Factor Analysis on Quantity of Discharged Pollutants in Wastewater in Major Cities

The research performed statistical analysis on 186 data concerning the amount of discharged industrial wastewater, the amount of oxygen demand of industrial wastewater, the amount of ammonia and nitrogen discharged from industries, the amount of urban discharged domestic sewage, the amount of daily life chemical oxygen demand, and the amount of domestic ammonia and nitrogen to explore source of pollutants from wastewater and guarantee urban water quality.Factor analysis was then performed with SPSS according to discharge quantity of pollutants. The results should that the major pollutants are from domestic sewage it is expected scientific suggestions be proposed on water quality in our country.

Performance of a Horizontal Flow Constructed Reed Bed Filter for Municipal Wastewater Treatment: The Case Study of the Prototype Installed at Gaston Berger University, Saint-Louis, Senegal

In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed only a slight temperature variation, from an influent average of 26.3°C to an effluent of 24.7°C. Electrical conductivity decreased from 1331 mS/cm to 974.5 mS/cm post-primary treatment, with suspended solids (SS) dramatically reduced from 718.9 mg/L to 5.7 mg/L in the final effluent. Biochemical oxygen demand (BOD5) and chemical oxygen demand (COD) saw a notable decrease, from initial levels of 655.6 mg/L and 1240 mg/L to 2.3 mg/L and 71.3 mg/L, respectively. Nitrogenous compounds (N-TN) and phosphates () also decreased significantly, indicating the system’s nutrient removal capacity. Microbiological analysis revealed a reduction in fecal coliforms from 7.5 Ulog/100ml to 1.8 Ulog/100ml and a complete elimination of helminth eggs. The presence of Phragmites and Typha was instrumental in enhancing these reductions. The system’s compliance with the Senegalese standards for disposal into natural environments, WHO recommendations for unrestricted water reuse in irrigation, and the European legislation for water reuse was established. The effluent quality met the stringent criteria for various classes of agricultural reuse, illustrating the system’s potential for sustainable water management. This wetland model presents a robust solution for water-stressed regions, ensuring environmental protection while supporting agricultural needs. The study calls for ongoing research to further refine the system for optimal, reliable wastewater treatment and water resource sustainability.

Monitoring of Atmospheric Pollutant Concentrations in the City of Dakar, Senegal

The lack of data on air quality monitoring and neglected and overlooked pollutant emissions in the transportation and industrial sectors are motives for the government of Senegal to set up, in 2009, an air quality management center, the CGQA (Centre de Gestion de la Qualité de l’Air). Air quality monitoring at CGQA deals with mainly six pollutants: carbon monoxide (CO), nitrogen oxides (NOx) (with nitrogen dioxide (NO2) and nitrogen monoxide (NO)), sulfur dioxide (SO2), ground-level ozone (O3), Benzene-Toluene-Xylenes (BTX), and particulate matters (PM) with diameters less than 10 μm (PM10) and 2.5 μm (PM2.5). The concentration levels of gaseous pollutants (CO, O3, NO2 and SO2) in the city generally remain below the limit value set by the WHO (World Health Organization). However, particulate matters (PM10 and PM2.5) are the most important pollutants observed in Dakar, they far exceed the annual thresholds set by the WHO and the national standard (NS 05-062). This situation results in an Air Quality Index (AQI) around bad and very bad during the dry season (November to May) and good to moderate during the rainy season (June to October). The concentrations of PM10 and PM2.5 vary respectively from 120 to 180 μg·m-3 and from 25 to 48 μg·m-3. The average concentrations of pollutants therefore vary from one area to another and depending on the location of the air quality monitoring station (near industrial sites, traffic, etc.).

Mixing Zone Guidelines Application in a Smelter in Northern Sweden with Discharge to the Baltic Sea

