Research on the implementation and analysis of high-turbidity raw water for particle pre-treatment with a barrier board

In this research, the raw water presenting turbidity was sampled to simulate the change of the water quality. A barrier board was used to extend the flowing route and the level change of the overflow; carry out the pre-treatment of high-turbidity raw water. Particle detention time and the average flowing speed analyzed as well for comparing the removal effect with that in the physical field. The particle detention time is as follows: At 4-141 min, the operating time can be shortened; when this is less than 90 min, the effluent still can maintain a 50-88% turbidity removal rate and the water quality of the effluent can even drop to 530 NTU. During the test, most of the average flowing speed was within the operating scope of the rectangular Sedimentation Basin for which the removal rate was 61%-93% and the effluent turbidity was below 1,000 NTU and even up to the optimal 380 NTU. A total of 3 items meet the operating requirements of the Inclinometer Sedimentation Basin, presenting a 54%-72% removal rate and 1,000-1,650 NTU of effluent turbidity; and one item exceeds the operating requirements of the Inclinometer Sedimentation Basin, presenting a lowered 1,900 NTU of effluent turbidity from 3,800 NTU and a 50% removal rate. Large-size particles exist in the high-turbidity raw water, which tends to settle under the gravity effect during after a long-route flowing journey. For example, the turbidity of the influent is 4,300-5,300 NTU which was reduced to 920-750 NTU after the pre-treatment experiment presenting a 79-86% or higher removal rate.