MDEA/DEA脱硫脱碳混合溶液在长庆气区的应用

随着长庆气区靖边等气田的不断开发,其天然气气质发生了较大变化,其中H2S含量上升到1000mg/m3,CO2体积分数上升到4.5%～6.0%,原天然气净化工艺采用的单一MDEA溶液已不能满足天然气脱硫脱碳需要。为此,开展了不同体积比MDEA/DEA混合醇胺溶液脱硫脱碳试验。试验结果显示:在相同的试验条件下,溶液中总胺为40%(质量分数),DEA与MDEA体积比为1:6配比制成的混合溶液其H2S和CO2负荷最高,溶液的脱硫脱碳性能最好。继而在4套生产装置进行了推广应用。结论表明:应用MDEA/DEA混合溶液对低含硫、高含碳的天然气进行净化处理,溶液酸气负荷较高,脱硫、脱碳性能较好,腐蚀性小,天然气净化装置运行平稳,节能效果好,经济适用。

CJST塔盘在天然气胺法脱硫脱碳装置上的应用

天然气脱硫脱碳装置的脱硫塔中醇胺混合溶液普遍存在发泡现象,给生产带来一定影响。本文根据发泡现象的机理和危害,分析了缓解发泡现象五个主要途径的效果。经过对比,选取了新研发的CJST塔盘进行室内和现场应用试验。由试验得知,该塔盘可以较好解决胺法脱硫塔内的发泡问题,并有一定的节能降耗作用。

Absorption Rate of CO_2 into MDEA Aqueous Solution Blended with Piperazine and Diethanolanline

Absorption rate of CO2 into aqueous solution of N-methyldiethanolamine (MDEA) blended with diethanolamine (DEA) and piperazine (PZ) was studied and a kinetic model was established. It is shown that homogeneous activation mechanism could explain this absorption process. The absorption rate coefficients of carbon dioxide into MDEA aqueous solution blended with DEA, PZ or DEA+PZ were compared with each other. The results demonstrated that the different activation effect of DEA, PZ and DEA+PZ on the carbon dioxide absorption comes from the difference in CO2 combination rate, transport of PZ and DEA to MDEA and the regeneration rate of PZ and DEA.

电感耦合等离子体质谱法测定土壤中有效态镉

建立电感耦合等离子体质谱(ICP-MS)仪测量土壤样品中有效态镉的方法.为了提高ICP-MS法测量的稳定性和准确度,优化样品粒度、称样量、振荡时间等条件,以二乙三胺五乙酸-三乙醇胺-氯化钙混合溶液(DTPA)为提取剂(固液比为1:12.5),元素铑为内标,ICP-MS仪测定有效态镉的含量.有效态镉的线性范围为0~0.200 mg/L,线性相关系数为0.9998,检出限为0.0009 mg/kg.测定结果的相对标准偏差为1.56%~3.16%(n=6).用该法测定国家标准物质土壤中的有效态镉,测定值与标准值基本一致,相对误差为-2.92%~3.13%.该方法减少了样品的浪费,提高了工作效率,增加了测量稳定性,测定结果准确可靠,在检测大批量土壤有效态镉时更具有优越性.