化学法处理电镀废水的自动化控制应用

采用化学法自动控制处理含铬和含镍电镀废水,选择合适的化学药剂和pH、ORP控制参数,连续式处理电镀废水.运行结果表明:该工艺简单、处理效果良好、运行稳定、可操作性好、运行成本适中、能很好的适应水质的波动,处理后的水质完全符合排放标准.     

ORIGIN AND TRANSPORT OF DISSOLVED CHEMICALS IN A KARST WATERSHED,SOUTHWESTERN ILLINOIS1

ABSTRACT: An extensive base of water quality information emphasizing the effects of land use and hydrology was obtained in the karstified Fountain Creek watershed of southwestern Illinois to help resolve local water quality issues. Agrichemicals dominate the loads of most water quality constituents in the streams and shallow karstic ground water. Only calcium (Ca), magnesium (Mg), Aluminum (A1), and sulfate (SO₄) ions are predominantly derived from bedrock or soils, while agrichemicals contribute most of the sodium (Na), potassium (K), chlorine (Cl), nitrate (NO₃), fluorine (F), phosphorus (P), and atrazine. Concentrations of individual ions correlate with discharge variations in karst springs and surface streams; highly soluble ions supplied by diffuse ground water are diluted by high flows, while less soluble ions increase with flow as they are mobilized from fields to karst conduits under storm conditions. Treated wastewater containing detergent residues dominates the boron load of streams and provides important subordinate loads of several other constituents, including atrazine derived from the Mississippi River via the public water supply. Average surface water concentrations at the watershed outlet closely approximate a 92:8 mixture of karst ground water and treated wastewater, demonstrating the dominance of ground water contributions to streams. Therefore the karst aquifer and watershed streams form a single water quality system that is also affected by wastewater effluent.     

Material flow analysis of lubricating oil use in California

Petroleum lubricating oils, used throughout the economy, are distinct among petroleum products in their capacity to be recovered and recycled at the end of their useful life. Used lubricating oil is regulated at the state and federal level because of concerns about environmental impacts arising from improper disposal, although rates of recovery are not known. We present a material flow analysis of lubricants through California's economy in the years 2007–2012. We introduce a novel technique for computing aggregate waste generation from a collection of hazardous waste manifest records, and apply it in order to determine a recovery rate for used oil and to estimate the quantity of oil managed informally in the state. The records also offer a detailed view of the fate of used oils after they are recovered. We find that around 62% of lubricants are recoverable at end of life, of which 70–80% is being recovered. This rate shows a slight downward trend. If the trend is accurate, measures should be taken to improve the performance of the used oil management system. Policy opportunities exist to reduce the quantity of oil managed informally through improving access to responsible used oil management methods. These include increasing the collection of used oil from industrial sources as well as “do it yourself” oil changes, expanding in-state reprocessing capacity, and promoting increased out-of-state reprocessing of used oil. Our methods introduce new possibilities to make use of direct observation in material flow analysis, potentially improving data availability and quality and increasing the relevance of material flow methods in policy applications.     

Investigation of multiple domino scenarios caused by fragments

A model of multiple domino scenarios and the risk of the domino effect, which is a sequential chain escalating from the primary unit to the last unit, is presented in this paper. The trajectories of fragments from all units, the ground distribution of projectiles, and the risk of the sequential chain of the domino effect were calculated using Monte Carlo simulations. The results showed that the range affected by the fragments from each tank included the other tanks, meaning that fragments from one tank could hit the other tanks and cause multiple accidents, and that the sequential chain of the domino effect could indeed happen. The distributions of ground impacts showed that tank fragments were projected over long distances, up to 1200 m from the source. The spatial distribution of the kinetic energy at ground impact for tank fragments was also obtained. Moreover, the magnitudes of the probabilities of the primary, secondary, third, and fourth accidents in the domino chain were respectively about 10⁻⁷, 10⁻¹¹, 10⁻¹⁵, and 10⁻¹⁹. These results showed that for neighboring domino effect units in the same accident chain, the risk of the most recent domino effect was 10⁴ times that of the following domino effect.     

