Using carbon dioxide gas to lower the pH of tunnelling waste water &ndash; laboratory test and assessment of toxic potential

GSTDTAP > 气候变化

	Using carbon dioxide gas to lower the pH of tunnelling waste water - laboratory test and assessment of toxic potential
	Garmo, Øyvind Aaberg; Escudero, Carlos
	2014
出版年	2014
语种	英语
国家	挪威
出版者	Norsk institutt for vannforskning
领域	气候变化
英文摘要	Building of tunnels produces waste water that often is highly alkaline. Such water can be toxic to aquatic organisms, and pH should be lowered before discharge to recipient. A reactor tank was built to test the use carbon dioxide (CO2) gas for this purpose. Small scale experiments were conducted with three synthetic solutions prepared by diluting acids and bases, and one sample of tunnelling waste water from Gran, National road 4 (rv. 4). The pH decreased rapidly to pH 8.0 when CO2 gas was added to alkaline solutions. The rate of pH decrease was markedly slower below pH 7.0. The CO2 concentration was low (<40 mg/L) at pH values higher than 8.0, but increased rapidly as pH dropped below 8.0. Initially, the pH dropped faster and the CO2 concentrations increased faster at 4 °C than at 15 °C, but there were no clear differences when the experiments were terminated. The aqueous CO2 concentration in tunnelling waste water at pH 8.0 is probably not acutely toxic to fish, but can rapidly rise to toxic levels if pH declines further.
英文关键词	VDP::Matematikk og naturvitenskap: 400 VDP::Mathematics and natural scienses: 400 Karbondioksid / Carbon dioxide PH justering / PH adjustment Samferdsel / Transport and communication Tunneldrivevann / Tunnelling water
URL	查看原文
来源平台	Center for International Climate and Environmental Research-Oslo (CICERO)
文献类型	科技报告
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/2003
专题	气候变化
推荐引用方式 GB/T 7714	Garmo, Øyvind Aaberg,Escudero, Carlos. Using carbon dioxide gas to lower the pH of tunnelling waste water - laboratory test and assessment of toxic potential:Norsk institutt for vannforskning,2014.