Water Resources and Industry最新文献

Long term (200 h) continuous operation of a submerged photocatalytic membrane reactor utilizing direct contact membrane distillation (SPMR-DCMD) is presented. Various types of feed contaminated with ketoprofen were treated: brackish water (BW), seawater (SeaW), and secondary wastewater effluent (SE). Ketoprofen decomposition after 24 h exceeded 99.5 %, regardless of feed type. The distillate showed no toxicity to Aliivibrio fischeri. A significant decrease in flux after 100–124 h of BW and SeaW treatment occurred due to scaling, while for SE the flux remained almost constant for 200 h. This indicates that a shorter study would not allow a proper analysis of the process. A scaling layer was formed regardless of feed type, and the formation of CaSO₄⋅2H₂O, CaCO₃ or (Ca,Mg)CO₃ was proved. The porous structure of the deposit during SE treatment prevented significant flux deterioration. The formed TiO₂ layer protected the membrane from damage by the growing salt crystals.

In light of observed climate change dynamics, including intensified precipitation events, prolonged arid spells, and elevating sea and ocean levels, water supply infrastructures face escalating challenges. Some regions are facing significant damage, with failures in network components leading to losses of up to 30 %, while globally, can escalate to tens of millions of cubic meters of water. The spatial analysis of energy consumption in abstraction, transmission, and treatment processes per cubic meter of water carried out in this article highlights the impact of climate change on the choice of specific unit process methods. Consequently, clarifying the complex interaction between water and energy attempted in this work assumes paramount importance in ecological and economic water supply network planning.

The converter valve of ultra-high-voltage direct current grid requires a large amount of cooling water for heat dissipation. Considering the generated waste heat, this study proposes a heat pump-driven mechanical vapor compression (HP-MVC) desalination system based on traditional power-driven mechanical vapor compression (MVC). Using the scaling-endoreversible thermodynamic model, the analytical solutions of the structural equation and operating boundary of the proposed HP-MVC system were derived, which is the innovation of this study. The effects of different component parameters on the thermodynamic characteristics and operation boundaries of the HP-MVC were determined. The results revealed that the HP-MVC system alternately exhibited heat-drive dominant and power-drive dominant modes, in which the specific power consumption was lower in the former. When the recovery ratio was 0.3, with an increase in the pressure ratio from 1.15 to 1.50, the heat supplemented by the heat pump decreased by 31.9 %, and the specific power consumption increased by 63.1 %. The analytical solutions of the structural equation provide a theoretical basis for the efficient operation of the system, and the operation boundaries demonstrate the difference between HP-MVC and traditional MVC. The HP-MVC reduces heat dissipation requirements and results in a more energy-efficient desalination system, which is a typical mutually beneficial design and worth promoting.

In this paper a new renewable energy source was proposed based on rain power. Rain energy was not used as an energy source up to now; so, in this research its applicability was investigated as a green large scale power source. Hence, three innovative mechanisms were presented to harvest the energy of rain. Firstly, the kinetic energy of rain drops was converted to electricity using piezoelectric harvesters designed and named as Pizo-panel collectors. Secondly, potential energy of collected rainwater was enhanced by utilizing designed towers and converted to electricity using a water turbine. Thirdly, collected water was used in osmotic power units to generate electricity from the salinity gradient of that rain water and brine. The results show that generated power in the presented power plant named as rain power plant, was considerable and can be used for diversifying of energy basket. In addition to power generation, collected water in the rain power plant can be used for supplying urban and agricultural need for water. The presented power source not only does not have destructive impacts on the environment, but also helps the soil to prevent it from splash and crusting erosion. The results showed that total global annual rain energy potential amount was estimated to be 3.44 × 10⁸ GW h which is comparable with global potential of solar energy. Also, the results showed that for rainy areas with an annual rainfall of 200 cm, 2.59 kW h/m² could be produced, which is equal to 51.7 MW h for an area of 200,000 m².

One major issue with MED-TVC systems, a widely used thermal-based desalination technology, is their high energy consumption and carbon emissions. This underscores the importance of optimising and integrating these thermal-based desalination technologies with sustainable energy systems to utilize their waste heat and enhance the performance of these plants effectively. This research aimed to optimize and address the environmental challenges of MED-TVC desalination plants in areas with insufficient sunlight, unstable weather conditions, and limited economic resources. To this end, a model of an electric heater for generating thermal energy coupled with an optimized MED-TVC desalination plant was proposed. The MED-TVC section was optimized by incorporating an additional ejector in the final stage of MED-TVC demonstrating an increase of over 11 % in evacuating non-condensable gases from the last effect and increasing the product water by up to 14.89 %. Regarding the design of the electric heating elements used in electric heaters, the use of one-plus-two U-tubes with helical baffles was more efficient than multi-layer U-tubes with segmental baffles as improved the pressure loss of the thermal fluid by 25 % and increased the heat transfer coefficient of the heating elements to 18 %. The power section was also equipped with an off-grid system to provide the necessary power for the equipment of the proposed model. In the economic analysis of employing a parabolic trough solar collector and electric heaters, not only were the direct costs of the electric heaters almost equal to just 40 % of the direct costs of the parabolic trough solar collector approach but also the required thermal fluid was 50 % of the solar case.

