微动力接触氧化法处理军营生活污水示范研究

将改变传统的机械充氧方式,通过增加水体与空气的接触面积,延长接触时间,进行自然充氧应用于微动力接触氧化法处理生活污水上。重点研究跌水曝气与接触氧化的耦合关系、停留时间与曝气量的耦合关系,形成跌水曝气接触氧化微动力分散式污水处理技术,研究微动力接触氧化挂膜规律和快速挂膜方法。并通过对技术参数的优化,在达到溶氧要求的同时,简化设计,提高其与后续工艺的对接性,降低工艺难度。     

小微景观水体治理技术探讨

小微景观水体环境容量小,自净能力低,易出现水质浑浊、藻类爆发等现象。常见的治理技术包括物理治理技术、化学治理技术和生物修复技术。在实际治理过程中,应采用多技术联用的综合治理方法,才能实现改善水质、恢复生态平衡、美化水景的目标。     

固相微萃取技术及其在环境监测中的应用

介绍了90年代初推出的一种新的样品前处理技术－固相微萃取技术。它与传统的萃取法相比具有分析周期短、简捷、灵敏度高,无须使用溶剂,适于现场监测等优点,目前已成功地用于各基质样品如：土壤、水、大气中环境污染物的分析。文章还对其基本原理、固相涂层、操作模式展开了讨论。经分析认为该技术有着广阔的推广和应用前景。     

混凝微滤法处理制革废水

对混凝微滤法处理制革废水进行了试验研究,通过大量试验,确定了最佳工艺条件。在最优控制的基础上,制革废水经混凝沉淀－微滤处理后,COD,BOD5,SS和色度的去除率分别为80%,87%,89%和92%左右,处理后废水可达到排放标准或回用于制革工艺。结果表明,在较低温度下,用硫酸亚铁作混凝剂仍能较好地完成混凝沉淀,验证了硫酸亚铁的低温混凝效果。因此,该工艺值得在北方寒冷地区大力推广。      

Safety analysis and risk assessment of a Micro-GtL Plant

Laboratory hydrogen generators, medical oxygen, and micro-breweries are examples of modular and micro technologies that are commercial successes. Researchers, patients, and unskilled workers operate these facilities but more complex processes require highly qualified personnel to ensure they operate safely. Modular-micro processes in isolated locations meet economic objectives when operated remotely thereby minimizing labor costs. Mitigating the risk requires a comprehensive hazards analysis with advanced control systems particularly for explosive and toxic compounds. Here, we propose a method called Failure Mode Risk Decision (FMRD) to review the inherent hazards of a micro-refinery unit (MRU) that converts flared and wasted natural gas to long chain hydrocarbons. This approach combines the Process Flow Failure Mode (PFFM) methodology as a systematic and reliable technique with a novel numerical risk assessment to improve the analytical evaluation of hazardous conditions. The objective is to combine causes and consequences in a single metric, where scaled probability of evident causes and severity of consequences are used to derive a risk level measure. With the proposed metric, the magnitude of a potential hazard is directly correlated with the risk level. This mechanism identifies extra risk scenarios compared to the classical hazard analysis method and provides a straightforward comprehensive numerical assessment to represent the inherent and residual risks to facilitate justifying the hazardous scenarios. Accordingly, we design a safety loop and supply all the required facilities to remove the potential risks at the process plant. Not only the proposed methodology clarifies the risks of the MRU presented in this study, but can be extended to review the hazards of other chemical process plants.     

High technology firms and planning policy: a case study of research machines limited,Oxford

This article reviews planning issues relating to “high‐tech” industry in Britain, and uses a case study of a manufacturer of micro‐computers in Oxford, England as a focus for a discussion. It concludes that town planning categories are not, in themselves, a constraint on high technology firms, and suggests that the provision of sites and premises by local authorities is a useful and undervalued task.     

染料废水的内电解脱色处理研究

采用铁屑内电解法对５大类１１种模拟染料废水和印染废水进行了内电解混凝处理，得出了内电解法处理染料废水的最佳工艺条件，探讨了脱色机理，并在实际印染废水处理工程中得到有效应用。研究表明，对中等色度和浓度的模拟染料废水，脱色率均在７７％以上，在实际印染废水处理工程中采用混凝和内电解联合处理工艺，脱色率可达９６％以上。     

Impacts of sodium hydroxide and sodium hypochlorite aging on polyvinylidene fluoride membranes fabricated with different methods

This study compared the effects of chemical aging on the polyvinylidene fluoride(PVDF)membranes fabricated with the methods of non-solvent induced phase separation(NIPS)(named NIPS-PVDF) and thermally induced phase separation(TIPS)(named TIPS-PVDF). The chemical solutions of sodium hypochlorite(NaClO) and sodium hydroxide(NaOH) were chosen at the concentration of 5000 mg/L. The equivalence of 5 and 10 years was respectively selected as the time of aging. The physicochemical evolutions of membrane aging are characterized on the base of morphology analysis, chemical components, permeation ability and mechanical properties. The aging of NIPS-PVDF membrane led to the elimination of surface hydrophilic additives, while NaO H focused on the dehydrofluorination process resulting in the formation of conjugated chains of polyene on the skeleton structure. The chemical components of the surface of TIPS-PVDF membrane were removed continuously during the aging processes of both NaClO and NaOH, which was caused by the saponification of surface additives and the chain scissions of skeleton structure, but without producing any obvious conjugated chains of polyene. All the aging processes led to the increase of contact angle and the decrease of mechanical properties, and the permeability was reduced first and increased later due to the enlargement of surface membrane pores and membrane block. With the influence of membrane aging, selectivity of membrane was decreased(except coliform bacteria). At the beginning of filtration, the turbidity and particle count were at relatively high levels and declined with the filtration process.     

Environmental sampling of volatile organic compounds during the 2018 Camp Fire in Northern California

Trace analysis of volatile organic compounds (VOCs) during wildfires is imperative for environmental and health risk assessment. The use of gas sampling devices mounted on unmanned aerial vehicles (UAVs) to chemically sample air during wildfires is of great interest because these devices move freely about their environment, allowing for more representative air samples and the ability to sample areas dangerous or unreachable by humans. This work presents chemical data from air samples obtained in Davis, CA during the most destructive wildfire in California's history - the 2018 Camp Fire – as well as the deployment of our sampling device during a controlled experimental fire while fixed to a UAV. The sampling mechanism was an in-house manufactured micro-gas preconcentrator (µPC) embedded onto a compact battery-operated sampler that was returned to the laboratory for chemical analysis. Compounds commonly observed in wildfires were detected during the Camp Fire using gas chromatography mass spectrometry (GC–MS), including BTEX (benzene, toluene, ethylbenzene, m+p-xylene, and o-xylene), benzaldehyde, 1,4-dichlorobenzene, naphthalene, 1,2,3-trimethylbenzene and 1-ethyl-3-methylbenzene. Concentrations of BTEX were calculated and we observed that benzene and toluene were highest with average concentrations of 4.7 and 15.1 µg/m³, respectively. Numerous fire-related compounds including BTEX and aldehydes such as octanal and nonanal were detected upon experimental fire ignition, even at a much smaller sampling time compared to samples taken during the Camp Fire. Analysis of the air samples taken both stationary during the Camp Fire and mobile during an experimental fire show the successful operation of our sampler in a fire environment.