Multi commodity solar tunnel Dryer (MCSTD)
The Philippine commonly practices sundrying techniques in drying fish products. However, the process is a largely dependent on the weather and is very difficult during the rainy season.
Moreover, the traditional method usually yields products with high microbial load. The exposure to wind and weather is a relatively slow process and results to a bigger losses through spoilage, lack of uniformity in the final product and development of undesirable flavor.
The studying practice of small-scale producers diminishes the quality of the commodities being dried. The practice allows dust, flies and microorganisms to contaminate the products. Aside from its health hazards, the poor quality dried products fail quality standards and are unacceptable for export. Worse, many small-scale processors cannot afford the operation coast of commercial mechanical dryers.
To help solve this problem, the MultiCommodity Solar Tunnel Dryers (MCSD) technology was adapted by PHilMech as a viable alternative to sundrying and use of commercial mechanical dryers. This dryer is a modified version of the solar tunnel dryer developed by the researchers of the Hohenheim University in Germany.
Cheaper in investment and operation cost than other available commercial mechanical dryers.
Dries commodities simultaneously, efficiently and hygienically
Preserves the quality of dried products longer because of lesser microbial contamination
Allows ready supply of processed food products even during lean months
Uses locally available materials to suit the needs of the farmers and fisherfolks engaged in processing
Easy to install/dismantle and maintain
Convenient to use
Gender friendly, can be used by women
Return of Investment (ROI)
Financial analysis revealed that if MCSTD is acquired through facility loan payable in 5 years at 14% annual interest rate, the enterprise will be profitable. The investment can be recovered within 4.15 years. An investment spread of 3.10% is realized when the discount rate (14%) is deducted from the calculated IRR. The net present value is still positive and the benefit cost ratio is slightly above the cut-off rate. The return of investment is 21.60%
The table below shows the financial analysis of using MCSTD acquired through facility loan.
|FINACILA INDICATORS||MCSTD acquired through facility loan|
|Payback period||4.15 years|
|Internal rate of return||15.92%|
|Net present value||30,300.95|
|Benefit cost ratio||1.06|
|Return of Investment||21.60%|
The PHilMech’s MCSTD has three major componenets: the heat collector, drying chamber and fan/blower.
The heat collector and drying chamber are covered with UV-stabilized polyethylene plastic sheets, mounted in inverted “V” metal frames. The floor is made of bended metal sheets with PEfoam insolation . The trays containing the products are placed on top of the ribbed drying flor.
A series of axial fan with electric motor forces air into the heat collector which increases the drying air temperature to 45 degrees Celsius to 60 degrees Celsius.
Parts of the MCSTD
A drying bed where the commodities are spread
A blower at one end where a burner may be installed for supplemental heating on rainy days.
Top plastic cover to trap the sun’s heat and protect the commodities from sudden rainfall, dust and insect.
The PhilMech’s MCSTD is fabricated using locally available construction materials. The modular design allows easy transport and installation in the processing areas.
Commodities: Banana, cassava, danggit, dilis camias, mushroom, tomato, espada, etc.
Heat collector and drying bed – bended metal sheet, G.I pipe and plastic sheet
Blower – 1.0 -1.25 m/sec . 22- v, single phase
Heat collector=L-7.3 m, w- 2 m
Drying bed = L-9.8 m , W 2 m
Axial fan = 88 watts , 220 v
Investment cost = 180,000 to 230 , 000
Aside from providing better quality dried products, the drying performance of MCSTD is significantly better than the traditional sundrying methods in terms of shorter drying time
|Product dried||Load (kg)||MCSTD (days)||Sundrying (days)|
Source: PhilMech pamphlet