PROJECT REPORT ON ESTIMATION OF BIOMASS RESOURCES BY VINAY PANDEY

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PROJECT REPORT ON ESTIMATION OF BIOMASS RESOURCES BY VINAY PANDEY

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PROJECT REPORT ON ESTIMATION OF BIOMASS RESOURCES BY VINAY PANDEY

  1. 1. PROJECT ESTIMATION OF BIOMASS RESOURSES IN DIFFERENT VILLAGES OF W.B AND BIHAR. 1. INTRODUCTION :Biomass has always been an important energy source for the country considering the benefits it offers. It is renewable, widely available, carbon-neutral and has the potential to provide significant employment in the rural areas. Biomass is also capable of providing firm energy. About 32% of the total primary energy use in the country is still derived from biomass and more than 70% of the country’s population depends upon it for its energy needs. Ministry of New and Renewable Energy has realised the potential and role of biomass energy in the Indian context and hence has initiated a number of programmes for promotion of efficient technologies for its use in various sectors of the economy to ensure derivation of maximum benefits Biomass power generation in India is an industry that attracts investments of over Rs.600 crores every year, generating more than 5000 million units of electricity and yearly employment of more than 10 million man-days in the rural areas. For efficient utilization of biomass, bagasse based cogeneration in sugar mills and biomass power generation have been taken up under biomass power and cogeneration programme. Biomass power & cogeneration programme is implemented with the main objective of promoting technologies for optimum use of country’s biomass resources for grid power generation. Biomass materials used for power generation include bagasse, rice husk, straw, cotton stalk, coconut shells, soya husk, de-oiled cakes, coffee waste, jute wastes, groundnut shells, saw dust etc. With the largest rural population in the world, India is facing a huge electrification challenge. Today, 64.5% of India is electrified, with an electrification rate of 93.1% in urban settings but only 52.5% in rural areas. This has been achieved mainly through grid extension or small-scale renewable energy systems. Strong political will and sufficient funds have, since the beginning of the 11th Five-Year Plan, accelerated the speed of electrification. But India is currently faced with insufficient electricity generating capacity, which is seriously hindering the implementation of future rural electrification programmes and undermining their viability.
  2. 2. At the present status of our country, un electrified households are very high in Bihar, Jharkhand, and Orissa, UP, NE, West Bengal, and Chattisgarh. In this thesis I have tried to give electricity for few hours to the village through Biogas by using the raw materials (like, cow dung, house waste, paddy straw etc.) from that certain village. The generation of electricity through biogas is cheaper than other mode of electricity generation. After an initial investment in the system, there is no need to spend money on fuel. On the other hand, in these types of energy generation we can get clean energy. This energy generation process is also eco friendly than any other mode of energy generation technique. In this thesis I have tried to give electricity for almost 3 or 4 hours to each house of two villages namely, Ramnagar (Hooghly District) of West Bengal and Behea (Bhojpur District) of Bihar. For electrification of these two villages I have used Biogas!! 2. Status of Rural Electrification in West Bengal & Bihar The economy of a developing country depends on growth in industry, agriculture, service, information & technology and infrastructure sector. The major input required for the growth of these sectors is power or electricity. Power also plays an important role in social sectors such as health and education. At present power has become an essential requirement for all walks of the life. A village was considered to be electrified if the electricity is being used within its revenue area for any purpose whatsoever prior to October 1997. After October 1997, the definition of electrified village was modified and it stated that a village should be classified as electrified if the electricity is being used in the inhabited locality, within its revenue area for any purpose whatsoever. These two definitions of electrified village were so vague that if even one household uses electricity or within inhabited locality electricity used for any purpose irrespective of number of users exist in the village than village used to consider as electrified. In reality, the electrification of villages, which had been carried out as per definitions stated above, did not serve any purpose and did not contribute to any betterment of rural people who constitute more than 70 percent of total population.
