Sewage Treatment Technology Research Articles

Research on Automatic Technology of New Urban Sewage Inspection and Treatment

The automatic control technology is more and more widely used in sewage treatment systems. The thesis elaborated on the new urban sewage treatment technology and control process, analyzed the PLC-based sewage treatment control system structure, realized the control of power equipment and testing equipment, and finally completed the remote monitoring of the SBR sewage treatment based on MCGS. Simultaneously, the paper uses big data analysis and statistical methods to analyse and compare the routine monitoring and important monitoring data of sewage treatment, effectively saving monitoring, feedback, improvement, and release time. The actual operation results show that the system is stable and reliable and can remotely monitor and control equipment operation in real-time.

A solvent-responsive robust superwetting titanium dioxide-based metal rubber for oil-water separation and dye degradation

The sewage treatment technology of oil-water separation based on superwetting materials has been widely employed. However, the stability of substrates was rarely considered in the past few years, which greatly limited the application of superwetting materials in engineering field. As a new robust, three-dimensional porous material, metal rubber (MR) has attracted significant attention for solving this problem. To treat the wastewater containing insoluble heavy/light oil and soluble dyes, herein, MR capable of degrading organic dyes with switchable wettability and high oil-water separation efficiency was prepared. Firstly, the superhydrophilic MR was obtained by anodizing. Then, the wettability of MR surface was reversibly switched between superhydrophilic and superhydrophobic via alternate immersion in stearic acid ethanol solution and tetrahydrofuran (THF) solvent to achieve switchable oil-water separation of MR. The superwetting MR displayed excellent abrasion resistance and retained outstanding oil-water separation performance after 100 times of sandpaper abrasion. Besides, the surface of pure titanium MR was rich in titanium dioxide (TiO2) after anodic oxidation, which could effectively degrade the organic dyes under ultraviolet light. Therefore, the as-prepared superwetting MR possesses the ability to treat complex wastewater and have applications prospects in controllable oil-water separation and self-cleaning surfaces.

Rural Domestic Sewage Treatment Technology Application in Conghua District of Guangzhou under the Rural Revitalization Strategy

The paper analyzes the current situation and characteristics of rural domestic sewage treatment in Conghua District, Guangzhou city. It takes the river system as the vein and the administrative village of characteristic town as the node, which pays great attention to the overall planning of the water environment. In this area, the rural domestic sewage on both sides of the Liuxi River is selected as the research object, and the rural sewage treatment of the Yadong River Basin is taken as a project case to explore the applicability of rural sewage treatment technology, hoping to achieve a beautiful countryside with clear water and beautiful scenery, and then promote the revitalization and development of the beautiful village, which provides reference value for ecological and social benefits.

Preliminary Investigation of an Installed Pilot-Scale Biological Nutrient Removal Technology (BNRT) for Sewage Treatment

Water utilities, commercial and industrial establishments are required to upgrade or install new treatment systems to comply with the revised effluent standards issued by the Department of Environment and Natural Resources – Environment Management Bureau (DENR – EMB) which now includes removal and monitoring of nutrients (nitrogen and phosphorus components). One solution is to utilize a biological nutrient removal technology (BNRT) system capable of removing nutrients from sewage. The on-going study aims to investigate the performance of the pilot-scale system in the removal of nutrients from sewage. The designed pilot-scale anaerobic-anoxic-oxic (A2O) process with a total hydraulic retention time of 8.37 hrs. was operated in an existing sewage treatment plant (STP). System modification was adapted to ensure continuous operation. Dissolved oxygen (DO) and temperature of each compartment were evaluated after 45 days of system modification. The DO of the anaerobic and oxic compartment remained within the required range, while the internal recycling flowrate and/or aeration must be adjusted to achieve a DO concentration of 0.20 – 0.50 mg/L in the anoxic compartment. The research is financially supported by the Philippine Council for Industry, Energy and Emerging Technology Research and Development of the Department of Science and Technology (PCIEERD Project No. 04176).

