工业园区生态化的产业共生体系研究——以天津空港经济区为例

工业园区生态化是未来发展的必然选择,其核心是建立"资源—产品—消费—再生资源"产业共生的生态模式,以充分利用资源、减缓或消除环境破坏、协调社会经济与资源环境的关系。在工业园区生态化发展需求及趋势分析的基础上,以产业生态学理论为指导,分析了工业园区生态产业链及产业共生模式的类别及特征。并以天津空港经济区为例,构建了嵌套型工业共生体系框架。     

工业园区固体废物资源化技术研究

工业园区固体废物资源化是实施循环经济、建设生态文明的关键一环,但在实施过程中遇到诸多问题.以工业园区固体废物外延的重新界定为起点,从3个方面分析了工业园区固体废物资源化技术:固体废物生态产业链构建与运行维护、回收与分类技术、再利用与循环技术,并就固体废物资源化方面存在的问题提出了相应的解决建议.     

我国工业园区发展循环经济的问题及对策研究

工业园区发展循环经济对于促进工业园区的可持续发展意义重大.首先对工业园区发展循环经济的必要性进行论述,在此基础上,分析了我国工业园区循环经济发展的现状和发展过程中存在的问题,最后从工业园区企业的准入、传统工业园区的生态化改造、提升工业园区的产业价值链,以及构建绿色产品市场体系和绿色产品信息网络等方面提出了相应的对策建议.     

以煤化工和盐化工为基础发展循环经济

以内蒙古庆华集团的煤化工和中盐兰太集团的盐化工为中心,以相互之间综合利用对方目前产业的中间产品、产品,生产过程中排出的废气、废渣为目的,通过煤盐化工的联合发展,形成相互之间为依托,可以大力发展精细化工,有效延长各自产业链,提高产品附加值,实现煤化工、盐化工传统产业的结构调整和产业升级,切实提高企业的经济效益,同时也兼顾了工业园区其他相关企业发展,实现整个工业园区的产业结构调整与升级。     

废钢破碎线收益能力分析

废钢破碎线是金属资源回收企业的核心生产工艺之一,以废金属和报废汽车等为加工原料,以破碎和分选为核心工艺,是金属回收产业的重要组成部分。作为衔接金属资源回收和金属冶炼产业链的重要环节,废钢破碎线的收益能力是金属资源回收企业提升收益能力、降低运营成本的关键因素。对废钢破碎线的收益能力和影响收益能力的各因素进行分析,构建出函数模型,基于函数模型分析,得出金属资源回收企业在废钢破碎线的筹划、选型、投建、使用、运营维护和管理等方面应该重视的因素。其分析结果为废钢回收企业和报废汽车回收企业投资建设提供参考。     

京津冀协同视角下再生资源产业链构建研究

以京津冀地区为例,根据再生资源产业链的构建原则从资源消耗、产业规模和创新能力3个层面构建评价体系并运用区位熵法确定区域内关键产业,按照"构建跨区域产业链主链—产业链补链—产业链耦合"的思路,构建了京津冀区域钢铁、生物医药、石油化工和煤炭固废综合利用产业链达到了纵向角度系统性对再生资源产业链运行分析的目的,以期促进京津冀再生资源产业协同发展。     

有火电特色的循环经济型生态工业园研究

介绍了生态工业园的概念,结合我国电力工业发展现状,阐述了建立有火电特色的循环经济型生态工业园的重要性和现实性.结合包头、卡伦堡和布朗斯维尔案例,分析了火电基础型、火电核心型和火电虚拟型三种典型生态工业园模式.从产品、企业和园区三个层次,探讨了工业园区的生态管理,以期为我国生态工业园理论研究的深化和实践的深入提供参考.     

