This research developed a computer-based simulation model applicable for conventional and reversible airflow flatbed dryers, which can be used to predict the optimized time for mixing paddy (for the conventional flatbed dryer) and reversing the drying air (for the reversible air flatbed dryer). The developed software has the ability of simulating the paddy moisture content and temperature based on the input parameters of ambient (temperature and relative humidity) and drying air (temperature and airflow rate), dimensions of the dryers, and input grain properties and weight.
This paper reviews the utilization of rice straw in the world, including the production and properties of straw, different equipment for gathering and processing of straw, as related to costs in handling operations, various methods of using straw--from simple ways such as cattle feeding or organic fertilizers, to more sophisticated ways in electrical power generation or paper industry. Straw utilization in Vietnam is presented in parallel, with emphasis on identifying problems to be studied and verified versus other results in the world.
In the September of 2018, under the BMZ-funded IRRI Rice straw management project, the IRRI-Vietnam Office (IVO) coordinating with Tien Giang University, and HCMC Nong Lam University co-hosted a Field-demonstration of rice straw-based compost turner and a Write-shop on outlining a bookentitled "Sustainable rice straw management", in Tan Phuoc district and My Tho city of Tien Giang province, respectively.
The research paper entitled, "IMPLEMENTATION OF A SOLAR-ASSISTED DRYER FOR FISH", was submitted, reviewed, and accepted for publication and presentation at the International Conference on Agricultural and Bio-system Engineering (ICABE) 2017, Nong Lam University, Ho Chi Minh City, Vietnam.
Recently, the Daknong Agricultural Extension Center of the Daknong Department of Agriculture and Rural Development invited Center for Agricultural Energy and Machinery of the Nong Lam University - Ho Chi Minh City (NLU), to co-host the training courses at the districts and town of the Daknong province in this early September. The training courses are belonging to the national agricultural extension program in the year of 2018.
In the last August of 2018, The CENTER FOR AGRICULTURAL ENERGY AND MACHINERY of the HCMC Nong Lam University fabricated, installed, and transferred one pepper dryer (SRA-2, drying air-reversal type, with 2-ton/batch capacity) to Cambodia. The dryer was set up for a pepper farmer in Kampot province, Cambodia.
An applied research regarding to management and use of rice straw more effectively was done by a research team of the NLU Center for Agricultural Energy and Machinery coordinating with other institutions such as Tien Giang University, Binh Minh Group, and the International Rice Research Institute (IRRI). This research belongs to the BMZ-funded IRRI rice straw Management Project that is being conducted consurrently in Vietnam and other Southest Asia countries. Results of the research were summarized into a scientific paper, was sent for reviewing and then accepted for publishing on the Scientific Journal of the Technical University of Dresden (Germany).
The study was conducted with the aim of evaluating the effectiveness of drying the coffee bean as applying two-stage drying method that was combining a fluidized-bed dryer with a recirculating columnar dryer.
Recently, coordinating with Center for product-quality management of the Loc Troi Group, the NLU Center for Agricultural Energy and Machinery composed a document and taught at the training course on "Postharvest Mechanization in Rice Seed Production". The training course was being taken place in 3 days, at Dinh Thanh Agricultural Research Center, Dinh Thanh commune, Thoai Son district, An Giang province.
The training course “Technologies of postharvest agro-product storage" was organized by Binh Thuan Center for Agricultural and Fishery Extension in 3 days from August 30 to September 01, 2017. The host of the training course was Dr. Nguyen Thanh Nghi, Director of the NLU Center for Agricultural Energy and Machinery.
In April 2017, the NLU Center for Agricultural Energy and Machinery coordinating with Vietnamese farmer Association - Dak-Nong Branch hosted the training courses for farmers at 8 districts and towns of Dak-Nong province.
In Vietnam, pepper is mainly planted in Gia Lai, Dak Lak, Dak Nong, Binh Phuoc, Dong Nai and Ba Ria–Vung Tau Provinces. Total pepper cultivated area is about 51,000 hectares with production of 160,000 tons in 2016.
The Rice Straw Management Project funded by BMZ (Germany) through the International Rice Research Institute entitled “Scalable straw management options for improved livelihoods, sustainability, and low environmental footprint in rice-based production systems” was deployed concurrently in 3 countries: Cambodia, Philippines, and Vietnam, from the middle of 2016.
Within the framework of the IRRI - BMZ rice straw management project entitled: Scalable straw management options for sustainability and low environmental footprint in rice-based production systems, the International Rice Research Institute (IRRI) coordinating with the Don Bosco vocational school, and the Center for Agricultural Energy and Machinery (CAEM) of the Nong Lam University co-hosted the seminar and demonstration on straw baler in Battambang province of Cambodia, on 30 April, 2016.
