Abstract

The aim of this study is to know the impact of Total Suspended Solids (TSS) and seasonal variation on Chemical Oxygen Demand (COD) values and characterization of untreated composite sample of wastewater of potato French fries processing industry. The wastewater parameters covered in this study are pH, biochemical oxygen demand (BOD 3 at 270C), COD and TSS. The impact of seasonal variation on wastewater quality of potato were studied and found that COD and TSS in increasing order as potato becomes older as compared to the fresh crop. This study shows the relation between COD and TSS after coagulation flocculation process in lab scale. The process of coagulation and flocculation is conducted without changing the pH (increase or decrease) of the wastewater by using polymer 459 (Cationic coagulant – solution of inorganic basic salt of chloro aluminium) and Setfloc 81 (Flocculant /polyelectrolyte, Anionic Acrylamide polymer) as a flocculant. The TSS values reduced in range of 71% to 75% which were contributing to the range of 32% to 50% of total organic load in terms of COD. The COD, BOD 3 at 270C, and TSS increased up to 31.68%, 40.11%, 43.18% and 5.03% respectively with time as the potato becomes older due to storage as compared to the fresh potato used for the processing. The COD analysis pre and post starch recovery of wastewater of cutter process was studied separately. Specific to the wastewater of cutter process the COD value reduced in range of 72% to 78% after starch recovery. The TSS removal reduced the organic load as COD up to 50% after coagulation flocculation which will require minimum energy footprint for maintaining dissolved oxygen supposed to be supplied by power driven surface aerators and will reduce CO2e reduction with minimum wastewater treatment cost. The type and quality of the potato were not studied in this report.

Keywords: Wastewater, Potato processing, Physico-Chemical, Organic load, TSS, COD