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For making timely and correct decisions for emergent pollution emergency of the water environment, combined with fuzzy integrated evaluation method, the model for the evaluation of emergency is established. Qinghe river basin is estimated in 3-level fuzzy integrated evaluation from 6 aspects. The results show that the score of emergent pollution emergency of the water environment of Qinghe river assessment is 3.9273,which close to a good level. The capacity of emergency support and emergency response is superior, and the abilities of emergency prevention, emergency decision-making and emergency recovery are relatively general, which should be completed.Emergent pollution emergency of the water environment is affected by many factors, a multi-target integrated evaluation system should be established. At present, the emergent pollution emergency system of water environment in our country still needs to be improved, the construction of which started relatively late, and the evaluation of which is at the exploration stage. To find the existing problems and shortcomings in emergency system of emergent pollution in water environment, the emergency evaluation index system is established, which improve the water environmental pollution emergency system. However, most of the indicators building the index system are qualitative, which has certain fuzziness when being estimated. Meanwhile it exists certain fuzziness when expressing characterizing attributes of the degree of realization and level of most evaluation indicators, and it is difficult to use specific, accurate data for quantitative description, generally it is expressed by fuzzy degree concepts like ‘Excellent, good, medium, qualified, bad’ and so on. Therefore, the emergent pollution of water environment is estimated by fuzzy integrated evaluation method in this paper.

The distribution of arsenic speciation can be applied to elucidate the mechanism of removal arsenic during treatment the water containing arsenic with molysite. In this study, the effect of initial pH on the distribution of arsenic speciation in arsenic-ferric precipitation was determined by a five-step sequential extraction procedure. And then further explore the mechanism of arsenic removal with molysite. This experimental results showed that the main mechanisms governing the arsenic removal with ferric chloride were specific adsorption and coprecipitation. Besides, as pH increased from 5 to 9, the arsenic-ferric coprecipitation played a more and more important role in mechanism of arsenic removal with molysite. At the same time, the water soluble state As and the non-specific adsorption As were barely detectable, which suggested that physical absorption had almost no effect on arsenic removal.

Through the numerical simulation method, the Reynolds stress turbulence model (RSM) was used to simulate the flow field of circumfluent cyclone separator with three different outer chamber heights. Three circumfluent cyclones (CFC), with different outer chamber heights, are compared with each other. Pressure fields, velocity fields and pressure drop have been investigated. The results show that in a certain range, the outer chamber height of circumfluent cyclone separator has an optimum value, which can have higher separate efficiency and lower pressure drop. This provides a strong theoretical basis for the local optimization design of the cyclone.

The paper introduced the source and harmfulness of heavy metal pollution in water environment and summarized the applications of the chemical method, physiochemical method and biological method in heavy metal pollution of sudden emergency accident. Meanwhile, the heavy metal pollution emergency processing technology of rivers, lakes and other water bodies were elaborated and the emergency engineering technology of heavy metal pollution in rivers and lakes were analyzed. Finally, the application of bioremediation on heavy metal pollution caused by sudden emergency accident was prospected.

The treatment efficiency of Da Huofang Reservoir water in low temperature and low turbidity period by Coagulation/Ultrafiltration process was investigated in pilot study, and the water quality treated by the process was compared with that by the traditional treatment process. When coagulant dosage is 30 mg/L, the average removal rates of turbidity, CODMn and UV254 were 89.2%, 47.3% and 52.8% respectively in the coagulation/ultrafiltration process, and the treatment efficiency was obviously superior to the traditional process. In the study of operation parameters optimization for Coagulation/Ultrafiltration process, the optimum membrane flux was determined that was 50 L/m2h. The cleaning membrane water was treated by coagulation sedimentation process, and the quality of effluent was good which was mixed with raw water for reuse, and the experiment indicated that this method did not affect the stable operation of Coagulation/Ultrafiltration process, eventually the water recycling rate was improved from 89% to 96.5%.

This article describes the simulation method of water temperature and the model classification of water quality in lakes and reservoirs, and classic model of ecosystem dynamics of lakes and reservoirs - BA model from the water quality parameters of the relationship between two aspects of the basic equations are introduced. On this basis, establish the eutrophication of ecological models of lakes and reservoirs.

In dealing with auto manufacturing wastewater, aerobic process was viewed as the follow-up treatment of anaerobic process. Studying on the system of aerobic contact oxidation, all kinds of factors (HRT, influent CODCr concentration, dissolved oxygen (DO), pH value, alkalinity) effect on removal efficiency of the anaerobic effluent CODCr, NH4+–N, NO3–N and turbidity. The results showed that: when the filtration rate is less than 0.0625ml•h-1, in the aerobic contact oxidation system ,the organic pollutant′s removal efficiency is very stable; in system, when dissolved oxygen concentration is greater than 10.00ml•h-1, its removal efficiency keep a higher level; aerobic process could remove 81% of COD of the influent，and the effluent COD could meet the qualityⅡ of Discharge standard of wastewater pollutants for industry(GB8978—1996) .

A series of intramolecular charge transfer (ICT) molecules containing six-membered N-heterocyclic electron acceptors, as well as their phenyl analogue, have been synthesized. The pyrazine derivatives exhibit the largest quantum yield, stokes shift and the longest emission maxima wavelength due to the appropriate electronegativity of pyrazine, while the triazine derivative has much lower quantum yield due to its too strong ICT. The methyl groups at N-heterocyclic rings also have influence on the optical properties by disturbing the molecular dipole moment.

The filter media from iron and manganese biological removal filter which w- as replaced by new termly can be re-used. The sand filter media was characterized u- sing the SEM and owns developed interspaces. Drying the sand filter media at 110°C, then inspect and analyse its character and mode of defluoridation。The results show as follows. Under the test condition ,the adsorption balance can come out in about 3 hou-rs , the fluoride sorption on the re-used matured filter media followed pseudo-second kinetics. The effect of defluoridation by the matured filter media will be better within the range of pH 3~7, and best at about pH 4.58. The primary mode of fluoride sorpti- on is chemism, but physical sorption is also in existence , and the adsorption isother- ms could be described by Langmuir equation. Contact-time is a vary important factor in the continuous-flow column experiment. The effect of fluoride removal is long，as the height of filter column is controlled as 40cm.The filter media from iron and manga- nese biological removal filter possess potential of perfect sorbent, space for deeply study and foreground of practical application.

Acclimation of short-cut nitrification aerobic granular sludge with aerobic granular sludge and nitrification sludge as seed sludge in a sequencing batch reactor(SBR) by controlling the pH, influent ammonia concentration, temperature and other conditions. Experimental results showed that the short-cut nitrification aerobic granular sludge with high ammonia and COD removal rate (95%) was formed successfully, and SBR can run long-term stably. DO at 6.0~8.0mg/L when the nitrosation rate remained stable at 50% ~ 60%, and lower DO levels within the reactor (2.0~3.0mg/L) nitrosation rates of up to 90%. Mature short-cut nitrification aerobic granular sludge average diameter of 2~3mm in between, MLSS of up to 10.162g/L, SVI minimum up to 22.63ml/g, moisture content is only 81.93%, total nitrogen removal rate of 40%, and carbon-nitrogen removal capability.