Quantification of methane emissions from full-scale open windrow composting of biowaste using an inverse dispersion technique

An inverse dispersion technique in conjunction with Open-Path Tunable-Diode-Laser-Spectroscopy (OP-TDLS) and meteorological measurements was applied to characterise methane (CH₄) emissions from an Austrian open-windrow composting plant treating source-separated biowaste. Within the measurement campaigns from July to September 2012 different operating conditions (e.g. before, during and after turning and/or sieving events) were considered to reflect the plant-specific process efficiency. In addition, the tracer technique using acetylene (C₂H₂) was applied during the measurement campaigns as a comparison to the dispersion model. Plant-specific methane emissions varied between 1.7 and 14.3 g CH₄/m³d (1.3–10.7 kg CH₄/h) under real-life management assuming a rotting volume of 18,000 m³. In addition, emission measurements indicated that the turning frequency of the open windrows appears to be a crucial factor controlling CH₄ emissions when composting biowaste. The lowest CH₄ emission was measured at a passive state of the windrows without any turning event (“standstill” and “sieving of matured compost”). Not surprisingly, higher CH₄ emissions occurred during turning events, which can be mainly attributed to the instant release of trapped CH₄. Besides the operation mode, the meteorological conditions (e.g. wind speed, atmospheric stability) may be further factors that likely affect the release of CH₄ emissions at an open windrow system. However, the maximum daily CH₄ emissions of 1 m³ rotting material of the composting plant are only 0.7–6.5% of the potential daily methane emissions released from 1 m³ of mechanically–biologically treated (MBT) waste being landfilled according to the required limit values given in the Austrian landfill ordinance.     

国外用遥感研究灾害的现状及其发展

本文着重介绍了美、苏、加、日等国在使用遥感技术对地震、滑坡、泥石流、火山、洪水等灾害进行观测研究的状况及其发展动态,可供借鉴。     

原子吸收光谱仪的背景校正

介绍了原子吸收光谱仪的５种主要的背景校正技术（邻近谱线技术，连续光源法，塞曼法，自吸法及连续光源单色器波长调节法ＣＥＷＭ）及其主要产品，分析评述了各种校正技术的原理，特点及其应用状况。     

城市生态环境质量分区方法学研究

城市生态环境质量是影响城市景观和居民身心健康的最重要的因素之一，环境质量分区是进行城市生态环境评价的基础性工作，是进行城市环境规划的重要依据之一。本文从环境质量分区的概念阐述入手，在分析传统分区方法的同时，提出城市环境质量分区的遥感技术法，证明遥感技术应用于城市环境质量分区，具有精度高，快速和省力的特点。     

林火管理经济学的研究与探讨——多种防火要素投入的最佳组合

用经济学的观点分析了多种防火要素投入时的等减灾效益与等成本曲线,研究了多种防火要素之间的相互替代与边际替代率问题,提出了多种防火要素投入时最佳组合的判据。     

一种优化的地铁站消声器

空调系统中大功率风机产生的噪声是地铁站主要的噪声污染源。对地铁站工作人员和乘客及地铁站周围居民的生活环境影响非常严重 ,在此介绍一种优化的地铁站消声器 ,比传统消声器易于安装 ,消声效果好 ,成本低 ,在广州地铁站环控系统应用中一次达标 ,效果良好。     

染料废水脱色方法

染料污水中污染物主要来自一些成色物质，如活性黄、活性蓝、碱性紫、碱性蓝等，染料的可生化性一般都较差，并使污水呈现出一定的色度，影响了美观。本文就染料废水最新的一些脱色方法进行了探讨。     

固定化细胞技术在废水处理中的应用

固定化（主要为固定化微生物）技术，由于降解效率高，抗逆性强等优点，在废水处理中应用广泛。按作用方式不同，固定化技术可分为4类，其中吸附法与包埋法应用较多。为提高机械强度与处理效率，包埋剂常与交联剂和吸附剂联用。结合90年代以来，固定化方法的研究成果和应用实例对化技术作了较全面的论述。     

海藻酸钠包埋活性炭与活性污泥的固定化技术

以海藻酸钠为包埋剂，以粉末活性炭和硅藻土分别为吸附剂，探索了用蠕动泵滴动法制备固定化活性污泥球形颗粒的工艺过程，并对所制备的固定化活性污泥球形颗粒，进行了餐厅废水的处理静态实验，从中检验了固定化颗粒的性能。实验结果表明，以活性炭为吸附剂添加制得的固定化活性污泥球形颗粒，具有较好的处理能力，是一种合适的材料，而以硅藻作为吸附剂添加时则效果较差。     

In situ IR,pulse reaction and TPD-ITD study of catalytic performance of room-temperature carbon monoxide oxidation on supported gold catalysts

With in situ IR, two different CO adsorption bands were detected on various chemical state gold catalysts. One band is attributed to the linear CO on an oxidized gold catalyst(2100 cm i ), the other one is ascribed to the bridged CO on metallic gold (2085 cm- i ). CO pulse reaction showed that Au/Fe203 catalyst had a room-temperature activity even in the presence of moisture. The produced CO2 was detained and more easily desorbed from supported gold catalyst than support oxide. TPD-IDT results indicated that the 02- superoxide ions are the possible active oxygen species.