  3. 3. “A village is termed as electrified provided  Number of households electrified should be at least 10% of the total number of households in the village.  Electricity is provided to public places like schools, Panchayat offices, health centers, dispensaries, community centers, etc. and  Basic infrastructure such as distribution transformers and distribution lines are provided in the inhabited locality as well as the dalit basti/hamlet where it exists. (For electrification through non-conventional energy sources a distribution transformer may not be necessary)” With implementation of this definition, the number of un-electrified villages has increased. To judge the ground situation, the data of Census of India, 2003, which provides the data on source of lighting (i.e. electricity, kerosene, solar energy, and other oils, any other as source of lighting) used at household level by villages, can be used. From 2003 census data, one can estimate the number of un-electrified villages which does not meet the criterion of at least 10 % of total number of households electrified in the village. This estimated number of un-electrified villages is likely to increase if all the three criterions are applied. Table showing Rural Electrification of West Bengal and Bihar State Total no. of No. of unelectrified households in households in villages villages West Bengal 11161870 8899353 79.7 Bihar 12660007 12010504 94.9 Source: Ministry of Power, Courtesy: Powerline 2/2005 % unelectrified
  4. 4. 2.1 Rural Households Electrification (as per 2001 census)  Total No. of rural households : 111,61,870  Households electrified : 22,62,517  %age of electrified rural households : 20.27% 2.2 Village Electrification in West Bengal  Total No. of inhabited villages : 37910  No. of villages reported as electrified : 32271  %age of Villages Electrified : 84% In West Bengal, out of 37910 villages there were 2275 villages where none of the households had the access to electricity and 3,791 villages having less than 10% of households using electricity. Thus as per present definition, in 2001, there were 6066 un-electrified villages in the state accounting for 16 % of total villages. 2.3 Rural Household Electrification (as per 2001 census)  Total no. of rural households : 126,60,007  Households electrified : 6,49,503  %age of electrified rural households : 5.13% 2.4 Village Electrification in Bihar  Total No. of inhabited villages: 67513  No. of villages reported as electrified : 48280  %age of village electrification : 71.5 In Bihar, out of 67513 villages there were 17317 villages where none of the households had the access to electricity and 1924 villages having less than 10% of households using electricity. Thus as per present definition, in 2001, there were 19241 un-electrified villages in the state accounting for 28.5 % of total villages.
  5. 5. To solve this problem of unelectrified households of villages in West Bengal and Bihar, an attempt has been made the estimate of electrification through Biogas resources. 3. Electrification of Village through Biogas The data is analysed by using various parameters such as size of village, percentage of electrified households in the village etc. To know about the present scenario/status of electrification the data can be updated at village level and can be monitored efficiently and effectively. The present status of electrification of villages and households is also provided in above chapters for convenience of user of this report. I hope that this paper may provide inputs to planners to prepare the strategy to achieve the goals at various levels and to provide electricity to more number of villages and households in more economical way. 3.1 Estimate of Electricity generation from biomass in Village Ramnagar (Hooghly) The number of houses in Ramnagar = 2000(approx) In each house there are 2 no. of cow (Avg) Each cow is giving 9kg – 10kg cow dung. (Avg) Therefore,  From each house we are getting 18 – 20kg cow dung  From each house we are getting 900gm – 1 kg house waste.  From each house we are getting Paddy straw according to season  From each house we are getting Paddy straw according to season In Ramnagar village total area 4500 Ekar, within this area 3000 Ekar is used for Paddy. Now, 1 Ekar = 3 bigha 3000 Ekar = 3000 * 3 bigha = 9000 bigha
  6. 6. We are getting Boro Paddy 14 mon (Avg) from one bigha as per details given by villagers who is cultivating Paddy in their fields. From total Ramnagar village within these 4 months we are getting = 9000 * 14 mon Paddy = 126000 mon Paddy And we know, 1 mon = 40 kg i.e. 126000 mon = 126000*40kg = 5040000 kg And From 100 kg Paddy we are getting 40 kg straw (after threshing the Paddy) Than, From 1 kg Paddy we are getting = 40/100 kg Straw So From 5040000 kg Paddy we are getting = 40*5040000/100 = 2016000 kg straw = 2016 ton straw.  From September to October (2 months) – Kalma Paddy From Ramnagar village we are getting Kalma Paddy 8 mon (Avg) from 1 bigha. Therefore, From total village we are getting = 8*9000 mon = 72000 mon = 72000*40 kg (1 mon = 40 kg) = 2880000 kg And From 100 kg Paddy we are getting 40 kg straw (after threshing the Paddy) Than, From 1 kg Paddy we are getting = 40/100 kg Straw So From 2880000 kg Paddy we are getting