Filamentous fungal in situ biosynthesis of heterogeneous Au/Cd0.5Zn0.5S nano-photocatalyst: A macroscopic assembly strategy for preparing composite mycelial pellets with visible light degradation ability

Visible light degradation is a green and economic technology for sewage treatment receiving widespread attention. Here, the filamentous fungus Phomopsis sp. XP-8 was developed as a bioreactor to successively biosynthesize Cd0.5Zn0.5S quantum dots and gold nanoparticles (AuNPs) in situ and formed heterogeneous Au/Cd0.5Zn0.5S nano-photocatalyst inside cells. This strategy synchronously mediates the microscopic and macroscopic assembly of zero-dimensional materials by microorganisms. The heterogeneous catalyst functionalized composite mycelium pellets (CMP) not only have excellent visible light degradation activity but some unique characteristics. The outstanding organic dye biosorption capacity of CMP increases the contact rate between organic dyes and nano-catalysts, improving catalytic activity. High mechanical strength makes CMP easy to separate and recycle, which overcomes the difficulty of nano-catalyst recovery after use and avoids creating secondary pollution to the environment. This study not only broadens the means of heterogeneous nano-catalyst synthesis but also provides a new perspective on the macroscopic assembly of nanomaterials.

Simulation of water quality data for advanced treatment of domestic sewage in constructed wetlands

With the gradual maturity of sewage treatment technology, constructed wetlands are increasingly employed to treat sewage. In residential areas where people live, there are concentrated sewage discharges. Therefore, the author proposes constructing several small movable constructed wetlands in the community to treat domestic sewage in the community. A 40 cm× 40 cm model was established to simulate the removal effect of pollutants. The influent concentrations of simulated COD, NH4 +-N, NO3 −, TP are 96.01 mg/L, 18.23 mg/L, 14.13 mg/L, 3.00 mg/L, respectively, and the outlet concentrations are 18.25 mg/L, 5.51 mg/L, 3.12 mg/L, 0.32 mg/L, the removal efficiency reached 80.99 %, 69.78 %, 77.92 %, 89.33 %, with good simulation effect. It provides a theoretical basis for the construction of constructed wetland.

Efficiency evaluation of sewage treatment technologies: implications on aquatic ecosystem health

Abstract This research paper tries to identify and address issues related to efficiency of sewage treatment plants (STPs) and their implications on the Dal Lake ecosystem in Srinagar city, Kashmir, India. Fluidized aerobic bioreactor (FAB) and sequential batch reactor (SBR) technologies having been recently installed along the periphery of Dal Lake were evaluated for efficiency for a continuous period of 24 months from December 2016 to November 2018. Apart from chemical quality, total coliform (TC), fecal coliform (FC), and fecal streptococci (FS) analyses were also carried out. Major highlights of our work using one-way ANOVA (analysis of variance) revealed significant variations (p < 0.05) in total suspended solids (TSS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), ammonia (NH3-N), total phosphorus (TP), TC, FC, and FS. Our findings indicate that both technologies are struggling for removal efficiency, which is very low, especially in FAB during three to four months of winter season where a very high drop in the working efficiency of the STP was observed. The treatment facilities did not meet the prescribed standards in respect of TSS, BOD, NH3-N, TP, TC, FC, and FS thereby having the potential to compromise public health and trophic status of Dal Lake.

Treatment and disposal of surface wastewater and Sludge

The main sources of surface wastewater pollution are products of soil washout, destruction of asphalt and so on. Surface wastewater pollutes water bodies with suspended, surface-active substances, oil products, organic impurities, heavy metal ions and other pollutants. Precipitation leads to pollution and siltation of watercourse channels, disrupts the vital activity of living organisms, microorganisms, and has a negative effect on the biocenosis and self-cleaning ability of water bodies. The aim of the study was to develop a technology for treating surface wastewater from coal industry enterprises using a new water filtering facility, a clarifier reactor. The composition of the enterprise’s surface wastewater was studied. A draft of a new wastewater treatment plant and a clarifier reactor were developed. The quality of the treated water corresponded to the requirements. As a result of theoretical and experimental studies, a technology for the storm sewage treatment of industrial enterprises was developed, which allows them to be dumped into open water bodies or used for disposal in industrial water supply enterprises.

