there are two stages in project of qingdao yangcheng city sewage treatment plant. the first one is design dimension and the second is 50,000 m3 / d. given the total investment saving, occupation saving and convenience for operation management, as well as attention paid to both stages, design dimension in the first stage is 50,000 m3 / d, while the design dimension of sewage pre-processing is 100,000 m3 / d.
pre-treated sewage will enter into iceas biochemical reaction pool, the core architecture for sewage biochemical treatment. it is planned to build 4 groups of 8 iceas biochemical reaction pools. plat dimensions of one biochemical reaction pool: use tank as reaction pool, diameter is 38m, effective depth is 5.2m, free board is 1m, height of pool is 6.1m and effective volume is 5894m3.
1、add suspended filler into major reaction area;
2、add submersible mixer in original biochemical reaction pool;
3、add sludge recirculation system to make sludge flow back to front of reaction area.
original process of the biochemical pool in second stage is a2/o process. keep the respective volume (that is hydraulic detention time hrt) of anaerobic zone, hypoxia zone and aerobic zone and redivide these three functional zones to form six parts of hypoxia/aerobic - hypoxia/aerobic - hypoxia/aerobic. pour water of original water sections into hypoxia sections to save induced reflux, and add suspended biological membrane carrier filler into aerobic zone of the second and third sections at the same time. adjust sludge return ratio and influent flow distribution at site according to actual quantity and quality of influent. refer to above-mentioned table for a/o+mbbr operation mode adjustment of step-feed process.
after improvement, average removal rate of cod、nh4+-n、tn、tp is up to 85.27%、96.3%、65.4% and 86.7%, and average effluent is 35mg/l、1.33mg/l、13.37mg/l and 0.45mg/l, which are fitted with requirements of the national level a discharge standards.
add：huahui rd.6 e.p.industrial park gaocheng town yixing city jiangsu province prc.