عنوان

Analysis of two commercial rice-drying systems under Malaysian conditions

Number

TLpq303891730

.Language of Text, Soundtrack etc

انگلیسی

Title Proper

Analysis of two commercial rice-drying systems under Malaysian conditions

General Material Designation

[Thesis]

First Statement of Responsibility

H. B. M. Salleh

Name of Publisher, Distributor, etc.

Michigan State University

Date of Publication, Distribution, etc.

1990

Specific Material Designation and Extent of Item

221

Dissertation or thesis details and type of degree

Ph.D.

Body granting the degree

Michigan State University

Text preceding or following the note

1990

Text of Note

A perennial problem of the Malaysian rice industry is the inadequate drying capacity of the dryers for properly handling bumper harvests and very wet grain at the private and public rice mills. The concurrentflow (CCF) dryer and the in-bin counterflow (IBCF) dryer, both used at commercial elevators in the U.S., were evaluated for application in Malaysia. Field experiments were conducted with the multi-stage concurrentflow dryer and with the in-bin counterflow dryer. The Michigan State University (MSU) concurrentflow and in-bin counterflow drying models were validated with the experimental data. The drying of rice under Malaysian conditions in both dryers is simulated using the appropriate MSU simulation models. In drying rice in Malaysia from 23% to 13.5% (without cooling) in three passes (i.e. 23-19%, 19-16%, and 16-13.5%), under optimum grain-quality conditions, the three-stage concurrentflow and in-bin counterflow dryers have drying capacities of 1.023 and 0.026 t/m2/h, respectively. The predicted energy efficiency is 3861 kJ/kg for the concurrentflow dryer and 6408 kJ/kg for the in-bin counterflow dryer; the maximum inlet air temperatures are 126.7C and 47.2C for the two dryers, respectively. Eight drying systems are proposed for Malaysia to serve 3,000 ha of rice production; double cropping is practiced. A life-cycle costing program was used to evaluate the savings of the systems compared to custom-drying the wet rice at the locally charged price. Each drying system shows a positive cash flow every year over the 11 years of the systems' lifespans. The IBCF36/1 system (i.e. five 36ft (10.97m) diameter in-bin counterflow dryers located at one site) generates the maximum after-tax total savings, followed by the CCF12/1 system (i.e. one 12ft (3.66)m x 12ft (3.66m) three-stage concurrentflow dryer located at one site). The IBCF18/20 system (i.e. twenty 18ft (5.48m) diameter in-bin counterflow dryers located at twenty separate sites) has the lowest savings compared to custom-drying. On the whole, centralized drying systems cost less, and hence have higher after-tax total savings than decentralized systems. A multi-stage concurrentflow dryer offers efficient drying and has the least space requirement. However, it demands extensive technical expertise to operate effectively, a definite disadvantage in Malaysia. In conclusion, it is recommended that for technical as well as economical reasons, the in-bin counterflow dryer is the rice dryer of choice in the 1990s for rice-milling plants in Malaysia.

Agricultural engineering

Applied sciences

Biological sciences

Food science

H. B. M. Salleh

Electronic name

p

[Thesis]

276903

a

Y