Sanya Sirivithayapakorn

A key novelty of this work lies in the demonstrating that a single biomass-derived low-cost materials can possess multifunctionality for wastewater treatment, antibacterial activity, and electrochemical performance. In this work, a novel CaCO3/g-C3N4 composite photocatalyst was successfully developed through a simple thermal calcination methods using melamine and waste eggshells as primary precursors. The composite photocatalytic efficiency was assessed by degrading 95.83% of the Methylene blue (MB) under visible light exposure and their electrochemical performance of the CaCO3/g-C3N4 composite showed a significant improvement in capacitance behaviour. The findings confirm that the material exhibits a specific capacitance of 196.66 F g⁻¹ at a current density of 3 mA. In addition, the material was also effective against K. pneumoniae and S. aureus bacteria. This activity is attributed to the release of reactive oxygen species (ROS), which prevented bacterial growth. These results indicate that the composite prepared by a simple and sustainable method offers multifunctional applications and contributes to circular resource management by using biomass waste as a raw material.

This research investigates suitable bio-carriers for the anaerobic ammonium oxidation (anammox) process. This study evaluates the efficiency of the anammox process by assessing nitrogen removal efficiency using five different bio-carriers: fine and coarse polyurethane (PU) sponges, a melamine sponge, Scotch Brite, and a loofah. Among the tested carriers, the reactor of the fine PU sponge media exhibited the highest nitrogen removal efficiency, achieving an 87% removal rate. This high efficiency was attributed to the substantial biomass containment, evidenced by a measured mixed liquor volatile suspended solids (MLVSS) amount of 1414 mg/L. Subsequently, the fine PU sponge, exhibiting the highest efficiency, was selected for further modification with a polyvinyl alcohol–sodium alginate (PVA-SA) gel coating to study the impact of methanol inhibition on nitrogen removal efficiency. An optimal modification condition was determined, utilizing concentrations of 8% PVA and 1.8% SA for the fine PU sponge media. The modified PU reactor exhibited the highest resistance to methanol inhibition, followed by the attached growth fine PU sponge reactor and suspended growth reactor. These findings suggest that there are benefits to using modified PU media for the anammox process in the field.

Deliberate open burning of crop residues emits greenhouse gases and toxic pollutants into the atmosphere. This study investigates the environmental impacts (global warming potential, GWP) and economic impacts (net cash flow) of nine agricultural residue management schemes, including open burning, fertilizer production, and biochar production for corn residue, rice straw, and sugarcane leaves. The environmental assessment shows that, except the open burning schemes, fossil fuel consumption is the main contributor of the GWP impact. The fertilizer and biochar schemes reduce the GWP impact including black carbon by 1.88–1.96 and 2.46–3.22 times compared to open burning. The biochar schemes have the lowest GWP (− 1833.19 to − 1473.21 kg CO₂-eq/ton). The economic assessment outcomes reveal that the biochar schemes have the highest net cash flow (222.72—889.31 US$₂₀₂₂/ton or 1258.15–13409.16 US$₂₀₂₂/ha). The expenditures of open burning are practically zero, while the biochar schemes are the most costly to operate. The most preferable agricultural residue management type is the biochar production, given the lowest GWP impact and the highest net cash flow. To discourage open burning, the government should tailor the government assistance programs to the needs of the farmers and make the financial assistance more accessible.

It is globally recognized that climate change is increasingly affecting sustainable development. Given these challenges, it is imperative to incorporate climate change considerations as part of Strategic Environmental Assessment (SEA), a tool used for sustainable development and planning strategies. The Thai government is in the process of developing river basin management schemes and updating SEA for all the river basins in the country. Considering climate change in future development planning processes would ensure that the outcomes enable more sustainable development. In this article, SEA reports for Thai river basins that have been completed were examined to determine if climate change was considered and how it was done. Analyses were conducted for each of the four phases of SEA, i.e., establishing the context for SEA, implementing SEA, informing, and influencing decisions, monitoring and evaluating plans. The checklist criteria were used to analyze climate change impacts in the river basin SEA reports, focusing specifically on climate change or global warming impacts that lead to serious disasters in the river basins. The results showed that 7 out of the 9 reports currently consider climate change impacts, but not in all phases of the SEA. The linkage of climate change impact analyses between the different phases was weak. There were only 4 reports that sufficiently considered climate change impacts in the second phase of the SEA. These reports used both qualitative and quantitative tools that were appropriate for predicting climate change impacts and with a link to the third and fourth phases. As a result, most of the SEA reports were insufficient in considering climate change impacts. Download : Graphical abstract

The PCLake model has not previously been used for tropical reservoirs. This study attempted to apply the PCLake model to predict the chlorophyll a concentrations (Chl-a) in a tropical reservoir in Thailand. Sensitivity analyses were performed for the constants affecting the prediction of Chl-a in the phytoplankton module. The model calibration was performed by using the adjusted value of the most sensitive constant with the observed data from July to December 2020. The effects of the initial trophic state of the reservoir on the simulated Chl-a were evaluated. The results showed that Chl-a were sensitive to six constants. Among these constants, the value of the specific extinction of detritus (cExtSpDet) was adjusted using the calculated values from the typical limnological parameters of the studied reservoir. Statistical analyses of the results of calibration and the subsequent validation with the observed data from February to September 2022 were listed as follows: NSE=0.55 and 0.37, RSR=0.67 and 0.79, and PBIAS=27% and 9%, respectively. The initial trophic state of the reservoir had no influence on the long-term prediction of Chl-a. This preliminary effort indicates that the PCLake model can be used to predict Chl-a, which is representative of algal biomass in tropical reservoirs and is essential to water quality models, without complex modifications.