Coalbed methane produced water in China: status and environmental issues

As one of the unconventional natural gas family members, coalbed methane (CBM) receives great attention throughout the world. The major associated problem of CBM production is the management of produced water. In the USA, Canada, and Australia, much research has been done on the effects and management of coalbed methane produced water (CMPW). However, in China, the environmental effects of CMPW were overlooked. The quantity and the quality of CMPW both vary enormously between coal basins or stratigraphic units in China. The unit produced water volume of CBM wells in China ranges from 10 to 271,280 L/well/day, and the concentration of total dissolved solids (TDS) ranges from 691 to 93,898 mg/L. Most pH values of CMPW are more than 7.0, showing the alkaline feature, and the Na-HCO₃ and Na-HCO₃-Cl are typical types of CMPW in China. Treatment and utilization of CMPW in China lag far behind the USA and Australia, and CMPW is mainly managed by surface impoundments and evaporation. Currently, the core environmental issues associated with CMPW in China are that the potential environmental problems of CMPW have not been given enough attention, and relevant regulations as well as environmental impact assessment (EIA) guidelines for CMPW are still lacking. Other potential issues in China includes (1) water quality monitoring issues for CMPW with special components in special areas, (2) groundwater level decline issues associated with the dewatering process, and (3) potential environmental issues of groundwater pollution associated with hydraulic fracturing.     

Identification of main influencing factors of life cycle CO2 emissions from the integrated steelworks using sensitivity analysis

The amount of CO₂ emissions from steelworks accounts for a great share of the total CO₂ emissions from industry in China. Thus, reducing CO₂ emissions from steelworks is urgent for China's environmental protection and sustainable development. This study aims at identifying factors that influence CO₂ emissions from steelworks and proposing measures to reduce CO₂ emissions. The life cycle inventory (LCI) of iron and steel products implies the relationship between the CO₂ emissions of the steelworks and the input variables of the LCI. The Tornado Chart Tool is utilized to calculate the variation of CO₂ emissions caused by the change of each input variables of LCI. Then, mean sensitivity of each input variable is calculated and the ranking criterion developed is used to identify the main factors influencing the integrated steelworks. Subsequently, measures for reducing CO₂ emissions are proposed. The results indicate that the very important influencing factors of CO₂ emissions in steelworks are the CO₂ emission factor of Blast Furnace Gas (BFG), liquid steel unit consumption of continuous casting, continuous casting slab unit consumption of hot rolling and hot metal ratio of steel making. Consequently, many efficient measures for reducing CO₂ emissions have been proposed, such as removing CO₂ contained in BFG, decreasing the hot metal ratio of Basic Oxygen Furnace (BOF), recycling BFG, optimizing the products' structure, etc.     

喀斯特水库碳、硅耦合循环:以红枫湖、普定水库和平寨水库为例

通过研究红枫湖、普定水库和平寨水库三个喀斯特水库的碳、硅循环,探讨了水库碳-硅循环的耦合关系。藻类光合作用导致表层水体溶解硅(DSi)及溶解无机碳(DIC)的亏损;当DSi供应不足时,硅藻生长繁殖大量消耗DSi,导致DSi相对DIC快速亏损。沉降颗粒物中内源有机碳含量越高,生物硅(BSi)及有机碳(OC)含量越高,但OC/BSi受控于硅藻对沉积物有机碳贡献率,且与之呈反比。生物硅与有机碳含量之比K值(K=BSi/OC)可作为硅藻贡献率的潜在替代指标,并与之呈正相关;生物硅与内源有机碳(OC_(auto))含量之比K_(auto)值(K_(auto)=BSi/OC_(auto))可作为水体富营养化程度的潜在替代指标,并与富营养化程度呈负相关。     

Future private car stock in China: current growth pattern and effects of car sales restriction

Mitigation and Adaptation Strategies for Global Change - Car stock projection is essential to evaluating the energy and environmental impacts of private cars in China. Since the private car...     

