Advanced Materials Research Vols. 610-613

Abstract: A systematic research has been presented to the situation of heavy metal pollution in the wastewater which flows through the mining area, tailings area, farmland and rive in a tungsten mine area of Ganzhou. The content of Cu, Pb, Zn, Cd in the wastewater sample had been determined through directly inhalation by flame atomic absorption spectrometry(FAAS). While the content of Cr, Ni in the wastewater was also determined after the collected wastewater sample had been adjusted to pH＜2 with nitric acid. The results show that Pb, Zn is the main pollution factors in the region. The pollution in the mining area is the most serious. It is a bit lower in the tailings area than in the mining area. The content of Zn in the farmland has exceeded the standard. And the water in the river that closed mining area is normal. The mining area and tailings area is not suitable for the cultivation of edible plants. Cement ditches should be set up for the wastewater which flows through the farmland

Abstract: An direct competitive immunofluorescence method was developed in plate to detect chlortetracycline residues in environment using the Lumichrome as fluorescent probe. Different reaction conditions such as pH , the concentration of antigen and antibody and incubation times were assayed. Under optimized conditions, chlortetracycline can be determined in the concentration range of 1×10-8--2×10-4 mol/L, and the linear equation was y=11.363x+93.026, R2=0.99. The detection limit of this method IC90 was 3.74×10-7mol/L. The recoveries of chlortetracycline at various spiking levels in the sludge samples ranged from 95.43% to 104.26%, with relative standard deviations of 3% to 6%. These data demonstrate that the excellent performance of the proposed method in the detection of chlortetracycline in water samples.

Abstract: In this paper, an innovative remote monitoring system for radioactive environments is presented. Many sites have radioactive contamination areas that range from tank farms to burial sites and process facilities that are being deactivated, where additional monitoring and characterization are required in order to protect workers health and safety. According to that, we proposed an innovative system which is cost-effective, readily deployable and can be used for monitoring, visual characterization and radiological/chemical sampling.

Abstract: The heavy metals including Pb, Cd, Cr, As and Mn emission characteristics of coal-fired power plant boilers, industrial boilers, lead and zinc smelters, cement kilns, and steel industries were studied in this paper. The removing effects of heavy metals by pollution control technology were analyzed. ICP-AES method was used to measure the contents of heavy metals in solid samples. In addition, M-29, the U.S. EPA isokinetic sampling method was used to sample heavy metals in the flue gas, and the sampled heavy metals were tested by ICP-AES-hydride generator system. For coal-fired boilers, heavy metal contents in descending order were Mn, Pb and Cd in the tested coal. The heavy metals’ emission concentrations of coal-fired industrial boilers were much higher than the heavy metals’ emission concentrations of power plants. For the lead and zinc smelters, Pb and its compounds in flue gas after cleaning can meet the emission standards. The heavy metal contents in the cement raw materials in descending order were Pb, Cr and Cd. For the sintering mixture, the heavy metal contents in descending order were Pb, Cr and Cd as well. The removal effects of heavy metals by existing pollutant control technologies in the various typical industries were also tested and analyzed in the paper. The research did in the paper made a scientific basis for controlling heavy metal emissions from typical industries.

Abstract: In order to study the distribution of gas concentration in air return corner, co-kriging is adopted to do the interpretation of gas concentration in air return corner and air volume is regarded as a covariate. The study is based on the gas concentration distribution in air return corner of 5916 working face in Longfeng coalmine and the results show that co-kriging interpretation results produce smooth curves of gas concentration distribution in air return corner. Gas in goaf of 5916 working face is mostly emitted from air return corner and the airflow velocity of air return corner is low and the airflow is in eddy state. The main dissolute could not dilute and excrete the accumulative gas. Therefore, gas in air return corner is an important dangerous source.

Abstract: Contents and distributions of heavy metals in surface sediments from the northern Beibu Gulf were analyzed using atomic absorption spectrophotometer. The results showed that the contents of Cu, Pb, Zn, Cr and Cd were 14.22～26.68, 31.85～54.59, 60.19～90.93, 29.95～67.95 and 0.030～0.130 µg•g–1, respectively, and average were 18.21, 38.88, 78.00, 48.46 and 0.09µg•g–1. The reducing environments in northern Beibu Gulf were attributed to organic matters and sulfide. The distributions of heavy metals showed the trend of higher along the coastal area and lower in the offshore area, generally controlled by terrestrial inputs, as well as hydrological conditions, depositional environments and so on.

Abstract: High quality air environment is needed for human health. Indoor air pollution comes from surface decoration materials and outdoor smoke pollution. In this paper, based on Differential Optical Absorption Spectrometry (DOAS), absorption spectra of main pollution gases HCHO, SO₂, NO, NO₂ are measured and their differential absorption cross sections are calculated. For ppm range of pollutant concentration, minimum measurement error of 9% is achieved by our experiments. It is sensitive for air pollution detection.

Abstract: A gas-particle separation system was established to study the filtration performance where twelve ceramic filters were divided into four groups. Filters in the same group will be cleaned by pulse back-flow at once. The pressure distribution and variation during filtration and pulse back-flow washing in four group filter and along filter length was measured. The main pressure drop occurs across the filter porous wall. The pressure at filter cavity decreases from the close end to open end of the candle filter. The gas velocity magnitude inside the filter system during filtration process is generally relatively low inside the vessel. The velocity increases as the gas passes across the filter walls and enters the outlet of the filter tube.

Abstract: The removal of dimethyl phthalate (DMP), which is a pollutant of concern in water environments, was carried out by sodium persulfate (SPS,Na₂S₂O₈) catalyzed by Ag⁺ combined with microwave irradiation. Effects of persulfate concentration, reaction time, microwave(MW) power and catalytic ion Ag+ on the degradation efficiency of DMP by persulfate were examined in batch experiments. The results showed that optimum Na2S2O8 concentration was 0.083mmol/L, and Ag+ concentration was 0.042 mmol/L. Increasing the MW irradiation time , persulfate concentration or Ag+ concentration might significantly accelerate DMP degradation. Catalytic ion Ag⁺ combined with microwave irradiation was an rapid method to activate persulfate, and thus to produce SO₄⁻ • which was a powerful oxidant and could degrade DMP effectively. About 80% of DMP and 70% of COD could be degraded in 140s under the conditions of 800W MW power.

Abstract: The solubility and absorption rate of CO₂ in monoethanolamine (MEA) promoted N-methyldiethanolamine (MDEA) aqueous solution were measured at normal pressure with temperatures ranging from 303.15-323.15K. The temperature and the mass fraction dependences of the solubility of CO₂ and CO₂ loading were determined. The influence of the mass fraction of MEA on the absorption rate of CO₂ was illustrated.