Treatment of wastewater from sugar industries using three-phase fluidized bed and fixed-bed column

• Main Author: De la Cruz, Katherine B.
• Format: text
• Language: English
• Published: Animo Repository 1998
• Subjects: Sewage > Purification > Biological treatment; Water > Analysis; Fluidization; Fluidized reactors; Distilling industries > By-products; Chemical Engineering
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/1850
• Institution: De La Salle University

Wastewater from sugar industries was subjected to a two-stage treatment scheme employing a biological three-phase fluidized bed and a polishing stage -- the fixed bed column. Two sets of experiments were carried out in this study -- with and without the addition of polymers. The experiments were varied according to different flowrates (low-2500, medium-3500, high-4300 ml/min) and two solid loadings (50 and 100 g). Samples were collected from the overflow of the fixed-bed column and analyzed for Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Total Solids (TS), Total Suspended Solids (TSS), Total Dissolved Solids (TDS), and color. BOD removal achieved after 12-hours treatment revealed that the addition of polymers increased percent BOD reduction from 47.50 percent to 66.67 percent. However, the percent COD reduction did not improve with the addition of polymer. A value of 48.84 percent and 40.00 percent were obtained for without and with polymers, respectively. Percent reductions in TS, TDS, TSS for without polymers are valued at 52.24 percent, 36.22 percent and 78.70 percent, respectively, while with polymers, 55.79 percent, 55.12 percent and 71.29 percent, respectively. The presence of microorganisms was confirmed using scanning electron microscope. pH values are maintained within range favorable for microbial growth (pH 6.5-8.5). Color reduction greatly improved with polymers. The highest reported percent change in absorbance or percent relative color reduction was 85.69 percent. In color units, the lowest value observed was 229 PCU.