 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Drying of High Moisture Paddy by Two-Dimensional Spouted Bed Technique) ผู้เขียน: Somboon Wetchacama, Somchart Soponronnarit, Thanit Swasdisevi, Somkiat Prachayawarakorn, Jinda Panich-ing-orn, Suchart Suthicharoenpanich สื่อสิ่งพิมพ์:pdf AbstractThe objectives of this research were to design and construct a two-dimensional spouted bed dryer with draft plates, to study drying kinetics of paddy, paddy quality and specific primary energy consumption. Experimental drying conditions were as follows: initial paddy moisture contents (Mi) of 31.1-45.6% dry basis (d.b.), inlet air temperatures (Ti) of 130, 140 and 150?C, hold-ups (H) of 20, 25 and 30 kg. Experimental results showed that minimum spouting velocity of drying air at the inlet of drying chamber was 15.4-16.4 m/s equivalent to velocity through the draft plates of 3.9-4.1 m/s. The operating parameters affecting drying rate and specific primary energy consumption were drying temperature and specific air flow rate or hold-up. Those affecting head rice yield and rice whiteness were initial and final moisture contents of paddy and drying air temperature. The entrance height directly affected energy consumption of the fan. The suitable entrance height was 10 cm as it resulted in minimum energy consumption. The first order polynomial equation was accurate and appropriate for predicting drying rate. |
หัวเรื่อง:การอบแห้งเมล็ดในมะม่วงหิมพานต์ด้วยเครื่องอบแห้งแบบถาดหมุน ผู้เขียน:Thanit Swasdisevi, Somchart Soponronnarit, Adisak Nathakaranakule, Pieamsin Thongthip สื่อสิ่งพิมพ์:pdf AbstractThe objective of this research is to investigate a suitable condition for drying cashew kernel with rotating tray dryer. Criterion used to consider are as follows: quality of product after drying, drying time and specific energy consumption. Experimental results showed that the drying time decreased when drying air temperature increased. The appropriate drying condition is at drying air temperature of 90?C, recycled air fraction of 0.45 and specific air flow rate of 70 kg dry air/h-kg dry cashew kernel (air velocity 0.07 m/s). The product quality after drying is acceptable while drying time is low. The specific energy consumption is 68.22 MJ/kg water evap. or 6.85 MJ/kg cashew kernel. Drying cost analysis is reported at 260 baht/kg water evap. or 26.13 bath/kg cashew kernel. |
หัวเรื่อง:การอบแห้งโดยใช้ปั๊มความร้อนในระดับอุตสาหกรรม ผู้เขียน:Thanid Madhiyanon, Somchart Soponronnarit, Thanit Swasdisevi สื่อสิ่งพิมพ์:pdf AbstractThe prototype of an industrial-scale heat pump dryer (HPD) was designed, constructed and evaluated for performance. Drying chamber contained four trolleys with product capacity of 600-700 kg. In the experiments, papaya glace' was dried in closed system at an average temperature of 55?C, specific air flow rates of 25-32 kg dry air / h - kg dry papaya glace' and the evaporator by-pass air of 81%. The papaya glace' with initial moisture content of 83-86% dry basis was dried to final moisture content of 12-14% dry basis within approximately 32 hours. No significant variation of the average final moisture gradient along horizontal and vertical of dryer was observed (due to uniform air distribution within drying chamber). The results of experiment indicated that drying rate decreased rapidly with time, while total power consumption remained nearly constant. At high initial moisture content, the rate of moisture removal was higher than that of low initial moisture content. (The maximum average drying rate and SMER were 9.34 kg water evap/h and 0.782 kg water evap/kWh, respectively. The maximum average MER is 9.21 kg water cond/h, and the relative lowest average specific energy consumption is 4.92 MJ/kg water evap. The (COPhp)sys varied from 4.2 to 4.9 which was higher than (COPhp)used obtained by the internal condenser load which varied from 3.3 to 3.8. This attributed to the excess heat rejected to atmosphere through the external condenser.) The quality of dried papaya glace' in terms of color was acceptable due to low drying temperature. In conclusion, HPD achieved high energy efficiency, and it was feasible to be commercialized, particularly in food drying industry. |
หัวเรื่อง:การพัฒนาแบบจำลองทางคณิตศาสตร์สำหรับการอบแห้งผลไม้โดยใช้ปั๊มความร้อน ผู้เขียน:Waraporn Rattanongpisat, Somchart Soponronnarit, Thanit Swasdisevi สื่อสิ่งพิมพ์:pdf AbstractA mathematical model for papaya glace' drying using heat pump has been developed. It comprises of drying rate equation, mass and energy balance equations, thermo-physical property of papaya glace' equations and heat exchanger equations. Successive substitution method was used for finding the solution. It was found that the model was fairly accurate for predicting final moisture content, air temperature at various parts in the system and temperature of refrigerant especially at low moisture level of papaya glace'. The mathematical model was then used to find out strategy for drying papaya glace' with a specific air flow rate of 29.8 kg/h-kg dry papaya glace'. Simulated results showed that drying time and energy consumption was decreased when the drying air temperature was increased. In addition, the appropriate bypass air ratio was in the range of 86-90 %. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Parameters for Mango Glace? Drying Simulation) ผู้เขียน:Somboon Wetchacama, Somchart Soponronnarit, Thanit Swasdisevi, Sakrin Ratsie สื่อสิ่งพิมพ์:pdf AbstractThe objective of this research was to investigate parameters affecting drying rate of mango glace?, i.e., diffusion coefficient, equilibrium moisture content, specific heat and density of mango glace?. The equilibrium moisture content was determined by static method at temperature of 45-70?C and relative humidity of 10-90%. Saturated salt solutions and an oven were used for controlling relative humidity and temperature, respectively. It was found that equilibrium moisture content decreased with temperature for relative humidity ranging from 10-60%. The BET equation was found accurate to describe the experimental results. The results obtained from drying experiment indicated that diffusion coefficient increased exponentially with drying temperature. It was further found that density and specific heat of mango glace? decreased and increased linearly with moisture content, respectively. |