This pilot study intended to investigate the application of Mixing Zone Guidelines in northern Sweden. The EC （European Commission）-Mixing Zone Guidelines were applied to seven effluent discharges. The effluents were from industrial processes used in the Ronnskar smelter, in northern Sweden. Each outlet in the smelter area discharges water into the Bothnian bay of the Baltic Sea. Cadmium （Cd）, mercury （Hg）, nickel （Ni） and lead （Pb） were the primary substances present in the effluents. A ＂Tiered Approach＂ was followed for mixing zone assessments in each of the discharge points. Discharge Test was used at Tier 2 and CORMIX （Cornell Mixing Zone Expert System model）, version 7, at Tier 3. At each discharge point, the AA-EQS （annual average-environmental quality standard） for each metal was met within a distance of 500 m from the outfalls. This distance was exceeded to meet the MAC-EQS （maximum allowable concentration-environmental quality standard） criteria at points 1 and 3 for total Hg concentrations. However, for the proper application of Mixing Zone Guidelines, a version of the Discharge Test for coastal waters should be developed and used. The decision at which tier the dissolved metal concentration should be compared with EQS values could depend on the effluent characteristics. For Swedish coastal waters, some consideration should be given to the background concentration of metals.

Principal Component Analysis of Major Pollutants Discharge Amount in Major Cities

With the development of industry in China, the emission issues of indus- trial wastewater has got more and more attention. Excessive levels of pollutants in wastewater are urgent problem to be solved. Together with the emissions of do- mestic wastewater, the discharge amount of pollutants has exceeded standard in many cities, which not only pollutes the water resources, but also greatly threatens the environment, and does great harm to people＇s health. The principal component analysis was conducted based on the principal components extracted from the data of major pollutants emission conditions in the wastewater of major cities from the China Statistical Yearbook 2014.

Rapid detection to long ship wake in synthetic aperture radar satellite imagery

The maritime administrative department employs synthetic aperture radar (SAR) satellite remote sensing technology to obtain evidence of illegal discharge of ships. If the ship is discharged during navigation, it forms a long dark wake on the SAR image due to the suppression of the Bragg wave by the oil fi lm. This study investigates key techniques for rapid detection of long ship wakes, thereby providing law enforcement agencies with candidate ships for possible discharge. This paper presents a rapid long ship wake detection method that uses satellite imaging parameters and the axial direction of the ship in images to determine the potential detection area of the wake. Then, the threshold of long ship wake detection is determined using statistical analysis, the area is binarized, and isolated points are removed using a morphological filter operator. The method was tested with ENVISAT Synthetic Aperture Radar and GF-3 SAR data, and results showed that the method was eff ective, and the overall accuracy of the decision reaches 71%. We present two innovations;one is a method that draws a Doppler shift curve, and uses the SAR imaging parameters to determine the detection area of the long wake to achieve rapid detection and reduce the image detection area. The other is where a classical linear fitting method is used to quickly and accurately determine whether the detected dark area is a long ship wake and realizes the twisted long ship wake detection caused by the sea surface flow field, which is otherwise diffi cult to detect by the traditional Radon and Hough transform methods. This method has good suppression performance for the dark spot false alarm formed by low speed wind region or upward flow. The method is developed for maritime ship monitoring system and will promote the operational application of maritime ship monitoring system.

Numerical simulation of the transport and diffusion of dissolved pollutants in the Changjiang (Yangtze) River estuary

Based on a coupled hydrodynamic–ecological model for regional and shelf seas (COHERENS), a three-dimensional baroclinic model for the Changjiang (Yangtze) River estuary and the adjacent sea area was established using the sigma-coordinate in the vertical direction and spherical coordinate in the horizontal direction. In the study, changing-grid technology and the "dry-wet" method were designed to deal with the moving boundary. The minimum water depth limit condition was introduced for numerical simulation stability and to avoid producing negative depths in the shallow water areas. Using the Eulerian transport approaches included in COHERENS for the advection and dispersion of dissolved pollutants, numerical simulation of dissolved pollutant transport and diffusion in the Changjiang River estuary were carried out. The mass centre track of dissolved pollutants released from outlets in the south branch of the Changjiang River estuary water course has the characteristic of reverse current motion in the inner water course and clockwise motion offshore. In the transition area, water transport is a combination of the two types of motion. In a sewage-discharge numerical experiment, it is found that there are mainly two kinds of pollution distribution forms: one is a single nuclear structure and the other is a double nuclear (dinuclear) structure in the turbid zone of the Changjiang River estuary. The rate of expansion of the dissolved pollutant distribution decreased gradually. The results of the numerical experiment indicate that the maximum turbid zone of the Changjiang River estuary is also the zone enriched with pollutants. Backward pollutant flow occurs in the north branch of the estuary, which is similar to the backward salt water flow, and the backward flow of pollutants released upstream is more obvious.