  7. 7. = 2880000*40/100 = 1152000 kg straw = 1152 ton straw From February to April (3 months) – Aman Paddy From Ramnagar village we are getting Aman Paddy 10 mon (avg) from 1 bigha Therefore, From total village we are getting = 10*9000 mon = 90000 mon = 90000*40 kg (1 mon = 40 kg) = 3600000 kg And From, 100 kg Paddy we are getting 40 kg straw (after threshing the Paddy) Than From 1 kg Paddy we are getting = 40/100 kg straw So From 3600000 kg Paddy we are getting = 40*3600000/100 kg straw = 1440000 kg straw = 1440 ton straw In Ramnagar village total no. of houses 2000 (approx) We are getting Raw materials of Biogas (Per day) – 1. Cow dung (2000*18) kg/day = 36000 kg/day = 36 ton/day (Avg) 2. House waste (1*2000) kg/day = 2000 kg/day = 2 ton /day (approx) 3. Paddy straw From May to August (4 months) We are getting Paddy straw = 2016 ton 4 months = 4*30 days =120 days So we are getting Paddy straw
  8. 8. = 2016/120 ton/day = 16.8 ton/day = 17 ton/day (approx) 4. Paddy straw From September to October (2 months) We are getting Paddy straw = 1152 ton 2 months = 2*30 days = 60 days So we are getting Paddy straw = 1152/60 ton/day = 19.2 ton/day = 19 ton/day (approx) 5. Paddy straw From Febraury to April (3 months) We are getting Paddy straw = 1440 ton 3 months = 3*30days = 90 days So we are getting Paddy straw = 1440/90 ton/day = 16 ton/day (approx) Now, from (May- August) Total feed stalks (Cow dung, House waste, Paddy straw) = (36 +2+17) ton/day = 55 ton/day BIOGAS 55 ton/day (feed stalks) ↑ —————————→ DIGESTOR —————→ Digested (waste) From, (Sep-Oct) Total feed stalks (Cow dung, House waste, Paddy straw) = (36+2+19) ton/day = 57 ton/day From, (Feb-April)
  9. 9. Total feed stalks (Cow dung, House waste, Paddy straw) = (36+2+16) ton/day = 54 ton/day From, (Nov-Jan) Total feed stalks (Cow dung, House waste, Paddy straw) = (36+2) ton/day = 38 ton/day 1. Now From –May to August Total feed stalks = 55 ton/day Type Quantity *Sp. Gas quantity Generated Gas (ton/day) (Normal m3/ton) (m3/day) 1.Cow dung 36 43 1548 2. House waste 2 270 540 3. Boro Paddy 17 277 4709 * This specific values are got from Biomass Gasification Industry Therefore Total Generated Gas = (1548+540+4709) m3/day = 6797 m3/day 2. From – September to October Total feed stalks = 57 ton/day Type Sp. Gas quantity Generated Gas (ton/day) 1. Cow dung Quantity (Normal m3/day) (m3/day) 36 43 1548 2. House waste 2 270 540 3. Kalma Paddy 19 277 5263 Total Generated gas = (1548+540+5263) m3/day = 7351 m3/day 3. From –February to April
  10. 10. Total feed stalks = 54 ton/day Type Sp. Gas quantity Generated Gas (ton/day) 1. Cow dung Quantity (Normal m3/day) (m3/day) 36 43 1548 2. House waste 2 270 540 3.Aman Paddy 16 277 4432 Total Generated Gas = (1548+540+4432) m3/day = 6520 m3/day 4. From – November to January Total feed stalks = 38 ton/day Type 2. House waste Sp. Gas quantity Generated Gas (ton/day) 1. Cow dung Quantity (Normal m3/day) (m3/day) 36 43 1548 2 270 540 Note: There is no cultivation of Paddy between Novembers to January in Ramnagar village Hooghly (data collected through door to door visit in village). Total Generated Gas = (1548+540) m3/day = 2088 m3/day From (1m3) Biogas we can get (2kWh) Electricity 1. During May to August: 1 m3 Biogas = 2kWh Electricity : 6797 m3 Biogas = (6797*2) kWh/day = 13594 kWh/day Therefore per house will get 13594/2000 kwh/day = 6.797kwh/day = 7kwh/day (approx.) Now, 7kWh=7000watt h=4.8*60 watt*24 hour
  11. 11. Therefore, each house will get 5 no. of 60 watt bulb for 24 hours. 2. During September to October: 1 m3 Biogas = 2kWh Electricity : 7351 m3 Biogas = (7351*2) kWh/day = 14702 kWh/day Therefore per house will get 14702/2000 kwh/day = 7.3kwh/day Now, 7.3 kWh=7300 watt h=5*60watt*24 hour Therefore, each house will get 5 no. of 60 watt bulb for 24 hours. 3. During November to January 1 m3 Biogas = 2kWh Electricity : 2088 m3 Biogas = (2088*2) kWh/day = 4176 kWh/day Therefore per house will get 4176/2000kWh/day = 2.088 kWh/day Now, 2.088kWh=2088watt h=1.45*60watt*24hour Therefore, each house will get 1 no. of 60 watt bulb for 24 hours. 4. During February to April 1 m3 Biogas = 2 kWh Electricity : 6520 m3 Biogas = (6520*2) kWh/day = 13040 kWh/day Therefore per house will get 13040/2000kWh/day = 6.52kWh/day Now, 6.52kWh=6520watt h=4.5*60watt*24hour Therefore, each house will get 4 no. of 60 watt bulb for 24 hours.
