Advanced Materials Research Vol. 1051

Abstract: Human beings have recognized that the philosopy of “Utilization of natural resources for economic reasons disregarding the need for replenishing these resources” would overexploitate all the natural resources in the world and realized that we must live by adapting to the nature in the modern 21^st century. This new development model is known as “Sustainable development”. The model is being implemented by many nations in the world regardless of whether they are big or small, developed or under developed. The “Sustainable development” model includes educational and development requirements that countries need to address in order to follow the model.This paper presents our hypothesis on the economic development model that fulfills the above requirements gipro-economics and documents the results of our research on this hypothesis.

Abstract: The pyrolysis characteristics of kitchen waste were studied and the optimal pyrolysis condition was obtained by analyzing the thermogravimetric curves (TG/DTG). Then a pyrolysis experiment was carried out using external heated rotary furnace with the throughput at 5kg/h and the heating rate ranging from 50°C/min to 200°C/min. In this experiment, the 3-phase products were collected separately and the distribution was tested. The composition and thermal value of the products were also analyzed.

Abstract: This study used four acid digestion methods and the Tessier five-step method to analyze the content characteristics of the elements Hg and As in samples. Further measures included the enrichment factor, geoaccumulation index and potential ecological risk index, for a comprehensive ecological risk assessment of pollution by Hg and As. The average contents were 1.16 mg·kg^-1 for Hg and 46.76 mg·kg^-1 for As.The two class natural background level was compared to evaluate the cumulative pollution index: among all sampling points, the Hg I_geo mean was-0.55, indicating this element was non-polluting, and the As I_geo mean of 0.23 indicated pollution-free to light pollution. The overall potential ecological risk index (RI) had a mean of 64.93, which indicated slight potential ecological harm to the wetland system.

Abstract: The article presents the results of the study to assess the impact of the tehnogenic system on the environment and technospheric protection during mineral resources development in the Amurskaya oblast (region). High ecological toxicity of tailings, contributing to the deterioration of the life environment. According to the authors’ research, here air pollution can be attributed to high level. At all pilot sites MPC level exceeding in soils and vegetation for arsenic, chromium, manganese, copper, zinc, lead, cobalt, antimony was determined. Analyzing total risk indexes for substances effecting the same systems and organs, the highest value was found for the group of substances affecting the human respiratory organs: suspended particles, sulphur dioxide. The measures reducing the impact of mineral processing wastes on the environment and the health of the mining settlements population in Khabarovsky Krai were developed.

Abstract: Guangxi rural contiguous environmental governance project was started in April 2011, with 88 sets of sewage treatment facilities, 22 sets of household garbage collection treatment facilities. The finishing of 74 sets of sewage treatment facilities, and 19 sets of life garbage collection treatment facilities revealed that this project start-up was basically normal. According to the situation of the contiguous rural environmental governance project in Lijiang River basin and the Red River Valley, it shows that the scale of rural sewage treatment facilities is generally small—the average scale is 107.2 m³/d, the average price of unit construction investment ( including pipeline construction ) is 6445 Yuan/m³, and the main treatment process is the bio-contact oxidation method + constructed wetland; the average price of unit construction investment on rural garbage disposal is 339.2 thousands of Yuan, garbage collection and clearance are the main processes, meanwhile the urban and rural garbage integration treatment mode — “household classification - village collection - township transfer - county treatment” is only carried out in the regions of nearby towns and convenient transportation.

Abstract: In this paper, 2000-2010 NDVI data of Liaohe Basin is obtained with the RS technology; the distribution map of precipitation and air temperature in Liaohe Basin is generated by the GIS technology, and then the temporal and spatial vegetation variation of Liaohe Basin and its relation with climate changes have been studied by means of raster data spatial analysis, correlation analysis and multiple regression analysis, so as to provide a scientific basis for ecological environment protection, planning and development of Liaohe Basin. It is shown from results that: 1) From 2000 to 2010, the vegetation coverage increased significantly; which presents a gradual decrease from east to west on the spatial distribution; 2) For the temporal distribution, the precipitation presents a fluctuant upward trend; while temperature is fluctuated significantly with a slight decrease. For the spatial distribution, precipitation decreased gradually from the east to west, while temperature rises from the northeast to southwest; and 3) Vegetation coverage of Liaohe Basin is positively related with precipitation and temperature in the temporal and spatial distribution, but not significantly, it is indicated that, except for the meteorological factors, the artificial impact and other factors, such as land use, played an important role to vegetation variation of Liaohe Basin in the recent 10 years. However in terms of two influence factors of precipitation and temperature, the former has significantly contributed to NDVI change of Liaohe Basin.

