Modeling for nitritation proce ss wa s discussed and analyzed quantitatively for the factors that influence nitrite accumulation. The re sults indicated that pH, inorganic carbon source and Hydraulic Retention Time (HRT) a s well a s bioma ss concentration are the main factors that influenced the conversion ratio of ammonium to nitrite. A constant high pH can lead to a high nitritation rate and re sults in high conversion ratio on condition that free ammonia inhibition do not happen. In a CSTR system, without pH control, this conversion ratio can be monitored by pH variation in the reactor. The pH goe s down far from the inlet level means a strongly nitrite accumulation. High concentration of alkalinity can promoted the conversion ratio by means of accelerating the nitritation rate through providing sufficient inorganic carbon source (carbon dioxide). When inorganic carbon source wa s depleted, the nitritation proce ss stopped. HRT adjustment could be an efficient way to make the nitritation system run more flexible, which to some extent can meet the requirements of the fluctuant of inlet parameters such a s ammonium concentration, pH, and temperature and so on. Bioma ss concentration is the key point, e specially for a CSTR system in steady state, which wa s normally circumscribed by the characteristics of bacteria and may also affected by aeration mode and can be increa sed by prolonging the HRT on the condition of no nitrate accumulation when no recirculation available. The higher the bioma ss concentration is, the better the nitrite accumulation can be obtained.

以颗粒污泥为研究对象，在序批式反应器中研究了不同运行模式（有厌氧段和无厌氧段两种模式）和不同碳氮比（COD 与NH4+-N质量比取6、10、14）下，颗粒污泥对氨氮、总无机氮的去除情况。比较了2 种运行模式应用于颗粒污泥脱氮中的差别和优劣。采用分段函数的方法对不同碳氮比下的氨氮去除曲线进行了分割，对曝气第一阶段（碳源富足阶段）和曝气第二阶段（碳源贫乏阶段）的氨氮去除曲线进行了拟合，发现其线性化特征明显。计算了不同碳氮比下曝气前后期氨氮去除速率，并简要分析了好氧颗粒污泥同步硝化反硝化脱氮的作用机理。

采用人工配制的模拟生活污水，研究序批式反应器（SBR） 中好氧颗粒污泥的培养。 实验结果表明:通过对进水碳源进行调控，反应器中形成了高活性具有同步硝化反硝化能力的好氧颗粒污泥，反应器中COD和NH3N的去除率分别为74.0%～92.8% 和82.3%～98.5%。颗粒污泥的粒径一般为0 5～1.0mm，MLSS 达到4.5g•L-1以上，SVI值约为32.5， 其有效生物量及脱氮性能远远高于一般的好氧活性污泥。

Urban waste solids are now becoming one of the most crucial environmental problems. There are several different kinds of technologies normally used for waste solids disposal, among which landfill is more favorable in China than others, especially for urban waste solids. Most of the design works up to now are based on a roughly estimation of the amount of urban waste solids without any theoretical support, which lead to a series problems. To meet the basic information requirements for the design work, the amount of the urban waste solids was predicted in this research by applying the gray theoretical model GM (1,1) through non2linear differential equation simulation. The model parameters were estimated with the least square method (LSM) by running a certain MATALAB program, and the hypothesis test results show that the residual between the prediction value and the actual value approximately comply with the normal distribution N (0,01212), and the probability of the residual within the range (-0117, 0119) is more than 95%, which indicate obviously that the model can be well used for the prediction of the amount of waste solids and those had been already testified by the latest two years data about the urban waste solids from Loudi City of China. With this model, the predicted amount of the waste solids produced in Loudi City in the next 30 years is 8049000 ton in total .

sole carbon source under nitrate respiration mode first for 6 week, and then can be turned to methane fermentation conditions. After 6 weeks processing, the specific rate of TA degradation under nitrate respiration mode reached 23.8mgTA (L•gVSS), more than two times of that under methane fermentation mode 11.4mg TA (L•gVSS). The TA reductive cleavers’population density increased about 6 times and 20 times after 30 days and 90 days acclimation. After a total of 90 days for the enrichment and acclimation, the fermentative bacteria which originally existed in the seed sludge nearly disappeared, and instead of them, the TA reductive and cleaving bacteria group was formed in the new consortia, which was confirmed by the MPN counts and roll tube counts. Compared with the control experiment, the acclimation period can be shortened by about 50%.