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1 THE 28 TH CONFERENCE OF THE FEDERATION OF ENGINEERING ORGANIZATIONS CAFEO 28 HANOI VIETNAM, 30 TH NOV. - 2 ND DEC., 2010 TITLE: Preliminary results in research and technology transfer of by-product utilization for higher income and lower CO2 emission YOUR PHOTO (or you can attach a separate file for photo) AUTHOR(S)’ NAME(S): Nguyen Quoc Viet, Chu Van Thien, , Dau The Nhu, Do Ngoc Huyen, Trinh Van Trai, Nguyen Thi Lan Huong ORGANIZATION & DESIGNATION: Vietnam Institute of Agricultural Engineering & Post- Harvest Technology ADDRESS: 126 Trung Kinh, Cau Giay, Hanoi TEL: + 844 3868 7884 FAX: + 844 3868 9131 EMAIL: viaep2004@yahoo.com Preliminary results in research and technology transfer toward by-product utilization for higher income and lower CO2 emission Nguyen Quoc Viet * , Chu Van Thien, Dau The Nhu, Do Ngoc Huyen, Trinh Van Trai, Nguyen Thi Lan Huong Vietnam Institute of Agricultural Engineering and Post-Harvest Technology (VIAEP) Abstract Vietnam has an abundant source of by-products from agricultural production activities like rice straw, stubble, hush, sawdust, baggase, coffe pulp, cashew apple and nut shell, etc. These by- products are mostly burned, discarded as ash or rubbish, even poured to rivers causing economical waste and environmental pollution. Facing to the situtation, during last four years Vietnam Institute of Agricultural Engineering and Post Harvest Technology has conducted some bellow studies for the utilization of agro by-products and obtained highly applicable results: (i) Fluidized bed combustion technology burning by-products to supply energy for drying agro- products (ii) Technonogy and equipments for gathering, preservation and processing of rice straw (iii) Appropriate technology and equipments for production of particleboard from rice straw and short fibre of coconut shell (iv) Production of fermented coffee pulp at industrial scale to provide suplemental feed for animal husbandry Technologies and equipments from the the studies are being transfered succesfully to manufacturers and farmers. Key words: forest, agro by-products, utilization, fluidized bed combustion, rice straw, husk, coffee pulp, particleboard, (*) Corresponding author: Tel: +84438687884, E-mail: quoc5viet5@yahoo.com , Add: VIAEP, 126 Trung Kinh str., Cau Giay dist., Hanoi, Vietnam 2 I. INTRODUCTION In Vietnam, the agricultural sector is the main source of income for the majority of people and its future performance will continue to be the main factor influencing the living standards of Vietnamese (Ogle & Phuc 1997). Agro and forest by-products coming from activities of forest and agricultural processing and production are available locally in large amounts. Rice straw and husk: Rice is the predominant food grain with 2-3 crops per year in Vietnam with yield of 38 million tons (2008). Rice straw and husk produced every year is plentiful. According to a case study carried out in the countryside of Hanoi on 5 rice varieties (Nguyen Xuan Trach, unpublished data), on the average 0.83 kg straw and around 0.2 kg of husk is produced together with each kilogram of paddy grains. Based on these figures, 25-30 million tonnes of straw and above 7 million tons of husk could be expected every year now in Vietnam. Vast amounts of this renewable resource are burnt either in the field or as cooking fuel. Some is used for other purposes such as litter, mushroom production, etc. Coir dust and short fibre of coconut shell: Coconut palms are cultivated mainly in Ben Tre and Tra Vinh provinces with a total area of 48,000 ha (Nien giam thong ke, 2005) producing 254 million coconuts. For a ripened coconut, the shell takes 33-35% in which coir dust and short fiber take 70%. If average weight of coconut is 1.6 kg/fruit, there would be hundred thousands of tons of coir dust and short fible of coconut shell. Coir dust is often used used as supporter for seedling or to make clean clay. Short fibre has not been utlized for any other purposes, it is discarded causing water and air pollution. Coffe pulp: Annually, average productivity of fresh coffee bean in Vietnam is estimated around 850,000 tons/year and accompanied coffee by-product amount is around 340,000-350,000 tons/year. Coffee pulp accounts for 40% weight of coffee fruitt. Coffee pulp containing high content of moisture (80-85%), proteins, carbonhydate, vitamins, mineral elements provides good environment for microbial development (Juan, 2002). Coffee pulp also