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\"Proper engineering and execution of aeration control systems is of prime importance to treatment plants, representing a significant savings in labor and energy costs. Taking an integrated, cross-disciplinary approach to this critical process, Aeration Control System Design comprehensively addresses the concept and system design of aeration activated wastewater treatment. Covering complete treatment of aeration system controls, processes, and instrumentation, this hands-on text provides civil and environmental engineers, mechanical engineers, and electrical/instrumentation engineers with theoretical and mathematical treatment of case histories, complete with design procedures and analysis methodology\"-- Provided by publisher.

Currently, the pollution control situation of the sewage systems across Taiwan can be divided into the two major sewage systems, namely, industrial area sewage and public community sewage. When the counties and cities of Taiwan cannot effectively control the sewage pollution situation, ecological pollution of the environment and personal health damage would result. Therefore, evaluating the pollution control situation of the sewage systems can help the environmental protection authorities developing strategies for the pollution control of the sewage systems in the future. In this study, the Vise Kriterijumska Optimizacija I Kompromisno Resenje (VIKOR) method was applied to evaluate the pollution control situation of the sewage systems. The water sample test qualification rate, the emission permit issuance rate, and the staff setting rate of the dedicated wastewater treatment company were used as the pollution control evaluation indexes. According to the results, the use of the VIKOR method to evaluate the pollution control situation of the sewage systems is effective. In cities and counties in Taiwan, public community sewage systems, dedicated to pollution control case, the public community should be actively coached in emission control technology to upgrade sewage capacity, the issuance of discharge permits, and the staff setting rate of the dedicated wastewater treatment, to improve public community sewage pollution control system capabilities. In Taiwan, the industrial area sewage systems, dedicated to pollution control situations, must pay attention to business units in raw materials, spare part inventory, and machine supplier of choice, and we must choose to meet environmental supply chain of green suppliers, which would be effective in reducing effluent produce and improve water sample test qualification rate. The VIKOR value of Yilan County is 1.0000, which is the worst in the pollution control of all the industrial area sewage systems, followed by Taoyuan County (0.2253) and Kaohsiung City (0.1334). Other cities and counties of Taiwan have good performance in the pollution control of the industrial area sewage systems. The VIKOR value of Kinmen County is 1.0000, which is the worst pollution control among the all public community sewage systems, followed by Hsinchu County (0.7458) and New Taipei City (0.5527). Among the cities and counties with good pollution control of the public community sewage systems, the best is Chiayi County (0.0000), followed by Kaohsiung City (0.0159) and Hsinchu City (0.0352). Chiayi County is a good performance compromise between all VIKOR values (0.0000), whether in industrial or public community area pollution control sewage systems. Yilan County industrial pollution control has the poorest performance of all the industrial area sewage systems in Taiwan, but in the public community, it ranked as fourth place of all the public community area sewage systems in Taiwan. The VIKOR method proposed in this study can effectively evaluate the pollution control situation of the sewage systems, and serve as a reference for the environmental protection authorities in developing the strategies for the pollution control of the sewage systems.

Oilfield Sewage System Scheduling is a complicated, large-scale, nonlinear system problem with multiple variables. The complexity of the sewage system pipeline network connection grows along with the ongoing building of oilfield stations, and the shortcomings of the sewage system water quantity scheduling program based on human experience decision-making become increasingly apparent. The key to solving this problem is to realize the digital and intelligent scheduling of sewage systems. Taking the sewage system of an oil production plant in Daqing oilfield as the research object, the water scheduling model of the sewage system is established in this paper. Aiming at the complex nonlinear characteristics of the model, the Levy flight speed updating operator, the adaptive stochastic offset operator, and the Brownian motion selection optimization operator are established by taking advantage of the particle swarm optimization (PSO) and the cuckoo search (CS) algorithm. Based on these operators, a hybrid PSO-CS algorithm is proposed, which jumps out of the local optimum and has a strong global search capability. Comparing PSO-CS with other algorithms on the CEC2022 test set, it was found that the PSO-CS algorithm ranked first in all 12 test functions, proving the excellent solving performance of the PSO-CS algorithm. Finally, the PSO-CS is applied to solve a water scheduling model for the sewage system of an oil production plant in Daqing Oilfield. It is found that the scheduling plan optimized by PSO-CS has a 100% water supply rate to the downstream water injection station, and the total energy consumption of the scheduling plan on the same day is reduced from 879.95 × 106 m5/d to 712.84 × 106 m5/d, which is a 19% reduction in energy consumption. The number of water balance stations in the sewage station increased by 7, which effectively improved the water resource utilization rate of the sewage station.

