Emergy-based assessment on industrial symbiosis: a case of Shenyang Economic and Technological Development Zone

Industrial symbiosis is the sharing of services, utility, and by-product resources among industries. This is usually made in order to add value, reduce costs, and improve the environment, and therefore has been taken as an effective approach for developing an eco-industrial park, improving resource efficiency, and reducing pollutant emission. Most conventional evaluation approaches ignored the contribution of natural ecosystem to the development of industrial symbiosis and cannot reveal the interrelations between economic development and environmental protection, leading to a need of an innovative evaluation method. Under such a circumstance, we present an emergy analysis-based evaluation method by employing a case study at Shenyang Economic and Technological Development Zone (SETDZ). Specific emergy indicators on industrial symbiosis, including emergy savings and emdollar value of total emergy savings, were developed so that the holistic picture of industrial symbiosis can be presented. Research results show that nonrenewable inputs, imported resource inputs, and associated services could be saved by 89.3, 32.51, and 15.7 %, and the ratio of emergy savings to emergy of the total energy used would be about 25.58 %, and the ratio of the emdollar value of total emergy savings to the total gross regional product (GRP) of SETDZ would be 34.38 % through the implementation of industrial symbiosis. In general, research results indicate that industrial symbiosis could effectively reduce material and energy consumption and improve the overall eco-efficiency. Such a method can provide policy insights to industrial park managers so that they can raise appropriate strategies on developing eco-industrial parks. Useful strategies include identifying more potential industrial symbiosis opportunities, optimizing energy structure, increasing industrial efficiency, recovering local ecosystems, and improving public and industrial awareness of eco-industrial park policies.     

转轮式洗轮机对车轮带泥的冲洗效果

施工车辆车轮带泥是我国道路扬尘污染控制面临的共性和突出问题。为在国内推广使用洗轮机提供技术依据，通过检测工地出口外道路积尘负荷来估算转轮式洗轮机对车轮带泥的冲洗效率，并以该洗轮机作为车轮带泥检测设备，检测和统计北京市车轮带泥量。结果表明，（1）转轮式洗轮机可以将工地出口外100m道路积尘负荷增量由64．4g／m2降至5．9g／m2，转轮式洗轮机对车轮带泥的冲洗效率大于90％；（2）渣土车和混凝土车车轮带泥量的平均值分别为5．1和2．2kg／车；（3）北京市未来车轮带泥量将超过8．8万t／a，施工车辆全部经过转轮式洗轮机冲洗后，车轮带泥量可削减7．9万t／a。建议在相关法律法规中以强制性条款落实施工车辆车轮带泥机械化冲洗要求。     

某铀尾矿库区周围稻田土壤不同组分对U(Ⅵ)的吸附性能分析

通过斯笃克定律提取土壤胶体,连续提取法吸附土壤中的有机质,得到土壤矿质胶体,采用比表面积(BET)法和Zeta电位对原土、土壤胶体和矿质胶体进行了表征分析,考察了溶液pH、接触时间、U(Ⅵ)初始浓度以及温度等因素对3种样品吸附溶液中U(Ⅵ)的影响性能。结果表明:原土、土壤胶体和矿质胶体的比表面积和平均孔径分别为11.5,31.1,28.8 m2/g和18.76,35.55,17.5 nm。在pH为5.5,固液比在1.0 g/L,温度为20 ℃,U(Ⅵ)初始浓度为10.0 mg/L,土壤、土壤胶体反应时间为50 min,矿质胶体反应时间为40 min时,原土、土壤胶体、矿质胶体的对U(Ⅵ)吸附率分别达到76.67%、83.03%、48.87%,吸附容量分别达到8.53,9.24,5.43 mg/g。对比研究结果可以看出,土壤中的胶体对溶液中U(Ⅵ)有着明显的吸附能力,该研究结果对进一步研究含U(Ⅵ)废水的处理及U(Ⅵ)在土壤和地下水中的迁移过程有一定的参考意义。     

HSE管理体系运行中的常见问题及对策

分析了HSE管理体系运行中存在的问题,提出了对策措施。     

CaCu3Ti4O12, an efficient catalyst for ibuprofen removal by activation of peroxymonosulfate under visible-light irradiation

Environmental Chemistry Letters - Contamination of waters by pharmaceuticals is a major health issue. Therefore, there is a need for efficient techniques to remove pharmaceutical pollutants. Here,...     