Unravelling the economics behind mainstream anaerobic membrane bioreactor application under different plant layouts

This research evaluated the economic feasibility of anaerobic membrane bioreactor (AnMBR) as a mainstream technology for municipal sewage treatment. To this end, different wastewater treatment plant (WWTP) layouts were considered, including primary settler, AnMBR, degassing membrane, partial nitritation-Anammox, phosphorus precipitation and sidestream anaerobic digestion. The net treatment cost of an AnMBR-WWTP decreased from 0.42 to 0.35 € m−3 as the sewage COD concentration increased from 100 to 1100 mg COD L−1 due to revenue from electricity production. However, the net treatment cost increased above 0.51 € m−3 when nutrient removal technologies were included. The AnMBR and partial nitritation-Anammox were the costliest processes representing a 57.6 and 30.3% of the treatment cost, respectively. Energy self-sufficiency was achieved for high-strength municipal sewage treatment (1000 mg COD L−1) and a COD:SO42−-S ratio above 40. Overall, the results showed that mainstream AnMBR has potential to be an economically competitive option for full-scale implementation.

Anthropogenic impacts on nutrient variability in the lower Yellow River

Excessive nutrient discharges and changes in nutrient ratios caused by global change and anthropogenic activities have been reported in global rivers; however, the actual alterations occurring in the Yellow River environment is too fast to catch up with. From 2001 to 2018, dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP) and dissolved silicon (DSi) concentrations showed decreasing trends in the lower Yellow River throughout the study period. Dissolved organic phosphorus (DOP) concentrations increased since 2009, reaching up to 95% of the total dissolved phosphorus. Annual minimum dissolved organic nitrogen concentrations increased with time. We observed extremely low nutrient concentration events since 2014 in response to the retention effect of large reservoirs; this significantly reduced the downstream water discharge and sediment load and increased phytoplankton uptake. To further analyze the variability of nutrient fluxes, we quantified the fluxes to the Yellow River from natural (runoff, precipitation deposition, and sediment load from the Loess Plateau), anthropogenic (recharged water, fertilizer application, and vegetation coverage), social and industrial (population urbanization, GDP, and sewage effluents) sources. The highest contributions of total nutrient fluxes emptied into the Yellow River was fertilizer losing (44–48%) for DIN, sewage effluents (85–88%) for DIP, and runoff (35–65%) for DSi, respectively. Strictly controlling the amount of fertilizer and improving the application methods, improving sewage treatment technology, and vigorously promoting “green travel” might reduce nutrients emptied into the Yellow River based on the main sources of nutrients. Our study may help policy makers formulate strategies and it is possible to own a better water quality in the Yellow River.

Growth and metabolism of an aerobic thermophilic Geobacillus strain under simulated composite extreme reservoir conditions

The growth and metabolism of an aerobic thermophilic Geobacillus strain DM-2 under simulated composite extreme conditions of the Ng3, Gudao Block, Shengli Oilfield (China) with sufficient oxygen and nutrition were investigated. The experimental device for simultaneously simulating the temperature, pressure, salinity, porosity, permeability, fluid characteristics and development status of the target reservoir was designed, where the air assisted flooding technology was used. Particularly, the oxygen demand was estimated according to biotic and abiotic oxygen consumption. Despite the relatively lower rates of microbial growth and metabolism, the strain was able to grow under these conditions with the cell density increased from 106 to 108 cellsmL−1, and CH3COO− produced at the concentration of about 400 mg ⋅ L−1. Aerobic microorganisms, such as Geobacillus sp., may be promising candidates for microbial enhanced oil recovery and oily sewage treatment technology.

Advance in Improving the Electrical Performance of Microbial Fuel Cell

As a bioelectrochemical hybrid system, microbial fuel cell converts chemical energy into electrical energy through microbial metabolism, which has great advantages of energy conservation and environmental protection, high energy conversion efficiency, and reduced sludge volume. Therefore, how to improve the power generation performance and output power of MFC has been a hot topic in recent years. Based on this, on the basis of reviewing many literatures, this review analyzes the main factors influencing the electrical performance of MFC by combining the principle of MFC and its electronic transfer mechanism, including battery reactor structure, exchange membrane, anode microorganisms, electrode materials and parameters, etc. At the same time, the application prospect of MFC is discussed, including CW-MFC coupling technology, biosensor and sewage treatment technology. Finally, the present challenges of MFC are put forward, and a better application research direction is proposed for the future of MFC.

