SHRIMP WASTEWATER TREATMENT PLAN

Abstract

In this research, scallop and sea cucumber bivalves of the species Holothoria lecospilota were used for the biological treatment of wastewater from shrimp farms in Gwatar Bay in the spring of 2017. Sedimentation, biological and aeration ponds were built on the side of the main pond for filtration, then bivalves were collected from the natural environment and placed in the bed of said ponds. The concentration of quality parameters was investigated in four stations, including station 1 (sea sample), station 2 (inlet water), station 3 (outlet sewage) and station 4 (water before entering the sea). The results showed that the concentration of parameters in the effluent of the main pool (Station 3) was significantly higher than other stations (P<0.05).

The results of the correlation test showed that the amount of filtration has a significant negative correlation with the quality parameters, so that the concentration of the parameters decreases with the increase of filtration. The concentrations of nitrate, phosphate, turbidity, EC, TDS and dissolved oxygen in the main pool are 0.67, 1.52, 22.36, 39.78, 20.21 and 9.49 mg/liter, respectively, and after filtration equal to 56 It was 0.0, 0.79, 16.81, 38.68, 16.45 and 12 mg/liter, which shows that the difference between the parameters before and after filtration is significant (P<0.05). Also, the amount of biological filtration in different time periods has a significant difference (P<0.05) so that the highest and lowest filtration rates were observed on the fifth day and the first day, respectively. 20, 48, 27, 22 and 2.5% of nitrate, phosphate, turbidity, dissolved solids and electrical conductivity were removed from the wastewater in the filtration process, respectively. Therefore, based on the results, it was determined that scallop bivalves have a high ability in the biological filtration of shrimp farming effluents and can be used as a suitable indicator for the filtration of breeding farms.