关于钢铁企业建设生态工业园的思考与建议

生态工业园是一种新型工业组织形态,是根据循环经济理论和工业生态学原理建立的一种与生态环境和谐共存的新型工业园区。论述了钢铁企业在搞好企业内部循环经济的基础上,向生态工业园发展的必要性;提出建设以钢铁企业为核心的生态工业园的三种模式;并对钢铁企业如何适时有效地发展生态工业园提出建议。     

基于价值网络构建的再生资源企业商业模式创新

在传统产业链视角下,再生资源企业往往面临自身竞争力不强、行业竞争激烈以及上下游压榨等难题。而从价值网络构建角度出发,对再生资源回收利用以及环卫、环保等相关产业关系进行重构,创新企业经营理念和实践模式,能够给传统再生资源行业的产业结构、运行模式、运行效率等带来变革式的影响。分析了产业链视角下再生资源产业的困境,并在阐述价值网络理论的基础上,提出对于再生资源产业运行的启示。以桑德集团有限公司为例,分析了其在构建、主导和运行资源环境价值网络中的做法与成效,最后提出资源环境价值网络未来发展的侧重点。     

分布式供能系统与上海世傅会的低碳节能环保建设

分布式供能系统是指以小规模、小容量、模块化、分散式的方式布置在用户附近,同时提供电力、热水等多种能源的高效能源供应系统,其主要技术形式为热电联供.热气机又被称为斯特林机,是一种多燃料、低噪声、可热电联供的原动机.上海世博会热气机热电联供系统以天然气为燃料,可同时向世博园区内某餐饮中心提供50 kw电力和1.5 gh热水.热气机热电联供系统在上海世博展会期间的成功运行,为上海世博会的低碳节能环保建设和新能源应用,以及分布式供能系统建设作出了贡献.     

Determination of the Thermal Efficiency of Pre-boilover Burning of a Slick of Oil on Water

The burning rate of a slick of oil on a water bed is calculated by a simple expression derived from a one-dimensional heat conduction equation. Heat feedback from the flame to the surface is assumed to be a constant fraction of the total energy released by the combustion reaction. The constant fraction (χ) is named the burning efficiency and represents an important tool in assessing the potential of in situ burning as a counter-measure to an oil-spill. The total heat release, as a function of the pool diameter, is obtained from an existing correlation. It is assumed that radiative heat is absorbed close to the fuel surface, that conduction is the dominant mode of heat transfer in the liquid phase and that the fuel boiling temperature remains constant. By matching the characteristic thermal penetration length scale for the fuel/water system and an equivalent single layer system, a combined thermal diffusivity can be calculated and used to obtain an analytical solution for the burning rate. Theoretical expressions were correlated with crude oil and heating oil, for a number of pool diameters and initial fuel layer thickness. Experiments were also conducted with emulsified and weathered crude oil. The simple analytical expression describes well the effects of pool diameter and initial fuel layer thickness permitting a better observation of the effects of weathering, emulsification and net heat feedback to the fuel surface. Experiments showed that only a small fraction of the heat released by the flame is retained by the fuel layer and water bed (of the order of 1%). The effect of weathering on the burning rate decreases with the weathering period and that emulsification results in a linear decrease of the burning rate with water content.     

Calculation of carbon balances for evaluation of the biodegradability of polymers

Establishing carbon balances has been proven to be an applicable and powerful tool in testing biodegradability of polymers. In controlled degradation tests at a 4-L scale with the model polymer poly(-hydroxybutyrate) (PHB), it was shown that the degree of degradation could not be determined with satisfactory accuracy from CO₂ release alone. Instead, the course of degradation was characterized by means of establishing carbon balances for the degradation of PHB withAcidovorax facilis and a mixed culture derived from compost. Different analytical methods for determining the different carbon fractions were adapted to the particular test conditions and compared. Quantitative determination of biomass and residual polymer were the main problems in establishing carbon balances. Amounts of biomass derived from protein measurements depend strongly on assumptions of the protein content of the biomass. Selective oxidation of biomass with hypochlorite was used as alternative, but here problems arose from insoluble metabolic products. Determination of soluble components with the method of chemical oxygen demand (COD) also includes empirical assumptions but seems acceptable if the dissolved carbon fraction is in the range of some 10% total carbon. Results confirm both analytical assays and theoretical approaches, in ending up at values very close to 100%, within an acceptable standard deviation range under test conditions comparable to standard test practice.Paper presented at the Bio/Environmentally Degradable Polymer Society—Third National Meeting, June 6–8, 1994, Boston, Massachusetts.     

