Henry’s Law Constant Variations of Volatile Organic Compounds in Wastewater and Activated Sludge

Received: May 31, 2006
Revised: May 31, 2006
Accepted: May 31, 2006
Download Citation: RIS|BibTeX|https://doi.org/10.4209/aaqr.2006.06.0006  

Cite this article:
Lin, J.H. and Chou, M.S. (2006). Henry’s Law Constant Variations of Volatile Organic Compounds in Wastewater and Activated Sludge. Aerosol Air Qual. Res. 6: 180-192. https://doi.org/10.4209/aaqr.2006.06.0006

ABSTRACT

Henry’s law constant is an important equilibrium factor in the mass transfer process of volatile organic compounds (VOCs). A single equilibration technique (SET) was adopted to measure the air-water dimensionless (K_H) and the dimensionless apparent (K'_H) of Henry’s law constant in an air-wastewater system and air-activated sludge for VOCs at 298 K. Hydrophilic VOCs (methanol, isopropanol and acetone) and hydrophobic VOCs (toluene and p-xylene) were used as target compounds. Deionized (DI) water, (DI-water diluted and a pasteurized wastewater (abbreviated as wastewater) with a maximum dissolved total organic carbon (TOC) content of 700 mg/L) and DI-water diluted and pasteurized activated sludge (abbreviated as mixed liquor) with a maximum suspended solid concentration of 40,000 mg/L were used as liquids.

(K'_H) of the target hydrophilic compounds in the mixed liquor with a maximum-suspended solid concentration were 8.9 to 19.9% higher than those in DI water. Those for toluene and p-xylene decreased up to 70.8 and 88.3% in the mixed liquor, respectively. (K'_H) of all the test compounds in the wastewater was only 1 to 11% smaller than those in DI water. A model was proposed for correlating (K'_H) with wastewater TOC and activated sludge concentration using an organic carbon-water partition coefficient (K_OC) and activated sludge-water partition coefficient (K_P) as model parameters.

Keywords: Partition coefficient; phase equilibrium; mixed liquor suspended solid; total organiccarbon; bioscrubbing