The Impact of Urban Flooding on Surface Water Quality of Awka Town

Some physico-chemical and bacteriological parameters were analyzed for in the water samples of four different ponds located in Awka town both prior and after the rain to ascertain the impact of flood in these ponds and to establish whether the pollution was significant. Four samples were collected from each pond both before the rain and after making it a total of thirty-two samples. Twenty-seven parameters were analyzed for in each of the samples. The result revealed that twelve parameters exceeded WHO standard before the rain while fourteen exceeded after the rain. There was significant increment in the values of the analyzed parameters after the rain when compared with the value before the rain as revealed by the Anova statistical tool. It was discovered that there was a major increase in the bacteriological parameters after the rain which implied the serious health impact. It was recommended that users who utilized these ponds for squeezing bitter leaf, processing cassava and washing meats etc. should do so with the caution so as not to expose people to health problems.

Discharge water temperature assessment of thermal power plantusing remote sensing techniques

Thermal power plants are generally constructed near to sea coast to meet their requirement of coolingwater. The warm water discharge from the thermal power plant is one of the major environmentalconcerns in view of the thermal pollution in the sea water. The temperature limit for the warm waterdischarge from the thermal power plant has to be monitored and controlled. Coastal Gujarat PowerLimited (CGPL) operates (24×7) at an “once-through system” based sea water circulation for powergeneration. The used sea water is then discharged into the sea through an outlet channel. As per environmental norms, the discharge water temperature needs to be maintained below the stipulated “delta”rise (+7 ℃) with respect to ambient sea surface temperature at the inlet. We demonstrate the applicability of thermal remote sensing data in understanding the seasonal and temporal variations of thetemperature difference between the discharge water and the ambient sea water. We used thermal banddata from Landsat-8 satellite imagery to map water surface temperature and create temperature profilesalong the intake and outflow channels (till the sea), to understand the variation of temperature andestimate the “DT” between intake point and various observation points along the outflow. This analysiswas carried out for all 11 months (except June) of the year 2018 to correlate temperature variations withseasonal changes. Tidal conditions during the time of data acquisition were also considered to accountfor the effect of tides on DT. The result shows that the average temperature rise between intake andoutflow are maintained at ~3 ℃ across all the months of 2018, with minor variations in the months ofJuly and August. Further, average temperature drop from outflow to cooling channel (before diaphragm)is seen to be ~2 ℃ across all the months with similar seasonal fluctuations.

Influence on the Ground and Air and Mathematical Description of the High-Voltage Discharge

According to trends of the development the high-voltage devices’ usage and unpredictable weather causes,we find it very important to research electrical discharge from different sources.In our opinion,the most important is to analyze an influence of the atmospheric electricity on the air and ground, create an exact mathematical model of the physical processes,and describe the ecological influence.

Preparation of calibration standard of organic vapours using the diffusion tube method

This paper describe the theoretical consideration, experimental results and applications of diffusion tube, used for preparing the calibration standard of organic vapours. This dynamic procedure entirely eliminates the adsorption effect, which is important in static procedures. Its concentration range is wider than that of the permeation tube. The diffusion tube technique is therefore a very accurate, simple and easy-to-make device. It is quite useful in the determination of organic pollutants existing in the environment.

Water Quality from the Purification Unit of Thiakhar (Diourbel, Senegal) and Impact of Discharges from Treatment on Water Resources

The installation of a purification unit since 2008 in the village of Thiakhar has improved the physico-chemical and bacteriological quality of the water supply. However about 55% of the raw water comes out of the unit as discharges (approximately 14 m3 per day) highly concentrated in fluoride and chloride ions. Based on historical samples, we find that the volumes of water consumed together with the volumes of water discharged are increasingly significant from year to year. The storage of waste water is carried out in a septic tank connected to a leaking cesspool sink. Significant excesses of these discharges are visible on the site and a flow of concentrate is observed creating a puddle of water that attracts birds and straying cattle. The study describes the following substantial impacts on the natural and human environment: 1) contamination of groundwater, 2) soil salinization 3), impact on flora and fauna, 4) impact on health. The study concludes by identifying measures to mitigate the negative impacts related to the discharges and by proposing alternative solution.

