Polycyclic aromatic hydrocarbons (PAHs), abundant in mixed contaminant sites, often coexist with heavy metals. The fate and remediation of PAHs depend heavily on the sorption and desorption behavior of these contaminants. The sorption behavior can in turn be highly affected by certain soil components and properties, such as soil organic matter (SOM) and the presence of heavy metals. Through review of the literature focused on research from 2006 to 2018, this paper discusses interactions, challenges, influencing factors and potential synergies in sorption/desorption of mixed PAHs and heavy metal contamination of soil. The presence of either natural organic matter or heavy metals can enhance the sorption capability of fine soil, retarding the PAHs in the solid matrix. The co-existence of SOM and heavy metals has been reported to have synergistic effect on PAHs sorption. Enhanced and surfactant desorption of PAHs are also affected by the presence of both SOM and metals. Remediation techniques for PAHs removal from soil, such as soil washing, soil flushing and electrokinetics, can be affected by the presence of SOM and heavy metals. More detailed studies on the simultaneous effects of soil components and properties on the sorption/desorption of PAHs are needed to enhance the effectiveness of PAHs remediation technologies.

Emerging contaminants are distributed in to the environment from various anthropogenic activities. These Emerging contaminants (ECs) are mainly composed of products, such as pharmaceuticals, personal care products (PCPs), surfactants, plasticizers, pesticides etc. The present conventional system of waste treatment are not designed to treat these contaminants. Complex structure of these pollutants and their existence at low concentration makes them untraceable and hence found to be difficult in removal of these by present waste treatment. These chemicals are considered as threat to human health and environment. Therefore, disposal and treatment of these chemicals of emerging concern have been a key concern in the field of water treatment and its reuse. Biosensors can be used for biomonitoring of these contaminants with of biological system. Bioremediation plays an important role in the treatment of these pollutants of emerging concern. This review discusses about the sources, effects, and challenges in biomonitoring and bioremediation related to these emerging contaminants.

In this research, a response surface methodology (RSM) was used to investigate the effects of independent parameters (pH, contact time, temperature, adsorbent dosage, and initial concentration of pollutant), their simultaneous interactions, and quadratic effects on crystal violet adsorption onto two starch based materials in the form of batch experiments. The characterizing results indicated that there is no significant difference between the potato starch and synthesized starch phosphate, as phosphorylation has not changed the crystalline structure of starch inside the granules. The maximum removal efficiency of crystal violet ions was obtained 99 % at the optimum adsorption conditions of initial concentration 213.54 mg/L, adsorbent dosage 0.25 g, contact time 14.99 min, temperature 15 °C, and initial pH of solution 9. RSM outputs showed that the maximum adsorption of crystal violet ions by could be achieved by raising pH and adsorbent dosage, and decreasing the initial crystal violet concentration. While temperature and contact time are not effective parameters in crystal violet removal from aqueous solutions using synthesized starch phosphate. Generally, the RSM model is suitable to optimize the experiments for dye elimination by adsorption, where the modified starch phosphate would be an effective adsorbent for treating crystal violet solution.

The present study aims at investigation of the performance of nanofibrous filter, containing magnesium oxide (MgO) nanoparticles, for bioaerosols removal from the air stream. It synthesizes two types of polyacrylonitrile (PAN) and PAN/MgO nanofibers via electrospinning technique, and investigates the antibacterial properties of the produced nanofibers through disk diffusion. The air containing staphylococcus epidermidis is introduced into the filter test rig by a nebulizer and air sampling from the microorganisms takes place before and after the filters by means of a cascade impactor with blood agar culture medium, with the filters, themselves, examined at two states of UVC radiation and dark. The mean diameters of PAN/MgO and PAN are 221.38±65.56 nm and 320.25±87.35 nm, respectively, with the mean length of the inhibition zone for these nanofibers calculated as 0 (for PAN) and 2.8 mm (for PAN/MgO). It turns out that the mean percentage of filtration efficiency is higher in case of PAN/MgO than PAN nanofiber filter; however, the former displays higher mean pressure drop than the latter. For both types of nanofibers under UVC radiation, the mean percentage efficiency for bioaerosol removal is higher than in the dark.

Limited available water resources have rendered wastewater reuse an important issue to specialists in most developed countries, today. The current study works on membrane filtration for treatment of industrial wastewater. By comparing the two methods of membrane bioreactor (MBR) and hybrid membrane electro bioreactor (MEBR) processes, it finds that earlier fouling in the membrane occurs in the first method than the second one. In the membrane electro-bioreactor, in addition to membrane filtration and activated sludge process, the chemical process of electrical coagulation is performed concurrently, wherein the final product quality is improved and the fouling, reduced. In comparison to membrane bioreactor, this method is capable of removing higher percentage of chemical oxygen demand (COD) as an index of organic matters. Accordingly, it is recommended to use the membrane electro-bioreactor method as an alternative to membrane bioreactor for advanced wastewater treatment.

