Purpose Chiang Rai is the northernmost province of Thailand. Municipal solid wastes (MSWs) was generated 430,828.2 ton/y in this area; however, only 24 percent of waste was properly disposed, and 43 percent of waste was properly managed. The purpose of this paper is to explore knowledge, attitudes and practices (KAP) of highland residents in order to provide a basis for the development of waste management in the study area. Design/methodology/approach A cross-sectional study was conducted in Mae Fah Luang district, Thailand, from November 2016 to January 2017. A random sample of 451 respondents constituted the study population. Data were gathered using a structured questionnaire. Pearson Correlation and χ2 were applied to identify the association among variables. Findings Overall, 73 percent of respondents had high level of knowledge; 85 percent of respondents showed neutral attitude; and 59 percent of respondents performed moderate practice on MSW management. The results highlighted that age and education levels were statistically significant associated with KAP levels on MSW management at (p=0.05). Originality/value The respondents who have good knowledge also have a good level of practice; and those who have good attitude also have a good level of practice. Socio-demographic factors and suitable way to promote an effective MSW management should be considered.

Textile wastewater generally consists of high organic substances and is strongly colored. Reactive dye has been used extensively in the textile industries. It is water soluble and difficult to remove by chemical coagulation. Removal of organic substances simultaneously with dye can be achieved by a biological process. This study aims to investigate the treatability of the organic substances and reactive dye in immobilized-cell sequencing batch reactors (SBR). Three different supporting medias namely activated carbon, steel slag and plastic were used. The performance of each reactor was compared with a conventional sequencing batch reactor. The simulated textile wastewater containing the reactive azo dye Procion Red H-E7B of a concentration of 40 mg/L and COD 300 mg/L, was fed into the reactors. The supporting media in the SBR system, it will enhance the capability of COD and dye operating of the SBRs consisted of 5 periods; Fill 1.5 h, React (anoxic:oxic) 20 (14:6) h, Settle 1.5 h, Draw 0.5 h and Idle 0.5 h. The results revealed that by adding removal. During a steady state of operation, the COD and dye concentrations of each period were investigated. In addition, the prolonged anoxic period brought about better decolorization efficiency.

This study investigated municipal solid waste generation rate and its compositionincluding the level of knowledge, attitude and practice on municipal solid waste (MSW) management of highland rural tourist area in Chiang Rai Province, Mae Salong Nok Sub-district, Thailand in order to propose the guidelines for effective MSW in rural tourist areas. Samples of MSW were collected during weekdays and several weekends, and separated into 4 categories: general,recyclable, organic and hazardous waste. About 40 % of the MSW consisted of organic waste; plastic bags were widely present, comprising more than 60 % of the mass of the general waste group. Level of knowledge, attitude and practice(KAP) on MSW was evaluated using questionnaires. While respondents scored 80 % and 76 %, respectively, on their level of knowledge of, and attitude to MSW, practice fell far short at only 37 %. The results led to a recommendation to strengthen waste separation at source, implement waste reduction and recycling concepts to reduce the volume of plastic bags, and introduce composting of food waste. The study also highlights economic and financial benefits of waste recycling. Additional value-added could be derived from the organic waste recycling program by promoting production of bioextracts and compost at household level, in order to reduce the amount of organic wastes and carbon emissions. The general and recyclable wastes could also be converted to energy as refuse-derived fuel 2 (RDF-2); the estimated average heating value of this RDF-2 was 23.56 MJ kg-1. To sustain MSW management in tourist areas, environmental education and environmental awareness campaigns are needed, using the appropriate local languages for communication, and introduction of a fairer system based on the polluter-pays principle for the business sector.

The aim of this study is to investigate the decolorization in anaerobic/aerobic biological activated carbon (A/A BAC) system. The experiment was divided into 2 stages; stage I is batch test for preliminary study of dye removal equilibrium time. The preliminary experiment (stage I) provided the optimal data for experimental design of A/A BAC system in SBR (stage II). Stage II is A/A BAC system imitated Sequencing Batch Reactor (SBR) which consist of 5 main periods; fill, react, settle, draw and idle. React period include anaerobic phase followed by aerobic phase. The BAC main media; Granular Activated Carbon (GAC), Mixed Cultures (MC) and Biological Activated Carbon (BAC) were used for dye and organic substances removal in three different solutions; Desizing Agent Solution (DAS), dye Solution (DS) and Synthetic Textile Wastewater (STW). Results indicate that GAC adsorption plays role in dye removal followed by BAC and MC activities, respectively. In the presence desizing agent, decolorization by MC was improved because desizing agent acts as co-substrates for microorganisms. It was found that 50% of dye removal efficiency was achieved in Fill period by MC. GC/MS analysis was used to identify dye intermediate from decolorization. Dye intermediate containing amine group was found in the solution and on BAC surfaces. The results demonstrated that combination of MC and BAC in the system promotes decolorization and dye intermediate removal. In order to improve dye removal efficiency in an A/A BAC system, replacement of virgin GAC, sufficient co-substrates supply and the appropriate anaerobic: aerobic period should be considered.

Elephant dung biochar (ED350) prepared by controlled heating at 350 ºC was used to adsorb methylene blue (MB) in an aqueous solution. The effects of adsorption time, pH, adsorbent dosage, and initial MB concentration were examined. Kinetic, isotherm, and thermo-dynamic models were then further analyzed to determine the adsorption. The results show that ED350 was found to be efficient within 180 min. The optimum pH of MB adsorption was 11. The Langmuir isotherm model was found to be the most suitable fit for the adsorption equilibrium data, with ED350 having a homogeneous surface. The calculated equilibrium parameter (RL) values were greater than zero and less than one, indicating a favorable adsorption process and that ED350 was an efficient adsorbent for MB removal. The kinetics of MB adsorption onto ED350 obeys the pseudo-second-order model. The results of thermo-dynamic data consideration reveal that the adsorption process is spontaneous and exothermic in nature. This finding suggests that ED350 may prove to be an efficient low-cost adsorbent of MB from wastewater.