INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 1, No 6, Copyright 2010 All rights reserved Integrated Publishing Association

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1 INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 1, No 6, 2011 Copyright 2010 All rights reserved Integrated Publishing Association Research article ISSN Cost Effective Solution for Carcass Disposal in India Department of Chemical Technology, Sant Longowal Institute of Engineering and Technology, Longowal, Sangrur, Punjab, India ABSTRACT To dispose of dead animals, specific sites (Hadda Rorri sites) have been earmarked in villages and towns in India. However, there is no organized system for the disposal of carcasses. In the absence of an organized and scientific system of disposal of dead animals, it has become a major environmental hazard. While the skin is removed for its market value, the flesh is allowed to putrefy without any control resulting in highly repellent stench permeating into surrounding atmosphere. The dead animal is flayed for its hide and the remaining part is left behind to putrefy in open. As no enclosure is provided, this attracts vultures and dogs polluting the environment and creating health hazards. A nauseating stinking smell is emanated from these sites which vitiates the whole ambience of the area and even erodes the economic value of the surrounding land. These places are unguarded and stray dogs & predators consume the dead animals with every danger of spread of disease. Different technological options like rendering and composting have been studied and a cost effective environment friendly solution having a payback period of about 2.5 years have been arrived at. Key words: carcass, rendering, composting, value addition, odor control 1. Background Presently, there is no organized and scientific system of disposal of dead animals. Although land (hudda rorri sites) has been earmarked for this purpose in almost all the villages and towns, but in absence of scientific inputs and technological support, the disposal has become a major environmental hazard. While the skin is removed for its market value, the flesh is allowed to putrefy without any control resulting in highly repellent stench permeating into surrounding atmosphere. This, besides being a health risk, dips the commercial value of property and affects quality of life. 2. Existing Status The interaction with the concerned government departments revealed that the handling and disposal of carcasses of these animals is given on contract in cities and in some of the big villages. In villages in general, the age old system is in vogue where of the persons from the weaker section of the society handle the dead animals for the market value of the hide. It was found that no attention is being paid by the contractors for a proper management of hadda rorri sites. The dead animal is flayed for its hide and the remaining part is left behind to putrefy in open. As no enclosure is provided, this attracts vultures and dogs polluting the environment and creating health hazards as shown in figure 1 below: Received on February, 2011 Published on April

2 Figure 1: A typical picture of hadda rorri site A rendering plant located at Ladhowal near Phillaur where dead animals are being processed daily to manufacture tallow, bone meal and meat meal was also studied. This plant, though commercially flourishing, is a typical case of unscientific management and a major source of environmental de gradation (Figure 2) Figure 2: Pen pans used for cooking carcasses About 20 dead animals are processed daily. After de skinning whole carcass is boiled in open big sized pan for hrs. The tallow is skimmed off and the effluents generated are allowed to stagnate on to surrounding land without any treatment. The bones and cooked meat is taken out. While the bones are sent to the bone meal plant, cooked meat is crushed and used as meat meal ingredient. The area around these plants is highly polluted and the offensive odor permeates for kilometers around. The remnants of animal parts are scattered all over the area which presents a ghastly site as shown in Figure 3 Figure 3: Organs of the dead animals being disposed of in open 1374

3 3. Different technological options Literature survey revealed that there can be following technological solutions to this problem: Dry rendering (Workers Manual, 1999) Composting (Herbert,1992) Wet rendering (Brent et al., 2004) The dry rendering process is as such very expensive and hence it is not economically feasible. The composting process has been implemented successfully is some countries (Composting guide,2005) however, there are many operational problems and it has not been successful any where in India. Discussions with experts revealed that the Central Leather research institute has set a wet rendering plant in kanpur which is working efficiently for the last five years. Although this plat was located in the residential area yet, there was no offensive odor in the surroundings. Besides containing pollution the plant has a pay back period of about 2.5 years due to recovery of bye products like, skin, hide, tallow, bone meal, meat meal and bone and meat meal etc. Wet rendering along with the details of the plant have been described as under. 4. Wet rendering Process Wet rendering involves removal of hides/skin at the flaying yard from the Carcass, separation of rumen contents and horns and hooves. The rest of the animal body consisting of flesh, tissues and bones is cooked in a cooker for obtaining tallow and cooked meat and bones. Limited amount of water is added in the cooker for the production of steam. The separation of cooked meat from bones is carried out manually. The separated bones are crushed in the bone crusher for obtaining bone meal. The separated cooked meal is generally sun dried. However, during rainy season this meat is first minced in the meat mincer and then dried in a rotary dryer. The dried meat is pulverized in the pulverizer for producing meat meal. The meat meal can also be mixed with bone meal for making meat cum bone meal. The various unit operations involved in a typical wet rendering plant are enunciated below: 4.1 Cooking operation The cooking vessel is based on the principle of an autoclave. It is made up of a metallic drum with circular perforated plate that rests on three angular supports. The outer surface of the vessels is lagged with asbestos to prevent loss of heat. The asbestos is covered with thin metallic sheet to avoid soaking. Figure 4: Pressure cooker for boiling of meat and Bones Figure 5: Wire mesh container for filling the meat 1375

