Techno-economic analysis of natural gas combined cycles with post-combustion CO2 absorption, including a detailed evaluation of the development potential

We performed a detailed analysis of the potential future costs and performance of post-combustion CO₂ absorption in combination with a natural gas combined cycle (NGCC). After researching state-of-the-art technology, an Excel model was created to analyze possible developments in the performance of energy conversion, CO₂ capture, and CO₂ compression. The input variables for the three time frames we used were based on literature data, product information, expert opinions, and our own analysis. Using a natural gas price of 4.7 €/GJ, we calculated a potential decrease in the costs of electricity from 5.6 €ct/kWh in the short term to 4.8 €ct/kWh in the medium term and 4.5 €ct/kWh in the long term. The efficiency penalty is calculated to decline from 7.9%-points LHV in the short term to 4.9%-points and 3.7%-points in the medium and long terms, respectively. In combination with NGCC improvements, this may cause an improvement in the net efficiency, including CO₂ capture, from 49% in the short term to 55% and 58% in the medium and long terms, respectively. The total capital costs including capital costs of the NGCC ware calculated to decline from 880 in the short term to 750 and 690 €/kW in the medium and long terms, respectively, with a decline in the incremental capital costs due to capture from 350 in the short term to 270 and 240 €/kW in the medium and long terms, respectively. Finally, the avoidance costs may decline from 45 €/tCO₂ in the short term to 33 €/tCO₂ in the medium term and 28 €/tCO₂ in the long term.     

可再生能源技术在我国旅游循环经济发展中的应用

可再生资源代替常规能源使用，是旅游可持续发展的客观要求，是旅游循环经济应用的重要方面。太阳能、风能、水能、生物质能、地热能和海洋能利用技术可广泛应用于旅游循环经济系统中的旅游区（点）、旅行社、住宿、餐饮、交通、购物、娱乐等旅游企业。应采取观念更新、政府支持、技术支持等措施推进可再生资源技术在发展旅游循环经济中的研发、推广与运用。     

管理循环用于安全和环境管理工作的探索

根据国际标准化组织颁布的两个系列标准的特点,分析了如何运用管理循环于安全管理和环境管理实践中,提出了制约因素管理循环,并且阐述了管理职能循环、PDCA循环和制约因素管理循环运用于管理工作实践中三者的关系.     

产品导向的环境政策研究进展

产品在整个生命周期都可能对环境造成不同程度的不利影响,因此传统的"末端处理"或"中端处理"的环境产品政策已经不能满足环境需要,产品导向的环境产品政策正是基于这种考虑产生的。通过介绍欧盟几个国家的产品导向的环境产品政策,论述了产品导向的环境产品政策的基本理论及研究进展。     

Risk Analysis of Volatile Organic Compounds Through Daily Life Cycle in the Industrial City in Korea

This study analyzed the risk of exposure to volatile organic compounds (VOCs) through a study of activity patterns in the Korean industrial city, Ulsan. The daily life cycle patterns(LCPs) of 331 people in Ulsan were surveyed and the average LCPs in Ulsan were obtained by statistical analysis. Nine to twelve personal air samples of VOC exposure at the breathing zones were collected at each LCP. This included hours for sleeping,cooking and eating, going to and from work, working, participating in field or outdoor activities, reading, watchingTV, and shopping. The components and concentrations of the collected VOCs were identified by a Gas Chromatography-MassDetector (GC-MS). The overall reproducibility of all GC analytical procedures of the simultaneously collected duplicatesample pairs represented a mean of percent differences rangingfrom about 9 to 13%. For the general population of Ulsan, thecarcinogenic and non-carcinogenic risk of exposure to theVOCs during the LCPs was evaluated. The carcinogenic riskwas analyzed using both the chronic daily exposure orlifetime average daily exposure (CDI) and the cancerpotency factor. The non-carcinogenic risk was analyzedusing both the CDI and the chronic reference dose.The major chemical forms of the identified VOCs were oxidized forms (43%), aliphatic alkanes (29%) and aromatics (15%). Even though the highest total exposure strength per unit time of each activity was observed during shopping, the highest totalamount of exposure to VOCs was identified as the exposure duringwork. The total carcinogenic risk of exposure to the carcinogenicVOCs through daily life cycle in Ulsan was 2.0 × 10^-4which is substantially exceeding the permissible carcinogenicrisk level, 10^-5 10^-6. The carcinogenic riskduring most of the life cycle activities, except forreading, mainly performed indoors, was higher than that ofthe activities performed outdoors. The carcinogenic risk bybenzene exposure was about 56% (time weighted average) ofthe total carcinogenic risk by the exposure to thecarcinogenic VOCs. During cooking and eating, shopping andout door activities, however, the carcinogenic risk by theexposure to chlorinated compounds like chloroform exceededthe exposure to benzene. The overall hazard index (non-carcinogenic risk) by a chronic exposure to carcinogenicand non-carcinogenic VOCs through daily life cycle in Ulsanwas evaluated as 3.91 × 10^-1, which is much less than1.0 considered as a hazard level to human health, and thusit seems likely not to produce a severe health hazard.     

