title: Reducing THMFP by H2O2/UV oxidation for humic acid of small molecular weight.
abstract: In this study, the merits of using H2O2/UV oxidation for reducing trihalomethane formation potential (THMFP), colour, and dissolved organic carbon (DOC) of smaller molecular humic acid were investigated, especially the energy consumption based on EEO. The results show that THMFP decreases by increasing oxidation time, H2O2 dose and UV intensity. The reaction constant in descending order is kColour>kDOC>kTHMFP. Furthermore, EEO shows three trends. First, it decreases as H2O2 dose increases. That is, by increasing the amount of H2O2 dose, the electrical energy efficiency becomes better. Second, EEO,9 W>EEO,13 W, implying that higher UV power would result in a higher electrical energy efficiency. Third, EEO,THMFP>EEO,DOC>EEO,colour. That is, the electric energy efficiency is the best for colour removal, second for DOC removal, and third for THMFP reduction. The operation costs for 90% removal of colour, DOC, and THMFP are from 0.31 to 0.69, from 0.78 to 1.72, and from 1.11 to 2.29 US$/m3, respectively. However, reducing THMs to Taiwan's drinking water standard of 80 µg/L needs only 0.25-0.60 US$/m3. Therefore, the condition with UV of 9 W, H2O2 of 50 mg/L, and oxidation time of 23 min can be applied for THMs reduction as the cost is the smallest of 0.25 US$/m3, even lower than current Taiwan's drinking water price of 0.3 US$/m3.
authors.affiliation: a Chemical and Biochemical Engineering Department , Kao Yuan University , Lujhu District, Kaohsiung City 82151 , Taiwan, Republic of China.
authors.forename: Hsing Yuan
authors.initials: HY
authors.lastname: Yen
authors.forename: Li Shuang
authors.initials: LS
authors.lastname: Yen
mesh_terms: D060766:Drinking Water / Q000737:chemistry; D004560:Electricity; D006812:Humic Substances / Q000032:analysis / Q000191:economics*; D006861:Hydrogen Peroxide / Q000737:chemistry* / Q000191:economics; D008970:Molecular Weight; D010084:Oxidation-Reduction / Q000187:drug effects / Q000528:radiation effects; D011829:Radiation Dosage; D013624:Taiwan; D022882:Trihalomethanes / Q000191:economics / Q000302:isolation & purification*; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification* / Q000528:radiation effects; D018508:Water Purification / Q000191:economics* / Q000379:methods*
chemical_list: D060766:Drinking Water; D006812:Humic Substances; D022882:Trihalomethanes; D014874:Water Pollutants, Chemical; D006861:Hydrogen Peroxide
keywords: H2O2/UV; THMFP; electrical energy per order; humic acid; reaction constant