Extraneous water that inflow to the sewage system is basically divided into two streams—accidental water (mainly rainwater) and infiltration water. The aim of the research was to assess the amount of extraneous water inflow to the considered system. Five different quantitative approaches were applied. Three well-known methods were used: the triangle method, the minimum night flow method, and the moving minimum method. The annual balance of water consumption and sewage supply to the wastewater treatment plant were calculated. Also, some analysis of sewage discharge during wet and dry weather was carried out. The study covered data from 6 years from 2014 to 2019. It was established that the main source of extraneous water was infiltration, because three methods which concern both streams (triangle method, minimum night flow, variability in wet and dry weather) confirm the conclusion. Merely the moving minimum method results differ from the others. In this investigation, accidental water (basically rainwater inflow) poses a significantly less share in the total volume of sewage compared to infiltration water. The total amount of extraneous water was estimated as in the range from 38 to 53% of annual sewage supply to wastewater treatment plant, depending on the year. Share of infiltration and accidental water is changing in different methods. Share of infiltration was in a range between 18 and 68%, depending on the year and the method used. Share of accidental water was in a range between 7 and 22%.

Ecosystem services in urban areas have deteriorated year on year due to increased urbanization. As a consequence of increased urbanization, floods threaten inhabitants of various cities in Japan. Although a conventional way of treating urban flooding is to construct sewage systems, alternative approaches have to be developed because of their expense in the context of the current financial crisis, especially in local governments. Rain gardens, a type of low-impact development, have recently been recommended as a best management practice for the treatment of stormwater runoff in Northern European countries, the USA, etc. While demand for rain gardens has been increasing in Japan, there is a lack of knowledge about their functions and characteristics. The present study aims to explain the function of rain gardens through a verification experiment and field survey. This study shows that rain gardens are suitable for dealing with low flow volumes of rainwater, although their suitability could be slightly changed by soil properties and catchment area. Our field survey indicated that rain gardens must be connected to a sewage system. In addition, like other green infrastructure, rain gardens require maintenance. The most frequent type of maintenance is the disposal of garbage, as garbage can block channels running between a rain garden and a conventional sewage system. Moreover, garbage build up can lead to the retention of rain water for more than 36 h, and this water can become a habitat for mosquito larvae.

Flooding of the sewage system is an environmental hazard often caused by illegal connections between drainage and sewage systems. The timely detection of such illicit connections, often done by property owners in an attempt to remove rainwater promptly from their private courtyards, is a complex task due to the high cost of field surveying and limited manpower of environmental law-enforcement authorities. This paper suggests an empirical approach to the identification and characterization of localities with an elevated likelihood of illegal connections between runoff and sewage systems. The proposed approach is implemented in three stages. First, the association between rainfall and the amount of wastewater arriving to sewage treatment facilities from different localities is analyzed. Next, regression residuals are investigated, to identify localities with an especially strong association between the amount of rainfall and sewage surplus. The identified localities are then analyzed, to determine their geographic location, physical and socioeconomic attributes. In the present study, the proposed approach is tested using data for 623 urban and rural localities in Israel. As the study shows, the probability of association between the amount of rainfall and sewage surplus, which we consider as an indicator of pirate connections between drainage and sewage systems, tends to increase as a function of socioeconomic welfare of the local residents, surface slope, and the level of urbanization. The proposed approach can help law-enforcement authorities to focus their efforts on specific locations and to reduce economic and environmental damages associated with illegal connections between drainage and sewage systems.