4 Figure 6: Arrangement for loading and unloading of pressure cooker The top end of the vessel is provided with a flange and a groove. A water level gauge and a draw off valve have been provided. The photographs of a typical rendering pressure cooker along with its inner details are shown in Figures. 4, 5 and Extraction of tallow The slurry containing tallow is colleted into an open pan from the rendering vessel. It is allowed to cool so that fat will solidify on the top layer. Fat is scooped off and collected in a separate vessel. There are impurities such as water with soluble proteins and some minerals. Hence the fat containing water and other impurities has to be cooked in an open pan by adding alum and salt. Water is allowed to get evaporated and then purified tallow is collected. The bones after cooking become soft and pliable. These bones are separated from soft tissues manually by the workers. This separation is shown in Figure 7 & 8 Figure 7: Meat and bones after boiling 1376

5 Figure 8: Separation of bones and meat after boiling 5. Cost benefits analysis of proposed Rendering Process: The economic viability of this technology is for processing at least four to five carcasses Per day. Considering only 50% of big size animals, 60 big size animals will be received in one month and around 700 big sized animals will be received per year. Thus, the cost benefit analysis is calculated considering only the big sized animals. The estimated fixed cost of a typical wet rendering plant for processing 4 5 carcasses per day is Rs lacs and it requires an annual working capital of Rs lacs. The value addition due to recovery of various products is estimated as Rs. 9.6 lacs per annum. Thus, the net annual profit would be Rs. 5.6 lacs and such a plant has a payback period of 2.5 years only. 6. Conclusion There are three technological options for disposal of carcass. These are dry rendering, wet rendering and composting. However, under Indian conditions the best possible cost effective and environmentally solution is wet rendering. This will not only provide a practical solution for controlling offensive odor pollution but will also have economic benefit to the poor people engaged in carcass handling by recovery of bye products like, skin, hide tallow, bone meal and meat meal etc. This technology has an estimated pay back period of only 2.5 years. References 1. Workers manual on carcass recovery and byproducts utilization, Central Leather Research Institute Adyar, Chennai, Composting animal mortalities of the farm, Herebert L Brodie Lewis E Carr, Department of Biological resources engineering University of Maryland College park, Composting facility Code No 317, Natural resources conservation service conservation practie standard December

6 4. Whole animal composting of dairy cattle Michael Looper extension Dairy specialist, New Mexico State University May Carcass Disposal: A Comprehensive Review National Agricultural Biosecurity Center Consortium USDA APHIS Cooperative Agreement Project.Carcass Disposal Working Group, Brent Auvermann,Ahmad Kalbasi, Anindita Ahmed, Texas A & M University August Composting Animal Mortalities: a producer s Guide, University of Saskatchewan, Canada, January Composting Deadstock a Producer s Guide to Effective Mortality Management, Dead Animal Composting H. M. Keener and D. L. Elwell, Harold M. Keener, Dept. of Food, Agricultural, and Biological Engineering, OARDC, 1680 Madison Avenue, Wooster, OH Rynk, R.(Ed.) On farm Composting Handbook, NRAES 54. Northeast Regional Agricultural Engineering Service, Ithaca, N.Y. White, D.G., J.M. Regenstein, T. Richard and S. Goldhor Report on Composting Animal Mortalities By Debra Elias Morse, July 2001, University of Minnesota