[Nitrogen removal performance of ANAMMOX ABR process in tannery wastewater treatment].

Anaerobic ammonium-N removal from tannery wastewater was investigated using a lab-scale anaerobic baffled reactor (ABR). The results indicated that ABR could be used as a good anaerobic ammonium oxidation reactor, the stable and effective performance of ammonium-N and COD removal from tannery wastewater was demonstrated in the ANAMMOX ABR. When the NH4(+) -N concentration of the influents were in the range of 25.

[Analysis of microbial community variation in the domestication process of sludge in a sulfate-reducing reactor].

The variations of microbial community in the sludge of sulfate-reducing UASB during domestication period were analyzed by PCR-DGGE technique. The results showed that the diversity of microbial community was strongly related to the sulfate reduction and COD removal performance. The sulfate reduction rate of the reactor was about 95% when the Shannon index of microbial community was higher than 3.

Simultaneous ANAMMOX and denitrification (SAD) process in batch tests.

The occurrence of simultaneous anaerobic ammonia oxidation and nitrate reduction (SAD) processes by enrichment culture in the presence of glucose were clarified in batch tests. Nitrate conversion and the formation of interim by-products were investigated under autotrophic and mixotrophic conditions. Eventually, the nitrite was fully consumed and co-occurred with ammonia oxidation.

[Desorption kinetics of 1,2,4,5-tetrachlorobenzene in sediments].

Sediment desorption batch technique experiments were conducted to study the influence of different types of natural organic matter (NOM) of sediment, initial solid-phase solute loading levels and temperatures on the desorption rates of 1,2,4,5-tetrachlorobenzene. A 4-parameter biphasic first-order kinetic model described the desorption of 1,2,4,5-tetrachlorobenzene from the sediments. The results indicate that the rate constants k(s) for the slowly desorbing fraction of each sample is up to 2 orders of magnitude lower than the corresponding rate constants k(r), for the rapidly desorbing fraction, suggesting that the slow desorption is the rate-limiting step.

[Nonlinear sorption behaviors of chlorobenzenes on sediments].

Sorption isotherms of chlorobenzene, 1,4-dichlorobenzene, 1,2,4-trichlorobenzene and 1,2,4,5-tetrachlorobenzene on 5 sediments were examined to understand its sorption behavior. All systems examined exhibits nonlinear sorption. All sorption isotherms are nonlinear as evidenced by the Freundlich n values of 5 sediments being between 0.

[Kinetics and mechanism analysis of the degradation of hexachlorbenzene in water by advanced oxidation process].

The degradation characteristics and rule of hexachlorobenzen (HCB) in water were studied and the results were compared by the advanced oxidation process UV, O3 and UV/O3. The experimental results showed that UV itself did not contribute to the removal of HCB obviously and HCB could be quickly degraded by O3 and UV/O3, namely UV < O3 < UV/O3. But in the case of O3 and UV/O3, raising the initial pH value of the system could not raise the removal rate of HCB, and the removal efficiency of 0.

Chlorobenzenes in waterweeds from the Xijiang River (Guangdong section) of the Pearl River.

The Xijiang River is the major source of water for about 4.5 millions of urban population and 28.7 millions of rural population.

[Hydrodynamic effects of the oxidation ditch on the removal efficiency and energy consumption].

The hydrodynamic characteristics in the oxidation ditch have great effects on the distributions of the dissolved oxygen and the velocity gradient, and then make important effects on the removal efficiency and energy consumption. The single-ditch Passver oxidation ditch with the capacity of 500 m3/d was investigated. The measurement and computer simulation were carried out on the velocity gradient and degrees, 180 degrees, respectively, which lied on the corner of the downriver of the aerator.