The presence of aliphatic and aromatic amines in reservoir and canal water as precursors to disinfection by-products
Warangkana Na Phatthalung, Charongpun Musikavong, Oramas Suttinun
Journal of Environmental Science and Health Part A · 2016
This research aimed at determining the dimethylamine (DMA), diethylamine (DEA), dibutylamine (DBA), and aromatic aniline (AN) in reservoir and canal water in the U-Tapao River Basin, Songkhla, Thailand. The trihalomethane formation potential (THMFP) and N-nitrosodimethylamine formation potential (NDMA-FP) of the reservoir and canal water were analyzed. Water samples from two reservoirs and raw water from water treatment plants at upstream, midstream, and downstream locations of the canal were collected twice. The analysis of the DMA, DEA, DBA, and AN were conducted using gas chromatography and spectrofluorometry techniques. The DMA, DEA, and DBA levels in the reservoir and canal waters ranged from not detectable (ND) to 10 µg/L and from ND to 21.2 µg/L, respectively. AN was detected from 123 to 129 ng/L and from 112 to 177 ng/L in the reservoir and canal waters, respectively. The DMA, DEA, DBA, and AN exhibited two fluorescent peaks at 230nmEx/345nmEm and 280 nmEx/355nmEm. These two peaks corresponded to the peak positions of tryptophan. Detection limits of DMA, DEA, and DBA for fluorescent analysis were 500 μg/L whereas that of AN and tryptophan were 10 and 0.5 μg/L, respectively. The NDMA-FP measured in all the water samples was lower than the detection limit of 237 ng/L. THMFP ranged from 175 to 248 μg/L and 214 to 429 μg/L was detected in the reservoir and canal waters, respectively. The THMFP/dissolved organic carbon (DOC) of the reservoir and canal waters were comparable within the ranges of 73 to 131 µg THMFP/mg DOC.
Formation of trihalomethanes of dissolved organic matter fractions in reservoir and canal waters
Charongpun Musikavong, Kanjanee Srimuang, Thunwadee Tachapattaworakul Suksaroj, Chaisri Suksaroj
Journal of Environmental Science and Health Part A · 2016
The formation of trihalomethanes (THMs) of hydrophobic organic fraction (HPO), transphilic organic fraction (TPI), and hydrophilic organic fraction (HPI) of reservoir and canal waters from the U-Tapao River Basin, Songkhla, Thailand was investigated. Water samples were collected three times from two reservoirs, upstream, midstream, and downstream of the U-Tapao canal. The HPO was the major dissolved organic matter (DOM) fraction in reservoir and canal waters. On average, the HPO accounted for 53 and 45% of the DOM in reservoir and canal waters, respectively. The TPI of 19 and 23% in reservoir and canal waters were determined, respectively. The HPI of 29% of the reservoir water and HPI of 32% of the canal water were detected. For the reservoir water, the highest trihalomethane formation potential (THMFP)/dissolved organic carbon (DOC) was determined for the HPI, followed by the TPI and HPO, respectively. The average values of the THMFP/DOC of the HPI, TPI, and HPO of the reservoir water were 78, 52, and 49 µg THMs/mg C, respectively. The highest THMFP/DOC of the canal water was detected for the HPI, followed by HPO and TPI, respectively. Average values of the THMFP/DOC of HPI of water at upstream and midstream locations of 58 µg THMs/mg C and downstream location of 113 µg THMs/mg C were determined. Average values of THMFP/DOC of HPO of water at upstream and midstream and downstream locations were 48 and 93 µg THMs/mg C, respectively. For the lowest THMFP/DOC fraction, the average values of THMFP/DOC of TPI of water at upstream and midstream and downstream locations were 35 and 73 µg THMs/mg C, respectively.
Evolution of Pretreatment Methods for Nanofiltration Membrane Used for Dissolved Organic Matter Removal in Raw Water Supply
Sirikul Siriraksophon, Charongpun Musikavong, Chaisri Suksaroj, Thunwadee Tachapattaworakul Suksaroj
DOAJ (DOAJ: Directory of Open Access Journals) · 2016
Coagulation and microfiltration using polyaluminium chloride (PACl) were investigated as a pretreatment process by nanofiltration to reduce dissolved organic matter in both raw water and treated water at water treatment plants. The dissolved organic matter in the raw water supply may be a precursor of carcinogens produced during the disinfection process. Raw water from pumping stations and treated water from Hat Yai Provincial Waterworks Authority, Songkhla Province, Thailand were used as samples for this study. Fractionation of raw water samples by DAX-8 and XAD-4 resin revealed that they contained hydrophilic, transphilic and hydrophobic groups with hydrophilic the major organic component. PACl coagulation resulted in a higher dissolved organic matter removal than microfiltration techniques. A hybrid coagulation-nanofiltration process was studied. This effectively reduced dissolved organic matter as dissolved organic carbon and UV-254 by 86% and 94% respectively. The hybrid coagulation-nanofiltration process reduced dissolved organic carbons of the hydrophobic group more effectively than the hydrophilic group. Chloroform and bromodichloroform were the two major species of the trihalomethane group produced when raw water reacted with chlorine. The hybrid coagulation-nanofiltration process reduced the trihalomethane formation potential (THMFP) in raw water samples by up to 90%
Alternative Technologies for the Reduction of Greenhouse Gas Emissions from Palm Oil Mills in Thailand
Roihatai Kaewmai, Aran H‐Kittikun, Chaisri Suksaroj, Charongpun Musikavong
Environmental Science & Technology · 2013
Alternative methodologies for the reduction of greenhouse gas (GHG) emissions from crude palm oil (CPO) production by a wet extraction mill in Thailand were developed. The production of 1 t of CPO from mills with biogas capture (four mills) and without biogas capture (two mills) in 2010 produced GHG emissions of 935 kg carbon dioxide equivalent (CO2eq), on average. Wastewater treatment plants with and without biogas capture produced GHG emissions of 64 and 47% of total GHG emission, respectively. The rest of the emissions mostly originated from the acquisition of fresh fruit bunches. The establishment of a biogas recovery system must be the first step in the reduction of GHG emissions. It could reduce GHG emissions by 373 kgCO2eq/t of CPO. The main source of GHG emission of 163 kgCO2eq/t of CPO from the mills with biogas capture was the open pond used for cooling of wastewater before it enters the biogas recovery system. The reduction of GHG emissions could be accomplished by (i) using a wastewater-dispersed unit for cooling, (ii) using a covered pond, (iii) enhancing the performance of the biogas recovery system, and (iv) changing the stabilization pond to an aerated lagoon. By using options i-iv, reductions of GHG emissions of 216, 208, 92.2, and 87.6 kgCO2eq/t of CPO, respectively, can be achieved.