Application of improper methods on rice processing affects rice quality and head rice recovery. In Vietnam, paddy with different moisture contents (from 13% to 17%) is dehusked by both rubber roll and stone disk. Thus, objective of this research was to evaluate the technical and economic aspects of the two methods. Optimization was conducted with 20 experiments for input factors (moisture content) and output factors (head brown rice recovery, specific energy consumption).
Although the windmill has been used for water pumping for many centuries, its development and application is limited due to high investment cost. Using windmill instead of diesel engine to drive a water pump reduces dependence on fossil fuel and mitigates greenhouse gas emissions. Thus, this study was conducted to optimize water use from a windpump coupled to a drip irrigation system. Performance of the windpump-drip irrigation system was also evaluated based on technical and economic feasibility. Water from the windmill combined with suction pump and piston pump was applied to vegetable crops in a 0.18-ha area through a drip irrigation system. Results showed that average daily discharge of the windpump was 9.2 m3/day (24 hours) at 1.6 m/s daily wind speed. It varied from 0.7 at 1.6 m/s to 22.1 m3/day at 2.7 m/s. Overall efficiency of the windmill-suction pump system varied from 23.1 to 6.1% corresponding to wind speed of 1.7 to 4.3 m/s, respectively. With total available water supply from the windpump and rainfall of 17.1 m3/day, optimum service area of the system would be 0.81 ha, 0.95 ha, 0.65 ha, and 0.32 ha for tomato, eggplant, onion, and rice crops, respectively. Economic analysis showed that with three tomato crops per year in 0.81 ha, annual net income would be PhP38,960. Financial rate of return was 19% with a payback period of 9 years. Thus, the investment for the windpump-drip irrigation system would be feasible only for high-value crops.
Key words: drip irrigation, high-value crops, optimized water utilization, windpump.
The study was conducted by researchers of the Research Center for Agricultural Energy and Machinery (CAEM) of the Ho Chi Minh City Nong Lam University (NLU) with the objectives of researching on drying ways for cassava and of evaluating the adaptability of the reversible-airflow dryers in drying of cassava.
On the days of 01 and 02, March 2016, Nong Lam University (presided by CAEM) coordinating with National Agricultural Extension Center hosted the demonstration of rice straw balers, and the workshop on "Technologies and equipment for gathering and treatment of rice straw, in the Mekong Delta region of Vietnam", at Cuu Long Rice Research Institute, Thoi Lai district, Can Tho city.
Rice straw is a rice by-product, which is currently mostly wasted in Vietnam, in particular in the Mekong delta. At present, the cost of straw gathering is increasing because of the increased use of combine harvesters. High labor cost and lack of labor makes manual collection unfeasible. Farmers therefore often just burn it, which causes pollution, increased greenhouse gas emissions and loss of opportunities to value add. An economic and environmental evaluation and technical field testing of a straw baler with 4 ha/day capacity was therefore conducted in Long An province. During the field testing data on the gathering capacity, fuel consumption, labor requirement and other cost items were collected. The test results showed that the baling cost is US$19.0 per ton of rice straw, the pay-back period of 2.1 years and the internal rate of return of 38%. In addition to the baling cost, the transportation cost varies from US$24 for a distance of 100 km to US$32 for 150 km. The benefits of the machine are not only economical but also include the reduction of field burning. Key words: Rice straw gathering, technical and economic evaluation, environmental benefits.
In order to meet demands of mechanization and automation more and more increasing, the NLU CAEM researched, designed, fabricated, and applied automatic rice husk furnaces into the productionto be used for its agro-product dryers such as SRA dryers, recirculating dryers, fluidized-bed dryers, etc.
In November 2013, the NLU Center for Agricultural Energy and Machinery designed, fabricated, and installed sucessfully a SRA dryer for SOYBEAN, with capacity of 20 tons/batch, at the Xa Mat, Tan Lap commune, Tan Bien district, Tay Ninh province, for GREEN LIFE Ltd. Company (in HCM).
In the last May of 2013, the NLU_CAEM cooperated with Ly tuong Ideal Farm Joint Stock Corporation (HCMC), and Duc Thanh machinery company (Dong Thap province) designed, fabricated, and transferred a 10-ton/h fluidized-bed dryer to Kilombero Plantations LTD., Tanzania (Africa).
The seminars on Energy-saved drying technologies and equipment were held in Xuan Loc district and Long Khanh town of Dong Nai province in 2012. This activity was the collaboration between the Dong Nai Agricultural Extension Center and the NLU Center for Agricultural Energy and Machinery.