天然气中汞及其化合物的检测系统与分析方法研究＊

准确测定天然气中汞及其化合物的采样方法和分析技术成为近年来一个重要的研究内容。文章对该项技术进行了实验研究,并依据研发的实验装置建立了相应分析方法。实验表明:甲基汞加标回收率为87.5%～92.2%;乙基汞加标回收率为86.5%～92.0%,采用该套检测系统可以对天然气中汞及其化合物进行有效的分离和定量分析。     

燃气锅炉噪声治理技术

本文以治理工程为实例,介绍了燃气锅炉房噪声治理技术和工程效果.     

Sequestration of maize crop straw C in different soils: role of oxyhydrates in chemical binding and stabilization as recalcitrance

While biophysical controls on the sequestration capacity of soils have been well addressed with physical protection, chemical binding and stabilization processes as well as microbial community changes, the role of chemical binding and stabilization has not yet well characterized for soil organic carbon (SOC) sequestration in rice paddies. In this study, a 6-month laboratory incubation with and without maize straw amendment (MSA) was conducted using topsoil samples from soils with different clay mineralogy and free oxy-hydrate contents collected across Southern China. The increase in SOC under MSA was found coincident with that in Fe- and Al-bound OC (Fe/Al-OC) after incubation for 30 d (R(2)=0.90, P=0.05), and with sodium dithionate-citrate-bicarbonate (DCB) extractable Fe after incubation for 180 d (R(2)=0.99, P<0.01). The increase in SOC under MSA was found higher in soils rich in DCB extractable Fe than those poor in DCB extractable Fe. The greater SOC sequestration in soils rich in DCB extractable Fe was further supported by the higher abundance of (13)C which was a natural signature of MSA. Moreover, a weak positive correlation of the increased SOC under MSA with the increased humin (R(2)=0.87, P=0.06) observed after incubation for 180 d may indicate a chemical stabilization of sequestered SOC as humin in the long run. These results improved our understanding of SOC sequestration in China's rice paddies that involves an initial chemical binding of amended C and a final stabilization as recalcitrant C of humin.     

Effect of long-term fertilization on C mineralization and production of CH4 and CO2 under anaerobic incubation from bulk samples and particle size fractions of a typical paddy soil

Impacts of nutrient management on C mineralization and greenhouse gas (GHGs) emission from soils have been of much concern in global change. Using laboratory incubation, the production of CH₄ and CO₂ were studied from both bulk samples and the particle size fractions (PSF) of topsoil from a paddy under a long-term different fertilization trial (including non (NF), chemical without (CF) and with manure (CFM) fertilization, respectively) in the Tai Lake Region, China. Four PSFs (2000–200, 200–20, 20–2, <2 μm) were separated from undisturbed samples collected after rice harvest by a low-energy ultrasonic dispersion procedure. Both the bulk samples and PSFs were incubated under submerged condition for 72 days. The concentration of CH₄ and CO₂ evolved during incubation were determined by gas chromatography. C mineralization rates ranged from 0.13 to 0.52 mg C g⁻¹ C day⁻¹, with different fertilizations and size of the PSFs, and were not correlated with C/N ratio. While CO₂ production predominated over CH₄ from C mineralization from both bulk samples and the size fractions, CH₄ production played a predominant role in the total global warming potential (GWP) under all treatments. C mineralization of bulk soil was significantly higher under CF than under CFM and NF. CH₄ production, however, was 3 times as under CFM and 27 times as under NF, indicating a tremendous effect of chemical fertilization alone on the total GWP. CO₂ production from the PSFs differed from CH₄ under a single treatment, which was notably from the coarse PSFs larger than 200 μm. Higher C mineralization and CH₄ production with a higher metabolic quotient under CF implicated a vulnerability of soil functioning of GHGs mitigation in the paddy receiving chemical fertilizers only. Thus, rational organic amendments should be undertaken for mitigating the climate change.     

水样品中挥发酚的测量不确定度的评定方法

根据环境监测的要求,中国石油集团安全环保技术研究院实验室在出具数据时要对测量结果进行测量不确定度评定。用实例建立了分光光度法测定水样品中挥发酚的合成标准不确定度的数学模式,它由质量的标准测量不确定度和体积的标准测量不确定度组成;并对这两部分标准不确定度的分量作了详尽的分析和计算。得出测量扩展不确定度结果。     

测定水样中化学需氧量的不确定度

对化学需氧量测定的不确定度进行合理评定,应充分考虑测定过程中的不确定度来源。建立了重铬酸钾法测定水样中化学需氧量不确定度的数学模型,对组成化学需氧量的各个因子的不确定度分量进行了详尽的分析和计算,得出了本次样品CODCr的测定结果为72.2mg/L,扩展不确定度为3.8mg/L。     

环境预警系统的类型和构成

环境预警系统的类型和构成研究可为各级政府和企业提供决策依据。通过调研国内外环境预警系统的类型和构成要素,提出石油企业环境预警系统的设想,并对目前存在的问题进行探讨,以实现对环境事件及时预防的作用。     

煤层气采出水中重金属含量分析

概述了国内外煤层气的开发利用现状,针对煤层气开发过程中采出水的利用价值,结合多个井场采出水的样品实测数据,详细讨论了重金属及其他污染物含量对煤层气采出水利用价值的影响,对其中所含各类污染物质及重金属进行了分类对比分析,提出了煤层气采出水综合利用的处理建议。     

油气回收技术发展现状及其在我国的应用前景

重点介绍了油气回收的必要性及目前国际上通用的几种油气回收技术和方法,并对油气回收技术在我国的应用前景进行了预测。油气回收技术是一个系统工程,在设计和选型时,应该注意油气收集系统和油气回收装置的同等重要性。