WEALTH FROM WASTE ANIL KUMAR SCHOOL OF BIOTECHNOLOGY DEVI AHILYA UNIVERSITY KHANDWA ROAD CAMPUS INDORE , INDIA

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1 WEALTH FROM WASTE ANIL KUMAR SCHOOL OF BIOTECHNOLOGY DEVI AHILYA UNIVERSITY KHANDWA ROAD CAMPUS INDORE , INDIA Tel No : , Fax No : ak_sbt@yahoo.com

2 WELTH FROM WASTE Now a days we very frequently come across a term "ECO FRIENDLY" products. Even in Newspaper you will find our Government and other social organizations appealing about the use of eco-friendly products i.e. the products which are friends of ecosystem; do not harm it and have harmony with the Environment. Here "eco" means ecosystem i.e. a particular area like ponds, forests, plain grasslands etc. where all living organisms whether it be animals, humans, plants or microorganisms not only interact among themselves but also with their Environment.

3 In nature, there is a beautiful relationship between these living and non-living factors. So the products like paper, jute, natural gas etc. which after use get easily assimilated in the environment are said to be eco-friendly but products like plastics, polythene those are most widely used are not eco-friendly as first they can not be broken down into simpler compounds and even if they are subjected to recycle, large amounts of poisonous gases are liberated that may damage our environment. But the use of ecofriendly products is not sufficient alone to keep the environment clean and healthy. If the wastes obtained by the use of such products are not cleaned up or recycled properly their accumulation can create hygienic problems. As a result of population explosion and vast industrialization esp. in developing countries such a large amount of waste is being generated every day that if it is not cleaned up and recycled the day is not far away when our beautiful planet will become a garbage dump. India alone produces millions of tons of waste every year.

4 Wastes Produced in India Waste Quantity Municipal solid waste 27.4 million tonnes/year Municipal Liquid waste million litres/day class I & II cities Distillery (243 Nos.) 8057 Kilolitres/day Press mud 9 million tonnes/year Food & Fruit Processing waste 4.5 million tonnes/year Willow dust 30,000 tonnes/year Dairy waste million litres/day Paper & pulp industry waste 1.6 million litres/day Tannery (2000 Nos.) 52.5 million litres/day

5 Besides health and environmental hazards what kind of disaster can a garbage dump bring, a tragedy in Philippines is an example. This accident took in place on 10th July A garbage dumping site was established out of Manila in It became the primary site for dumping of metro Manila's garbage. It accepted about tons of trash very day for years. Over the time it filled in the once-verdant valley and began growing into a mountain of garbage called "Payatas" seven stories high. It covered about 55 acres where lives a community of 50,000 to 60,000 people. About 10,000 families earn their living by reselling recyclable materials. One day a large portion of the garbage mountain collapsed engulfing 400 houses that had been built around the mountain's perimeter. Downed power lines sparked the methane gas that escaped from garbage and produced large fires despite of rains. This killed several hundred people and other several hundreds remained missing.

6 In recent years, environmental pollution has become a global problem. Large amounts of agricultural, domestic and industrial wastes generated have potential detrimental effects both on the environment and on human health. Itai-ltai and Minanata diseases in Japan, are just two examples of the effects of air and water pollution on human health. Problem of waste could be mitigated through adoption of improved and scientific methods and environmental friendly technologies for collection, processing before it is disposed off. These technologies not only reduce quantity but also improve the quality of waste to meet the pollution standards, besides generating substantial amount of energy. Now technologies are available to harness energy and power as a by product of treatment process. Biotechnology is one of the future oriented technologies that will play a major role especially in the exploitation of biomass energy.

7 Classification of Waste Waste Solid Liquid 1) Human excreta 1) Domestic sewage 2) Household waste 2) Effluents from 3) City garbage community, 4) Commercial waste institutional and 5) Industrial waste industrial activities.

8 Waste (on the basis of chemical nature) Inorganic Waste Organic Waste Mixed Waste Generated by Agricultural Discharged Metallurgical products, dairy from industries Chemical and milk products, dealing with Industries, slaughter houses, textiles, dyes, coal mines etc. sewage, forestry gas, plastic, etc. wool, leather, petroleum etc.

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10 Organic Waste Utilization in Agriculture: Depending upon the material, organic wastes can supply macronutrients (N, P & K) and micronutrients to the soil for use by crops. These materials can replace part of or all synthetic fertilizers used in an operation. Adding organic matter to soil can improve their physical properties (infiltration, water holding, structure etc.) and chemical properties (cation exchange capacity, fertility etc.). Through agricultural utilization of organic wastes, producers can be benefitted (and possibly derive marketing potential) from materials that otherwise may be placed into landfills or present environmental pollution problems. By implying proper waste management facilities and treatment we can prevent wastes from finding their way into the environment. Let's see how can we bring wealth from waste. WASTE UTILIZATION

11 2) Composting: Composting is a biological treatment in which microorganisms (bacteria, fungi and actinomycetes) decompose and stabilize organic material. Managing a composting system generally involves providing an environment that supports (maximizes) microbial activity. As microbes consume organic material to grow and metabolize, some of the waste mass (including nutrients) is immobilized in the cells of the microorganisms. As a result of microbial metabolism water vapor, CO 2 and heat are released, loss of water vapor results in a gradual drying of the waste; loss of CO 2 and water vapor result in reduction of mass.

