Industrial metabolism of chlorine: a case study of a chlor-alkali industrial chain

Substance flow analysis (SFA) is applied to a case study of chlorine metabolism in a chlor-alkali industrial chain. A chain-level SFA model is constructed, and eight indices are proposed to analyze and evaluate the metabolic status of elemental chlorine. The primary objectives of this study are to identify low-efficiency links in production processes and to find ways to improve the operational performance of the industrial chain. Five-year in-depth data collection and analysis revealed that system production efficiency and source efficiency continued increasing since 2008, i.e., when the chain was first formed, at average annual growth rates of 21.01 % and 1.01 %, respectively. In 2011, 64.15 % of the total chlorine input was transformed into final products. That is, as high as 98.50 % of the chlorine inputs were utilized when other by-products were counted. Chlorine loss occurred mostly in the form of chloride ions in wastewater, and the system loss rate was 0.54 %. The metabolic efficiency of chlorine in this case was high, and the chain system had minimal impact on the environment. However, from the perspectives of processing depth and economic output, the case study of a chlor-alkali industrial chain still requires expansion.     

Spatiotemporal coupling measurement of industrial wastewater discharge and industrial economy in China

With the industrial-level panel data on total output and wastewater discharge over the period of 1997 to 2018, this paper employs GIS and ESDA methods to empirically investigate the spatial relationship between industrial total output and wastewater discharge. In this paper, we empirically examine whether and how industrial wastewater discharge in a particular province may affect the wastewater discharge in its neighboring provinces. Results suggest that provinces (municipalities) with large-scale industrial sewage discharge are located along riversides and coastal areas and these discharges then gradually distribute to coastal, central, and western areas. Results also show a strong spatial autocorrelation of industrial wastewater discharge between the observed local province and its neighboring provinces which is increasing over time. In addition, there is also a significant spatial spillover effect of industrial wastewater discharge among neighboring provinces in China’s eastern and central regions, indicating a structural convergence of high-pollution industries.

     

工业园产业生态系统多样性评价研究

多样性是衡量开发区产业生态系统持续发展的重要内容,对开发区产业生态系统的组成完善、功能结构优化、规模竞争活力、稳定演化会产生重要影响。借鉴Shannon-Weaver生物多样性指数方法进行南通经济技术开发区产业生态系统结构多样性评价,类推多样性自然规律在产业生态系统的适用,结果表明,开发区产业结构组分多样性指数随整体产业规模扩大呈逐年下降趋势,系统存在不稳定;由结构元到结构网(Hu-Hc-Hn)产业生态系统中存在结构多样性递减趋势,系统功能多样性不完备。针对当前低碳经济产业发展要求,探讨了综合性开发区产业生态系统应采用改变新的组织形式、调整政策来恢复和保持产业系统调节功能的生态化模式,不仅为生态产业的构建和管理者提供决策依据,而且为调整组分、改善结构功能、提高竞争力提供较为直观的决策依据。     

Sulfur Dioxide and Material Damage

Whereas most estimates of material damage are based on industrial surveys, the estimates produced in this study were derived from material damage experiments and ambient air quality data. Air quality data on SO₂ were obtained from 200 or more monitoring sites primarily located in heavily populated or polluted areas. Material threshold damage function data were then compared with SO₂ levels, and an estimate of losses, as reflected in increased maintenance and replacement costs, was determined. Estimates of the total stock of various materials in use were derived from census and industry data and allocated geographically according to population. A substantial decrease in the ambient SO₂ levels, particularly in larger urban areas, has occurred during the past five years. From 1968 to 1972, the estimated amount of material damage from SO₂ in the U. S. decreased from $900 million/yr to less than $100 million. During this period, the estimated percentage of man made materials exposed to SO₂ levels exceeding the proposed secondary annual average standard (60 μg/m³) and primary annual average standard (80 μg/m³) in the U. S. fell respectively, from 20% to less than 5% and from more than 10% to less than 1%. Most of the present loss is attributed to corrosion damage of metallic surfaces that are normally exposed to the ambient environment.     