Generation and distribution of PAHs in the process of medical waste incineration

After the deadly earthquake on May 12, 2008 in Wenchuan county of China, several different incineration approaches were used for medical waste disposal. This paper investigates the generation properties of polycyclic aromatic hydrocarbons (PAHs) during the incineration. Samples were collected from the bottom ash in an open burning slash site, surface soil at the open burning site, bottom ash from a simple incinerator, bottom ash generated from the municipal solid waste (MSW) incinerator used for medical waste disposal, and bottom ash and fly ash from an incinerator exclusively used for medical waste. The species of PAHs were analyzed, and the toxicity equivalency quantities (TEQs) of samples calculated. Analysis results indicate that the content of total PAHs in fly ash was 1.8 × 10³ times higher than that in bottom ash, and that the strongly carcinogenic PAHs with four or more rings accumulated sensitively in fly ash. The test results of samples gathered from open burning site demonstrate that Acenaphthylene (ACY), Acenaphthene (ACE), Fluorene (FLU), Phenanthrene (PHE), Anthracene (ANT) and other PAHs were inclined to migrate into surrounding environment along air and surface watershed corridors, while 4- to 6-ring PAHs accumulated more likely in soil. Being consistent with other studies, it has also been confirmed that increases in both free oxygen molecules and combustion temperatures could promote the decomposition of polycyclic PAHs. In addition, without the influence of combustion conditions, there is a positive correlation between total PCDD/Fs and total PAHs, although no such relationship has been found for TEQ.     

Electrodialytic soil remediation enhanced by low frequency pulse current – Overall chronopotentiometric measurement

The effect of low frequency pulse current on decreasing the polarization and energy consumption during the process of electrodialytic soil remediation was investigated in the present work. The results indicated that the transportation of cations through the cation exchange membrane was the rate controlling step both in constant and pulse current experiments, thus responsible for the major energy consumption. After 180 h, a decrease in both the initial ohmic resistance in each pulse cycle and the resistance caused by concentration polarization of the anion exchange membrane were seen in the pulse current experiment compared to the constant current experiment. At the cation exchange membrane, only the resistance caused by concentration polarization decreased. In the soil compartment, an average of +60 mV overpotential caused by the polarization of the electric double layer of the clay particles was obtained from the Nernstian behavior simulation of the relaxation process, which was significantly lower than the ohmic voltage drop induced by pore fluid resistance. Therefore, the ohmic polarization was the major contributor to the energy consumption in the soil compartment and diminished by pulse current.     

循环荷载作用下三明治形加筋土挡墙的模型试验与数值模拟∗

为研究循环荷载作用下三明治形加筋土挡墙的受力特性,进行了一系列砂土加筋土挡墙和三明治形加筋土挡墙的动加载室内模型试验.针对不同的加载特征,分析加筋土挡墙的变形和应力响应.采用FLAC3D建立三明治形加筋土挡墙的数值计算模型,通过与模型试验的对比,验证了计算模型的可靠性,分析了循环荷载下挡墙的变形、加速度和潜在破裂面.研究结果表明:三明治形加筋土挡墙变形与竖向土压力随荷载幅值、荷载频率和激振器个数的增加而增大;荷载对土压力的影响随距振源距离的增大而减小;相同加载条件下,三明治形挡墙的顶部沉降更大;随着挡墙高度的增加,土压力的振动幅值逐渐增大,土压力峰值减小;挡墙沉降并非成层均匀沉降,内部分层沉降出现双峰值;随墙高减小加速度衰减,加速度峰值在挡墙上部的平均衰减率最大;三明治形加筋土挡墙与砂土加筋土挡墙破裂面位置相近.地面交通荷载引起的振动对挡墙结构产生不利影响是加筋挡墙的研究重点.     

构建三元混合污染物的三维等效图

等效线分析法广泛应用于二元混合物的毒性相互作用评估.然而,如何构建三维等效图以考察三元混合物中发生的毒性相互作用至今没有文献报道.本研究的主要目的即以三元混合物中3个组分的相对浓度为坐标轴建立三维等效图以考察三元混合物的毒性相互作用.以6种目前在中国广泛使用的农药,包括3种除草剂(2,4-D、敌草净、西草净)和3种杀虫剂(乐果、吡虫啉、残杀威)为混合物组分,采用均匀设计射线法(UD-Ray)分别对三元除草剂和三元杀虫剂混合物中各组分浓度分布进行优化设计,以全面表征实际混合物的浓度多样性.通过费氏弧菌微板毒性分析法测定农药及其三元混合物在不同浓度下的发光抑制毒性,以浓度加和(CA)模型为加和参考模型,建立三维等效图,分析各混合物的毒性相互作用.结果表明,三维等效图能清晰、直观地反映三元混合物的毒性相互作用信息,开拓等效分析法在三元混合物毒性分析中的应用.