Utilization of pulp and paper industrial wastes to remove heavy metals from metal finishing wastewater

Sthiannopkao, Suthipong,Sreesai, Siranee Elsevier 2009 Journal of environmental management Vol.90 No.11

<P><B>Abstract</B></P><P>Two pulp and paper industrial wastes, lime mud (LM) and recovery boiler ash (RB), have low moisture contents, low heavy metal contaminations and contain various carbonate compounds which contribute to a high pH. Metal finishing wastewater (MF-WW) has a low pH, high levels of TDS and high contaminations from Cr, Cu, Pb and Zn. The heavy metals from MF-WW were removed by sorption and precipitation mechanisms. LM gave better results in removing heavy metals from MF-WW than RB. At a reaction time of 45min, the maximum removal efficiencies for Cr (93%) and Cu (99%) were obtained at 110gL<SUP>−1</SUP> of LM, but at 80gL<SUP>−1</SUP> for Pb (96%) and Zn (99%). Treatment with LM gives a higher sludge volume than with RB. However, the leachability of heavy metals from LM is lower. Leachability of heavy metals in the sediment for all selected treatment conditions is within government standards.</P>

Synthesis and characterization of Fe-MCM-41 from rice husk silica by hydrothermal technique for arsenate adsorption

Wantala, Kitirote,Sthiannopkao, Suthipong,Srinameb, Bang-orn,Grisdanurak, Nurak,Kim, Kyoung Woong Springer-Verlag 2010 Environmental geochemistry and health Vol.32 No.4

Mae Moh Lignite Mine and Environmental Management

Chanin Teparut,Suthipong Sthiannopkao 한국자원공학회 2011 Geosystem engineering Vol.14 No.2

Mae Moh Lignite Mine, in northern Thailand, is the largest open-pit lignite mine in Southeast Asia. It is designed to produce some 16 million tons of lignite per year, to meet the 2400 MW requirements of Mae Moh’s mine-mouth thermal power plants. The mine operation causes both direct and indirect environmental impacts on land use, quality of life,forests and wildlife; it has also caused pollution in such forms as dust, noise, water contamination, odors from the spontaneous combustion of lignite and vibration from blasting. Recognized as a significant pollution source, regulations based on environmental impact assessments (EIA) have been stringently applied. The mine’s controlling body has undertaken responsibility for management of all impacts through its Mae Moh Mine Master Plan, an ambitious outline for further development of the lignite resources in Mae Moh Basin. Standard management by ISO 14001, ISO9001, TIS18001 and CSR guidelines is at present under implementation. The transparency of the system has served to increase trust in Mae Moh Mine’s environmental management, while contributing to an awareness of the environmental impacts and the continual efforts to mitigate them.

Utilization of zeolite industrial wastewater for removal of copper and zinc from copper-brass pipe industrial wastewaterA paper submitted to the Journal of Environmental Engineering and Science.

Sreesai, Siranee,Sthiannopkao, Suthipong Canadian Science Publishing 2009 Canadian journal of civil engineering Vol.36 No.4

<P> Utilization of zeolite industrial wastewater as a sorbent and (or) precipitant to remove Cu and Zn from copper-brass pipe industrial wastewater was conducted. These wastewaters were sampled and values for pH, temperature, biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total solids (TS), total dissolved solids (TDS), total suspended solids (TSS), and heavy metals were determined. In addition, the sorption isotherms of Cu and Zn in copper-brass pipe industrial wastewater onto solids of zeolite industrial wastewater at various dilutions of copper-brass pipe industrial wastewater were explored. The relationship between Cu and Zn concentrations and their removal efficiencies under different conditions of wastewater pH, contact times, and ratios between copper-brass pipe industrial wastewater and zeolite industrial wastewater was examined. Zeolite industrial wastewater contained various carbonate compounds that contributed to high pH and TDS values, and low heavy metals contamination whereas copper-brass pipe industrial wastewater had a low pH value and was contaminated with heavy metals, especially Cu and Zn. Application of zeolite industrial wastewater significantly increased the pH of copper-brass pipe industrial wastewater and consequently removed Cu and Zn. The increase in pH of the wastewater mixture significantly enhanced the heavy metals removal. The Langmuir equation described sorption isotherms of Cu and Zn onto solids of zeolite industrial wastewater at neutral pH (6-7) while the Freundlich equation fitted well at pH @@>@@ 12. The maximum Cu (97%-98%) and Zn (92%-96%) removal efficiencies occurred at the original pH 12.8 of zeolite industrial wastewater, at the ratio of copper-brass pipe industrial wastewater to zeolite industrial wastewater 3:1 (vol.:vol.) and at 30 min contact time. </P>