In Thailand, RSS chamber of community-level rubber cooperatives can be classified into two models: old and new model, named after the years of their establishment. Hot gas as a heat supply from Para-rubber (PR) wood (Hevea brasiliensis) combustion is used for removing moisture from the natural rubber (NR) sheets. Smoke and soot particles from PR wood burning has effected to the quality of the NR sheet and the pollution in the workplace area and lead to health problems of the worker. Cascade impactors are equipment for measuring the smoke and soot particles size distribution from PR wood combustion. PAHs compounds from PR wood combustion were found 15 different PAHs components (Tekasakul et al., 2005; Furuuchi et al., 2006). Important methods in decreasing smoke and soot particles from combustion of PR wood for rubber smoking chamber are separation equipment and ventilation designed by computational fluid dynamics (CFD) technique. In this article, the separation method is focused on smoke and soot particle collection to maintain the quality of the NR sheet. This equipment is reviewed both indoor and outdoor, for example, an impaction wall, electrostatic precipitator, stainless-wire, etc. This review indicates that the ESP installing between the furnace and the smoking chamber is suitable to eliminate aerosol particles at the rubber smoking industry. In addition, CFD technique reports is aimed at collecting aerosol particles for decreasing smoke and soot particles emission from rubber smoking chamber is presented.

Untapped pine needles with high potential for energy generation in the hilly area are not only a waste of resource but also increase the chance of environmental hazards as forest fires and GHG emission. This study is conducted to propose a new hybrid system (PV/Wind/Biomass) using abundant pine needle resource as a replacement of existing roof-mounted PV/wind hybrid system and analyse the feasibility using Hybrid Optimization of Multiple Energy Resources (HOMER). Biomass gasifier is integrated to meet the increased load demand of 29.5 kW from 4.3 kW at the Centre for Energy and Environment Engineering building in NIT-Hamirpur. Both cases (with and without storage) has been considered in this research study. New optimized configuration is found to be a 1kWp PV array, one wind turbine of capacity 5kW, gasifier with a 17 kW capacity, 10 numbers of 12v batteries connected in series and 10 kW converter. The comparative analysis of off-grid hybrid systems shows that the system with the storage unit was more economical with 0.222 $/kWh as the cost of energy generation compared to the system without storage unit. The proposed hybrid system is found more reliable, economical and environment friendly and save about 27815 kg of CO2 per year when only diesel is used to meet the same energy demand. Therefore, biomass gasifier in decentralized small-scale power plants can be a better replacement for diesel generators.

This study aims to present a sustainable environmental model using the life cycle sustainability assessment (LCSA) method in Shazand Petrochemical Company. To determine the evaluation indices, two Delphi and DEMATEL-FTOPSIS questionnaires were distributed among 27 and 8 experts in the field of sustainable environmental management. The environmental, social, economic, environmental-economic, socio-environmental and socio-economic factors were selected as the main criteria based on the previous studies. Data analysis was performed using the DEMATEL-FTOPSIS approach. The values of the determined indices were specified by this study, and the management of the company was prepared. The indicated that the BOD/COD output from the company with the value of 2.181 has the highest effectiveness. Moreover, the index of having short - and long-term planning for local sustainable development with the value of 2.416 had the highest influence. Identification of powerful, strategic and high-quality contractors to enter a long-term contract with them in order to get the competitive advantage in the value chain of the company with the value of 0.569 was found to be the best strategy. Eventually, the sustainable management model for petrochemical industry was presented based on the output results. In this model, indices, prioritizing improvement plans and assessing life cycle sustainability were identified as the most important factors among others.

Algal biorefinery process utilizes every component of algal biomass to produce multiple useful fuel products. In this technique, acid pretreatment of algal biomass hydrolyzes microalgal carbohydrates into fermentable sugars, makes lipids more extractable and a protein part accessible for additional products. In the present study, Chlorella sorkiniana produced higher quantity of biodiesel than Botryococcus braunii and biomass in Botryococcus braunii was higher than the Chlorella sorkiniana. Botryococcus braunii produces 11% more lipid content than Chlorella sorkiniana which was consistent with biomass content. The total sugar (oligomeric and monomeric) yield attained by Combined Algal Processing (CAP) was 89.9%. 29 g/L ethanol was produced during the fermentation in the Pretreated Algal Slurry. The recovery of lipids from CAP was reported as 84–89% after fermentation and ethanol removal. CAP preserves the PUFA (Poly-Unsaturated Fatty Acids) and utilizes these high-value PUFAs to further reduce the cost of biofuel production and replace petroleum products.

The changes in diatom assemblages along an urban-to-rural gradient were characterized to assess the ecological status of the Sai Gon River, Vietnam. Diatoms and physico-chemical variables were measured at 10 stations during dry and rainy season. One-way ANOVA showed that diatom metrics and physicochemical variables were significantly different (p < 0.05) between the upper course sites and both the middle- and the lower sites. However, no significant differences were observed between the middle course sites and the lower course sites. Achnanthidium minutissimum and A. exigua were potential indicators of low nutrient in the upper course sites; Melosira granulata and Navicula viridula were preferred moderately eutrophic water in the middle course sites; while Navicula cryptocephala and Nitzschia palea were tolerant to very heavy pollution and dominant in the lower course sites. Canonical correlation analysis (CCA) results showed that concentration of TSS, TN, TP, BOD5 and COD were the most important factors in structuring benthic diatom communities in the Sai Gon River. The results of this study indicated that diatom community was sensitive to changes in urban condition and could be used as an indicator of urbanization.