Advanced Materials Research Vols. 113-116

Abstract: In order to build an emergency system for emergency accident of water pollution, the technological ideology of active emergency protection was put forward. The fixed point pollution source was taken as the study object and the diffusion model of water was used to set up the new method of water resource protection area division in active mode. Based on this new method, the water protection system with active control was built and the roles of different government departments in this system were given. The various active control technologies, such as storage tank for emergency accident, zero discharge, etc, discussed in this paper will help to water pollution control for emergency accident. The active mode method provides reference for water resources management.

Abstract: The Micro-Whirling Coagulation process whose core is the Micro-whirling reactor is the key to the Whirling Clarification technique. The Micro-whirling reactor and its working mechanism which is whirling-coagulation and contact-flocculation are illustrated in this paper. Also it tells us the application on clarification tank in one wastewater reuse plant of BAOSTEEL. After being alteration to the standard clarification tank which is put the Micro-whirling reactor into the first and second flocculation area and put the inclined pipes into the sedimentation area, the treatment scale of the whirling clarification tank is increased, the effluent turbidity of the tank is lower than 3 NTU, the effluent turbidity of finished water is lower than 1 NTU and the investment of per ton micro-whirling water is lower 35 yuan RMB. The paper argues that in comparison to other coagulation reactors, Micro-whirling reactor deserves widely application for its various advantages, such as its higher coagulation efficiency, shorter reactivity time, better quality of finished water, stronger adaptive capability, more conveniences in construction and the like.

Abstract: Crosslinked carboxymethyl modified starch (CCMS) was prepared by chemical modification of nature cornstarch. This modified degradable polymer had turned out to be a strong ability to chelate heavy metal ions. Using the instrument of microwave plasma torch atomic emission spectrometer(MPT-AES), 20.00 mg/L of Cu, Zn, Ni, Pb, Cd were detected under the Sewage Discharge Standards requirements after adding 90, 154, 86, 70, 546mg/L of CCMS respectively. The separation of the heavy metal ions and CCMS solutions were used the technique of ultrafiltration, with a molecular weight cut-off (MWCO) of 50000. By the same treatment, the chelating sequence of the heavy metals were also measured and decreased in the order of Pb>Cu>Cd>Zn>Ni.

Abstract: Much water body running in urban residential subdivisions in China is not successful, and deteriorated water and bad scenery happened frequently in rainy seasons. The main purpose of this study is to recommend a feasible water scenery planning program in urban residential subdivisions construction to improve water quality. Based on the detailed analyses, the main reasons of unsuccessful water running might lie in sustainable water resource shortage, improper water scale, water body structure, and subsequent weak self-purification ability. A feasible planning program was recommended, and a case design based on this program was presented. It is concluded that rainwater is a promising sustainable water resource to maintain water body. Such general planning as water scenery layout and scale, water balance analysis are main aspects in the water body construction design. If the results obtained in this study were extendedly applied, the water scenery in residential subdivision could be improved successfully.

Abstract: This paper has an explicit exposition on the study of waste PC-Main Board recycling by pyrolysis approach. The decomposing of PC-Main Board is completed above 400°C. For PC main boards around 77% solid residual (pyro-solid), 9 % pyro-oil and 14% pyro-gas were produced after the pyrolysis.The volatile detected by gas chromatography-mass spectrometry (PY-GC-MS) and the results indicated that:1) No significant influence of temperature on the products were observed over 400°C, only with the increase of temperature the small molecules volatile substance became a little high. 2) The characteristic pyrolysis products contained high concentrations of phenol, brom- phenol, while bisphenol A, tetrabromobisphenol A, methyl phenols, C1-C4 alkanes and alkanes were present.

Abstract: As a new strategy to effectively use wood and plastic wastes, composites of high content wood flour (WF) and recycled high density polyethylene (RHDPE), with and without maleic anhydride polyethylene (MAPE) as compatibilizer, were prepared by direct extrusion using a twin-screw/single- screw extruder system. The effects of MAPE on the properties of composite were investigated by mechanical tests, torque rheological analysis, scanning electron microscopy (SEM), and differential scanning calorimetry (DSC). The results demonstrated that MAPE greatly improved the mechanical properties of the prepared WF/RHDPE composites. This was attributed to the strong improvement effects of MAPE on the interfacial interaction of the composites, as was confirmed by the torque rheological and SEM analysis. According to the DSC results, composites with 60% WF content show lower crystallinity degree (Xc) and melting temperature (Tm) than RHDPE, but the values for Tm and Xc did not have noticeable changes with the addition of MAPE.

Abstract: A new hydrate-based gas separation (HBGS) method for recovering methane from low-concentration CMM was proposed. The objective of this study is to investigate the influence of the temperature increase, agitation, and pressure drop on the stability of memory effect. Results showed that (1) when the dissociation temperature is not higher than 25.00 °C, the decreases of subcooling and induction time in gas hydrate nucleation range from 0.16 to 1.06 °C, and 1.75 to 88.92min, respectively. But when the dissociation temperature is higher than 25.00 °C, the memory effect is destroyed notably; (2) the agitator type and agitation show little influence on the stability of memory effect; (3) the pressure drop renders notable influence on the stability of memory effect. The present study provides stability conditions of memory effect that will contribute to CMM utilization and to benefit for local and global environment.

Abstract: The experiment studies the phenomenon of simultaneous nitrification and denitrification (SND) in SBBR filled with polyurethane as micro-organisms immobilized carriers. Polyurethane fills in SBR as micro-organisms immobilized carriers, formation of a Sequencing Batch Biofilm Reactor (SBBR). Under the anaerobic/aerobic conditions, we studied the effects of C/P, C/N and DO on SND. The results showed that when COD was 400mg/L, C/P was 43.2~50.2, C/N was 9.41~11.9 of the influent, the concentration of DO was 3.31~4.01mg/L, the effect of TN removal was good. When C/P was 46.9, C/N was 10.3, the concentration of DO was 3.58mg/L, the removal rate of TN was 83.71%, TN effluent was 6.45mg/L. TN effluent followed byⅠA standard of “Discharge standard of pollutants for municipal wastewater treatment plant”. DO concentrations impact the forms of nitrogen in the effluent. C/P, C/N and DO play an important role on SND in SBBR filled with polyurethane. Controlling these factors effectively can inhance the effect of nitrogen removal.

Abstract: Rare-earth tungsten thermionic emission material was used in the high-temperature electrostatic dust removal technology. A static test facility was self-designed to explore the emission characteristic. XRD, SEM and EDS were used to analyze the microstructure and element distribution. Working in high-temperature and oxidizing condition, tungsten in the thermionic emission materials is oxidized to tungsten trioxide, but the rare-earth tungstate in the grain boundary has no chemical changes. In high-temperature and oxidizing ambience, there is oxidation and volatilization on the surface of rare-earth tungsten, resulting in materials loss. The degree of loss depends on the composition of gas.

Abstract: Bacterial strains with chlorimuron-ethyl degrading ability were isolated for bioremediation of contaminated soil. Six strains were obtained from chlorimuron-ethyl contaminated soil by enrichment cultivation. HPLC analysis indicated that two strains (A4 and A5) demonstrated high degradation efficiency than other strains. More than 61% of chlorimuron-ethyl was degraded by the two strains after 24 h. Based on the results of biochemical tests and 16S rDNA sequence analysis, the strain A4 and A5 were identified as Bacillus licheniformis and B. cereus, respectively. The cultivation conditions of the two strains were optimized to increase the biomass production.