Anthropogenic influence on surface water quality of the Nhue and Day sub-river systems in Vietnam

Hanh, Pham Thi Minh,Sthiannopkao, Suthipong,Kim, Kyoung-Woong,Ba, Dang The,Hung, Nguyen Quang Springer-Verlag 2010 Environmental geochemistry and health Vol.32 No.3

Development of Water Quality Indexes to Identify Pollutants in Vietnam’s Surface Water

Thi Minh Hanh, Pham,Sthiannopkao, Suthipong,The Ba, Dang,Kim, Kyoung-Woong American Society of Civil Engineers 2011 Journal of environmental engineering Vol.137 No.4

Statistical assessment for spatio-temporal water quality in Angkor, Cambodia

Ki, Seo Jin,Kang, Joo-Hyon,Lee, Young Geun,Lee, Yun Seok,Sthiannopkao, Suthipong,Kim, Joon Ha IWA Publishing 2009 Water Science & Technology Vol.59 No.11

<P>Comprehensive water quality monitoring was conducted to assess the water quality conditions and to determine the impact of urban infrastructure on ambient water quality in Angkor, Cambodia. During this study, surface water, groundwater, and sediment samples were collected for two distinctive seasons in 2006-2007 at 58 monitoring sites along and near the Siem Reap River, in Tole Sap Lake (TSL), and West Baray, the primary water resources in this region. To assess the seasonal and spatial variability of 27 water quality parameters, multivariate analysis of variance, hierarchical cluster analysis, and the Kruskal-Wallis test were conducted using the obtained data. Differences and relationships between the surface water and groundwater were also investigated using t-test and correlation analysis, respectively. The results of these tests showed that the bacterial indicators need special attention as the urban infrastructure of the downtown area caused increased levels of these bacterial indicators in both surface water and groundwater. However, for most parameters, though surface water showed strong seasonal variations, groundwater presented relatively stable conditions between seasons (p&gt;0.05) with site-specific geochemical conditions. Sediment quality illustrated that pollution levels of 10 trace metals were the highest in TSL because of its unique characteristic (river with backward flow), but did not reflect any potential enrichment from urban development. Overall, the results reveal that while the urban infrastructure in this region has not significantly affected most of the water quality parameters, bacteria and coliphages are still a main concern due to their contributions in widespread waterborne diseases. Thus, careful mitigation plans for reducing each pollutant source are needed in the Angkor area.</P>

Analysis of variation and relation of climate, hydrology and water quality in the lower Mekong River

Hanh, Pham Thi Minh,Anh, Nguyen Viet,Ba, Dang The,Sthiannopkao, Suthipong,Kim, Kyoung-Woong IWA Publishing 2010 Water Science & Technology Vol.62 No.7

<P>In order to determine the influence of climate and hydrology on water quality of the lower Mekong River, the long term monitoring data (from 1985 to 2004) of climatic, hydrological and water quality variables were analyzed. In general, water quality was ‘good’ or ‘very good’ for most of the investigated water quality parameters including DO, pH, conductivity, nitrate, phosphate and total phosphorus. All climatic and hydrological elements as well as most of the water quality parameters varied seasonally. Throughout the 18-year period, only evaporation, water level and TSS showed a significant pertinent trend. ARIMA models results reveal that among climatic and hydrological paremeters, water quality could be effectively predicted from the data of discharge flow and precipitation. The results showed good R2 (≥0.7) estimation between predicted and observed values for TSS, alkalinity and conductivity which are the chemically and biologically conservative parameters. For other water quality parameters such as Ca2 + , Mg2 + , Si, Cl−, NO3−, and SO42−, the predicting results by ARIMA model were reliable in shorter period than the above three mentioned variables.</P>

