Internal Circulation Anaerobic Reactor Production Startup And Operating Characteristics Of Study

The Internal Circulation Reactor (IC reactor), which was developed by Paques BV based on UASB reactors, can be operated at high reactor volume loading rates and high liquid up-flow velocity with low investment cost and space occupation.The alcohol and amylum production wastewater treatment project in a certain amylum Co.Ltd was studied in this paper. The process technics,characteristics of this kind of mixed wastewater and the general situation of treatment of the alcohol and amylum production wastewater were simply discussed, and the theory and technology of anaerobic fermentation, the Internal Circulation Reactor were simple analysed through quantities of literature. The paper mainly studied the start-up performance of the full-scale IC reactors treating high strength the alcohol and amylum production wastewater.Basing on the connection of the organism degradation and cellular compose in the IC, an influent model on organic loads M_n= M₁×(1+k)^n-1 was established. The project of influent wastewater were also presented. The inoculated sludge came from anaerobic dehydration sludge of domestic wastewater treatment plant of Zhengzhou city. At the beginning of the start-up, the sludge concentration of IC were 10g/L.The paper mainly analyzed the reasons leading to the acidification of the IC reactor and studied the remedy methods. The factors which affected IC reactor's COD removal efficiency such as the temperature and its fluctuation, the organic loading rate, the change of pH, VFA, HRT etc, and the operational characteristic were researched. The paper also studied the process of sludge granulation in the IC reactor with the help of the microscope.The start-up of the IC reactor lasted about 3 months from the October of 2006 to February of 2007. It has experience three stages: (1) 1-5 weeks, we explored low strength influent wastewater and maintain the wastewater strength(about 5000mg/L), at the same time improved the organic loads gradually. (2) 6-10 weeks, we improved the strength influent(about 8000mg/L) .(3) we used the wastewater strength at about 11500 mg/L. We fed the wastewater at 9,13,17,21 o'clock everyday intermittently. If the effluent COD,VFA,SS concentration and temperature,pH value,the condition of methane production are right, we can improve the quantity of feed wastewater in accord with the project. At last of the experiment, the COD removal of IC reactor exceeded 95%. A large amount of granular sludge has been cultivated in the IC reactor. All those indicate the IC reactor has been started up successfully.The Application of not only solved the pollution of the alcohol and amylum production wastewater efficiently, and improved local environment but also brought economic benefits to the Kangdi amylum Co.Ltd. The Internal Circulation Reactor can be operated at high space loads rate and high liquid up-flow velocity with low investment cost and space occupation, it has a promising future in wastewater disposal field.