  12. 12. 3.2 Estimate of Electricity generation from biomass in Village Behea (Bhojpur, Bihar) The number of houses in Behea = 1500(approx) In each house there are 2 no. of cow (Avg) Each cow is giving 9kg – 10kg cow dung. (Avg) There fore,  From each house we are getting 18 – 20kg cow dung.  From each house we are getting 900gm – 1 kg house waste.  From each house we are getting Corn stalk according to season From January to May (5 months) – Maize In Behea village total area 4500 Ekar, within this area 3000 Ekar is used for Maize. Now, 1 Ekar = 3 bigha 3000 Ekar = 3000 * 3 bigha = 9000 bigha From 1 bigha Field cultivation we are getting = 25 Quintals Maize (Approx) = 2500 kg (1 Quintal = 100kg) And from 1 kg Maize we are getting = 450 grms Corn stalk (Agricultural waste, after threshing the Maize) So from 2500 kg Maize we are getting = 2500*450 grms = 1125000 grms Corn stalk = 1125 kg Corn stalk Now, from 1 bigha we are getting 1125 kg Corn stalk = 1.125 ton Corn stalk Therefore from 9000 bigha we are getting = 9000*1.125 ton Corn stalk = 10125 ton Corn stalk From June to September (4 months) – Paddy
  13. 13. In Behea village we are getting Paddy 15 mon (Avg) from 1 bigha. Therefore, From total village we are getting = 15*9000 mon = 135000 mon = 135000*40 kg (we already know 1 mon = 40 kg) = 5400000 kg And From 100 kg Paddy we are getting 40 kg straw (after threshing the Paddy) Than, From 1 kg Paddy we are getting = 40/100 kg Straw So From 5400000 kg Paddy we are getting = 5400000*40/100 = 2160000 kg straw = 2160 ton straw From October to December (3 moths) – other cultivation on fields In this period mostly villagers are growing or Harvesting different crops like potatos, onions, garlic, carrot, reddish, ginger e.t.c as weather is suitable for these types of cultivations. (According to data collected from Behea village by door to door visit) In Behea village total no. of houses 1500 (approx) We are getting Raw materials of Biogas (Per day) – 1. Cow dung (1500*20) kg/day = 30000 kg/day = 30 ton/day (Avg) 2. House waste (1*1500) kg/day = 1500 kg/day = 1.5 ton /day (approx) 3. Paddy straw From June to September (4 months) We are getting Paddy straw = 2160 ton straw & we know 4 months = 4*30 days =120 days So we are getting Paddy straw = 2160/120 ton/day
