Experimental Study On The Treatment Of The Wastewater Of Syrup With Anaerobic-aerobic Moving Bed Biofilm Reactor

When the syrup processing industry brings the huge economic efficiency to our country, it brings serious environmental promblems as well. Currently, it's hard to find any related report and particular engineering project of the syrup wastewater in either domestic or overseas. This paper has focused on this present situation: first, we established a small experimental mold of moving bed biofilm reactor in the lab; then, we studied the new treatment process of syrup wastewater disposal as well as improvement of the process. Finally, we decided the most effective way and the best running parameters.This paper has studied and discussed the application feasibility of this process in syrup wastewater. And decided which one was the best design and condition as well as its proper controlling parameters. The main research results are as follows:1. The efficient starting-up strategy of MBBR (moving bed biofilm reactor) has been inspected. After 3 days, with intermittent sludge-removal method, it could be found there was biofilm outgown from the bio-carrier of the aerobic MBBR reactor. Two weeks later, biofilm grew up maturely and the density of the biofilm tended to be stable, maintains about 1.2g/L. After 2 weeks, the removal efficiency of COD of the anaerobic MBBR reactor could reach up to 60% too.2. It was found that during the process of the acclimation stage, the dominant microbiota population was changing regularly: running ciliated protozoa, tubifex, ciliated protozoa, rotifers and vorticella, then arcella.3. The operation parameters of this combined process have been optimized. The experimental results that showed the optimal operation condition were: in the anaerobic MBBR section, HRT was 12 hours, DO was limited below 0.5mg/L and PH was about 5.5~7.5;in the aerobic MBBR,HRT was 8 hours, DO was between 3~4 mg/L and PH was between 6.8~7.2. Under this condition, the qualities of the effluent within this process could come to the first level of GB8978-1996. At this time, the optimum volumetric loading of the anaerobic section was 6.99kgCOD/(m3·d), and of the aerobic section was 1.75 kgCOD/(m3·d). During the whole process, the COD, SS and BOD5 removal efficiencies could respectively reach up to 96.9%, 93.5% and 99.2%. The removal efficiencies of these parameters achieved a high level and the system was working stably The results showed the facts that the success of using anaerobic-aerobic MBBR reactor in the treatment of high-density syrup wastewater was attributed to the high sludge concentration, long biological chain, no excess sludge, high rate of pollution removal dfficiency, reliable running and simple operation. Technically, it was completely feasible as well.