Abstract: Water quality on-line monitoring is the necessary means to control water environment pollution and provide effective data for the research of water ecological restoration. Using free wireless communicating module of ZigBee we realized transmitting data from sensors on the river bank to the data storage center. Based on serial ports of micro-controller a protocol converter circuit was designed. With program the Modbus RTU protocol data packet on RS-485 bus was converted into ZigBee communication protocol and then transmitted to the Internet. Supplemented by GSM the reliability of data was enhanced. Water quality online monitoring system based on multiple data communication provides browse of real-time river water quality through the Internet network, which is fast and convenient to be exported for research.

Abstract: Nitrogen is a naturally occurring element that is essential for growth and reproduction in both plants and animals. Excessive concentrations in the water body can cause excessive growth of algae and other plants, leading to accelerate eutrophication of lakes, and occasional depletion of dissolved oxygen. To remove nitrogen conventionally from domestic wastewater requires a high cost technology due to consumption of chemicals, high operational and maintenance cost. Therefore, an alternative low cost treatment technology particularly for nutrient removal including nitrogen removal system has been developed to improve the final effluent quality that is an aerated rock filter system. However, in the previous works in the UK the system was outperformed in removing ammonia nitrogen with limited nitrate removal. Hence, the present study was carried out to investigate the removal of nitrate from domestic wastewater through denitrification process using a lab-scale limestone filter. Domestic wastewater sample used in this study was collected from Taman Bukit Perdana Wastewater Treatment Plant (WWTP), Batu Pahat, Johor owned by IWK. The treatments were run in lab-scale limestone denitrification filter for 10 weeks. Effluent from nitrification filter was passing through the limestone denitrification filter as influent for further treatment. The in fluent and effluent of the filter system have been sampled and analyzed on biweekly basis for selected parameters including pH, alkalinity, temperature, dissolved oxygen, nitrate and ammonia nitrogen to monitor the effectiveness of the filter. Results from this study show that denitrification process has took place even the percentages of nitrate removal were considerably low but it seems promising with some modification of designing the the limestone filter to enhance denitrification process. The highest removal rate was 17.66%. Low removal of nitrate was inhibited within the filter system might be due to the high DO concentration as it was found that the range of DO was 4.75-7.78 mg/L. To permit the denitrification process to take place within the filter system, it is required an anoxic condition in the presence of nitrate with minimum DO concentration. Consequently, some modifications to the filter design will be considered in the future research in order to enhance the removal of nitrate through denitrification process.

Abstract: Adsorption of Cr⁶⁺ onto purified attapulgite was investigated with respect to temperature, initial concentration and contact time. The kinetics data related to the adsorption of chromium from aqueous solutions are in good agreement with the pseudo-second order equation in ranges of initial concentration of 20~200 mg/L, and temperature of 298~328K. The thermodynamic experiment results show that the equilibrium adsorption isotherm was closely fitted with the Langmuir model.

Abstract: Surfactant-enhanced permanganate oxidation (SEPO) technology utilizes the surfactant to mobilize and/or solubilize the dense-non-aqueous-phase liquids (DNAPLs) and then exploits the high oxidation capacity of permanganate (MnO₄^-) to oxidize them. SEPO technology has been shown as an effective way to remediate the aquifers contaminated with chlorinated organic pollutants such as trichloroethylene (TCE). Experiments were carried out with a series of continuous stir batch reactor to quantify the kinetic parameters of which MnO₄^- oxidizes the aqueous TCE in the presence of surfactant. It was found that TCE followed the observed pseudo-first-order reaction with respect to MnO₄^- whether the surfactants were present or not. In the absence of surfactants, the observed pseudo-first-order rate constant (k_obs) and half-life (t_1/2) were 0.12-0.25 min^-1 and 2.5-7.1 min for MnO₄^-, respectively. For the Tween80 concentration less than its critical micelle concentration (CMC), the k_obs value was 0.14 min^-1 and the t_1/2 was 2.6 min for MnO₄^-. As the Tween80 concentration exceeded its CMC, the k_obs values increased to 0.32-0.37 min^-1 and the t_1/2 reduced to 0.44-0.46 min. The results showed that combination of permanganate with a proper type of surfactant can speed up the removal of contaminants in aquifers.