【正文】 ime in the second pond, easy cause lack of oxygen, produce sludge upfloating decay。 When the aeration time is too long, high nitrification occurred in the pool, the nitrate concentration is high, in the second pond, prone to denitrification, produce nitrogen gas, sludge floating。 In addition, the oil content in the waste water is too large, the sludge may carry oil to rise. After sludge floating water shall be suspended, break or removal of the sludge, ascertain the reason, adjust the operation. Sludge settle ability is poor, can dosing coagulant or inert material, improve the precipitation。 Such as water load should be reduced into water or step back flow。 Such as the sludge particles small can decrease the aerator speed。 Denitrification is found, should reduce air, increasing the backflow or mud。 Sludge decay is found, should increase air, and clean up mud, hydraulic conditions and try to improve in the pool. And uneven velocity of sludge deposition problem In Carrousel Moseley oxidation ditch, for its unique mixing and processing results, the mixture must be circulating in the groove at a certain velocity. It is generally believed that the minimum flow rate should be m/s, the average velocity of sedimentary does not occur should be ~ m/s. Oxidation ditch aeration equipment generally brush turn for aeration and aeration rotary brush turns the submerged depth of 250 ~ 300 mm, submerged depth of the wheel is 480 ~ 530 mm. With oxidation ditch depth ( ~ m), pared to brush only 1/10 ~ 1/12 of the water depth, turntable also accounts for only 1/6 ~ 1/7, so the oxidation ditch caused by upper flow velocity is larger (about ~ m, or even more), and at the bottom of the flow rate is small (especially in depth below twothirds or 3/4, mixture had little velocity), the cause of a large number of mud (sometimes mud thickness up to m), greatly reduces the effective volume of oxidation ditch, reduces the treatment effect, influence the effluent water quality. Upstream or downstream equipped with guide plate is to improve the velocity distribution, the effective method to improve aerobic capacity, and the most convenient measures. Guide plate installed upstream from the rotary axis of turn (brush) (upstream), the guide plate height of water depth of 1/5 ~ 1/6, and perpendicular to the surface installation。 Downstream of the guide plate is installed in is apart from the wheel turn (brush) axis of m. Guide plate material can be made of metal or glass reinforced plastics, but is better to glass fiber reinforced plastic. Guide plate pared with other measures for improvement, not only does not increase the power consumption and operating costs, but also can greatly improve the efficiency of oxygen transfer ability and the theory of motivation. In addition, through setting underwater in the aerator upstream driver can also turn on aeration brush at the bottom of the low speed region mixture flow circulation play a positive role, so as to solve oxidation ditch of velocity is low, the sludge sedimentation problem. Set the underwater vehicle is dedicated to promoting mixture operation mode of oxidation ditch can be more flexible。 to save energy and improve efficiency is of great significance. 5. The development of Carrousel oxidation ditch Due to biological nitrogen removal in sewage treatment standard requirements more and stricter, Carrousel Moseley oxidation ditch also got further development. At present, the research and application more consists of the following two types: type micro porous aeration Carrousel 2000 System, Carrousel 3000 System. Microporous aeration Carrousel 2000 System Microporous aeration Carrousel 2000 System using Microporous aeration (oxygen supply equipment for blower), the Microporous aeration device can produce a large number of tiny air bubble diameter of 1 mm or so, which greatly improved the bubble surface area, and makes the pool volume increase certain cases total oxygen transfer (such as pool depth increases the mass transfer efficiency will be higher). According to the current technical ability of blower manufacturer, pool the effective depth of up to 8 m, so can according to different technological requirements to select suitable water depth. Push of traditional oxidation ditch flow is to use brush, disc or inverted umbrella table exposure machine, its low equipment utilization rate, low power consumption. Microporous aeration Carrousel 2000 System is used underwater flow way, namely fixed the propeller driving force generated in the impeller directly ACTS on the water, while pushing flow effect and can effectively prevent the sedimentation of sludge. Thus, adopting the submarine propeller both reduces the power consumption, and mud got fully bined. Carrousel 3000 System Carrousel 3000 System is in front of the Carrousel 2000 System bined with a biological selection area. The biological selection area is the screening of strains with high organic load, suppress the growth of filamentous bacteria, and improve the removal rate of each pollutant, the subsequent process principle with Carrousel 2000 System. Carrousel 39。s considerable improvement in performance in 3000 Systems: one is to increase the pool is deep, can reach ~ 8 m, concentric circles type, wall sharing, reduce cover an area of an area, reduce cost and at the same time could improve the ability of resistance to low temperature (up to 7 ℃)。 Second, the clever design of the aeration equipment, table under exposure machine installation guide tube, suction oxygen mixture, using underwater propeller flow problem。 Three is the use of the advanced QUTE aeration controller (it USES a kind of multivariable control mode). Four is to use integration design, starting from the center。 continuous process unit consists of the following rings: into the Wells and to return water segregator of activated sludge。 consists of four parts selection pool and biop tank respectively. It is outsi