Mutagenicity and genotoxicity assessment of industrial wastewaters

The genotoxicity of industrial wastewaters from Jajmau (Kanpur), was carried out by Ames Salmonella/microsome test, DNA repair-defective mutants, and Allium cepa anaphase–telophase test. Test samples showed maximum response with TA98 strain with and without metabolic activation. Amberlite resins concentrated wastewater samples were found to be more mutagenic as compared to those of liquid–liquid extracts (hexane and dichloromethane extracts). The damage in the DNA repair defective mutants in the presence of Amberlite resins concentrated water samples were found to be higher to that of liquid–liquid-extracted water samples at the dose level of 20 μl/ml culture. Among all the mutants, polA exhibited maximum decline with test samples. Mitotic index (MI) of root tip meristematic cells of A. cepa treated with 5, 10, 25, 50, and 100 % (v/v) wastewaters were significantly lower than the control. Complementary to the lower levels of MI, the wastewaters showed higher chromosomal aberration levels in all cases investigated.     

滤料的应用及其发展

重点介绍原材料和纺织工艺对滤料发展的影响、国内外滤料发展的最新动向和最新的成果，指出了滤料发展存在的问题和今后发展的方向。     

standards for industrial duct construction

The Sheet Metal and Air Conditioning Contractors' National Association, Inc. has recently published standards for round industrial duct construction which are intended for use by designers of air pollution control and industrial ventilation systems. These standards provide a simple 3-step procedure for the selection of material gage, reinforcement systems, and connections based on clearly defined design parameters.     

Pyrolysis kinetics and residue characteristics of petrochemical industrial sludge

This study investigated the pyrolysis characteristics of sludge from wastewater treatment plants in the petrochemical industry and focused on the pyrolysis kinetics, elemental composition of residue, and volatile organic compounds (VOCs) of exhaust gas. As pyrolysis temperature increased to 773 K, the increasing rate of crude oil production tended to a stable condition. The result indicated that the optimal temperature of crude oil and water mixed production was 773 K. When pyrolysis temperature increased from 673 to 973 K, carbon, oxygen, nitrogen, and hydrogen concentrations of residue decreased and the sulfur concentration of residue increased. The concentrations of benzene, toluene,ethylbenzene, and styrene increased by the increasing pyrolysis temperature. We found that the reaction order of sludge pyrolysis was 2.5 and the activation energy of the reaction was 11.06 kJ/mol. We believe that our pyrolysis system is transitional between devolatilization and combustion.     

Emergy-based sustainability measurement and evaluation of industrial production systems

Environmental Science and Pollution Research - The sustainability of industrial production systems is considered to be the key to promoting green transformation and upgrading of manufacturing...     

Iron isotopic fractionation in industrial emissions and urban aerosols

A study on tropospheric aerosols involving Fe particles with an industrial origin is tackled here. Aerosols were collected at the largest exhausts of a major European steel metallurgy plant and around its near urban environment. A combination of bulk and individual particle analysis performed by SEM–EDX provides the chemical composition of Fe-bearing aerosols emitted within the factory process (hematite, magnetite and agglomerates of these oxides with sylvite (KCl), calcite (CaCO₃) and graphite carbon). Fe isotopic compositions of those emissions fall within the range (0.08‰ < δ⁵⁶Fe < +0.80‰) of enriched ores processed by the manufacturer (−0.16‰ < δ⁵⁶Fe < +1.19‰). No significant evolution of Fe fractionation during steelworks processes is observed. At the industrial source, Fe is mainly present as oxide particles, to some extent in 3–4 μm aggregates. In the close urban area, 5 km away from the steel plant, individual particle analysis of collected aerosols presents, in addition to the industrial particle type, aluminosilicates and related natural particles (gypsum, quartz, calcite and reacted sea salt). The Fe isotopic composition (δ⁵⁶Fe = 0.14 ± 0.11‰) measured in the close urban environment of the steel metallurgy plant appears coherent with an external mixing of industrial and continental Fe-containing tropospheric aerosols, as evidenced by individual particle chemical analysis. Our isotopic data provide a first estimation of an anthropogenic source term as part of the study of photochemically promoted dissolution processes and related Fe fractionations in tropospheric aerosols.     