富拉尔基发电总厂200MW机组除尘器改造

对富拉尔基发电总厂5号炉的设计条件进行了分析，针对燃用低硫煤，飞灰比电阻高，场地较小，除尘效率要求高的情况，在电除尘器的设计上采取有效措施，达到了排放要求。     

Review of the kinetics of alkaline degradation of cellulose in view of its relevance for safety assessment of radioactive waste repositories

The degradation of cellulose (a substantial component of low- and intermediate-level radioactive waste) under alkaline conditions occurs via two main processes: a peeling-off reaction and a basecatalyzed cleavage of glycosidic bonds (hydrolysis). Both processes show pseudo-first-order kinetics. At ambient temperature, the peeling-off process is the dominant degradation mechanism, resulting in the formation of mainly isosaccharinic acid. The degradation depends strongly on the degree of polymerization (DP) and on the number of reducing end groups present in cellulose. Beyond pH 12.5, the OH^- concentration has only a minor effect on the degradation rate. It was estimated that under repository conditions (alkaline environment, pH 13.3-12.5) about 10% of the cellulosic materials (average DP = 1000-2000) will degrade in the first stage (up to 10⁵ years) by the peeling-off reaction and will cause an ingrowth of isosaccharinic acid in the interstitial cement pore water. In the second stage (10⁵-10⁶ years), alkaline hydrolysis will control the further degradation of the cellulose. The potential role of microorganisms in the degradation of cellulose under alkaline conditions could not be evaluated. Proper assessment of the effect of cellulose degradation on the mobilization of radionuclides basically requires knowing the concentration of isosaccharinic acid in the pore water. This concentration, however, depends on several factors such as the stability of ISA under alkaline conditions, sorption of ISA on cement, formation of sparingly soluble ISA-salts, etc. A discussion of all the relevant processes involved, however, is far beyond the scope of the presented overview.     

Study of Aging Characteristics of Ternary Blends of Polyethylenes—II

Six film samples of low-density polypropylene (LDPE)/linear LDPE (LLDPE)/high-density polypropylene (HDPE) with varying ratios of LDPE (20–45 ... wt%) and LLDPE (25–50 wt%) having a fixed amount of HDPE at 30 wt% were prepared by blown film extrusion technique. The samples were aged at four different temperatures, 55°, 70°, 85°, and 100°C, for four different time periods in the interval of between 150 hours and up to 600 hours. The change in the structure of various constituents and the formation of various oxygenated (peroxy and hydroperoxy) and unsaturated groups during thermo-oxidative degradation was discussed by infrared spectroscopy. The visiosity-average molecular weight was found to have decreased slowly in the initial aging hours and temperatures, whereas it decreased by 10% with its previous value tensile strength that is, 100°C when aged for 600 hours. The tensile strength of the sample first increased by 67% at 55°C and 89% at 70°C up to 450 hours, whereas the values increased by 52.5% at 85°C and 33.9% at 100°C when aged for 150 hours and then decreased. The percentage elongation at break increased by 2.7% at 55°C and 10.7% at 70°C for 150 and 300 hours of aging, respectively, whereas the percentage decreased when aged at 85°C and 100°C for up to 600 hours of aging. The values of gel content (percent) increased and initial degradation temperature decreased with aging time and temperature.     

Selection of adsorbents for treatment of leachate: batch studies of simultaneous adsorption of heavy metals

The simultaneous adsorption of copper (Cu), cadmium (Cd), nickel (Ni), and lead (Pb) ions from spiked deionized water and spiked leachate onto natural materials (peat A and B), by-product or waste materials (carbon-containing ash, paper pellets, pine bark, and semi-coke), and synthetic materials (based on urea-formaldehyde resins, called blue and red adsorbents) or mixtures thereof was investigated. The adsorbents that gave the highest metal removal efficiencies were peat A, a mixture of peat B and carbon-containing ash, and a mixture of peat A and blue. At an initial concentration of 5 mg/l for each metal, the removal of each species of metal ion from spiked water and spiked leachate solutions was very good (>90%) and good (>75%), respectively. When the initial concentration of each metal in the solutions was twenty times higher (100 mg/l), there was a noticeable decrease in the removal efficiency of Cu²⁺, Cd²⁺, and Ni²⁺, but not of Pb²⁺. Langmuir monolayer adsorption capacities, q_m, on peat A were found to be 0.57, 0.37, and 0.36 mmol/g for Pb²⁺, Cd²⁺, and Ni²⁺, respectively. The order of metal adsorption capacity on peat A was the same in the case of competitive multimetal adsorption conditions as it was for single-element adsorption, namely Pb²⁺ > Cd²⁺ ≥ Ni²⁺. The results show that peat alone (an inexpensive adsorbent) is a good adsorbent for heavy metal ions.     

