Agro Waste Can Be Minimised And Utilised

India has one of the largest agricultural lands in the world and a population exceeding 140 crores, with nearly 70% of people living on agricultural lands.

Out of the total agricultural produce, at least 7% (16 – 17 million tonnes) of grains go to waste each year. This is mostly due to unscientific methods of harvesting and storing food grains. Similarly, huge quantities of vegetables, fruits, milk and milk products get wasted because of improper storing, transportation and distribution. Another factor responsible for wastage is that India’s agricultural sector is highly fragmented compared to other developed countries. An Indian farmer on average has got only 2 to 4 acres and nearly 70% of them have only 2.5 acres of farming land on average. Similarly, other stakeholders including transport companies, traders and whole sellers are also highly fragmented.

To improve agricultural production and minimise waste, it is necessary to improve the present infrastructure facilities and technologies used in various key areas. In addition to this, the government purchase and distribution schemes, price volatility, middlemanship, financing, education and training of farmers are some of the areas where a lot of streamlining and improvements are necessary to bring down and utilise waste. Here is a summary of the facts:

1. Due to a lack of proper and sufficient storage infrastructure such as silos, grains are generally being stored outside, under open shades mostly without provision to protect them from humidity and pests. For example, in 2011, in India, about 10 million tonnes (MT) of grain in the public storage system was reported to have rotted due to improper storage. It might be mentioned here that, this amount of grains is sufficient to feed 140 million people for about a month. In addition to the unscientific grain storage, there are very few cold storage facilities for storing perishable goods like vegetables, fruits, meat, fish, dairy products etc. Roads and transportation facilities in many parts of the country, are extremely inadequate to transport agricultural products to the markets in time and this results in a lot of wastage, particularly during summer months.
2. The government purchase and distribution schemes are found to be inefficient mostly due to faulty bureaucracy and corruption. As a result, farmers particularly the small ones are indirectly discouraged to sell their agricultural products in time with good financial benefits.
3. In India, during the process of food grains reaching from farmers to consumers, a number of intermediaries are involved. Most of the farmers are poor, the middlemen take advantage by controlling the price and supply of agricultural products to the consumers. They create artificial scarcity and sell the products at a high price. During this process, a large number of agricultural products are wasted due to improper and limited storage facilities.
4. Another reason for the wastage of agricultural produce is price volatility. Generally, farmers choose to grow crops, which are profitable and in this process, when a large number of farmers produce the same item, the supply becomes excess compared to the demand and as a result, the price of the crops comes down drastically. In this process, the farmers incur a lot of financial loss to harvest, transport and sell their crops. Each year, thousands of tonnes of material gets rotted due to slow transportation and lack of proper storage facilities. Such a situation took place in case of a fall in the price of potatoes in 2011.

Due to these reasons, at present, a large number of agricultural products get wasted in India whereas a significant percentage of its population does not get two square meals every day. To cut down agricultural waste, efforts have to be made with all sincerity to develop various post-harvest technologies and sufficient provisions have to be made for storage, proper handling and processing of the agro-products. It has been estimated that the extent of losses can be brought down to nearly 50% of the existing label on the adoption of agro-processing technologies.

Since 1950, some efforts are being made by the state and central governments in India to improve the transportation, storage and processing of agricultural products through the development of agro-processing industries. In this regard, no doubt some developments have taken place, particularly in the processing of rice, wheat, oil seeds, fruits, vegetables, jute, sugarcane, cotton, fish and other animal products, but much more is yet to be done.

Since Independence, some efforts are also being made for exporting certain special items including spices. But, our processed products in many cases do not meet international standards. In view of this, India’s share in this sector is about 1% of the total world trade in agricultural commodities. However, fruits and vegetable products have a lot of export potential if their quality can be maintained.

While making various efforts to minimize the wastes through proper storage, timely transportation, distribution and sailing of agro products, different attractive programmes should be undertaken to utilise the wastes to produce value-added products like compost and energy from organic wastes, high pure silica from rice husk, paper from sugar cane bagasse etc. Agricultural waste management can be effective by starting with activities like the estimation of different types of wastes, their proper collection, storage, treatment, transfer and finally their utilisation to produce value-added products.

1. Estimating the amounts of waste and their storage – The different types of waste generated during agricultural production and their amounts have to be estimated in order to plan the successive stages of operation. The amount of waste generated in agricultural fields as well as at the place of livestock operation should be assessed seasonally so that a suitable plan can be worked out for collection and storing those in a proper manner for further processing.

To collect different types of agricultural wastes, various methods and infrastructures for collection, labour requirements, types of transportation etc. have to be properly planned and their collection should be scheduled as per the requirements for various types of wastes. The storage facility for different types of wastes has to be done properly keeping in view the seasonal effects on the wastes so that the wastes are not lost and pollution of the surroundings is avoided. The storage period for any type of waste has also to be properly estimated keeping in view the utilization scheduled, so that, the facilities are utilized properly and economically.

