Agricultural Farm Management in India

Prabumj's Blog

The main objective of technology-based agriculture must be to reduce input cost while increasing the yield, particularly for small and marginal farmers. Agriculture scientists would like farmers to realise that reduction of chemical-based fertilizers and pesticides can benefit both man and earth over the long run. Farmers in particular would stand to gain as a major portion of their money is spent on buying these chemicals. The focus, they believe, must shift to educating farmers on the value of waste matter being generated in both their fields and homes, and availability of technologies to convert waste into wealth. Their farm economics will definitely improve if they realise and adopt this. It is precisely on these lines that scientists at the Myrada Krishi Vigyan Kendra at Gobichettipalayam, in Erode, Tamil Nadu have beenworking for the past several years in implementing a project called IFD (Integrated farm development model). Also called as…

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How Garbage Disappears Into People’s Pockets

REVOLUTIONS IN MY SPACE: A BLOG BY RITA BANERJI

One in every 5 humans that inhabits planet earth dumps his/her garbage in India.

GARBAGE = FILTH = DISEASE

Hence, one would expect an organized and efficient system of garbage collection/disposal to be a fundamental condition of nation management.  However, garbage has a whole different story in India.  And here it is in pictures.

At first glance it seems that there is no special place for garbage in India! There is garbage everywhere.

It is dumped under trees like this

Empty cartons and plates from the million food vendors that one sees everywhere in India, are piled

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Rationale for Decentralized Production of Biogas and Bioethanol

Clean Energy and Water Technologies

We live in a technological world where fuel and power play a critical role in shaping our lives and building our nations. The growth of a nation is measured in terms of fuel and power usage; yet there are many challenges and uncertainties in fuel supply and power generation technologies in recent past due to environmental implications. Fossil fuels accelerated our industrial growth and the civilization . But diminishing supply of oil and gas, global warming, nuclear disasters, social upheavals in the Arabian countries, financial problems, and high cost of renewable energy have created an uncertainty in the energy supply of the future. The future cost of energy is likely to increase many folds yet nobody knows for certain what will be the costs of energy for the next decade or what will be the fuel for our cars.  Renewable energy sources like solar and wind seem to be…

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Waste-to-Energy Projects in India – Technical Issues

For self-sustaining combustion, there should be a heat content of at least 2500 kcal/kg (about 5000 Btu/lb). Usually below 1500 kcal/kg, it is not recommended for combustion. Indian MSW is infamous for its low heat content (770 to 1000 kcal/kg, on dry basis, sometimes as low as 600 kcal/kg), high moisture content (30 to 55 % by weight) and high inert contents (30 to 50 % by weight). It is a fact that Indian MSW is not directly suitable for incineration. Waste preparation is a must for incinerating Indian MSW. Waste should be dried; inerts removed and heat content improved to about 2500 kcal/kg.

In order to determine whether a thermal processing project is a feasible waste management alternative for any city, the following questions should be addressed:

  • Is source-segregation practiced in the target area?
  • Is the thermochemical technology approved by the MNRE and the CPCB?
  • Is there a buyer for the energy (electricity/CHP) produced by the energy recovery facility?
  • Is there strong political and public support for a WTE facility?
  • Are there enough funds to establish state-of-the-art small modular gasification / pyrolysis plant?

Elements of successful Advanced Thermal WTE Project

  • Waste segregation
  • Waste receiving and storage capability
  • Waste preparation plant
  • Gasification/pyrolysis process
  • Syngas treatment process
  • CHP / Power generation

Refuse-Derived Fuel (RDF) from Municipal Solid Wastes

  • Solid waste is a growing problem in all countries, and a critical problem in almost all the cities of the developing world. Developed countries have in recent years reduced the environmental impact of solid waste through sanitary landfills and high-temperature incineration, as well as conserving natural resources and energy through increased recycling, but the volume of waste generated in developing countries is rising astronomically. Very few cities have adequate solid waste collection and disposal systems, and the accumulating waste threatens health, damages the environment, and detracts from the quality of life. Therefore, it is necessary to make use of all possible waste management technologies to arrest the degradation of environment and foster waste-to-energy technologies.
  • Urban areas of Asia produce about 760,000 tonnes of municipal solid waste (MSW) per day, or approximately 2.7 million m3 per day. In 2025, this figure will increase to 1.8 million tonnes of waste per day, or 5.2 million m3 per day. These estimates are conservative; the real values are probably more than double this amount. Most common method of disposing of wastes is to dump them in low-lying areas on the outskirts of towns which is very haphazard and unscientific. This has serious environmental impacts like water pollution, methane emissions, and soil degradation.
  • The advantages of the refuse-derived fuel plant type are focused mainly on the relatively higher energy content of the RDF fuel, which originates from the pre-combustion separation processing.
  • RDF plant employs mechanical processes to shred incoming MSW separating the non-combustibles in order to produce a high-energy fuel fraction and thus improved efficiency.
  • One of the most appealing aspects of RDF is that it can be employed as a supplementary fuel in conventional boilers. Furthermore, RDF’s energy content is around half that of UK’s industrial coals and nearly two thirds that of low grade US coal.
  • Pelletization scores over mass-burning, anaerobic digestion and composting because the pellets’ energy content is close to that of coal and can be substituted in local industry.
  • A number of widely employed industrial and utility-scale coal utilisation technologies have the potential to co-utilise RDF and coal, such as large-scale pulverised coal-fired power plant boilers, cement kilns, fluidised bed or stoker-fired boilers, coal gasification plant
  • Due to reduction in fuel particle size and reduction in non-combustible material, RDF fuels are more homogeneous and easier to burn than the MSW feedstock.
  • RDF has been successfully burned in a variety of stoker boilers and in suspension as a stand-alone fuel in bubbling and circulating fluidized bed combustion technology boilers. It needs lower excess air and hence works at better efficiency. Also, handling is easier since non-combustibles have been already removed.
  • In utilizing MSW through a pelletization process, additional tonnage of recyclables will be positively selected to take to that market, assisting the developing regions to work towards sustainable development goals, while positively selecting appropriate materials to mix with purchased high BTU materials in the production of the high BTU pellets, that can be used either to replace coal or coke in industrial processes.
  • RDF is a much more uniform fuel than MSW with regard to fuel particle sizing and heating value resulting in a more efficient combustion process. In addition, a majority of the non-combustible material is removed from the RDF before the fuel is fed into the boiler which reduces the size of both the fuel and ash handling systems. These fuel characteristics result in a RDF boiler system which is generally less expensive than a mass-burn system, thereby offsetting the cost of the RDF processing equipment.
  • It is much easier to transport and store fuel pellets to power plants or industries than raw MSW.
  • Advanced thermal technologies like gasification, pyrolysis, and depolymerization are unattractive to developing countries due to their prohibitive costs.
  • Technologies to control the release of air contaminants have improved substantially in the past decade and that, therefore, the releases from modern RDF plants are not high enough to have negative impacts on human health.
  • Air emissions from incinerators should be compared with air emissions from other methods of generating energy. When such comparisons are made, it is found that natural gas power plants are the cleanest way to generate energy but that emissions from waste incinerators are equivalent to or less than the emissions from a coal or oil power plant.
  • Incinerator proponents also assert that the health risks from exposure to the releases from a RDF power plant are substantially less than the risks from many other common activities.