  14. 14. = 18 ton/day = 18 ton/day (approx) 4. Corn stalk From January to May (5 months) We are getting Corn stalk = 10125 ton And 6 month = 6*30 days = 180 days So we are getting in these 6 months = 10125/180 ton/day = 56.25 ton/day Corn stalk = 56 ton/day Corn stalk Now, From January to May Total feed stalks (Cow dung, House waste, Corn stalk, Paddy straw) = (30 +1.5+56) ton/day = 87.5 ton/day = 88 ton/day (approx) BIOGAS 88 ton/day (feed stalks) ↑ —————————→ DIGESTOR —————→ Digested (waste) Total feed stalks = 88 ton/day Type Quantity Sp. Gas quantity Generated Gas (ton/day) (Normal m3/ton) (m3/day) 1.Cow dung 30 43 1290 2. House waste 1.5 270 405 3. Corn stalk 56 275 15400 Therefore total Generated Gas = (1290+405+15400) m3/day = 17095 m3/day Now from June to September Total feed stalks (Cow dung, House waste, Corn Stalk, Paddy straw) = (30 +1.5+12) ton/day
  15. 15. = 43.5 ton/day = 44 ton/day (approx) Type Quantity (ton/day) Sp. Gas quantity 3 (Normal m /ton) Generated Gas (m3/day) 1.Cow dung 30 43 1290 2. House waste 1.5 270 405 3. Paddy 12 277 3324 Therefore total Generated Gas = (1290+405+3324) m3/day = 5019 m3/day Now from October to December Total feed stalks (Cow dung, House waste, Corn Stalk, Paddy straw) = (30 + 1.5) ton/day = 31.5 ton/day = 32 ton/day approx Type Quantity Sp. Gas quantity Generated Gas (ton/day) (Normal m3/day) (m3/day) 1. Cow dung 30 43 1290 2. House waste 1.5 270 405 Therefore total Generated Gas = (1290+405) m3/day = 1695 m3/day From (1m3) Biogas we can get (2kWh) Electricity 1. From January to May 1 m3 Biogas = 2kWh Electricity : 17095 m3 Biogas = (17095*2) kWh/day = 34190 kWh/day Therefore per house will get 34190/1500 kWh/day = 22.797kWh/day = 23 kWh/day (Approx.) Now, 23kWh = 23000watt h = 15*60 watt*24 hour
  16. 16. Therefore, each house will get 15 no. of 60 watt bulb for 24 hours. Or 9 no. of 100 watt bulbs for 24 hours (Approx) 2. From June to September 1 m3 Biogas = 2kWh Electricity : 5019 m3 Biogas = (5019*2) kWh/day = 10038 kWh/day Therefore per house will get 10038/1500 kWh/day = 6.692 kWh/day = 7 kWh/day (Approx.) Now, 7kWh = 7000watt h = 4.8*60 watt*24 hour Therefore, each house will get 5 no. of 60 watt bulb for 24 hours. Or 3 no. of 100 watt bulbs for 24 hours (Approx) 3. From October to December 1 m3 Biogas = 2kWh Electricity : 1695 m3 Biogas = (1695*2) kWh/day = 3390 kWh/day Therefore per house will get 3390/1500 kWh/day = 2.26 kWh/day = 2 kWh/day (Approx.) Now, 2kWh =2000watt h = 1*60 watt*24 hour (Approx) Therefore, each house will get 1 no. of 60 watt bulb for 24 hours. Or may not be get because Efficiency of Electricity through Biogas is only about 90 %.