Implementation of the Air Quality Monitoring Network at Agadir City in Morocco

Air pollution is a major global issue with widely known harmful effects on human health and the environment. This pollution is a very complex phenomenon given the diversity of pollutants that may be present in the atmosphere. The air quality in urban areas is of a great concern for residents living in cities and represents a current issue that requires an adequate management. So that air quality policy is driven by health concerns. In this paper, we present an overview on the experience of Agadir city to establish the air quality management policy, local authority on the whole have developed a good understanding of air quality in the area. Indeed for several years, efforts have been made to monitor the air quality in this city, this translated by air quality assessment since 2006 using mobile laboratory and fixed station. Our goals in this study were to review the operation of Local Air Quality Management (LAQM) making better use of available resources to improve its outcomes and make recommendations with a view to improving air quality issues. This work highlights the requirement to revise periodically the LAQM for generating priority for air quality issues within local authority and the need to implement the optimizing Air Quality Monitoring Network (AQMN).

Influence of Rainfall, Discharge, Wave and Alongshore Transport on Microbiological Pollution in Southern California Coastal Beaches

The coastal zone is the significant environmental setting where ocean interfaces land. In addition, it is economically important because of its high residential, commercial and recreational values. Meanwhile, in the United States, public coastal areas are increasingly off-limits due to elevated levels of fecal pollution and other contaminants. This study investigates the effects of rainfall, discharge, wave, and alongshore transport on coastal FIB （fecal indicator bacteria） concentrations at adjacent beaches in Orange County, California, over three years＇ period from October 2001 to September 2004. In order to identify the dominant tempora land spatial patterns of fecal pollutions along the coastal beaches, Empirical Orthogonal Function analysis was utilized for the three-year measurements （n = 39,525） of FIB concentration data from 17 sampling stations. Through the data analysis and the empirical orthogonal function analysis, it was found that the dominant factor effecting coastal FIB concentration is precipitation event and consequent water discharge from Santa Ana River in the area. The Empirical Orthogonal Function analysis revealed the potential non-point FIB sources around northern part of Orange County beaches. In addition, this study confirmed the existing alongshore transport by wave-driven surf zone current and offshore tidal currents.

Effective Removal of Air Pollutions by the Electrical Discharge

The objectives of this study were to understand the effects of different electrical and reactor＇s parameters on the removal efficiency of air pollution and to optimize the parameters to achieve the highest removal efficiency. The surface discharge was applied to dielectric barrier discharge reactors and the voltage, current, frequency and the electrode shape were employed to the reactor as main variables. In general, it has been known that the removal efficiency is decided by the applied power, which is calculated by multiplication of the applied voltage and current. However, the removal efficiency was significantly changed by the composition ratio of the applied voltage and current even though the experimental conditions were not changed with the same applied power. It means that the removal effectiveness should be affected not by the discharge power but by the applied voltage and current separately. From the experimental and statistical analysis, the discharge current was the most important factor to control the removal efficiency regardless of different types of the reactors and the frequency is not the direct function to control the removal rate.

Spatiotemporal characteristics of cultivated land use eco-efficiency and its influencing factors in China from 2000 to 2020

Improving cultivated land use eco-efficiency(CLUE)can effectively promote agricultural sustainability,particularly in developing countries where CLUE is generally low.This study used provincial-level data from China to evaluate the spatiotemporal evolution of CLUE from 2000 to 2020 and identified the influencing factors of CLUE by using a panel Tobit model.In addition,given the undesirable outputs of agricultural production,we incorporated carbon emissions and nonpoint source pollution into the global benchmark-undesirable output-super efficiency-slacks-based measure(GB-US-SBM)model,which combines global benchmark technology,undesirable output,super efficiency,and slacks-based measure.The results indicated that there was an upward trend in CLUE in China from 2000 to 2020,with an increase rate of 2.62%.The temporal evolution of CLUE in China could be classified into three distinct stages:a period of fluctuating decrease(2000-2007),a phase of gradual increase(2008-2014),and a period of rapid growth(2015-2020).The major grain-producing areas(MPAs)had a lower CLUE than their counterparts,namely,non-major grain-production areas(non-MPAs).The spatial agglomeration effect followed a northeast-southwest strip distribution;and the movement path of barycentre revealed a"P"shape,with Luoyang City,Henan Province,as the centre.In terms of influencing factors of CLUE,investment in science and technology played the most vital role in improving CLUE,while irrigation index had the most negative effect.It should be noted that these two influencing factors had different impacts on MPAs and non-MPAs.Therefore,relevant departments should formulate policies to enhance the level of science and technology,improve irrigation condition,and promote sustainable utilization of cultivated land.

