The Effect of Organic Loading Rate Variation on Digestion of Tofu Wastewater using PVC Rings as Growth Media in a Hybrid UASB Reactor

Abstract

Tofu wastewater contains high organic matter potentially pollute the surrounding environment. An appropriate process for treating tofu wastewater is an anaerobic process which utilizes microorganisms in degrading organic matter in condition where dissolved oxygen contained in very small amount. Tofu wastewater treatment in this study using Hybrid UASB reactor which its process is a process of incorporating suspended growth and attached growth process in one reactor. The Hybrid UASB reactor is an attractive alternative technology for treating various types of wastewater. The Organic Loading Rate (OLR) is necessary parameter as an organic period per day per reactor cross section. This process was influenced by loading factor based on the value of HRT 6-24 h with range of organic load variation between 4.8-20.99 kgCOD m-3 d-1. The objective of OLR variation is to evaluate the reactor performance during process optimization. The highest COD removal efficiency was 85.57% on the 171th day for OLR 5.2 kgCOD m-3 d-1 and HRT 24 hours. The effluent quality deteriorated significantly when COD load increased and HRT decreased. This process shows the degradation of organic load requires HRT 24 h to reduce organic. This process shows that organic load degradation requires long HRT for streamlined treatment. Consequently, the optimal OLR for treating the tofu wastewater was up to 5.2 kg COD m-3 d-1 and HRT 24 hours.