Sugarcane bagasse (SB) was used to produce a new bioadsorbent (STEA), drawing on circular economy concepts. STEA was synthesized using a two-step one-pot reaction, employing epichlorohydrin and triethylamine in the presence of N,N-dimethylformamide, without the use of a petroleum-based catalyst. The structure and surface of STEA were characterized by elemental C, H, N, and Cl analysis, X-ray diffraction, infrared spectroscopy, ¹³C solid-state nuclear magnetic resonance spectroscopy, thermogravimetric analysis, specific surface area and pore size distribution determination, and point of zero charge measurement. Batch adsorption and desorption tests were performed with the model dye Remazol Golden Yellow (RGY) RNL, a reactive anionic azo dye widely used in textile industry, to evaluate the potential reuse and application of STEA in a fixed-bed column for wastewater treatment. For batch adsorption, the best dose and agitation speed were 0.2 g L⁻¹ and 50 rpm, respectively. STEA effectively removed RGY over a wide range of pH (2.00–10.00). The equilibrium time, maximum adsorption capacity (Q_max), and desorption efficiency (E_des) were 720 min, 369 mg g⁻¹ (0.71 mmol g⁻¹), and 49.5 %, respectively. The fixed-bed column fed with a spiked aqueous RGY solution could be operated for 415 min, with Q_max of 422 mg g⁻¹ (0.81 mmol g⁻¹) and E_des of 58.9 %. Batch and continuous experiments using real textile industry wastewater containing reactive azo dyes showed high color removal efficiency by STEA, with no interference of other compounds present in wastewater on adsorption of the reactive azo dyes (overshooting effect). The technology was validated in a relevant environment and achieved technology readiness level 5, showing potential to be upscaled. Therefore, STEA proved to be an efficient bio-based technology for application in tertiary treatment of real textile plant wastewater to remove reactive anionic azo dyes.

Pulp and paper mill effluents represent a significant environmental concern due to the presence of various toxic organic and inorganic pollutants, posing risks even at low concentrations. With the paper production process consuming approximately 200 tons of water per ton of paper and generating effluents containing over 250 different chemicals, effective treatment methods are essential to mitigate the environmental impact of the pulp and paper (PP) industry. This study presents a comprehensive evaluation of the efficacy of heterogeneous and homogeneous photocatalytic treatments for PP industry-derived effluents, targeting reductions in major pollutant concentrations below environmental standards. A thorough review of the literature on pollutant removal from PP effluents using photocatalytic treatment, particularly employing UV/TiO₂ and UV/ZnO photocatalysts, reveals significant removal rates. Doped photocatalysts have shown enhanced performance, achieving removal percentages of 98 % for BOD and COD, and 99 % for color and lignin. Additionally, Fenton and photo-Fenton treatment techniques have demonstrated high removal efficiencies for BOD, COD, color, and lignin.

Seawater desalination has become an accessible option for augmenting freshwater supplies worldwide. In the countries of the Gulf Cooperation Council (GCC), it has been practiced for decades as the main source for domestic water use. Sustainable desalination requires addressing environmental impacts including damage to ecosystems from the high volumes of brine in the Gulf. This paper examines challenges related to environmental regulation of brine management in the Arab Gulf countries using the example of Qatar. It analyzes the brine challenge through infrastructure planning policies and stakeholders’ perceptions. The brine issue has been identified as a major environmental concern that requires action through discharge infrastructure, brine management technologies, and regulatory approaches based on quality thresholds and monitoring systems. Although there is a high level of agreement on the solvability of the brine issue, there are limitations with regard to the high reliance on desalination rendered through large-scale infrastructure. These limitations necessitate complementary water supply infrastructure for storage or the development of other sources through water reuse and storage. While water security considerations require prioritization of protection and supply continuity through desalination, incremental change through a stepwise dual approach of brine management and regulation is still possible.

Sequencing batch moving bed biofilm reactors have been widely used in commercial wastewater treatment facilities for organic carbon and nitrogen removal. However, these reactors can remove low phosphorus (P) levels. Therefore, this study investigated the potential of SB-MBBRs for maximizing simultaneous nitrification-denitrification and P removal (SNDPR) potential from P-rich municipal wastewater impacted by industrial discharges. A series of experiments were carried out to investigate the effect of external volatile fatty acid (VFA) dosing, airflow rate, and temperature on SNDPR using pilot-scale SBMBBRs. Stable and robust SNDPR was achieved with an optimum acetic acid supply of 150 mg SCOD/L, at 20 ^oC and 2.5 L air/min. A low airflow rate (AFR) and high-temperature conditions affected P release and uptake kinetics. Efficient PHA storage, dissolved oxygen (DO) transfer (outer layer), DO diffusion limitation (inner layer) of biofilm, and conversion of NH₄-N to NO₂-N/NO₃-N enhanced SNDPR in the two pilot SB-MBBRs.

Natural manganese oxides (n-MnOx) widely exist in the nature and may contribute to the elimination of organic contaminants. The present study investigated the degradation of frequently detected fluoroquinolone antibiotic enrofloxacin (EFX) and the degradation kinetics were analyzed. During the reaction, the valence of Mn in n-MnOx changed with the release of Mn ions. It was also found that combing manganese oxidizing bacteria with n-MnOx can enhance the degradation of EFX and alter the degradation pathway as well. The transformation products of EFX were analyzed with UPLC-MS/MS, which revealed seven products. Based on them, it is proposed that the degradation may start with the dehydrogenation from the piperazine moiety that was further broken down. Respirometry tests demonstrated that the degradation with n-MnOx significantly reduced the toxicity of EFX. This study proved the oxidation with n-MnOx as a simple and effective technology to remediate the contamination of enrofloxacin and other fluoroquinolones and the potential of combing the special capacity of microorganisms.