Advanced Materials Research Vols. 807-809

Abstract: This study was conducted to investigate the efficiency and characteristics of de-nitrification using bamboo as solid phase carbon source in a batch and continuous flow mode. Compared to no solid phase carbon source system, the higher nitrate-N removal efficiency and the less nitrite-N accumulation was observed in a de-nitrification system by using bamboo as solid phase carbon source. The results showed that nitrate-N volumetric load averaged between 2.09 mg/L.h when filamentous bamboo as single carbon source, and mean nitrite-N accumulations was only 0.23 mg as 1 g nitrate-N was removed. Moreover, temperature was an important influencing factor for nitrate-N volumetric load and nitrite accumulation. In addition, refractory organic compounds and nitrate-N can simultaneous remove.

Abstract: In the paper, a new composite absorbent was prepared by diatomite and zeolite. The structure of the prepared composite absorbent was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron micrograph (SEM) and Energy dispersive spectrometer (EDS). In addition, the kinetics and thermodynamics properties of the new composite absorbent to the phosphate in aqueous solution were investigated as well. The results showed that, new crystalline phases and fresh bonds might be formed in the prepared composite absorbent. The metallic contents in materials interacted with diatomite, leading to the formation of inorganic polymerized silicon complex and the increasing of the element content of calcium, magnesium, aluminum and ferrum in the new composite absorbent. It was found that the pseudo-second-order equation could fit the adsorption kinetics well, and the adsorption isotherms could be qualified by the Langmuir equation.

Abstract: The research used activated carbon fiber (ACF) as adsorbent to remove atrazine, a kind of herbicide. It set a series of static adsorption experiments under different solution temperature, pH value and initial concentration to get a optimum adsorption condition. The experiment shows that the optimum pH for the removal of atrazine is 7. The adsorption rate is highest at 20°C. The adsorption rate decreases while the initial concentration increases.

Abstract: The influencing factors of reaction such as reaction temperature, reaction time and the ratio of liquid to solid are investigated by analyzing the iodine distribution in the semi-hydrate wet process of phosphoric acid. The result shows that with the increase of reaction temperature, reaction time and the ratio of liquid to solid, the iodine distribution in the phases of liquid and solid presents has the tendency of decrease, in the range between 20% and 30%, while the iodine distribution in the gas phase tends to increase, the maximum value is 67.54%.

Abstract: This paper studies the degradation of herbicide atrazine. It was degraded by three-dimension-electrode electrochemical oxidation, which platinum was used as cathode and anode, and activated carbon was used as packed material and adsorbent. The effect of input current, initial pH, electrolyte concentration and solution temperature on degradation efficiency of atrazine was discussed. The results showed that atrazine can be effectively degraded by three-dimension-electrode electrochemical oxidation. The optimal conditions of operation are as follows: input current is 30mA, initial pH is 4, solution temperature is 20°C, and electrolyte concentrations is 0.10mol/L. Under the optimal conditions, degradation efficiency of atrazine can reach more than 99%, and the degradation rate is highest.

Abstract: The removal of high concentration ammonia in wastewater was investigated by an indirect electrochemical oxidation method using titanium electrodes coated with ruthenium and iridium (RuO2-IrO2-TiO2/Ti). The effect of different initial pH on ammonia removal by electrochemical oxidation was studied. The concentrations variation of ammonia, total nitrogen, nitrate nitrite, and free cholorines, chloramines was analyzed under the conditions with and without pH controlling. The results indicate that ammonia removal efficiency was higher under the moderate alkaline condition than that under neutral one. During the electrolysis process, nitrate and nitrite concentrations were very low, even below their detecting limits. The concentrations of free chlorines and chloramines were significantly affected by pH, as trichloramine and free chlorines were mainly produced in the reaction without pH controlling, while monochloramine was mainly produced in a stable alkalescene.

Abstract: This study mostly investigated the influences of electrolytic conditions and the structure of electrospinning nanofibers electrodes on the degradation of methylene blue in details. For PAN and Fe/PAN electrodes, was prepared by electrospinning.It was found that the ESF electrodes with higher specific surface area, and higher mesopore percentage could be push the electrochemical degradation. As the same time, adjusted the initial pH, increased the current, and added to electrolyte also could improve the treatment effect of electrochemical degradation. After 90min of electrolysis, the color removal efficiency of methylene blue reached 97.6% at current with 100mA, supporting electrolyte of NaCl with 0.1mol/L and initial pH with 3~5. Under the same current conditions with the Pt-Fe/PAN anodes the color removal rate of degradation were higher efficiency than the other two anodes.

Abstract: Geo-environmental treatment projects had not been implemented in many old mines of China. Those mines environment has got increasingly deteriorated. So the government provides specialized policies and funding to solve the environmental problems of those mines. Based on the characteristics of the geological environmental treatment projects of old mines, the paper puts forward the principle and index of the treatment projects design and applies in the design of Fengshan limestone mine, Guangxi. It indicated that: (1)The geological environment problems are complex and diverse, and the treatment projects involve a multi-disciplinary cross which are environmental geology, ecology geology, geotechnical engineering, environmental engineering and landscape works. It needs to consider the follow key indicators: Geo-environment problems, Feasibility, Benefit, and social demand. (2) the limestone mine in FengShan is high 134m, and there had happened a collapse which had 2.1×10⁴ m³, and killed 6 people. The geo-environment problems include rockfall, rock collapse, land and vegetation destruction, and landscape damage. The mine local in the Leye-Fengshan International Geological Park in Guangxi, the requests for travel security and sight-viewing environment are extremely high. Therefore, drainage, anchoring, rockfalls platforms and rock carvings would be implemented for the purpose of transforming the mine into a sight spot in the park.(3) The treatment projects eliminate the geo-hazard and build the world-class carving attractions reflect the benefit of the project management from the environment, economy and society aspects.

Abstract: The development of a kind of subsurface sewage disposal device is to develop a subsurface sewage disposal device which uses physical filtration to improve water quality of some specific area. This device mainly consists of a pressure dissolved air vessel, purification filtrating equipment and a system controller. This device also uses modern control technology to make the water quality meet the requirement of the standard of domestic water and satisfy peoples demand for water by controlling the pressure and flow of water strictly and separate impurities and harmful substances from the sewage.

Abstract: On the basis of the design and calculation, motion analysis and structural analysis were carried out on hydraulic manipulator hand structure working in the radiation environment by using modeling and simulation technology. Concluded that the simulation results can be intuitive to inspect the kinematic characteristics of the manipulator hand structure, and provide the basis for the design of the control system.