Dietary exposure and human risk assessment of phthalate esters based on total diet study in Cambodia

Cheng, Zhang,Li, Han-Han,Wang, Hong-sheng,Zhu, Xue-Mei,Sthiannopkao, Suthipong,Kim, Kyoung-Woong,Yasin, Mohamed Salleh Mohamed,Hashim, Jamal Hisham,Wong, Ming-Hung Elsevier 2016 Environmental research Vol.150 No.-

<P><B>Abstract</B></P> <P>Phthalate esters are used in a wide variety of consumer products, and human exposure to this class of compounds is widespread. Nevertheless, studies on dietary exposure of human to phthalates are limited. In this study, to assess the daily intakes of phthalate esters and the possible adverse health impacts, different food samples were collected from three areas of Cambodia, one of the poorest countries in the world. The ∑phthalate ester concentrations in Kampong Cham, Kratie and Kandal provinces ranged from 0.05 to 2.34 (median 0.88) μgg<SUP>−1</SUP>, 0.19–1.65 (median 0.86) μgg<SUP>−1</SUP> and 0.24–3.05 (median 0.59) μgg<SUP>−1</SUP> wet weight (ww), respectively. Di-2-Ethylhexyl phthalate (DEHP) and diisobutyl phthalate (DiBP) were the predominant compounds among all foodstuffs. The estimated daily intake (EDI) of phthalate esters for the general population in Kampong Cham, Kratie and Kandal was 34.3, 35.6 and 35.8μgkg<SUP>−1</SUP> bw d<SUP>−1</SUP>, respectively. The dietary daily intake of DEHP, benzylbutyl phthalate (BBP) and di-n-butyl phthalate (DBP) in Kampong Cham, Kratie and Kandal were below the tolerable daily intakes (TDI) imposed by the European Food Safety Authority (EFSA) and reference doses (RfD) imposed by The United States Environmental Protection Agency (USEPA). Rice contributed the greatest quantity of DEHP to the daily intake in Cambodia so may deserve further exploration. To our knowledge, this is the first study to investigate the occurrence and the daily intakes of phthalate esters in Cambodia.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Phthalate esters concentration in daily foodstuffs collected from Cambodia. </LI> <LI> Investigate the bioaccessbility of phthalate esters via the foodstuffs consumption. </LI> <LI> Health risk evaluation of dietary exposure to phthalate esters. </LI> </UL> </P>

Development of enhanced groundwater arsenic prediction model using machine learning approaches in Southeast Asian countries

Park, Yongeun,Ligaray, Mayzonee,Kim, Young Mo,Kim, Joon Ha,Cho, Kyung Hwa,Sthiannopkao, Suthipong Informa UK (Taylor Francis) 2016 Desalination and Water Treatment Vol.57 No.26

<P>Groundwater contamination with arsenic (As) is one of the major issues in the world, especially for Southeast Asian (SEA) countries where groundwater is the major drinking water source, especially in rural areas. Unfortunately, quantification of groundwater As contamination is another burden for those countries because it requires sophisticated equipment, expensive analysis, and well-trained technicians. Here, we collected approximately 350 groundwater samples from three different SEA countries, including Cambodia, Lao PDR, and Thailand, in an attempt to quantify total As concentrations and conventional water quality variables. After that, two machine learning models (i.e. artificial neural network (ANN) and support vector machine (SVM)) were applied to predict groundwater As contamination using conventional water quality parameters. Prior to modeling approaches, the pattern search algorithm in MATLAB software was used to optimize the ANN and SVM model parameters, attempting to find the best parameters set for modeling groundwater As concentrations. Overall, the SVM showed the superior prediction performance, giving higher Nash-Sutcliffe coefficients than ANN in both the training and validation periods. We hope that the model developed by this study could be a suitable quantification tool for groundwater As contamination in SEA countries.</P>