疫情下医疗废物的处置现状分析

2019年新冠疫情席卷全球,在疫情环境下,医疗废物大幅增多,全国各大城市纷纷出现医疗废物处置不当的现象。本文对国内外现状分析,在认知、设施、管理和监督四个方面发现存在一定的问题,通过加强教育、加大储备、完善机制和改善监管的建议,为提升医疗废物应急处置能力提供参考。     

Metal distribution characteristic of MSWI bottom ash in view of metal recovery

Bottom ash is the major by-product of municipal solid waste incineration(MSWI), and is often reused as an engineering material, such as road-base aggregate. However, some metals(especially aluminum) in bottom ash can react with water and generate gas that could cause expansion and failure of products containing the ash; these metals must be removed before the ash is utilized. The size distribution and the chemical speciation of metals in the bottom ash from two Chinese MSWI plants were examined in this study, and the recovery potential of metals from the ash was evaluated. The metal concentrations in these bottom ashes were lower than that generated in other developed countries. Specifically, the contents of Al,Fe, Cu and Zn were 18.9–29.2, 25.5–32.3, 0.7–1.0 and 1.6–2.5 g/kg, respectively. Moreover,44.9–57.0 wt.% of Al and 55.6–75.4 wt.% of Fe were distributed in bottom ash particles smaller than 5 mm. Similarly, 46.6–79.7 wt.% of Cu and 42.9–74.2 wt.% of Zn were concentrated in particles smaller than 3 mm. The Fe in the bottom ash mainly existed as hematite, and its chemical speciation was considered to limit the recovery efficiency of magnetic separation.     

Performance and microbial community of a membrane bioreactor system——Treating wastewater from ethanol fermentation of food waste

In this study, a lab-scale biological anaerobic/anaerobic/anoxic/membrane bioreactor(A_-~3MBR) was designed to treat wastewater from the ethanol fermentation of food waste,a promising way for the disposal of food waste and reclamation of resources. The 454 pyrosequencing technique was used to investigate the composition of the microbial community in the treatment system. The system yielded a stable effluent concentration of chemical oxygen demand(202 ± 23 mg/L), total nitrogen(62.1 ± 7.1 mg/L), ammonia(0.3 ±0.13 mg/L) and total phosphorus(8.3 ± 0.9 mg/L), and the reactors played different roles in specific pollutant removal. The exploration of the microbial community in the system revealed that:(1) the microbial diversity of anaerobic reactors A_1 and A_2, in which organic pollutants were massively degraded, was much higher than that in anoxic A_3 and aerobic MBR;(2) although the community composition in each reactor was quite different, bacteria assigned to the classes Clostridia, Bacteroidia, and Synergistia were important and common microorganisms for organic pollutant degradation in the anaerobic units, and bacteria from Alphaproteobacteria and Betaproteobacteria were the dominant microbial population in A_3 and MBR;(3) the taxon identification indicated that Arcobacter in the anaerobic reactors and Thauera in the anoxic reactor were two representative genera in the biological process. Our results proved that the biological A_-~3MBR process is an alternative technique for treating wastewater from food waste.     

添加动物源氨基酸水解液研制生物有机肥

为改善生物有机肥性质,提高生物有机肥质量,采取在生物有机肥中添加外源氨基酸水解液以提升生物有机肥中功能微生物的数量.以病死猪酸解制得氨基酸水解液为生物有机肥外加原料,研究了氨基酸水解液添加量、有机肥种类（鸡粪、牛粪、中药渣）、发酵时间对功能菌株SQR9数量的影响.结果表明:当氨基酸水解液添加量为20%时固体发酵效果优于其他接种量,预发酵3 d后接种SQR9的功能菌数量明显高于未预发酵直接接菌,预发酵中肥料（以干质量计,下同）的最高功能菌数量可达4×108 CFU/g,而第0天接菌时肥料的最高功能菌数量仅为1.2×108 CFU/g.以腐熟鸡粪、牛粪、中药渣堆肥为载体,添加酸解氨基酸研制生物有机肥的最优接菌量分别为10.0%、7.5%、10.0%;SQR9菌株生长的最佳含水量为40%.此外,氨基酸水解液的添加可提高生物有机肥的w（TN）.研究显示,氨基酸水解液的添加能有效促进固态发酵过程中功能菌株数量的增加.      

低碳经济背景下我国产业结构升级对策研究

为了实现我国经济的平稳发展,改变以"高消耗、高增长、高污染"的传统经济增长方式,解决资源的过度消耗和温室气体的过量排放等问题,文章从我国产业及内部结构、产业的碳排放量和产业节能率三个方面进行了分析,提出了在低碳经济背景下实现我国产业结构升级的对策。     

我国工业危险废物的来源、处理及监管对策与建议

通过大量环境统计数据的分析,对我国工业危险废物的产生、综合利用、处置和贮存,从行业来源、区域分布进行了分析和总结。结合我国工业危险废物企业自建设施和政府集中处理设施处理情况,对我国工业危险废物的处理和环保监管对策提出了若干建议。