1. Transfer of wastes – The transfer of wastes after collection to the storage yard and transfer of wastes from the storage yard to the place of treatment have to be programmed properly. Necessary infrastructures for the transfer of wastes without causing any harm to the surroundings, have to be planned and implemented. The wastes being solid or in slurry form, proper transportation of those has to be planned. The wastes should be properly analyzed before sending those for processing. Before storing the organic wastes meant to process for different purposes such as extracting energy, producing manure, using as animal feed, mulching as plant nutrients etc, should be separated out from each other. But earlier to this, other wastes like metal scraps, plastics, glasses etc. are to be separated out for sailing to the respective industries for recycling.
2. Processing of the wastes – Different types of organic wastes meant for specific purposes can be selectively identified and processed in time to get more value-added products. For example, some agricultural wastes like bagasse should be utilized as a feed stalk or for paper making; cotton wastes can be used for mushroom cultivation; jute cane can be used to produce particle boards and the rice husk can be used to produce high-grade silica, insulation materials, particle board as well as a source of fuel. In this way, some of the wastes can be utilized as raw materials to produce valuable byproducts. After these, the rest of the organic wastes can be utilized through anaerobic digestion to produce high-grade manure and domestic fuel gas instead of using these valuable wastes in landfilling as is generally practised in most parts of India. One tonne of organic waste (on a dry basis) can produce about 800 m³
   of fuel gas and 400 kg of manure. Other types of wastes like rejected agricultural implements, plastics, rejected bags etc. can be separated out for sale to the respective industries for recycling.
3. Agro-Industrial Waste Management – The agro-industries which use agricultural produce of various types, also generate a number of wastes which have to be managed properly in order to prevent pollution as well as to promote economic benefits by producing value-added products from these wastes. In this case, waste management can be done in two major ways which can be carried out in the following prioritising order.

• Waste Minimisation: Waste minimisation in the agro-industrial sector can be carried out through the proper use of raw materials and applying appropriate technologies. At first, the raw materials of agro-industries should be used efficiently so that, the waste generation is minimum. In addition to this, the waste produced should be as far as possible kept in a solid state or as a concentrated sludge form, so that the volume can be minimized and facilitate economic storage and transportation. In agro-based industries, different types of wastes generated should be segregated so that, these wastes can be utilised subsequently. For example, removing suspended solids in palm oil mill effluent by decantation, improves in minimisation of the solid from waste water and also reduces the waste load and treatment cost. In a plant, grease wastes, non-grease wastes, clear water used for chilling, condensing and cooling operations, surface drainage, sanitary wastes, etc. should be collected and treated separately. This will help in streamlining and economising agro-industries production.
• Waste Reuse: In many cases, the waste can be converted into valuable raw material for other industries. For example, the bagasse in sugarcane industry can be used for making quality papers. Another example is the tuna fish canning industry where tuna pre-cooking water can be utilised for the production of fish extract, while the recovered solids can be sold as fishmeal. In the years when the oil price was very high, biogas production from anaerobic treatment of palm oil wastewater was very attractive.

            Some of the major activities in Agro Waste Management (AWM) are been summarised below:

• The reduction of waste refers to reducing the amount of unnecessary waste by careful preparation of raw agricultural materials. The Green House Gas (GHG) emissions can be reduced in a number of areas including fertilisers and pesticides production, land use change and forestry (deforestation for agriculture) and energy (harvesting).
• A number of agricultural wastes can be reused for economising production. In this regard some typical examples are given below:
• The wastes like rice husk can be used directly for soil mulching. Such reuse of plant residues can also avoid a certain amount of GHG emissions from burning and open air composting processes which are being practised at present.
• Livestock wastes can also be used as a food source for fish after anaerobic digestion.
• The straw after harvesting rice or wheat and some of the byproducts of post-harvesting processes can be utilised as food for animals, for mushroom cultivation etc.

Unscientific farming and harvesting, inadequate storage and transport facilities, and lack of proper communication and coordination between farmers, governments and other stakeholders, have resulted in a considerable amount of wastage in different sectors of agriculture including animal husbandry. It is, therefore, essential to use modern technologies and develop sufficient infrastructural facilities to increase agricultural production, storing and transportation facilities as well as develop agro-based industries mostly involving farmers and their family members with a zero waste approach. It is also suggested that, necessary steps should be taken to adopt the 3R management system (Reduce, Reuse and Recover) in waste management. Instead of using organic wastes in landfilling, it would be advisable if various schemes are made throughout India where organic wastes through anaerobic digestion are utilised for producing organic manure and fuel gas for cooking and other agricultural activities including fulfilling the energy requirements of farmers and agro-industries. The implementation of these programmes will go a long way in improving considerably the agricultural production in a clean environment with zero waste.