contains anti-nutritional substances like caffeine and tannin making it difficult to be used in animal feed. The by-product is usually untreated before discarded causing serious pollution problems in the air, land and water source. Current trends towards sustainable agriculture under protection of the environment may highlight the need to improve utilisation of agro and forest by-products. Additionally, utilisation of forest and agro by-products provides more job oppotunities, not only ecological but also economic efficiency, reduces the natural resource exploitation, etc. In the reality, studies to find out scientific and technological solutions for better utilisation of the vast amount of such renewable sources in Vietnam are definitely neccessary and urgent. Since last five years, Vietnam Institute of Agricultural Engineering and Post-Harvest Technology (VIAEP) has paid much attention in technology research and transfer towards utilization of forest and agro by-products for better economic and ecological efficiency. II. SOME RESULTS OF TECHNOLOGY RESEARCH AND TRANSFER TOWARDS UTILIZATION OF FORESTRY AND AGRO BY-PRODUCTS 1. Fluidized bed combustion technology burning agro by-products to supply heat for drying and processing of agro products Fluidized bed combustion system (FBC) has been succesfully studied on its structure and technical parameters for burning agricultural residues like rice straw, coffee husk, sawdust. This is the first FBC in Vietnam that is designed and used to burn by-products and release heat for drying some agro-products such as rice, maise, coffee, fruits and vegetables. Additionally, FCB burning by- 3 products is also used to supply heat for drying wood, constructional materials; supply ash for cement production. Main technical parameters of the FBC was established as follows: - Input (rice straw, coffee husk, sawdusk): 50-70 kg/h - Size: 0,465 x 0,465 m - Height of burning space: 1,656 m - Caloriphere: 43 pipes - Fan: 600 m3/h, pressure H=700 mm H2O Operation of FBC is illustrated in Figure 1. Agricultural residues are burnt in burning chamber (5). High pressure fan (3) and suction fan (9) lead to presure change in the chamber to make sand boiling. Gas for burning is supplied by high pressure fan (3) in primary and secondary flows. Primary gas flow is suplied through pipes. Secondary gas flow is supplied above the sand layer to get more oxygen for better burning. Burning chamber connects with an auxiliary deposit chamber (6). Ash deposit is separated to the deposit chamber and heated gas flow goes to heat exchange equipment to transmit heat to the air which afterward acts as the drying agent in the drying chamber. Economic and social efficiency of using FBC: Application of FBC for 7 ton/batch dryers lowered total cost 70% compared to coal burning system. In details, cost of FBC system for the mentioned dryer to was 13,800 VND/hour while total cost of coal burning system for the dryer was 43,800 VND/hour. Technology transfer: FBC systems have been transfered into production and in good operation: - 4 systems burning rice straw and coffee husk release heat to dry rice, coffee, maise and cassava waste, capacity 60 and 120 kg/h of agicultural residues , in Gia Lai coffee company and N&N company in Gia Lai, Son La and Ha Tay provinces - 3 systems burning rice straw to release heat and ash for high quality cement production, capacity: 600, 1200, 1500 kg/h. The systems replace FO burning oven in Holcim company, Hochiminh city (Fig. 2) 7 2. Vít tải cấp liệu 4. Van điều chỉnh 6. Buồng lắng bụi 8. cyclon lắng bụi 1. si lô chứa liệu 1 3. Quạt lò 2 34 56 5. Buồng đốt 7. calorife 9. quạt hút Tác nhân sấy không khí 8 9 Fig.1. Operation schema of a FBC system 1. MATERIAL STORAGE SILO 2. MATERIAL FEEDING SCREW 3. OVEN FAN 4. ADJUSTING SCREW 5. BURNING CHAMBER 6. DUST TRAPPING TANK 7. CALORIPHERE 8. TRAPPING CYCLON 9. SUCTION FAN 4 Fig. 2. FBC burning rice straw installed in Holcim cement company, Hochiminh city; Capacity: 600; 1200 và 1500 kg/h 2. Technology and equipment system for gathering, storage and processing of rice straw for better utilization Rice straw is a by-product available in a significant quantity in rice production. Rice straw is a good source to produce various products like organic fertilizer, animal feed, material for paper production, etc. In Vietnam, utilization of rice straw is not yet paid attention and in spontaneous approach. Rice straw in the field is gathered by human labor. The amount of gathered