On Environmental Quality Standards and Finding of Liability for Environmental Pollution Torts

Though bearing technical and legal attributes,environmental quality standards are neither rules nor regulatory documents.With the binding force coming from the legal norms where they are cited,environmental quality standards are designed and implemented as a yardstick for measuring environmental quality.They also play a role in the functions of goal setting,merit appraisals,inspiration,supervision and accountability in conjunction with the legal norms and administrative plans where they are cited.Characteristically,environmental quality standards adopt sort management in concept,take holistic values and methodologies,establish phased goals and accept the resulting policy choices.These standards are not applicable to determine tort liability caused by environmental pollution from the perspective of legal norms but provide limited evidence for finding the same in the view of factual analysis by delivering scientific support to prove negative effects on the environment.Hence,environmental quality standards do contribute to finding torts,thus making the production of evidence less difficult.Also,they can be used to prove the relevance between torts and damage.

Generation and Discharge of Pollutants in Closed Aquaculture

[Objectives]To gain an in-depth understanding of pollutant generation and discharge from closed aquaculture.[Methods]In 2018,the pollutant generation and discharge coefficients of 7 farming modes in 16 farming bases were calculated and analyzed.[Results]A total of 28 pollutant generation coefficients and 28 pollutant discharge coefficients were obtained,and the generation and discharge of pollutants in closed aquaculture were grasped preliminarily.Compared with the data of the first census of pollutions sources published by the state in 2008,7 kinds of pollution generation coefficients increased,while 14 kinds decreased;and 4 kinds of pollutant discharge coefficients increased,while 17 kinds decreased.[Conclusions]In recent years,the pollutant generation and discharge coefficients of aquaculture show a decreasing trend.

Suitability of Groundwater from the Kherzet Youcef Lead-Zinc Deposit (North-Eastern Algeria) for Irrigation and Drinking Water Supply

As part of the hydro geological study of the Kherzet Youcef deposit, a drilling battery was carried out. The objective of this achievement is the satisfaction of the water needs of the city of Ain Azel (drinking water supply, irrigation and industrial water supply) and even the transfer to other municipalities suffering by the lack of water and the resumption of mining activity at the deposit of Kherzet Youcef. This water table is located in carbonate formations of Paleo-Neogene age linked to lead-zinc mineralization. Knowledge of water quality and its suitability for human consumption is an obligation. These metals have adverse health effects. We used the results of Sonarem’s analyses from 1973 to 1979. In addition, we carried out two analyses, during two years 2015-2016, on five boreholes. The parameters analyzed are major elements, physical parameters and trace metal elements (Zn, Pb and Fe). The analyses were done by ICP-AES. In our work, it has been shown that waste water is suitable for use in agriculture. For this we used the electrical conductivity at 25°C and those of the sodium adsorption ratio (SAR). For drinking water supply, monitoring the change in trace metal element (Zn, Pb and Fe) for two years has allowed us to conclude that groundwater in the groundwater table east of the Kherzet Youcef fault is generally acceptable. They are eligible by the quality standard set by Algerian regulations. However, they exceed the world health organization (WHO) standards, especially for lead. We recommend a revision of drinking water quality standards set by Algerian regulations, rigorous monitoring of TME content variation and water treatment before distribution.

Evaluation of Effluent Discharge from Steel Manufacturing Industries on the Proliferating Environmental Degradation in Nairobi Metropolitan in the Republic of Kenya

The overall objective of this study was to establish the effects of steel industrial effluent on Nairobi metropolitan water system and its impact to the society. The study sought to identify various types of wastes produced by factories, assess how the waste generated is managed and disposed, examine the effects of effluent discharge on Nairobi River and finally propose mitigation measures. The research adopted a qualitative design and employed a number of methods: direct observations, document reviews to content analysis of the past studies, which in the end generated invaluable data. The study revealed that there are four categories of waste generated: solid waste, liquid waste, footbath chemicals as well as thermal wastes. It was also found that waste management in place was not effective enough leading to water and soil pollution. Other causes of pollution were found out to emanate from gasses contamination to the air and chemicals used during steel processing. The findings will inform the community of the harmful effects of untreated water and how it impacts on their health and productivity. It will also help the stakeholders in the environmental conservation to articulate issues of policy and influence agenda setting in the national and sub-national levels.