12 Heat generated in composting increases temperature of the material, which generally increases microbial activity. High temperatures maintained in the composting process can also destroy weed seeds, insects and pathogens. Since compost is a stable, bulky material, it is relatively easy to handle and transport with conventional equipment. Because it has relatively low moisture content, compost may be less expensive to transport than many untreated high-moisture wastes. Further because of its biological stability, it is easy to store and unlikely to smell at the time of application.

13 3) Bio-gas Production: Biogas is popularly known as "Gobar gas" in India. It's also called as swamp gas, fuel gas, wet gas, sewer gas, marsh gas. Composition: Methane 60-65% CO % Hydrogen sulphide traces Ammonia, water vapor and other impurities Uses: a) Biogas burns with blue flame and provides a clean fuel for cooking and lighting biogas burner and lamps. b) It provides reasonably efficient fuel for both spark ignition (petrol) and compression ignition (diesel) engines. c) It can be utilized for electricity generation. 1 kwh of electricity can be generated from 0.7m 3 of gas.

14 However it is economical only for large sized plants and it requires high initial capital investment. d) It can be used as vehicle fuel. Being gaseous fuel biogas provides excellent cold starting for vehicles because unlike petrol it does not first have to be vaporized. Once started, engine performs well immediately with no sluggish warmup. Animal wastes, urban wastes including night soil and crop residues can be used as feed for biogas production.

15 4) Hydrogen Production: Hydrogen gas is used as a) raw material in the manufacture of NH 3. b) as a fuel in welding due to high flame temp achieved when burned with oxygen. c) reducing agent. d) industrial fuel. e) in hydrogenation of oils and fats. f) liquid hydrogen is an important cryogenic fuel. Hydrogen is virtually an ideal fuel since it burns in air to form non-polluting hydrogen vapor. It can be easily transported. It's a renewable clean or non-polluting fuel having calorific value of about 34 Kcal/gm. Animal and plant wastes can be used for its production.

16 5) Production of Hydrocarbons: Recent investigations have shown that many plants contain hydrocarbons and other substances similar to petroleum in their composition. Such plants are selected and grown for energy purposes either for direct use or as feedstock for more convenient liquid fuel or other energy chemicals. These plants can be used either to get diesel fuel or after their conversion, high quality liquid fuel. Some examples of plants that can be used for production of hydrocarbons are Aloe vera Givortia rottaliiformis Euphorbia antiquorum Jatropha curas Plumeria alba Bassia latifolia Nerium odorum Calotropis procera Cryptostegia grandiflora,etc.

17 6) Enzyme production: Studies show that the wastes can be used for the production of valuable substances like enzymes. The enzyme cellulase is of significant use in the production of ethanol, glucose, high fructose syrup as well as in fruit juice industry and cell wall disintegration. It is also used in animal feed formulation along with protease. Cellulase can be produced by solid state fermentation using begasse wheat bran, rice bran, sugar beet pulp, rice straw etc. as raw material. 7) Ethanol Production: Ethanol can be produced from waste biomass by a variety of production techniques that are based on either biotic or abiotic mechanism. In all cases the components of waste biomass sources that are resistant to direct fermentation are transformed to a more useful form that is fermented to produce ethanol among other products of value.

18 8) In Wood Cement Composites: Forest waste as well as saw mill residues and horticulture waste contain substantial amount of ligno-cellulosic material, hence investigations are being carried out on Pine (Pinus roxburghii) needles, saw dust of Eucalyptus and Populus species and the pruning waste obtained from the fruit trees, for wood cement composites preparation. 9) As Animal Feed and Feed Supplements: Crop residues and other organic wastes are convertible to animal feed often when production of food crops exceed the edible food materials. Microbial processing' or physiochemical treatment of organic wastes and residues usually is quite effective in increasing the nutritive value of these materials.

19 Crop residues treated with alkali (e.g. NH 3 ) when feed to cattle have potential to double the roles of weight gain and milk yield, if the amount and quality of protein in their diet are not limiting. Treatment of bagasse with alkali greatly increases its digestibility. Animal feed protein supplement can be prepared from rice straw or sugarcane bagasse by alkali pre-treatment followed by fermentation with a mixed culture of Cellulomonas spp. and Alkaligens spp. The former species breaks down the cellulose and the latter microbe grows on the degradation product and increases the cellular biomass. These microbial cells contain about 50% protein of a quality comparable to that of soybean protein. Another highly useful method of producing animal feed from waste material involves the growth of algae in waste water containing human and animal wastes. The algae grow rapidly in oxidation ponds may be harvested, sun dried and used as protein rich supplements to animal feeds.

20 Thus by recycling the waste we can: A) keep the environment clean and pollution free, B) increase the food production and produce a variety of valuable commodities and C) meet world's energy demand. Thus by applying wit of science and technology we can make human being more eco-friendly and prove that science is a boon not bane.