straw is inconsiderable. Most of rice straw is burnt in the field or self-degraded causing environment pollution. Facing with the practical situation, demands of technology and equipment system at industrial scale for gathering, packing, storage and processing of rice straw is much neccessary and urgent to give more comprehensive measures, increase economical and social efficiency, contribute to agricultural and rural industrilization as well. The governmental project titled: Study on technology and equipment system for gathering, storage and processing of rice straw for better utilization, coded KC.07.10/06-10, has been managed and implemented in VIAEP. Some achievements of the project are as follows: - Technological processes: mechanization processe for rice straw gathering and packing, process for rice straw and stubble storage, process for processing of rice straw based animal feed by applying urea (ammoniation) and microbial fermentation, process for animal feed production - Technical drawing and equipment systems: o Gathering and packing machine connected with a tractor (rice straw in round shape package and square shape package); o Supplying and quantifying equipment for rice straw packing machine; rice straw and stuble chopping machines to make green manure o Rice straw storage and procesing equipements to make animal feed: packed rice straw chopper, mixer TMR, feed packing machines 5 - 01 model of gathering, storage and processing of rice straw to make animal feed in Red River Delta at scale of 20 ha, 0.15 – 0.2 ton/hour; 01 model of gathering, storage and processing of rice straw to make animal feed in Cuu Long River Delta. Fig. 3. Schema of gathering dried rice straw in one- stage rice harvesting technology Fig. 4. Schema of gathering fresh rice straw in one- stage rice harvesting technology Fig. 5. Schema of gathering dried rice straw in multi-stage rice harvesting technology Fig. 6. Schema of gathering fresh rice straw in multi-stage rice harvesting technology Packing in the field Transport to storage Rice straw in the field gathered by combined harvested Dry under sunlight to moisture 16- 20 % (3-5 days) Drying untill moisture content 16 -20% (3-5 days) Forming straw bed Rice straw from rice combined harvester (piled rice straw) Spreading straw, layer 100-300 mm Packing Transport to storage Packing Covering Rice straw from rice combined harvester (piled rice straw) Transport to storage Fermenting factor Covering the packed straw Transport to storage Rice straw in the field gathered by combined harvested Packing in the field Fermenting factors 6 3. Appropriate technology and equipments for production of particleboard from rice straw and short fibre of coconut shell Rice husk and short fiber of coconut shell account for the biggest proportion of agro by-products in Mekong River Delta, Vietnam. Many studies have been carried out to utlise these by-products to make more valuable commodities like beton, cement board, firewood, electric generation, etc. Little become feasible. Utilisation of rice husk and short fibre to make particleboard is a new trend recently. These are new materials for producing particleboard, the research team concentrated to study how to treat the materials and the particleboard production process. They also studied to design and manufacture a grinding machine, a drying machine and a spreading machine to fulfill existing machinery line of producing particleboard from wooden shavings to make a machinery line of producing particleboard from rice husk and short fiber of coconut shell. The research result showd that: - Particleboards made from 100% untreated rice husk meet standards of agricultural sector (04TCN-1999). The particleboards made from 100% rice husk treated by natri hydroxide may reach the standard but need more 50% of glue and more cost (plus 20,000 VND) compared to particle board made from wooden shavings foreach the same size board. - Particleboards that meet standards for making furniture were made from conditions: mixing untreated rice husk with short fiber in a ratio of 6:4, then glue was added at 15% in surface layer, 12% for middle layer; pressed at 20 kG/cm 2 ; 150 0 C in 17 minutes. - Machines were designed and manufactured including a grinding machine, a drying machine and a spreading machine. The machines were used to fulfill machinery line of producing particleboard from wooden shavings to make a 300 boards/day machinery line of producing particleboard from rice husk and short fiber. The