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1.
天津临港工业区作为滨海新区重要组成部分,港口经济特点突出,是我国临港型工业发展的典型代表。从港口工业一体化港区联动的循环经济产业体系、围海造陆特色区域的循环经济发展新模式、公用工程岛资源能源集成共享网路和循环经济支撑体系多维角度,构建临港型工业区循环经济发展思路,探索临港型区域发展循环经济的途径和模式,以期为我国同类区域循环经济发展提供经验借鉴。  相似文献   

2.
根据循环经济理论,针对新疆循环经济的发展,从资源可承载能力、环境发展、社会经济发展三个方面考虑建立新疆循环经济发展的综合评价指标体系,运用熵值法对新疆10年循环经济的发展水平进行综合评价,进而提出了相应的措施,包括完善法律法规体系、加快产业结构调整、加大政策鼓励力度、促进产业集聚等.  相似文献   

3.
在分析山西循环经济发展的基础上,提出山西发展循环经济的典型模式:企业延长产业链模式、产业循环经济园区模式和再生资源回收利用模式,以及在全社会建立资源循环利用体系。  相似文献   

4.
环境污染成为我国可持续发展当中面对的最大问题,发展循环经济是必然选择,然而资金问题制约了循环经济的深入发展。从政府和市场两个角度分析了循环经济发展中融资约束的原因,针对性地提出政府和市场各尽其责、完善支持循环经济发展的融资体系的想法,并以最新的环保项目融资为切入点,为政府与市场的融资合作创新提供了一些思路,最后建议通过实现循环经济融资主体多元化、方式多样化和结构合理化的“三化”来实现循环经济融资的最大、最优化。  相似文献   

5.
从经济发展背景与循环经济内涵入手,提出发展循环经济是多元资源型县域的现实选择。以辽宁省灯塔市为例,构建以循环型工业、循环型农业、循环型社会体系为主体的循环经济体系框架,并指出建立工业生态链、引入静脉产业和实现土地资源的有效循环利用是完善循环经济体系的必要内容。  相似文献   

6.
由传统经济向循环经济转变,既是国情的需要,也是维护国家经济安全的需要.再生资源的回收利用是循环经济发展过程中一个必不可少的环节,从某种意义上说,没有再生资源回收体系的建立,就没有循环经济体系的发展.因此,如何认识理解再生资源回收体系建设,如何促进再生资源行业的发展,对于发展循环经济具有特殊意义.  相似文献   

7.
国有重点大型企业发展循环经济不仅符合国家节能降耗增效的要求,而且符合企业自身生存发展的需要。国有重点大型企业涵盖循环经济发展的重点领域和重点环节,应在循环经济发展中发挥先锋作用。凭借自身的技术和人才优势,为循环经济发展提供技术支撑;同时,引导带动中小企业,建立循环经济产业链,共同推动我国循环经济的发展。  相似文献   

8.
以编制区域循环经济发展规划为主线,概述了我国循环经济发展的总体趋势和资源型城市经济转型试点的接续产业发展规划;探索性地提出制定循环经济产业基地集聚区建设规划的工作思路;强调发挥政府规划和投融资政策的引导作用,以及建立产业政策体系和激励机制的必要性。  相似文献   

9.
在分析我国原镁工业整体形势的基础上,就我国皮江法炼镁的技术现状与国外先进硅热法炼镁技术进行了比较,指出我国原镁工业发展循环经济的潜力所在。根据我国主要镁产区资源及其相关产业特点,提出对皮江法炼镁工艺进行改造和革新,以原镁企业为核心,联合上下游企业,构筑生态工业园以及建立促进原镁工业循环经济发展的配套政策体系为对策,构建我国原镁工业发展循环经济的基本思路,以促进其节能减排,实现可持续发展。  相似文献   

10.
<正>近日,浙江永康市率先推出完整的县域循环经济资源产出率统计核算体系。这是我国首个县级资源产出率核算体系,对推动建立国家和省级层面的资源产出率统计核算和考核评价体系具有重要意义。循环经济作为一种创新性经济增长方式,是保障中国可持续发展基础上最终实现现代化的必由之路。毋庸置疑,发展循环经济是一项社会系统工程,需要着力把握好两个导向。一是正确的舆论导向。发展循环  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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。  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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, qm, 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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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