Salt enrichment of municipal sewage: New prevention approaches in Israel

Wastewater irrigation is an environmentally sound wastewater disposal practice, but sewage is more saline than the supplied fresh water and the salts are recycled together with the water. Salts have negative environmental effects on crops, soils, and groundwater. There are no inexpensive ways to remove the salts once they enter sewage, and the prevention of sewage salt enrichment is the most immediately available solution. The body of initiatives presently structured by the Ministry of the Environment of Israel are herein described, with the aim to contribute to the search for a long-term solution of salinity problems in arid countries. The new initiatives are based on: (1) search for new technologies to reduce salt consumption and discharge into sewage; (2) different technologies to cope with different situations; (3) raising the awareness of the public and industry on the environmental implications of salinity pollution; and (4) an elastic legal approach expressed through new state-of-the-art regulations. The main contributor to the salinity of sewage in Israel is the watersoftening process followed by the meat koshering process. Some of the adopted technical solutions are: the discharge of the brine into the sea, the substitution of sodium by potassium salts in the ion-exchangers, the construction of centralized systems for the supply of soft water in industrial areas, the precipitation of Ca and Mg in the effluents from ion-exchangers and recycling of the NaCI solution, a reduction of the discharge of salts by the meat koshering process, and new membrane technology for salt recovery.     

工业雷管意外起爆的防范研究

工业雷管在生产、贮运、使用过程中存在意外发火或爆炸事故。为了防止这种突然事件和避免带来的伤害与损失，笔者就可能导致意外起爆的各种原因进行了分析，提出了各种相应的防范措施和意见     

抚顺市重点工业企业能源消耗及污染物排放分析

利用能源生产和使用的生命周期清单分析数据库提出的标准化数据,重点分析抚顺市主要能源及产品生产过程中的能源消耗及污染物排放,从而为重点行业的节能降耗、防治污染提供依据。     

Improved Bankfull Discharge Prediction Using 2‐Year Recurrence‐Period Discharge1

Abstract:  Knowledge of bankfull discharge (Q_bf) is essential for planners, engineers, geomorphologists, environmentalists, agricultural interests, developments situated on flood prone lands, surface mining and reclamation activities, and others interested in floods and flooding. In conjunction with estimating Q_bf, regionalized bankfull hydraulic geometry relationships, which relate Q_bf and associated channel dimensions (i.e., width, depth, and cross‐section area) to drainage basin area (A_da), are often used. This study seeks to improve upon the common practice of predicting Q_bf using A_da exclusively. Specifically, we hypothesize that predictions of Q_bf can be improved by including estimates of the 2‐year recurrence‐period discharge (Q₂) in regression models for predicting Q_bf. For testing this hypothesis, we used Q_bf estimates from 30 reports containing data for streams that span 34 hydrologic regions in 16 states. Corresponding values of Q₂ and A_da were compiled from flood‐frequency reports and other sources. By comparing statistical measures (i.e., root mean squared error, coefficient of determination, and Akaike’s information criterion), we determined that predicting Q_bf from Q₂ rather than A_da yields consistently better estimates of Q_bf. Other principal findings are (1) data are needed for at least 12 sites in a region for reliable hydraulic geometry model selection and (2) an approximate range of values for Q_bf/Q₂ is 0.10‐3.0.     

低温等离子体治理恶臭气体研究进展

介绍了恶臭气体的分类和来源、传统的除臭方法以及这些方法的缺点；简述了低温等离子体产生的方法及其治理恶臭气体的机理；论述了介质阻挡放电、脉冲电晕放电、滑动弧光放电和其他方法在除臭方面的国内外研究进展；指出了利用等离子体治理恶臭气体存在的主要问题及其今后的研究方向。     

气液混合脉冲放电体系中偶氮染料的脱色效果

为了深入探究水包气式气液混合脉冲放电体系中各参数对有机物降解效果的影响，建立了多针一板电极形式的气液混合脉冲放电等离子体体系，以典型的偶氮染料——酸性橙Ⅱ（A07）为目标物，考察该体系中影响染料脱色效果的关键因素。研究结果表明，气液混合脉冲放电体系中与脉冲电源输入功率有关的因素（脉冲电压峰值和脉冲频率）对A07脱色效果影响明显。随着脉冲电压峰值和脉冲频率的增加，A07溶液的脱色效率和相应的准一级降解动力学常数增加。在较高的脉冲电压峰值（30kV）和脉冲频率（75Hz）条件下，10mg／LA07溶液的脱色效率和准一级降解动力学常数分别达到r92．7％和3．50×10～／min。同时，研究证明酸性溶液条件较利于染料脱色。     

介质阻挡放电常压降解哈隆的研究

本文以介质阻挡放电的方式产生低温等离子体，利用低温等离子体技术成功地降解了常压状况下的气态ＣＦ２ＣｌＢｒ，ＣＦ２ＣｌＢｒ含量为０．６％的空气在放电１０ｓ的条件下，可使ＣＦ２ＣｌＢｒ达到９５％的降解率。本文研究了常压状况下的ＣＦ２ＣｌＢｒ低温等离子体空间反应机理，以及ＣＦ２ＣｌＢｒ初妈压力，电场强度和外加气体分别对低温等离子体降解ＣＦ２ＣｌＢｒ的影响。     

火电厂离子交换树脂再生废水处理及减排

针对火电厂离子交换树脂再生废水中和处理过程中遇到的问题，探讨影响中和处理的因素，并提出减少火电厂离子交换树脂再生废水排放的措施.     

无组织排放监测技术研讨

为了获取无组织排放源被测物质在环境中的最高浓度值,公正地判定被测企业排放源对环境中被测物质浓度贡献的大小,监测人员要依据相关标准和技术导则,正确设置监测点位、选择合适监测时间,以确保监测数据的有效性。     

放电条件下SF5CF3的分解反应

SF₅CF₃是近年被发现的具有强红外辐射强迫、长寿命的新温室气体.本文利用火花放电技术模拟研究了放电条件下SF₅CF₃的去除机理.结果表明,SF₅CF₃在放电过程中将被分解并生成多种含硫、氟、氧和碳的化合物.H₂O的存在能够降低SF₅CF₃的分解速率,但降低的量与H₂O的分压无关. 在有H₂O存在的条件下,当体系总压约为31kPa时,闪电过程中SF₅CF₃的分解速率常数分别为0.011s^-.同时,SF₅CF₃的分解率随着体系的总压上升而呈指数下降.基于实验结果,对SF₅CF₃在放电过程中的反应途径作了探讨,并估算实际大气中放电的一种形式--闪电所引起的SF₅CF₃的分解量为53.6 kg·a^-.