spreading machine is very simple and effective. Economica and social efficiency: Production of particleboards from rice husk and short fiber of coconut shell achieves no much economy efficiency because the particles are too small size so they to need more glue compared to particleboards made from wooden shavings. However, the produces possess desired properties such as thermo-resistant, burnt-resistant, scratch-resistant and environmentally friendly. It is recommended that particleboards should be made for builing. Technology transfer: Technology for production of particleboard from rice husk has been applied in Pham Duc Company Ltd. (producer of particleboard from wooden shaving), Hiep Nguyen Company Ltd., Kien An village, An Dien commune, Ben Cat district, Binh Duong province. 4. Production of fermented coffee pulp for use in feed at industrial scale Average yield of fresh coffe in Vietnam is around 850 000 tan/year and the by-product from coffee nut processing is 340,000 – 350,000 tons/year. A small part of coffee pulp amount is processed in to microbial organic fertilizer, the remaining part is often burnt. Meanwhile, demand for animal feed is increasing, estimated around 16-17 tons/year (Vang, 2003). Project titled Pilot production of fermented coffee pulp for use in animal feed was conducted succesfully at industrial scale. Some main results of the project as bellow: - Complete technology scheme of coffee pulp fermentation for production of probio and prebio preparations. In which, prebio preparation is supplemented in feed for pig, cow, chicken and probio preparation is supplemented in feed for fish. - Equipment system for production of fermented coffee pulp (FCP) at scale of 5 tons/day ; 1200 tons of fermented coffee pulp meeting standards and quality requirements to use in feed for cattle, poultry, fresh water fish. The high quality equipment system has been established in Eapok Coffee Company. 7 - Experiment of supplement of FCP (prebio) in feed showed that feed cost was decreased by 9.9- 11.0% /10 eggs when add 5-15 % FCP for chicken, 12.2-20,0%/kg when add 15-20 % FCP for pig, 18-29 %/kg when add 20-30% FCP for cow. FCP (probio) also improved water quality when used for fish. - Technological scheme and operation of equipment line for FCP production are running stably, showing high feasibility and applicability in Tay Nguyen. Economic and social efficiency of the project: Increase income for coffee enterprises, provide a nutrional feed source for animal husbandry, and reduce environment pollution. Application of FCP: FCP are using in cow farm of Eapok Coffe Company; Eatam Fish Farm in Dak Lak. II. CONCLUSIONS AND RECOMMENDATIONS Conclusions Research and transfer of technologies from the mentioned projects gained some considerable achievements, opening the new measures for utilization of forest and agro by-products. The achivements contribute to improve economic and ecological efficiency of forest and agricultural production: reduce environment pollution, create more job oppotunies and higher income, supply energy for production, etc. However, the application and development of the technologies in organizations and regions are still limited. Recomendations - To establish strategies of science and technology development and application in utilization of forest and agro by-products in accordance with Vietnam conditions. - To foster support, encouragement, and investment in research and transfer of technology: strenthening human capacity, adopt advanced technologies of reducing cost in biomass accumulation and transportation, improve facilitate structures, support capital and reduce tax for - To establish connections of scientiest, producers, and educators inside the country; enhance international cooperations and exchange to approach to economically and environmentally efficient and advance models. - To increase the awareness of utilization of by-products for users and farmers; minimize the traditional use of forest and agro by-products (burning into ash, pouring to water, discard and let by-products be self-degraged, etc.) REFERENCES Juan, B.U.Rojas. 2002. Use of coffee pulp as feed ingredient for Tilapia culture. PhD. Thesis, Nguyen Dang Vang. 2003. Production of animal feed in Vietnam period 2000-2010. Report of National Institute of Animal Husbandry,. Nien giam thong ke. 2005 . Statistical Publishing House Ogle B and Bui Huy Nhu Phuc. 1997 Sustainable intensive livestock-based systems in Vietnam. IRDC Currents. Volume 13: 16-22.