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This article studies the possibility of reducing the high initial moisture content of wet rough rice using a small-scale low-cost pneumatic conveying dryer as a first stage dryer. The parameters investigated are final moisture content, surface temperature of rough rice, head rice yield, drying rate, power consumption per unit mass of evaporated water, and physical characteristics of rice. Parametric effects of the following variables are examined: velocity of drying air from 20 to 30 m/s, feed rate of rough rice from 150 to 350 kg/h, initial moisture content from 22 to 26% (wet basis), and drying air temperature from 35 to 70 C. From the experimental results, it is found that this drying method can be used for fresh rough rice with an initial moisture content of over 24% (wet basis). The drying process is able to lead to very rapid drying without any grain quality problems such as cracks in the rice kernel. The moisture content can be reduced to approximately 18% (wet basis) or about 5-6% of the initial moisture content within 3-4 s. The optimal drying air temperature is in the range of 50 to 60 C. A comparison of pneumatic conveying drying data obtained from the present study with fluidized bed drying data reported in the open literature is also discussed.

The drying rates curves in terms of moisture content versus elapsed drying time for white pepper seeds were obtained experimentally using a fluidized bed and a combined microwavdfluidized bed. The combined microwavdfluidized bed employs a microwave field to assist convective drying. For both procedures, the drying rates were found to be dependent on the inlet air temperature and velocity. Significantly improved drying rates were achieved utilized a combined microwavelfluidized bed drying compared with a conventional fluidied bed.

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The purpose of this study is to develop an infant incubator that is efficient, simple to implement, and can be utilized especially in the rural area of Thailand. Instead of the current one which employed electrical heater, an electrical operated heat pump infant incubator is designed. The requirement of the air conditioning system to provided the room temperature lower than the desired temperature in the incubator (30 -38 °C) in no longer needed. An electrical operated heat pump infant incubator using a simple four ways control valve will switch the incubator side to become evaporator when the ambient temperature is higher than the desired temperature and, in contrary, condenser in the when the ambient temperature is lower. A large mass heat exchanger attached to the indoor coils is desired to store energy sufficient that air temperature in the incubator would not drop lower than 0.5 °C from the set point between the compressor cut-out and cut-in. This application of heat pump could provided the opportunity for over six thousand small hospitals in the rural area of Thailand to employ the infant incubator.