Kigali city, the capital of Rwanda, relies on decentralized, on-site, wastewater systems due to the absence of central sewerage systems and the limited finances to construct sustainable sanitation infrastructures. However, the city has increasingly shown failures in managing these on-site systems either at individual or collective levels. This study aims at assessing the sustainability of the operated collective public semicentralized sewage systems in Kigali city. To fully cover the sustainability assessment of such collective systems, the methods used were field observation, questionnaires, interviews, and laboratory tests. The study also reviewed the influence of national ruling sanitation legal instruments in addressing development, operation and management of such decentralized wastewater systems. The results showed that the sustainability levels of these systems were low in the technical, socioeconomic status, institutional, and legal dimensions. While the sustainability level was fair for the environmental quality. In conclusion, the research highlighted that the improved sanitation coverage does not mean coverage in terms of sewerage connection proportions for wastewater collection as these connections do not imply safe and sustainable treatment before being discharged into the environment.

The sulfuric acid permeation and biofilm formation behaviors of polysiloxane films have been investigated, and simple methods for evaluating the sulfuric acid permeation and biofilm formation behaviors have been proposed in this paper. The polysiloxane films used in these experiments were practically impermeable to the aqueous sulfuric acid solution, and the amount of biofilm formation varied depending on the composition of the films. Further, the amount of sulfuric acid permeation can be estimated by measuring the polarization curves of polysiloxane films with different thicknesses formed on iron electrodes. By measuring the adhesion work of pure water and simulated biofilm droplets on polysiloxane films of different compositions, we can estimate the resistance of biofilm formation on the polysiloxane films.

The study provides a comparative analysis of the quality of sewage discharged from selected sewerage systems. The analyzed data were collected from 10 agglomeration sewerage systems discharging sewage into collective wastewater treatment plants (WTP). The investigated pollution indicators included BOD , COD , total suspended solids and biogenic indicators such as total nitrogen and total phosphorus. These results were compared with the outcomes reported in commonly available research papers on sewage disposal. Considering the concentration of individual pollution indicators, more detailed categories of sewage pollution were adopted in this work. The sewage was divided into five basic groups: I – highly concentrated, II – concentrated, III – moderately concentrated, IV – diluted, and V – highly diluted. The sewage categories accounted for the following pollution indicators: BOD , COD , total suspended solids, total phosphorus and total nitrogen. Mean BOD , COD and total suspended solids in raw sewage were higher than average values reported in the referenced literature. Contrary to that, concentration of total phosphorus in raw sewage was significantly lower than reported by other authors. The outcomes of this study suggest that the predictions concerning pollution degree of raw sewage made at WTP design stage should not be based exclusively on general values provided in literature reports.

Due to the high underground water level, frequent rainfall, and large amounts of infiltration and inflow (I/I) into the sewage system, a city in the plain river network region had to face a series of problems caused by the high water-level operation of the drainage system. Suzhou, a city in the Yangtze River Delta region of China, can be a representative of cities in plain river networks, where this research was carried out. The amount of I/I into the sewage system was evaluated, and the storm water management model (SWMM) was used to further calculate the sewer water storage capacity under dry and wet weather with multi-year average rainfall. Based on the offline model calculation and artificial experiences, the rule-based online regulation and storage real-time control strategy (RTC) is verified, and the online regulation and storage intelligent scheduling demonstration is carried out in the central-city district of Suzhou. The results showed that the infiltration in dry weather accounted for about 20–25% of the total collected wastewater; in wet weather (36 mm precipitation), the extraneous water induced by I/I peaked at 73.64%. The collaborative control of regional multi-stage pumping stations through RTC of the sewage system can effectively avoid the high water-level operation caused by peak sewage flows on dry days. In combination with rainfall forecasting, the coordinated control of plants and pumping stations to pre-empty the sewer pipelines prior to rainfall can, to some extent (up to 35 mm of rainfall in this study), cope with the increase in I/I induced by rainfall.