循环经济发展能值评价及实证研究

定量评价循环经济的发展水平是循环经济的一个基础理论课题,本文在辽宁省1996-2005的统计数据基础上,运用能值分析方法,从能值流量、能值经济、投入产出、环境压力和综合指数5个方面评价了辽宁省循环经济发展状况。研究结果表明,从总能值用量和能值密度的变化趋势来看,辽宁省经济发展水平较高,很大程度上依赖于不可更新的能源消耗。能值自给率和能值投资率的变化趋势说明,辽宁省自然资源相对丰富,经济发展的资源基础相对雄厚,经济的安全性较高,但对本地资源的依赖程度高,资源利用效率低,仍是一种高资源消耗型、粗放型的经济发展模式。因此,辽宁省循环经济发展的重点是不可更新资源的合理利用,目标是降低废弃物排放,加强资源的循环利用。     

应对二氧化碳浓度上升问题的研究:CO_2的捕获、储存与利用

为了缓解日益严重的CO2浓度升高导致的温室效应等环境问题,针对各国CO2过量排放与温室效应逐渐加剧的现状,讨论传统CO2减排方法与CO2的捕获、储存与利用(CCSU)的优缺点和优势互补,论述针对大型CO2排放点的减排措施——CCSU的必要性。对CCSU进行系统的介绍和认识,并对CCSU所包含的各种捕获技术、储存技术以及利用技术的特点进行对比和分析,论述其适用范围、地域和经济因素。结合国外一些现有的应用CO2的先进技术和经验,对CO2的捕获与利用的联用作出分析和展望。尤其是CO2的化工利用具有广阔的研发和发展前景,CO2EOR(CO2提高采收率技术)在技术和经济上具有实际应用意义。为新型环保型能源体系的建设提供参考。     

味精-卡那霉素混合废水的厌氧生物处理

采用改进结构的上流式厌氧污泥床反应器,在３５℃下处理味精,卡那霉素混合废水。试验结果表明：预先排除大部分气体,可有效地控制污泥上浮,使厌氧消化集中在床部完全;     

LIGNIN SEPARATION BY CONTINUOUS ION FLOTATION: INVESTIGATION OF PHYSICAL OPERATIONAL PARAMETERS1

ABSTRACT: Ion flotation is the term used to describe a process in which there is an initally homogeneous solution which becomes heterogeneous after the addition of an oppositely charged surfactant due to the reaction between the surfactant and specific ion(s); thus, insoluble complexes are formed. These insoluble complexes will then attached to the bubbles passing through the solution and thus leave in the foam phase. The performance of the continuous ion flotation process for the removal of haft lignin from water was investigated intensively using liquid flow rates, gas flow rates, feed locations and solution height as operational variables. The interrelationships among these physical parameters were studied and discussed. A dimensionless operational chart was established for process control. Results demonstrate that ion flotation is an effective process for removing lignin from water, provided that a quaternary ammonium salt, such as cetyldimethylbenzyl-ammonium chloride or the like, is used as a collector. At optimum operational conditions, higher than 0.95 fractional removal of lignin can be achieved.     

我国石油消费现状及其战略思考

石油是支撑经济发展和国防现代化的基本能源之一。在当今国际社会中 ,石油已成为世界政治、经济、军事和外交斗争的特殊武器 ,成为一国经济发展、社会稳定以及国家安全的重要保障条件。我国目前石油供需形势严峻 ,主要表现为 :石油储量接替准备不足 ,老油田稳产面临严峻形势 ;需求增长过快 ;对外依存度较高 ;运输和贮存能力较小等方面。石油的安全及其保障问题关系到我国的经济安全和国家安全 ,因此 ,有必要研究我国的石油消费现状及发展战略。笔者针对我国的石油消费现状 ,分析了目前我国石油战略中存在的问题 ,探讨了我国的石油战略。     

AGRICULTURE LAND‐USE EFFECTS ON NUTRIENT LOSSES IN WEST TIAOXI WATERSHED,CHINA1

ABSTRACT: Five types of land use/land covers in the West Tiaoxi watershed of China were studied for nutrient losses in artificial rainstorm runoff. A self‐designed rainfall simulator was used. In situ rainfall simulations were used to: (1) compare the concentrations of nitrogen and phosphorous in different land use/land covers and (2) evaluate the flux of nitrogen and phosphorous export from runoff and sediment in various types of land use/land covers. Three duplicated experiments were carried out under rain intensity of 2 mm/min, each lasting 32 minutes on a 3 m² plot. Characteristics of various species of nitrogen and phosphorous in runoff and sediment were investigated. The results showed that the concentrations of total nitrogen (TN) and total phosphorous (TP) were greatest in runoff from mulberry trees and smallest from pine forest. The TN and TP export was mainly from suspended particulate in runoff. TN and TP exports from the top 10 cm layer of five types of land use/land covers were estimated as high as 4.66 to 9.40 g/m² and 2.57 to 4.89 g/m², respectively, of which exports through sediment of runoff accounted for more than 90 percent and 97 percent. The rate of TN and TP exports ranged from 2.68 to approximately 14.48 and 0.45 to approximately 4.11 mg/m²/min in runoff; these rates were much lower than those of 100.01 to approximately 172.67 and 72.82 to approximately 135.96 mg/m²/min in the runoff sediment.