The effect of time and velocity variation in sequencing batches reactor on cod and bod, removal efficiency in tofu waste

The tofu industry produces liquid waste that can cause pollution if it is not processed first. Tofu liquid waste has the characteristics of containing high organic matter such as BOD and COD so that if it has directly discharged into the environment, it will reduce the carrying capacity of the environment. The purpose of this study was to determine and analyse the effect of variations in times and velocity of sequence batch reactor on the optimization of COD and BOD removal in tofu industrial wastewater by anaerobic bacteria originating from natural sediments. The method used is an experimental method where the method is to find the effect on other things controlled by using artificial waste. The removal of COD and BOD in tofu industrial wastewater can be done by biological treatment process with attached growth using Sequencing Batch Reactor. The reactor inoculated by the septic tank sediment was fed with artificial waste containing a concentration of COD of 7,000 mg/l and BOD of 2,000 mg/l. For 35 days, this reactor will be operated in batches. Results showed a decrease in BOD and COD parameters using a sequencing batch reactor with BOD concentration 176 mg/l and COD concentration 570 mg/l.

Combined compact anaerobic reactors and lamella settlers for decentralized sewage treatment

This work presents a compact plant's development and performance evaluation for the decentralized treatment of domestic sewage. The plant was conceived and installed in a house with four residents in Vicente Pires, Federal District, Brazil. Its purpose was to remove organic matter and solids using a low-cost biological treatment process that was simple to operate. The plant was essentially anaerobic, composed of an up-flow anaerobic reactor and an anaerobic filter, both associated with lamella settlers. It was operated under real conditions and monitored for nineteen months, with removal efficiencies (calculated over the medians) of 81% for COD, 83% for BOD, 51% for Total Solids, 55% for Total Volatile Solids, 87% for Total Suspended Solids, and 100% for Settleable Solids. The plant performed adequately, with no clogging between the plates of the lamella settlers or no offensive odours, and limited amounts of sludge and scum.

Assessing the performance of a UV/H2O2 process for removing TOC from petroleum refinery wastewater and the respirometric effects of adding UV/H2O2 treated wastewater to activated sludge from the refinery WWTP biological treatment process

The treatment of petroleum refinery wastewater was studied using a bench scale ultraviolet/hydrogen peroxide (UV/H2O2) process. The highest treatment performance of the bench scale UV/H2O2 process to reduce the total organic carbon (TOC) from the petroleum refinery wastewater took place at a reaction time of 45 min and a pH of 5.0. A three factor analysis of va riance (ANOVA) analysis verified that the initial H2O2/TOC molar ratio did not have a significant effect on the bench scale UV/H2O2 process treatment performance. The effects of adding UV/H2O2 treated petroleum refinery wastewater to activated sludge microorganisms form the refinery WWTP biological treatment process was studied using respirometry. Overall, the UV/H2O2 treated refinery wastewater inhibited the refinery activated sludge microorganisms. This occurred when the raw refinery wastewater was treated with a UV/H2O2 process for 45 min. with an initial H2O2/TOC molar ratio of 1.7 mol H2O2/mol C, an initial H2O2 concentration of 202 mg H2O2/L and a pH of either 5 or 7.

Assessing the performance of a UV/H2O2 process for removing TOC from petroleum refinery wastewater and the respirometric effects of adding UV/H2O2 treated wastewater to activated sludge from the refinery WWTP biological treatment process

The treatment of petroleum refinery wastewater was studied using a bench scale ultraviolet/hydrogen peroxide (UV/H2O2) process. The highest treatment performance of the bench scale UV/H2O2 process to reduce the total organic carbon (TOC) from the petroleum refinery wastewater took place at a reaction time of 45 min and a pH of 5.0. A three factor analysis of va riance (ANOVA) analysis verified that the initial H2O2/TOC molar ratio did not have a significant effect on the bench scale UV/H2O2 process treatment performance. The effects of adding UV/H2O2 treated petroleum refinery wastewater to activated sludge microorganisms form the refinery WWTP biological treatment process was studied using respirometry. Overall, the UV/H2O2 treated refinery wastewater inhibited the refinery activated sludge microorganisms. This occurred when the raw refinery wastewater was treated with a UV/H2O2 process for 45 min. with an initial H2O2/TOC molar ratio of 1.7 mol H2O2/mol C, an initial H2O2 concentration of 202 mg H2O2/L and a pH of either 5 or 7.

Refinery wastewater treatment via a multistage enhanced biochemical process

Petroleum refinery wastewater (PRWW) that contains recalcitrant components as the major portion of constituents is difficult to treat by conventional biological processes. An effective and economical biological treatment process was established to treat industrial PRWW with an influent COD of over 2500 mg L−1 in this research. This process is mainly composed of internal circulation biological aerated filter (ICBAF), hydrolysis acidfication (HA), two anaerobic–aerobic (A/O) units, a membrane biological reactor (MBR), and ozone-activated carbon (O3-AC) units. The results showed that, overall, this system removed over 94% of the COD, BOD5, ammonia nitrogen (NH4+-N) and phosphorus in the influent, with the ICBAF unit accounting for 54.6% of COD removal and 83.6% of BOD5 removal, and the two A/O units accounting for 33.3% of COD removal and 9.4% of BOD5 removal. The degradation processes of eight organic pollutants and their removal via treatment were also analyzed. Furthermore, 26 bacteria were identified in this system, with Proteobacteria and Acidobacteria being the most dominant. Ultimately, the treatment process exhibited good performance in degrading complex organic pollutants in the PRWW.