Water Resources and Industry最新文献

A condensate generated from air in air conditioning (AC) units is a reliable, and a stable source of water possible to be reused in different forms. This study focuses on condensate recovery from heating ventilation air conditioning (HVAC) systems maintaining ambient or indoor air. The database of experiments conducted in outdoor air is much larger than those conducted in indoor air. The experiments conducted in greenhouses, plant factories, vertical farms, and space systems and applications come with assistance The latter include facilities such as the International Space Station and closed analog ecosystems simulating future space bases. In these locations, condensate is mainly recovered for crew needs (consumption, hygiene, etc.). From these studies it is possible to derive knowledge of what treatment processes are required to obtain water of high quality. In general, the most important parameters affecting the quantity and quality of recovered condensate are climate zone and associated climate parameters, building type, building use, and supply air volume. Additionally in case of indoor air recovery, the most important parameters are the climatic conditions, people activity, plant types grown, and whether the system has to operate in a closed loop. Other important parameters influencing condensate composition is construction and material of the HVAC system and the condensate capture system. The growing interest in the market for vertical farms and closed-loop grow chambers is observed globally. Thus, this study will favor future research on condensate recovery from these facilities. This paper deepens the look at the problem of HVAC condensate recovery by including previously not considered places such as closed ecological systems, where condensate is used for drinking water purposes.

The extraction of olive oil generates considerable volumes of an agricultural by-product, olive mill wastewater (OMWW), which is damaging to the environment and biological life. To investigate the effect of fermented OMWW on number of pods, pod length, pod weight, dry weight of plant, chlorophyll a, chlorophyll b, and total chlorophyll of common bean, plants were grown and irrigated with various percentages of fermented OMWW (0%, 4%, 6%, 8%, 10%, and 100%) in a greenhouse. The study found that irrigating agricultural land with a water mix containing a specified quantity of OMWW enhanced physicochemical parameters and influenced plant characteristics. The plant characteristics were substantially affected when wastewater irrigated agricultural areas with water polluted with OMWW at concentrations no more than 4%. According to the findings of this study, utilizing 4% OMWW resulted in the best bean plant growth response, with an increase in growth indices and photosynthetic pigments.

Small hydropower plants are one of the most important renewable energy sources that do not degrade and consume natural resource. The paper presents a case study of an already operating small hydropower plant (SHP) and a potential increase in its energy production by raising the damming level. Three variants were defined and subjected to detailed analysing. The analyses used the Fuzzy AHP methodology (FAHP), which allowed for identifying the variant that has the best chance of being implemented in the context of administrative, legal and social realities of the country where an SHP is located. The adopted solution will increase electricity production by 108.78 MWh annually, while reducing carbon dioxide emissions by 86000 kg CO₂. The described methodology is of general use and can be applied in any country in the world.

Degradation of bisphenol S was studied using ozone activated by sodium percarbonate and the effectiveness of optimized process was compared with the peroxone process. The influence of several factors including sodium percarbonate concentration, ozone dose, pH, and water matrix were investigated. A synergetic coefficient of 3.84 was achieved for the combination of sodium percarbonate and ozone, confirming the effectiveness of this hybrid process. Scavenging tests revealed, that carbonate radicals, hydroxyl radicals, superoxide radicals, and singlet oxygen contributed to the degradation of bisphenol S. At the same operating condition, degradation effectiveness values of 99% and 81% were obtained by ozone combined with sodium percarbonate and hydrogen peroxide, respectively, demonstrating the superiority of sodium percarbonate over hydrogen peroxide in combination with ozone for the degradation of bisphenol S. Low concentration of inorganic anions had a negligible effect on the degradation, while carbonate ions increased the first-order degradation rate constant by 56%.

Tannery wastewater (TWW) is a toxic and hazardous effluent that causes great harm to receiving ecosystems if released untreated. Here, magnesium oxide nanoparticles (MgO-NPs), synthesized from low-cost and readily available magnesite, were used for the treatment of real TWW under batch laboratory conditions. The optimum treatment conditions were 90 min contact time and 10 g MgO-NPs dosage per L of real TWW, under ambient pH and temperature. Results were underpinned by state-of-the-art analytical techniques, including ICP-OES, XRD, XRF, and FIB/EDS-SEM, along with geochemical modelling (PHREEQC). The removal efficiency for the main contaminants that are typically found in TWW was, from higher to lower score, Fe ≥ U ≥ Cr ≥ Mn ≥ Al ≥ Sb ≥ Cu ≥ Ni ≥ TOC ≥ COD≥ ${SO}_4^{2-}$. The removal percentages for these contaminants were ≥99%, aside from Ni (97%), TOC (71%), COD (69%) and particularly ${SO}_4^{2-}$ (21%). The underlying mechanism for contaminants removal is linked to the scavenging of metals by the MgO-NPs, forming complexes, in combination with alkalinity addition (through MgO dissolution) that lead to contaminants precipitation. The PHREEQC geochemical model confirmed the existence of divalent, trivalent, oxyanions, and multivalent chemical species in MgO-NPs/TWW solution, including complexes. Contaminants attenuation was achieved through precipitation, co-precipitation, adsorption, and co-adsorption, while these were removed as hydroxides, sulfides, carbonates, oxide, and oxyhydrosulfates. Overall, results highlight the great potential of MgO-NPs for the sustainable management of real TWW.

The public water system management in Mexico has recently been criticized due to severe problems with the availability of drinkable water. Significant differences exist between Mexican regions regarding the availability of renewable water and water system distribution. Moreover, water governance in the country is inefficient due to the lack of transparency in the water policies. Therefore, the article aims to investigate whether there is a direct relationship between water system management efficiency and water system improvement efficiency and how the efficiency reflects the size of the population and the availability of renewable water in each state. For this, a two-stage DEA model is constructed to evaluate the water system management efficiency in Mexico. The results indicate high average water management efficiency but very low efficiency in the water system improvements. Furthermore, immense differences in the water system efficiency can be observed with respect to the characteristics and adopted policies.

Water quality in cooling towers of thermal power plants (CTTPP) has a critical role in the operation and maintenance of CTTPP and the need for an index which represents well the quality of water used in CTTPP. In this study, municipal wastewater effluent (MWE) as a source of water for use in the CTTPP was evaluated by determining the water quality index. 22 MWE quality parameters were considered in terms of their potential effects on cooling towers. The relative weight of the parameters is calculated by the analytical hierarchical process (AHP). The analysis of water classification was done by using the fuzzy inference system (FIS). In the fuzzy logic approach, the trapezoidal and triangular membership functions and the Mamdani inference system were used, and the final rules consist of 240 rules. The center-of-gravity method is used for the Defuzzification of the results. The values obtained from the cooling tower effluent quality index (CTEQI) based on the FIS were generally more stable than the values from CTEQI based on the traditional system. The outcomes of this study established that the quality of effluent entering the cooling towers in a Shahid Moftteh power plant in the Hamadan (effluent sampling site) is moderate to good condition (annual fuzzy index 50–90, average annual traditional index 79.52–95.99). This research result reveals that CTEQI can be counted as a general tool for evaluating the quality of effluent that use in the CTTPP and can be used with confidence for this purpose.