Rapid microwave synthesis of Fe3O4-PVP@ZIF-67 as highly effective peroxymonosulfate catalyst for degradation of bisphenol F and its mechanism analysis

Various metal-based heterogeneous catalysts activated peroxymonosulfate for organic pollutants degradation are increasingly recognized as an environmentally important sewage treatment technology. In this study, polyvinyl pyrrolidone (PVP) modified Fe3O4 loaded ZIF-67 magnetic catalyst with transition metal cobalt ion was prepared for the first time by microwave-assisted solvothermal (MS) method within 30 min to activate peroxymonosulfate. The microwave synthesis process changed the time-consuming shortcoming of conventional method. The catalytic activity of the synthesized Fe3O4-PVP@ZIF-67 was assessed on bisphenol F (BPF) removal. The result showed 99.8% BPF was removed under the conditions of catalyst content of 0.15 g·L−1, PMS content of 0.3 mM, and pH without adjustment in 60 min. And the Fe3O4-PVP@ZIF-67/PMS system exhibited a quality catalytic performance when the solution pH of BPF varied from 3 to 11. Compared with humic acid (HA), inorganic anions (Cl−, H2PO4−, SO42−, HCO3−, and CO32−) showed slight effect to the degradation system. The quenching experiment verified that the main active substance in this system was SO4−•. Based on the degradation intermediates identified by gas chromatography-mass spectrometer (GC–MS), the main degradation pathways were proposed for the degradation of BPF. Overall, Fe3O4-PVP@ZIF-67 as PMS activator is promising catalyst for sulfate radical-based wastewater treatment.

Optimal Selection of Sewage Treatment Technologies in Town Areas: A Coupled Multi-Criteria Decision-Making Model.

In recent years, the development of sewage treatment technologies has made many treatment options available in towns. Selecting the most appropriate alternative (MAA) can make the best use of existing resources to achieve the optimal effect, which has become a topical issue in academic circles. The Liao River basin in China is an important area for agricultural cultivation and animal husbandry, but it also suffers from water shortages and pollution. In this study, the fuzzy set theory (FST), the Analytic Hierarchy Process (AHP), and the Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) were combined as a scientific and effective multi-criteria decision-making (MCDM) model to optimize the sewage treatment technologies in town areas of the Liao River basin. It was found that compared with natural treatment technologies (such as constructed wetlands, stabilization ponds, etc.) and combination technologies (i.e., a combination of various technologies), single small-scale sewage treatment plant technologies (such as activated sludge process or sequencing batch reactor with small daily capacity) were more suitable for those areas. The indicator of construction costs was critical in this model, and the fluctuation of its weight might change the MAA. This study aims to provide a decision support framework for the future optimization of sewage treatment technologies in towns by combining economic, environmental, and social issues, rather than just focusing on the technical aspects.

Effect of the combination of wetland and sewage treatment technology on the treatment of domestic sewage in Zhejiang province

Sample from 25 A2O + horizontal flow constructed wetland (HFCWs) and 49 A2O + vertical flow constructed wetland (VFCWs) in Suzhou, Huzhou, and tested inflow and outflow (COD, NH3-N, TN, TP and SS), to evaluate the stability of the effluent and the rate of compliance. The effects of the two combined processes on the treatment of rural domestic sewage and their design and operation were compared and studied. The results show that the stable effluent compliance rate of A2O + VFCWs is higher than that of A2O + HFCWs. The effluent quality stability of A2O + VFCWs is better in winter, but worse in summer. The removal effect of the A2O unit in the two combined processes is not ideal, which may be related to the low carbon to nitrogen ratio of the influent and less sludge. Based on the above results, it is recommended that the county-level city proceed with upgrading and reconstruction in terms of structure and operation.

Assessment of the effectiveness of biological treatment wastewater at “Binokor” aeration station located at Urta Chirchik district of Tashkent region

The article summarizes the results of research on improved sewage treatment technology at the “Binokor” Aeration Station, the biological treatment technology of pistia and eichhornia aquatic plants; studies have shown that the physical and chemical composition of wastewater improved after 7 days of planting aquatic plants, that is, the smell of the water has disappeared, the color has become clearer, the pH of the water has been neutral, the nutrients were absorbed by plants from 50% to 70% of, and the demand for oxygen was satisfied to 95%. It should be noted that the pistia plant has a more active absorption of substances in the domestic wastewater than the eichhornia species.

In Vitro Cytotoxicity Study of Cyclophosphamide, Etoposide and Paclitaxel on Monocyte Macrophage Cell Line Raw 264.7.

