Tray-Paddy Dryer for Small Scale Farmers in the PhilippinesDann A. Peamante, Joey Jay Lacap and Rex R. Serrano Don Bosco Technical College Mechanical Engineering Department
BACKGROUND OF THE STUDYRice is the most basic crop in the Philippines [8]. According to the Post Harvest Profile of paddy, the Philippines contribute 2.07 percent in the world rice production. Paddy drying is one of the critical post-harvesting processes in rice production. It is the process of reducing moisture in order to ensure the quality of the paddy during storage. Wet paddy has more tendencies to suffer from insect infestation, yellowing, loss of freshness, and lack of quality [12]. As a result, wet or improperly dried paddy has relatively lower price. By far, sun drying is the most common and most practical means of paddy drying[5]. However, it presents several disadvantages such as insects and birds infestation, no control over drying temperature, contamination, etc. Also, in the Philippines, some places have longer wet seasons; 60% of the year is rainy. During rainy seasons, many farmers are forced to sell their wet paddy for a lower price, about 2 to 5 pesos per kilogram difference in the price of wet and dry paddy [7]. All existing mechanical dryers are based on large capacities to be economically viable. Small-scale dryers are yet to be developed and studied.
OBJECTIVESThe study intends to: y Develop a small scale tray-type paddy drier using rice husk gasifier Specifically, the study aims to: y Design a mechanical dryer that: o Dries paddy up to 18% moisture content in the first stage of paddy drying o Dry 500 kg of paddy in one day y Fabricate and install the dryer with: o A maximum of fabrication and installation cost of P15,000.00 y Evaluate the technical performance of the paddy dryer y Assessment of the economical viability of the paddy dryer y Perform an environmental impact assessment of the dryer
SIGNIFICANCE OF THE STUDYTechnical: Drying is the most crucial part of post-harvest process. Improper and delayed drying would cause deterioration of the paddy quality. No existing mechanical dryer is designed on a small scale basis. The project will be beneficial for farmers that have low production rate. Economic: In the Philippines, 90% of small scale farmers rely on heat of the sun for drying their crops. However; sun drying is not reliable since the weather is unpredictable. Furthermore; some regions in our country have longer rainy seasons.If the drying process is improperly done or delayed, deterioration of the paddy quality will occur. As a result, the value of the paddy decreases. Environment: The fuel used in the dryer system is a by-product of rice. The utilization of this by-product aids the solid waste management.
METHODOLOGY1. Design SYSTEM DIAGRAM
a. A tray dryer will be design based on the production capacity of the small scale which averages 400 kg to 500 kg of paddy.
b. A cross-draft Gasifier will be designed. The size of the reactor, intake, and exhaust and other parameters will depend on the drying rate of the tray dryer.
A heat exchanger and a blower are necessary to heat the ambient air and deliver it to the tray dryer. The dimentions of the heat exchanger will be based on the heat that the gasifier transmits while the capacity of the blower will be based on the drying rate. 2. Fabrication a. The gasifier will be the first component to be fabricated since the temperature it produces will determine the size of the heat exchanger. The outer part of the reactor will be made of Galvanized Iron(GI) sheet gauge no. 18 while the inner reactor will be composed of Stainless Steel sheet gauge no. 20. b. The tray dryer will be composed of 15 trays made GI sheet gauge no. 24. Mild Steel will be used for the support and the frame of each tray. c. The heat exchanger and the stack will be composed of GI sheet gauge no. 24. 3. Installation Each component will be assembled by using GI sheet gauge no. 24. After installation, the area and the volume which will the system cover will be determined. 4. Testing a. Laboratory Testing will be done inside the campus. This is to obtain the settings that will yield the optimum result. c.
b. Field Testing will be done twice to determine the actual performance of the system. Testing will be done on both the north and south area of the country; one for each area. 5. Evaluation a. A moisture meter will be used to determine the moisture content (MC) of the paddy. This is to assess whether the dryer is capable of drying up to 18% MC. b. An evaluation will be done to determine if the system is economically viable. c. An Environmental Impact Assesment Study (EIAS) will be done to determine the environmental effects of the dryer.
COSTINGGasifier Galvanized iron sheet, no. 20 or 18 Stainless steel sheet no. 20 or GI sheet no. 16 Stainless steel rod, 1/4-in. diameter Stainless steel screen mesh, 1/4 in. Hinges Door Lock Fan or blower Switch Estimated Cost Php 3,000.00 Tray Dryer Galvanized iron sheet, no. 24 Flat bar (Mild Steel) Support (Mild Steel) Wedge (Mild Steel) Hinges Estimated Cost Php 8,000.00 Heat exchanger and stack Galvanized iron sheet, no. 24 Estimated Cost Php 2,000.00 Total Estimated Cost Php 13,000.00 - 1 piece - 1 piece - 1 piece -1 piece - 2 pieces - 1 piece - 1 piece - 1 piece
- 8 pieces
- 4 pieces
- 4 pieces
REFERENCES[1] A Chupungco, E. Dumayas and J. Mullen. Two-stage grain drying in the Philippines. Philippines: ACIAR, 2008. [2] A Rajvanshi. Biomass Gasification . India: Phaltan, 2005. [3] B. Tadeo. Rice Biomass for Agriculture & Industry in the Philippines & ASEAN. Philippines: PhilRice, 2006. [4] de Padua D.B. 2007. Status of rice postharvest industry in the Philippines. Presented at ARF annual rice forum 2007 and NAST roundtable discussion on PA 2020, Protecting the rice farmers harvest: the way forward , 23 November 2007, Traders Hotel, Manila. [5] Elepano A.R. 2008. Roundtable discussion on food security with focus on rice: postproduction issues. Presented at the roundtable discussion on food security with focus on rice, 21 April 2008, University of the Philippines at Los Banos, College, Laguna. [6] G. Srzednicki PhD and R. H. Driscoll PhD. Implementation of a Two-stage Drying Systemfor Grain in Asia. Australia: International Union of Food Science & Technology, 2008. [ 7] Hughes P. and Daglish G. 2005. Information, knowledge and training gaps in the post harvest sector of the Philippines grain industry: ACIAR Project ASEM/2005/017. [8] IRRI. Paddy Drying Systems, 2004. [9] K. Nuortimo. A CASE STUDY OF THE ECONOMY OF BIOMASS COCOMBUSTION USING FLUIDIZED BED TECHNOLOGY [10] K. Sivakumar and N. Krishna Mohan. Performance analysis of downdraft gasifier for agriwaste [11] Mendoza E. and Quitco R. 1984. Quality deterioration and value loss in grain. Pp. 15 20 in Coming to grips with the wet season grain handling problems in Southeast Asia. ASEAN Crops Post Harvest Programme: Manila. [12] M Gummert and J Rickman. Paddy Drying Systems. IRRI, 2005. [13] R. Stahl and E. Henrich. Definition of a Standard Biomass. Gernany: RENEW, 2004 Biomass Materials. [14] S. Wetchacama, S. Soponronnarit, and W. Jariyatontivait. Development of a Commercial Vibro-Fluidized Bed Paddy Dryer. Thailand, 2000.
