本文選題：液體�；�　切入點：揮發(fā)　出處：《天津科技大學》2013年碩士論文　論文類型：學位論文

【摘要】：液體危險化學品,簡稱液體�；�,是易揮發(fā)、蒸氣劇毒或有強腐蝕性或有強刺激性的液體,在運輸、生產(chǎn)、儲存、使用過程中經(jīng)常發(fā)生泄漏事故,泄露同時伴生大量有毒氣體。目前,針對液體�；沸孤┦鹿�,如何在第一時間內(nèi)有效控制有毒氣體的生成與傳輸,是應急救援措施亟待解決的關鍵技術難題。然而,目前國內(nèi)外有關液體�；酚卸練怏w生成與傳輸?shù)臋C理研究鮮少報道。本文通過研究鹽酸等四種液體危化品在不同溫度下的自然揮發(fā)過程,計算液體�；返膫髻|(zhì)系數(shù)及傳質(zhì)速率,運用Gaussian03計算液體�；窊]發(fā)過程中團簇結構的變化,從能量障礙角度系統(tǒng)研究有毒氣體生成與傳輸?shù)臋C理。本文以常見的4種液體�；罚喊彼�、鹽酸、甲醛、硝酸為研究對象。以溫度為液體�；窊]發(fā)的主要影響因素,在20℃～45℃進行了400min自然揮發(fā)實驗,通過測定溶液濃度隨時間的變化規(guī)律、計算傳質(zhì)系數(shù)及傳質(zhì)速率,研究4種液體�；返膿]發(fā)過程。實驗結果表明,液體�；返膿]發(fā)隨著溫度的增加而加強,但揮發(fā)速率在溫度方面都存在明顯的區(qū)域性,即在相應的區(qū)域內(nèi)揮發(fā)程度相似。并且,4種液體�；分�,氨水的揮發(fā)速度最快,鹽酸與甲醛的揮發(fā)次之,硝酸的揮發(fā)最難進行,35℃時氨水的傳質(zhì)系數(shù)為1.97×10-4 m/min;鹽酸為0.934×10-5 m/min;甲醛為0.880×10-5 m/min;硝酸為0.803 ×10-6m/min。本文通過團簇結構的能量計算出團簇結構變化過程中所需的能量。得出結論：氨水揮發(fā)過程中各階段所需要的能量分別為11.09kJ/mol、13.76kJ/mol、18.67kJ/mol,氨水揮發(fā)為逐漸變慢的過程；鹽酸揮發(fā)過程中各階段所需要的能量分別為21.81kJ/mol、51.39kJ/mol、18.42kJ/mol,鹽酸的揮發(fā)過程為逐漸變慢然后變快的過程；甲醛揮發(fā)過程中各階段所需要的能量分別為22.55kJ/mol、18.98kJ/mol,甲醛的揮發(fā)過程為逐漸變快的過程；硝酸揮發(fā)過程中各階段所需要的能量分別為63.17kJ·mol-1、 107.9kJ·mol-1,硝酸的揮發(fā)過程為逐漸變慢的過程。
[Abstract]:Liquid hazardous chemicals, referred to as liquid hazardous chemicals, are volatile, highly toxic, or highly corrosive or irritating liquids, often leaking in the course of transportation, production, storage and use. At present, how to effectively control the generation and transmission of toxic gases in the first time is a key technical problem to be solved in emergency rescue measures. There are few reports at home and abroad on the mechanism of formation and transport of toxic gases of liquid dangerous chemicals. In this paper, the natural volatilization processes of four kinds of liquid dangerous chemicals such as hydrochloric acid at different temperatures are studied. The mass transfer coefficient and mass transfer rate of liquid dangerous chemicals were calculated, and the change of cluster structure during the volatilization of liquid dangerous chemicals was calculated by Gaussian03. The mechanism of the formation and transport of toxic gases is systematically studied from the point of view of energy barrier. In this paper, four kinds of liquid dangerous chemicals: ammonia, hydrochloric acid, formaldehyde, nitric acid are taken as the research objects, and temperature is taken as the main influencing factor of volatilization of liquid dangerous chemicals. A 400min natural volatilization experiment was carried out at 20 鈩，

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