  17. 17. 4. Utilities 4.1 POTENTIAL The current availability of biomass in India is estimated at about 500 millions metric tones per year. Studies sponsored by the Ministry has estimated surplus biomass availability at about 120 – 150 million metric tones per annum covering agricultural and forestry residues corresponding to a potential of about 18,000 MW. This apart, about 5000 MW additional power could be generated through bagasse based cogeneration in the country’s 550 Sugar mills, if these sugar mills were to adopt technically and economically optimal levels of cogeneration for extracting power from the bagasse produced by them 4.2 TECHNOLOGY 4.2.1 Combustion The thermo chemical processes for conversion of biomass to useful products involve combustion, gasification or pyrolysis. The most commonly used route is combustion. The advantage is that the technology used is similar to that of a thermal plant based on coal, except for the boiler. The cycle used is the conventional ranking cycle with biomass being burnt in high pressure boiler to generate steam and operating a turbine with generated steam. The net power cycle efficiencies that can be achieved are about 23-25%. The exhaust of the steam turbine can either be fully condensed to produce power, or used partly or fully for another useful heating activity. The latter mode is called cogeneration. In India, cogeneration route finds application mainly in industries. 10MW Gaya Biomass Based Power Plant - Bihar - Construction Project
  18. 18. 4.2.2 Cogeneration In Sugar Mills Sugar industry has been traditionally practicing cogeneration by using bagasse as a fuel. With the advancement in the technology for generation and utilization of steam at high temperature and pressure, sugar industry can produce electricity and steam for their own requirements. It can also produce significant surplus electricity for sale to the grid using same quantity of bagasse. For example, if steam generation temperature/pressure is raised from 400oC/33 bar to 485oC/66 bar, more than 80 KWh of additional electricity can be produced for each ton of cane crushed. The sale of surplus power generated through optimum cogeneration would help a sugar mill to improve its viability, apart from adding to the power generation capacity of the country. 30 MW Bagasse Cogen project at a Sugar Mill in Bihar
  19. 19. 5. Instrument Needed for a Biomass Plant 5.1 Boilers A number of large manufacturers have established capabilities for manufacturing spreader stoker fired, traveling grate/dumping grate boilers; atmospheric pressure fluidized bed boilers and circulating fluidized bed boilers. Due to recent upsurge of interest in co-generation for surplus power, leading manufacturers are further upgrading their capabilities for high efficiency boilers. 5.2 Steam Turbines Almost all combinations – condensing, single extraction/double extraction condensing, back pressure, etc. are now being manufactured in the country with full after sales services. The efficiencies of turbines now being offered are comparable to the best in the world. 5.3 Gasifiers A gasifier is a piece of equipment that burns organic fuel in an oxygen-starved environment. This produces carbon monoxide, hydrogen and methane, and small amounts of other organic products. The carbon monoxide, hydrogen and methane are the main components that are subsequently oxidized as fuel to produce heat. Stokers can burn many types of fuels individually or in combination. Some operate similar to a gasifier with a deep bed of fuel on the grate. The bed can be burned in a low oxygen environment with undergrate air. Overfire air completes the combustion higher in the furnace. The advantage is a reserve of fuel in the boiler, ready to pick up an increase in steam demand. A rapid decrease in steam demand is attained by reducing undergrate air and fuel under controlled conditions. 5.4 Contaminants, Emissions Contaminants such as potassium, sodium, chlorides, silica and phosphorus can create havoc in a boiler without proper design and chemistry. Variation in fuel type, fuel quality, season and moisture will create operational issues. Sodium, potassium and phosphorus can cause slagging due to the reduction in the ash melting point. Chlorides from salts or plastics can cause corrosion, slagging and hydrogen chloride
  20. 20. emissions. Silica may cause slagging and erosion. Sulfur produces sulfur dioxide emissions, sulfur trioxide emissions and cold end corrosion. It is recommended to analyze the fuel ash for low fusion point and mix fuels or add materials such as lime to mitigate sticky ash. Sootblowers in specific boiler areas may be required to keep heat transfer surfaces clean. Where possible, contaminants should be removed from the fuel. How are emissions kept under control for sulfur oxides, NOx, carbon monoxide, volatile organic compounds, particulates and possibly other emissions? Sulfur dioxide can be reduced internally with lime addition in fluidized bed boilers and circulating fluidized bed boilers. Otherwise backend equipment is needed using lime in a wet scrubber, or a spray dryer absorber with a baghouse. 5.5 Unit Operations The above factors illustrate that biomass feed preparation is very important and forms an integral part of the briquetting process. The unit operations of the piston press and the screw press are similar except where the latest development in screw press technology has been adopted, i.e., where a preheating system has been incorporated to preheat the raw material for briquetting to give better performance commercially and economically to suit local conditions. In the present piston press operating briquetting plants, the biomass is briquetted after pre-processing the raw material but no preheating is carried out. Depending upon the type of biomass, three processes are generally required involving the following steps. A. Sieving - Drying - Preheating - Densification - Cooling - Packing B. Sieving - Crushing - Preheating - Densification - Cooling - Packing C. Drying - Crushing - Preheating - Densification - Cooling – Packing 5.6 Material Processing Equipment 5.6.1 Raw material storage All biomass feeds are relatively very light with bulk densities ranging from 0.05 to 0.18 g/cc (50 to 180 kg/m³). Because of their bulky nature these are normally stored in the open. Where the location lies in heavy rain fall region, these should be stored in ground level bins which can be covered by heavy waterproof sheets or alternative, a side open shed could be provided.