Iron isotopic fractionation in industrial emissions and urban aerosols

A study on tropospheric aerosols involving Fe particles with an industrial origin is tackled here. Aerosols were collected at the largest exhausts of a major European steel metallurgy plant and around its near urban environment. A combination of bulk and individual particle analysis performed by SEM–EDX provides the chemical composition of Fe-bearing aerosols emitted within the factory process (hematite, magnetite and agglomerates of these oxides with sylvite (KCl), calcite (CaCO₃) and graphite carbon). Fe isotopic compositions of those emissions fall within the range (0.08‰ < δ⁵⁶Fe < +0.80‰) of enriched ores processed by the manufacturer (−0.16‰ < δ⁵⁶Fe < +1.19‰). No significant evolution of Fe fractionation during steelworks processes is observed. At the industrial source, Fe is mainly present as oxide particles, to some extent in 3–4 μm aggregates. In the close urban area, 5 km away from the steel plant, individual particle analysis of collected aerosols presents, in addition to the industrial particle type, aluminosilicates and related natural particles (gypsum, quartz, calcite and reacted sea salt). The Fe isotopic composition (δ⁵⁶Fe = 0.14 ± 0.11‰) measured in the close urban environment of the steel metallurgy plant appears coherent with an external mixing of industrial and continental Fe-containing tropospheric aerosols, as evidenced by individual particle chemical analysis. Our isotopic data provide a first estimation of an anthropogenic source term as part of the study of photochemically promoted dissolution processes and related Fe fractionations in tropospheric aerosols.     

Acoustic barriers obtained from industrial wastes

Acoustic pollution is an environmental problem that is becoming increasingly more important in our society. Likewise, the accumulation of generated waste and the need for waste management are also becoming more and more pressing. In this study we describe a new material--called PROUSO--obtained from industrial wastes. PROUSO has a variety of commercial and engineering, as well as building, applications. The main raw materials used for this environmentally friendly material come from slag from the aluminium recycling process, dust from the marble industry, foundry sands, and recycled expanded polystyrene from recycled packaging. Some natural materials, such as plastic clays, are also used. To obtain PROUSO we used a conventional ceramic process, forming new mineral phases and incorporating polluted elements into the structure. Its physical properties make PROUSO an excellent acoustic and thermal insulation material. It absorbs 95% of the sound in the frequency band of the 500 Hz. Its compressive strength makes it ideal for use in ceramic wall building.     

Quantifying NOx for industrial combustion processes

The objectives of this paper are to (1) identify the problems with many of the units that are used to report and regulate NOx, (2) show how to properly correct NOx measurements for oxygen-enhanced combustion, and (3) recommend a preferred type of NOx unit. The current variety of NOx units make comparisons difficult and can cause considerable confusion. NOx may be measured on a wet or dry basis, but it is commonly reported on a dry basis. The reported NOx may differ from the actual measurements, which may be converted to a specific O2 basis level. Nearly all of the measured NOx from industrial combustion systems is in the form of NO, which is converted to NO2 in the atmosphere. However, when given on a mass basis, the measured NO is commonly reported as NO2 for regulatory purposes, but may be reported as NO, NO2, or simply NOx in technical papers. Some existing regulations may penalize combustion technologies with higher efficiencies and lower flue gas volumes, such as oxygen-enhanced combustion. Confusion may occur when applying some of the "conventional" NOx units to oxygen-enhanced processes. A better unit is the mass of NOx generated per unit of production, which also incorporates the overall process efficiency into the emissions. That unit does not penalize more efficient processes that may generate more NOx on a volume basis, but less NOx on a production basis.