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Anaerobic fermentative technology is an important route to solving environmental pollution and resources problems. Combined hydrogen and methane production in a two-stage process is a concept which has been developed in recent years Anaerobic biological treatment organic wastewater can produce large amounts of hydrogen and methane，which can be used as energy carrier. At present，the research focusing on the adjustment of fermentation hydrogen-methane production has been conducted. Furthermore, the simultaneous hydrogen-methane production was tested and optimized. However, it lacked combined hydrogen-methane production in an anaerobic reactor in literature so far. Based on preview experiment, the paper studied the simultaneous hydrogen-methane fermentation in an anaerobic baffled reactor (ABR) system. ABR has the advantage of biomass phase separation and integration of acidogenic and methanogenic processes to simultaneously conduct hydrogen-methane production during wastewater treatment. Through deep biohydrogen production, it can enhance the activity of hydrogen-producing acetogens (HPA) and the efficiencies of the combined hydrogen-methane fermentation system. It showed to enhance the activity of HPA was the key to the combined hydrogen-methane production.

This paper has proposed a new structure of lateral diagonal tensile piezoelectric driving feeder which based on the study of foreign advanced technology of piezoelectric feeding devices. It has analysed the driving source and material movement properties of the new structure, and carried out the experimental research and analysis that based on the theoretical analysis. According to these, we get the relationships between driving voltage and feeding speed, frequency and feeding speed and the relationships among voltage, frequency and driving current. Measuring the driving power and compared with the electromagnetic vibration feeder, we obtained that the piezoelectric driving feeder’s energy-saving effect is remarkable. The whole machine has the superior performance.

The natural attenuation process was studied by vadose zone simulating indoor to quantify the adsorption, biodegradation and volatilization of diesel oil. Through adsorption experiment, adsorption equilibrium time of diesel sewage by fine sand was 24 h, and maximum theoretical adsorbance to Total Petroleum Hydrocarbon (TPH) was calculated to 234 mg/kg. Through the contrasts of three columns, the first-order attenuation kinetics equations of biodegradation and volatilization in the diesel polluted sand layer of vadose zone and the half-life time were established. According to the experiments, absorption, biodegradation and volatilization all played important roles, they were very major roles in natural attenuation.

Study on migration and transformation rules of diesel fuels pollution by using two-dimensional plexiglass tank to simulate underground aquifers. Through regular monitoring of the sampling ports in total petroleum hydrocarbon content of the water to determine the diesel fuels in the medium sand aquifer in the migration process, and compute out parameters of diesel fuels pollution in the medium sand aquifer in the mathematical model of migration. This prediction of diesel fuels pollution in the migration of sand media. The results showed: the highest values of different sampling ports used by the time its location is closely related to distance to sources, the concentration rose to the highest value used in a short time. The sampling ports far away from the pollution spilling place rose to the highest value of concentration used in a long time. After diesel fuels leaked 40 d later, the simulation of pollutants reached the bottom slot, and diesel fuels can be calculated transfered with a speed of 1cm•d-1, and then after 20 d more, TPH can be moved to simulate the water tank side pollution of the aquifer region.

Comparative experiment of 3 medium sand columns was executed to research the influence of water content on natural attenuation of diesel fuels contaminated vadose zone. The results showed that: The lower the water content, the stronger capacity of retarding diesel fuels was. After a diesel fuels spill, the average concentration of TPH were 57.7 g•kg-1, 47.55 g•kg-1 and 31.95 g•kg-1 in medium sand with different water content (0.66 %, 8.00 % and 15.22 %). Besides, the TPH found 90 days after the natural attenuation degradated by 38 % and 44.62 % 4 of the initial contaminant load of the medium sand with water content 0.66 % and 8.00 %. Additionally, the higher the water content, the larger the microbial activity of sand was. Biodegradation was the important mechanism for natural attenuation of diesel fuels.