  21. 21. Depending upon the availability of supply, feed material for a 15 days to 3 months period should be stored at the plant site. It should be stored in a manner that the heaps are naturally aerated and heavy wind effects are minimised. About 3-4 sq. meter open space is needed to store one tonne of material. 5.6.2 Inclined screw feeder/Elevator The function of this screw is to feed the material from ground level to either the top feed end of a vibratory screen or the hammer mill.A standard enclosed screw conveyor or elevator made in M.S. is most suitable for this operation.It can be custom built by numerous vendors. It should preferably have variable speed so that.its capacity can be varied to match the capacity of related equipment. 5.6.3 Hammer mills Basically, hammer mills are bought out items and are supplied complete with a pneumatic conveying discharge cyclone, a blower and dust separators by many vendors. Most of these vendors have pilot plant facilities to test new materials and then recommend an appropriate machine complete with rpm and power ratings of the motor. Typical prices for hammer mill cum conveying systems of capacity 1500 kg/hr, as quoted by manufacturers in India complete with cyclone, blower and dust collector, range from Rs.3.5 to 6 lac per system. 5.6.4 Dryers & Flash Dryers All biomass materials are amenable to drying by flash driers with or without disintegration. Even though biomass materials are heat sensitive these can be satisfactorily dried at relatively high temperature because of short drying time. Most of the moisture is removed either in a disintegrater or at the entry point of the feed into the gas stream. Entry temperature of gases upto 300-400 °C can be conveniently employed even though the decomposition temperature of most biomass materials is between 250-350 °C. One precaution that must be taken is that sparks must not be allowed to proceed along with flue gases before gases are mixed with feed material. 5.6.5 Intermediate storage bin 5.6.6 Main distribution screw feeder 5.6.7 Return feeder
  22. 22. 5.6.8 Briquette Cutter To cut the briquettes to the desired length there are two technological options. One option is to provide an automatic circular cutter which will cut the hot extrudant into uniform lengths with smooth ends before these cut briquettes are allowed to fall on a cooling conveyor. 5.6.9 Cooling Conveyor 5.6.10Fumes Exhaust System 5.6.11 Preheater A preheater has become an important and integral component of the screw press briquetting technology for agro-residues like rice husk etc. Experience gained during testing has shown that the technology is feasible only with preheating of biomass. Therefore, it is imperative that the unit should be properly designed so as to obtain the desired heating result and a trouble-free and smooth operation. This section deals with the design parameters and operational aspects of this equipment. 5.6.12 Furnace Briquettes, along with some fresh raw biomass (mostly sieve oversized feed), are burnt along with air. A part of the heat produced is transferred to the preheaters and flue gases, in case required, are used for drying of feed in component . All the components require electrical energy inputs in order to carry out their operations but these inputs are not taken into consideration for a material and energy balance.
  23. 23. 6 COST ANALYSIS Electrical Power Input Power ratings of motors for 1.5 TPH of plant having two machines to produce 65 mm size briquettes from materials like rice husk, groundnut shells and cow dig are given in Table 6.2. Total power installed is 215 hp or 163 kW. With a utilization factor of 0.7, the power input into the plant is 114 kW. Assuming a 1.5 T/hr production rate, the electrical power input amounts to 76.2 kWh per tonne. However, during smooth briquetting operations, the die heaters are not in use for most of the time. Cost (Lakhs) One Two One One Motor Power Rating(hp) 2 50 15 2 One 3 1.00 One Two Two 2 6 114 1.00 2.00 24.00 One 3 2.00 Equipment Number Screw Feeder Hammer Mill Dryer Silo With Feeder Main Screw Conveyor Return Feeder Pre-heater Machines with heaters Cooling Conveyor Furnace Fluid System Fume Exhaust Auxiliaries One One One 15 5 2 15 219 0.50 4.00 4.00 2.00 1.25 3.00 0.75 45 TOTAL Assuming energy inputs for one tonne of briquettes having 4200 x 10³ Kcal of intrinsic energy as: Electrical = 76.2 kWh or 65,500 Kcal Thermal = 20 x 4200 = 84,000 Kcal The percentage of electrical energy input in briquetting = 1.5 in addition to thermal input = 2.0
