Effect of multiple pass system on cassava starch separation efficiency = การศึกษาผลของปริมาณน้ำวนกลับของไฮโดรไซโคลนต่อประสิทธิภาพการแยกแป้งมันสำปะหลัง


พิพัฒน์ ปัทมราชวิเชียร


วิทยานิพนธ์. (2007) 185 หน้า



Hydrocyclone is an alternative solid-liquid separator to replace centrifuge separator in cassava starch production process. An advantage of a hydrocyclone is that it has no moving part that may be abrased by solid particles resulting in a reduction of the separation efficiency. However, some misplaced particles flows out with water at the overflow of a hydrocyclone. This research thus aimed to reduce the starch loss in the separation process by using multiple pass system to recollect the starch loss in the separation process by using multiple pass system to recollect the misplaced particles in the overflowing fluid to increase the separation efficiency ; hence, decreasing the starch loss. A conventional hydrocyclone and multiple pass hydrocyclone with a diameter of 3.0 centimeter were designed base on Bradley's geometry, which is suitable for a starch-water separation application. Three operating parameters were varied in this study to compare the conventional and multiple pass systems. Experiments were performed at three levels of pressure drop (i.e., 2, 4, and 6 kg/cm²) ; two levels of starch slurry concentrations (i.e., 11 and 20 % w/w) ; five recycling ratios (i.e., 0, 0.25, 0.5, 0.75 and 1.00). Percent Recovery (%R), percent split (%Rv), cut size diameter (D50), and sharpness of separation (I) were determined to evaluate the separation efficiency. The experimental results showed that there was insignificant difference in the separation efficiency between the conventional hydrocyclone and the multiple pass system. In the case of process efficiency, multiple pass system can reduce % starch loss in concentration process. The highest separation efficiency of the multiple pass system was at high pressure drop, low feed concentration and high recycling ratio