Hydrogen inhibition effect of chitosan and sodium phosphate on ZK60 waste dust in a wet dust removal system:A feasible way to control hydrogen explosion

Wet dust removal systems used to control dust in the polishing or grinding process of Mg alloy products are frequently associated with potential hydrogen explosion caused by magnesium-water reaction.For purpose of avoiding hydrogen explosion risks,we try to use a combination of chitosan(CS)and sodium phosphate(SP)to inhibit the hydrogen evolution reaction between magnesium alloy waste dust and water.The hydrogen evolution curves and chemical kinetics modeling for ten different mixing ratios demonstrate that 0.4wt%CS+0.1wt%SP yields the best inhibition efficiency with hydrogen generation rate of almost zero.SEM and EDS analyses indicate that this composite inhibitor can create a uniform,smooth,tight protective film over the surface of the alloy dust particles.FTIR and XRD analysis of the chemical composition of the surface film show that this protective film contains CS and SP chemically adsorbed on the surface of ZK60 but no detectable Mg(OH)_(2),suggesting that magnesium-water reaction was totally blocked.Our new method offers a thorough solution to hydrogen explosion by inhibiting the hydrogen generation of magnesium alloy waste dust in a wet dust removal system.

Development of dust collection and removal technology of comprehensive mechanized excavation face

To solve the problem of excavation face dust control,the theory of dust removal after collection was put forward.Through a large number of theoretical and experimental researches,a new wind screen dust-collection system which was applied to comprehen- sive excavation face was developed.To set a wind dam in jet stream box,achieve the function of multi-stage and multiple-level regulation,lots of experimentation was carried out to obtain higher jet stream velocity with the minimum loss of energy.Experiments show that the slit width in the exports of wind screen dust-collection system should be 10 to 15 mm.For the general excavation roadway,after wind attenuation,the velocity can be greater than 3 m/s at the roof which meets the requirements of respirable dust control.

Aerosol Filtration Application Using Fibrous Media—An Industrial Perspective

Filtration of aerosol particles using non-woven fibrous media is a common practice for air cleaning. It has found wide applications in industries and our daily lives. This paper overviews some of these applications and provides an industrial perspective. It starts from discussing aerosol filtration theory, followed by a brief review on the advancement of filtration media. After that, filtration applications in respiratory protection, dust collection, and engine in-take air cleaning are elaborated. These are the areas that the author sees as the typical needed ones in China's fast pace economical development endeavor, where air filtration enables the protection of human health, environment and equipment for sustainability.

Enhancement of Cathode Dust Collection and its Application in Improving the Efficiency of Dry Electrostatic Precipitator

As the main equipment of flue gas dedusting in coal fired boiler,electrostatic precipitator(ESP)can meet the requirements of emission standard for air pollutants from coal-fired power plants through improving the efficiency of ESP and combining with desulfurization system while not installing wet ESP(WESP).This paper introduces the modifications of ESP cathode structure to improve the efficiency of dust collection by reducing the secondary dust loss at cathode.The application of cathode dust collection provides a reference for the improvement of ESP dust collection efficiency.

Advances in air pollution control for key industries in China during the 13th five-year plan

Industrial development is an essential foundation of the national economy,but the industry is also the largest source of air pollution,of which power plants,iron and steel,building materials,and other industries emit large amounts of pollutants.Therefore,the Chinese government has promulgated a series of stringent emission regulations,and it is against this backdrop that research into air pollution control technologies for key industrial sectors is in full swing.In particular,during the 13th Five-Year Plan,breakthroughs have been made in pollution control technology for key industrial sectors.A multi-pollutant treatment technology system of desulfurization,denitrification,and dust collection,which applies to key industries such as power plants,steel,and building materials,has been developed.High-performance materials for the treatment of different pollutants,such as denitrification catalysts and desulfurization absorbers,were developed.At the same time,multi-pollutant synergistic removal technologies for flue gas in various industries have also become a hot research topic,with important breakthroughs in the synergistic removal of NO_(x),SO_(x),and Hg.Due to the increasingly stringent emission standards and regulations in China,there is still a need to work on the development of multi-pollutant synergistic technologies and further research and development of synergistic abatement technologies for CO_(2) to meet the requirements of ultra-low emissions in industrial sectors.

Occurrence of aryl and alkyl-aryl phosphates in Canadian house dust

This study investigated the occurrence of 19 aryl phosphates and mixed alkyl-aryl phosphates in dust samples(n=144)collected under the Canadian House Dust Study(CHDS).The predominant target analytes,detected in 100%of the samples,were isodecyl diphenyl phosphate(IDDPP),cresyl diphenyl phosphate(CDPP),and isopropylated triaryl phosphates(ITPs),with median concentrations of 1225(248-17850)ng/g,91(14-57700)ng/g,and 805(203-152000)ng/g,respectively.ITPs included isopropylphenyl diphenyl phosphate(IPPDPP),bis(isopropylphenyl)phenyl phosphate(BIPPPP),and tris(isopropylphenyl)phosphate(TIPPP).Strong correlations were found among IPPDPP,BIPPPP,and TIPPP,suggesting that there might be various consumer and building products containing mixtures of these substances.Bisphenol A bis(diphenyl phosphate)(BPA-DP)and resorcinol bis(diphenyl phosphate)(RBDP)were detected in 69%and 78%of samples,with relatively low median concentrations of 30(max:818)ng/g and 14(max:307)ng/g,respectively.Since the usage of OPEs as flame retardants has increased over the past decade,the current levels of OPEs in Canadian house dust could be higher than those reported in this study,where the samples were collected in 2007-2010.Further monitoring of OPEs in various environmental and biological matrices is recommended.