Fenton and Fenton-like reactions are regarded as high efficient methods in advanced treatment of nitrobenzene wastewater but both restrained in degradation of nitrobenzene in groundwater because of the low pH condition( less than 4 ) requirement and other problems such as secondary pollution by the irons in contaminated sites. This paper reports a new Fenton-like technology combined irons extraction from aquifer materials which were found in a nitrobenzene contaminated site in China with hydrogen peroxide catalytic oxidation. The simulate experiments were conducted to investigate the oxidation of nitrobenzene in groundwater by this method under the condition of neutral pH and 8~10°C. The comparison of different extraction agent and production rule of hydroxyl radical were both studied in this research. The results indicated that extraction had hysteresis property because the highest extracting efficiency occurred after 36h. Extraction agent DCB has the highest efficiency, for Fe3+ was 62.92% and Fe2+ was 30.17%. The highest removal efficiency could reach 80.2% while the mole ratio of nitrobenzene to H2O2 was 1:200. Three stages could found in hydroxyl radical generation process, in the first stage hydroxyl radical generated rapidly in 0~30min, then decreased slowly between 30min and 120min, at last the generation tended to be steady after 120h. The results could possess a good potential for application in the treatment of nitrobenzene contaminated groundwater and provide theoretical basis on in-situ chemical remediation technology of nitrobenzene contaminated sites.

Natural attenuation of BTEX and characteristics of the water in the study are researched in this paper. The study not only obtain the attenuation rules of BTEX over time, but also the rules of the redox materials of the contaminated groundwater over time. From the study, we reach conclusion that the redox conditions is changed with the increasing pollution of BTEX and the oxidation condition changes into reducing condition. With the changing of the redox condition, there take place a variety of redox reactions. The materials of oxidation, such as O2, NO3-, Fe3+and SO42-, are transformed into reduction materials, such as NO2-, Fe2+, S2- and so on. In this process, the components of BTEX are degradated by micro-organisms which using the oxidation materials as electron acceptors.

This paper deals with the influencing factors on removal of diesel oil from by soil vapor extraction (SVE) method. A series of one-dimensional column experiments were conducted to study the influencing factors for SVE method, the factors included extracted vapor flow rate,water content and the concentration of the contaminant. The results indicated that: (1) the increase of vapor flow rate led to higher contaminant removal efficiency,but the increment of removal was not significant at higher flow rate levels;(2) the moisture content is 12% coarse sand elimination rate is bigger than 1% coarse sand;(3) the soil index of oil is higher, the extraction time to be longer, it is not suitable processes with SVE that the diesel oil density is excessively low.

Based on the mechanism of vibrating stress relief and standard of JB/T5926-2005, vibrating stress relief method is used to eliminate residual stress of crane beam flange with butt weld. The welding residual stress of measured points is obtained by using blind-hole method. Experimental results show that the peak value of residual stress is reduced significantly, and the stress decline rate of residual stress is greater than the minimum requirement value of JB/T5926-2005. The effect of VSR method is remarkable.

During numerical simulation of welding process, the temperature field simulation is fundamental for simulating other issues of welding process, and establishing the heat source model is the most basic work for temperature filed simulation. Based on the analysis and induction of arc welding heat source model used in T-joint welding simulation, points out the existing problems and future development direction of heat source model for T-joint, provides a reference for further research and practical application.

A mathematical model for getting the closed-form solution of main parameters of cylinder exhaust port is present, based on a few known parameters of variable-stroke engine (VSE). Considering lack of parameters in the initial stage of design, empirical formula is applied to solve the initial specific time-area value of exhaust port, and the initial port timing angle is solved by using logarithmic alignment method, thereby height and width of the exhaust port can be solved, then the precise specific time-area value and port timing angle are solved by using the coefficient calculation method and logarithmic alignment method respectively, so that the relative errors between initial and precise values of specific time-area value and port timing angle are defined as the relative errors of the mathematical model. Application examples show that the relative errors of the model is less than 3%.