The presence of antineoplastic compounds in aquatic ecosystem is an emerging challenge for the society. Antineoplastic compounds released into the aquatic environment exhibit a potential threat to normal aquatic life. Particularly, antineoplastic compounds are responsible for direct or indirect interference with the cellular DNA of an organism and cause toxicity to cells. The present study focused on the assessment of in vitro toxic effect of cyclophosphamide, etoposide and paclitaxel on Raw 264.7 cell line (mouse monocyte macrophage cells). The inhibitory concentration of cyclophosphamide, etoposide, and paclitaxel was determined. The IC50 values of these compounds were 145.44, 5.40, and 69.76µgml-1 respectively. This is the first report on toxicity analysis of cyclophosphamide, paclitaxel and etoposide on Raw 264.7 cell line by reducing cell viability and indicating the cell cytotoxicity i.e., 69.58% for cyclophosphamide, 92.01% for etoposide and 88.85% for paclitaxel on concentration 250µgml-1. The results of their cytotoxicity assessment highlight the need of improvement in sewage treatment technology for the efficient removal of these compounds from aquatic environment.

Advances in anaerobic membrane bioreactor technology for municipal wastewater treatment: A 2020 updated review

The application of anaerobic membrane bioreactors (AnMBR) for mainstream municipal sewage treatment is almost ready for full-scale implementation. However, some challenges still need to be addressed to make AnMBR technically and economically feasible. This article presents an updated review of five challenges that currently hinder the implementation of AnMBR technology for mainstream sewage treatment: (i) membrane fouling, (ii) process configuration, (iii) process temperature, (iv) sewage sulphate concentration, and (v) sewage low organics concentration. The gel layer appears to be the main responsible for membrane fouling and flux decline being molecules size and morphology critical properties for its formation. The review also discusses the advantages and disadvantages of five novel AnMBR configurations aiming to optimise fouling control. These include the integration of membrane technology with CSTR or upflow digesters, and the utilisation of scouring particles. Psychrophilic temperatures and high sulphate concentrations are two other limiting factors due to their impact on methane yields and membrane performance. Besides the methane dissolved in the effluent and the competition for organic matter between sulphate reducing bacteria and methanogens, the review examines the impact of temperature on microbial kinetics and community, and their combined effect on AnMBR performance. Finally, the review evaluates the possibility to pre-concentrate municipal sewage by forward osmosis. Sewage pre-concentration is an opportunity to reduce the volumetric flow rate and the dissolved methane losses. Overall, the resolution of these challenges requires a compromise solution considering membrane filtration, anaerobic digestion performance and economic feasibility.

Research on Water Treatment Technology of Low-energy Membrane Bioreactor Based on Computer Automation

Compared with traditional sewage treatment technology, it has the advantages of good effluent quality, high treatment efficiency, and automation. This article analyzed the mechanism of causing membrane fouling during its operation and proposed control strategies relying on computer automation technology, introduced several new membrane bioreactors and methods for process improvement, and finally looked forward to its future development trend.

Mitigation of diffuse CH4 and H2S emissions from the liquid phase of UASB-based sewage treatment plants: challenges, techniques, and perspectives.

Upflow anaerobic sludge blanket (UASB) reactors are considered to be a sustainable and well-established technology for sewage treatment in warm climate countries. However, gases dissolved in the effluent of these reactors, CH4 and H2S in some instances, are a major drawback. These dissolved gases can be emitted into the atmosphere downstream of the anaerobic reactors, resulting in odour nuisance and, in the case of H2S, corrosion, while in the case of CH4, increasing greenhouse gas emissions with a significant loss of potentially recoverable energy. In this sense, this study aims to provide a critical review of the recent efforts to control CH4 and H2S dissolved in UASB reactor effluents, with a focus on the different available techniques. Different desorption techniques have been tested for the removal/recovery of dissolved CH4 and H2S: diffused aeration, simplified desorption chamber, packed desorption chamber, closed downflow hanging sponge reactor, membrane contactor, and vacuum desorption chamber. Other recent publications addressing the oxidation of these compounds in biological posttreatments with simultaneous nitrification/denitrification of ammonia were also discussed. Additionally, the rationale of CH4 recovery was determined by energy balance and carbon footprint approaches, and the H2S removal was examined by modelling its emission and atmospheric dispersion.