括苍山地区中生代火山旋回划分

本文通过对区内中生代火山活动具有代表性的一系列火山机构的剖析,在厘定火山地层层序的基础上,根据统一的旋回划分原则,划分出黄坦、山头郑、上张、塘上等四个火山旋回,分析了各火山旋回与区域构造运动的关系,并与前人划分的旋回作了对比。     

Performance analysis of different orc power plant configurations using solar and geothermal heat sources

ABSTRACT

Energy optimization is performed on hybrid solar-geothermal power plant working according to Organic Rankine Cycle and installed in southern Tunisia. The performances of four different configurations of the power plant are studied. Mass and energy balances are established for the different compounds. The effects of the main operating parameters such as the geothermal water temperature, ambient temperature and direct normal irradiation on the power plant performances are analyzed. A code is established using Engineering Equation Solver software (EES) to perform the required calculations. Obtained results show that the hybrid solar-geothermal power plant with a heat recovery system is the most suitable configuration design giving a better overall energy efficiency of 15.77 and13.11% and a maximum net power of 1089 and 1882 kW in winter and summer, respectively. However, in the summer season, using a heat recovery system can valuable only when the water temperature is higher than 66°C. For air-cooled condenser, the suitable condensing pressure is 1 bar in winter and 1.9 bars in summer.     

LPCVD法制备TiO_2纳米薄膜的生命周期评价

针对纳米材料生产的高能耗、低生产率的特点,用生命周期评价(LCA)方法对纳米TiO_2薄膜生产过程进行了环境影响评价,并通过设置不同的低压化学气相沉积过程(LPCVD)工艺参数,研究了工艺参数中温度和压强对于TiO_2薄膜评价结果的影响。研究显示,纳米TiO_2薄膜生产阶段的环境表现受LPCVD过程工艺参数影响,评价结果可用于指导LPCVD工艺优化。     

季节性河流对下穿地铁隧道结构影响研究

为研究季节性河流的周期丰水与枯水作用对下穿该河床的地铁隧道结构的影响,以某区间隧道下穿浑河河床为工程背景,研究并预测了2012年4月到2022年4月的丰水与枯水周期变化过程中,水体重力作用对隧道管片应力应变的累积影响。利用基于三维显式有限差分法的计算工具Flac-3D,对上述周期变化过程进行了建模,并对隧道结构受到的应力应变影响进行了模拟。结果表明,隧道的长期沉降停止于2014年4月,隧道竖直方向受力稳定于2013年4月。稳定后,隧道沉降量对周期性丰枯作用的响应程度与监测点到河床中心位置的距离成正比,分别为0、1.3%、1.8%;周期性丰枯作用对所有监测点附近区域的竖直受力影响都很大,约为21.7%。     

煤炭生产的水足迹评价研究

水足迹是水资源占用的综合评价指标,能够量化人类活动对水资源和水环境的影响,为水资源的高效利用与可持续管理提供科学参考.本文在WFN水足迹评价方法和国际标准水足迹评价方法的基础上,提出了基于生命周期的包含蓝水足迹、灰水足迹和间接水足迹的能源系统水足迹评价模型.将此模型应用到煤炭生产,计算了我国单位煤炭生产的水足迹.研究结果表明,我国1 GJ煤炭生产的水足迹为0.19 m~3,水足迹的80%来源于采掘过程,从水足迹类型来看,灰水足迹占到了87%的比例.本研究为能源系统水足迹评价提供了方法理论,并可为以煤炭为原料或燃料的下游产品水足迹评价提供数据支撑.