袋式除尘器气流分布数值计算研究

采用结构化/非结构化混合网格技术、多孔介质模型及k-ε两方程湍流模型,对某袋式除尘器及进出口管道内的气体流场进行了数值计算.计算结果表明,合理布置导流板后,袋式除尘器两箱体流量偏差为1.8％;除尘器下游滤袋单元处理气量偏大,中游滤袋单元处理气量较小,最大流量与最小流量偏差为22.3％;靠近除尘器进口处灰斗内存在气流回流特性,易造成粉尘的二次附着现象.     

Effect of Degree of Substitution of Octenyl Succinate Starch on Enzymatic Degradation

Octenyl succinate starch of degree of substitution (ds) 0.03, 0.07, and 0.11 was synthesized in an aqueous medium. These compounds were then tested for the susceptibility to enzymatic degradation. The multiple-enzyme regime of -amylase, amyloglucosidase, and pullulanase was chosen for the evaluation. This combination of enzymes had been proven to degrade 99.5% of unmodified starch to glucose and hence was chosen for this study. It was found that even small amounts of subsituent caused a considerable decrease in the extent of degradation. The net extent of degradation decreased with increasing ds. Surprisingly, the amount of glucose from all three substituted substrates was quite similar, suggesting the effect small amounts of subtituent had on the enzymatic activity.     

Effects of temperature on the release of nutrient elements of solid organic materials under conditions of oversaturation

The effects of temperature on the release of chemical components of six solid organic materials under conditions of oversaturation were investigated in this paper. The six materials were peat moss (PM), weathered coals (WC), charred rice husks (CRH), sawdust (Sd), turfgrass clippings (TC), and chicken manure (CM). Significant differences were observed in the available nitrogen and phosphorus content of the aqueous extracts of organic materials at different temperatures. The available nitrogen content in aqueous extracts of PM and WC at 25 °C was higher than that registered at 15 °C and 35 °C. Available nitrogen content in the aqueous extracts of CRH, Sd, TC, and WC at 35 °C was higher than at 15 °C and 25 °C. The available phosphorus content in the aqueous extracts of organic materials at 35 °C was higher than that available at 15 °C and 25 °C, with the exception of Sd. In addition, the release of available phosphorus in the aqueous solution of organic materials at different temperatures varied constantly for 108 h. The release of potassium (K⁺) and sodium (Na⁺) ions in the aqueous extracts of organic materials was basically steady over time, with the exception of CM. High temperature (35 °C) may significantly hasten the release of K⁺ from organic substrates (except for WC) with low temperatures significantly inhibiting release of K⁺ in Sd and CRH. High temperatures (35 °C) might significantly facilitate the release of Na⁺ in CM and TC. However, no significant differences were manifested in the release of Na⁺ from organic substrates at different temperatures, with the exception of CM and TC. Moreover, no significant differences were observed in the release of calcium, magnesium and iron ions with time, nor were there any significant differences in the contents of iron ions in the aqueous extracts of organic materials at different temperatures. The results indicate that multiple mediums should be pretreated in water for a week before being used for planting. They should be used when all mineral elements of organic materials are steady and ignoring the effect of organic mediums.     

Kinetics of Hydrolytic Degradation of PLA

The chemical recycling of poly(lactic acid) (PLA) to its monomer is crucial to reduce both the consumption of renewable resources for the monomer synthesis and the environmental impact related to its production and disposal. In particular, the production of lactic acid from PLA wastes, rather than from virgin raw materials, it is also possible to achieve considerable primary energy savings. The focus of this work is to analyse deeply the PLA hydrolytic decomposition by means of a kinetic model based on two reactions mechanism. To this end, new experimental data have been gathered in order to investigate a wider temperature range (from 140 to 180 °C) and to extend the water/PLA ratio up to 50 % of PLA by weight. The reported results clearly highlight that more than 95 % of PLA is hydrolyzed to water-soluble lactic acid within 120 min, when it is hydrolyzed within 160–180 °C. Furthermore, the kinetic constant is highly influenced by reaction temperature. The proposed “two reactions” kinetic mechanism complies satisfactorily with the experimental data under analysis.