  24. 24. Manpower Requirements Plant supervisor :One Shift technicians: Three (1 for each shift) Welder and maintenance technician: One Electrician: One Semi skilled machine operators :Three (1 in each shift) Labourers: For feeding raw material For storing briquettes Six (2 each shift) Six (2 each shift) Accountant cum store keeper One Typist/data operator One Watchman (optional) Casual labour Two (preferably resident) As and when required The above listed staff are only indicative and actual deployment will-depend on the specific location of the plant and degree of automation incorporated into the plant. For example, deployment of a small size loader would change the staffing pattern. If the feed is regularly produced by a main agro- industry, such as coffee curing or rice mills, a small feeding bin will eliminate the need for labourers feeding the raw material. All these functions have to be carefully considered in a project feasibility report and each report is highly site specific. 7.ECONOMIC ANALYSIS OF BRIQUETTING 7.1. Typical Cost Analysis A typical cost analysis with materials which are available in dry form and do not therefore require drying but do need grinding prior to briquetting is given below. The potential types of biomass under this category are rice husk, coffee husk and groundnut shells. Capacity Basis: Two machines each 750 kg/hr Production capacity = 1.5 T/hr (20 hrs/day operation) Operating days per year 300 Operating hours per year 6000 Capacity utilization 85% Raw material 8000 TPY Moisture losses 350 TPY Briquettes produced 7650 TPY Briquettes consumed (Dryer) 600 TPY Saleable production 7050 TPY
  25. 25. lnfrastructural facilities Power Land area Operational shed area Briquetting storage (covered area) 150 KW 3000 m² 240 m² 250 m² Investments Installed cost of plant & machinery (based on 9.0 lac for each machine) Land Building Total investment Working capital 52.0 3.0 4.2 59.2 7.5 Cost of production cost (Rs./tonne) Power Manpower Water Maintenance (including consumables) Administrative overheads Depreciation (Plant 10% Building 5%) Subtotal Financial cost 136.70 67.50 8.00 76.70 43.00 74.10 406.00 91.50 Cost of production 497.50 = Rs. 500/- per tone Overall cost of production per year Rs. 38.25 lac Profitability Basis: Cost of raw material = Net sale price of briquettes = Total sales (1450 x 7050) Production cost (500 x 7650) Raw material (500 x 8000) Gross profit before taxes Pay-back period Rs. 500/- per tonne Rs. 1450/- per tone Rs.(lac) 102.22 38.25 40.00 23.97 2.5 years
  26. 26. The above analysis is based on a screw press costing Rs.9.0 lat. Plants with less than two machines are not recommended. However, plants with more machines will definitely have better profitability and advantages of scale of operation can be derived. 8.CONCLUSIONS Bio-energy contribution to the total primary energy consumption in India is over 27%. Indeed, this is the case for many other countries, because biomass is used in a significant way in rural areas in many countries. However, the contribution of biomass to power production is much smaller than this - currently, biomass comprises only about 2650 MW of installed capacity, out of a total of about 172000 MW of total electricity installed capacity in the country (May 2011). India is the pioneer in biomass gasification based power production. While gasification as a technology has been prevalent elsewhere in the world, India pioneered the use of biomass gasification for power production. As a result, prominent Indian solution providers in biomass gasification are implementing their solutions in other parts of the world. It is however expected the biomass gasifiers and biogas units will be functioning at full technical potential by the time the project draws to a close in 2012. This will sufficiently increase the carbon emissions saved from biomass power and biogas in the project area. The activities arising as a result of the project have thus led to a positive impact on the environment. It is inevitable that the carbon mitigation potential of the project is much higher than is currently indicated. If all the indicators are working at their full technical potential and the local community is given full support, the carbon mitigation benefits of the projects will be significantly higher. The importance of monitoring annual CO2 benefits must also be highlighted as this provides an incentive to sustain use of the biogas units and power plants. Furthermore, is becomes crucial to set targets for the beginning and end of each year so as to promote sustainable use of resources.
  27. 27. 9. REFERENCES 1. Reed, T.B., Trefek, G, and Diaz, L., Biomass densification energy requirements in thermal conversion solid wastes and biomass, American Chemical Society 2. Google Search Engine 3. Power System J.B.Gupta 4. Industrial Biomass Energy Consumption and Electricity Net Generation by Industry 5. Website Of Government of India Ministry of New and Renewable Energy

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