City Sewage Treatment Plant Research Articles

Evaluation of effluent post-treatment by slow filtration and adsorption with activated carbon produced from spent coffee grounds in surfactant removal in sewage treatment

Environmental pollution is a worldwide concern, especially when caused by sewage dumping into water bodies. Many substances are present in industrial or domestic wastewater, causing contamination in superficial water collection. Surfactants stand out for being widely used both industrially and domestically. The use of detergents and many types of surfactants was increased during the Covid-19 pandemic period, a fact observed in the levels in the effluent sample analysis from a Sewage Treatment Plant (STP) - Vila City around 21 and 39 mg L-1 in this period. This work evaluated the surfactant concentrations in the primary and secondary treatment units of the Vila City STP, in the city of Paranavaí-PR.-Brazil. In addition, the use of a post-treatment by slow sand filtration and adsorption by activated carbon produced from spent coffee grounds in the complementary removal of surfactants was proposed. A mixed bed with sand and activated carbon columns was made on a pilot scale, and filtration/adsorption runs were performed simulating slow filtration with rates of approximately 15 m3 m-2 day-1. The parameters used for the efficiency removal evaluation in a pilot plant run were: turbidity (NTU) and surfactant concentrations. The removal of surfactant concentrations was about 9% and 7% in the Upflow Anaerobic Sludge Bed reactors (UASB-RALF) and in the secondary treatment, respectively, at the STP – Vila City units. In the post-treatment proposed by filtration/adsorption, bed columns on a pilot scale plant obtained a reduction of approximately 94% in terms of turbidity (NTU) and 95% in terms of surfactant removal.
 Keywords: activated carbono, coffee poder, effluent, surfactants.

The Application Direction of Sludge Disposal Technology in City Sewage Treatment Plant

The Application Direction of Sludge Disposal Technology in City Sewage Treatment Plant

Occurrence, seasonal variation, mass loading and fate of pharmaceuticals and personal care products (PPCPs) in sewage treatment plants in cities of upper Ganges bank, India

The data on the environmental concentration of pharmaceuticals and personal care products (PPCPs) is hardly investigated for major cities of the upper Ganges basin, India. In this study, fifteen PPCPs were analyzed in four sewage treatment plants (STPs) of Haridwar and Rishikesh cities located at the bank of River Ganges, India. Eleven PPCPs were detected with an average total concentration of 147.20 ng L−1 in influent, 105.06 ng L−1 in the effluent, and 87.75 ng kg−1 in sludge from STPs. The average concentration (ng L−1) of individual PPCPs was recorded highest for Caffeine (695.86) followed by, ibuprofen (387.53), acetaminophen (152.81), triclosan (98.93), tetracycline (75.39), ketoprofen (69.47), DEET (46.59), salicylic acid (45.02), erythromycin (32.98), ciprofloxacin (20.16) and metoprolol (13.61) at STPs inlets. Results suggested a spatial and seasonal variation in PPCPs loads in influent, effluent and sludge in STPs studied. The overall PPCPs removal efficiencies of STPs were recorded in the ranges of −154–63%. The total mass load of PPCPs studied ranged between 0.02 and 448.64 mg/d/1000 population. This study concluded that STPs are an active source of PPCPs in the River Ganges, which may pose a grave threat to the health of the river ecosystem and human population.

Spatial and Seasonal Assessment of Water Quality in the Lobo Stream River Basin, Brazil Using Multivariate Statistical Techniques.

In view of the complexity of the processes associated to water quality, this study objective is to identify the main factors related to spatial and seasonal variability in water courses of the Lobo Stream River Basin. To this, multivariate statistical techniques were used. Data collection for water quality and streamflow variables were carried out monthly, from May 2018 to April 2019, at 10 monitoring points along basin's tributaries. The results show that, during the dry season, the main causes for water quality decrease are related to erosion process on the river margins, which is intensified by inadequate handling in livestock activities in some monitoring points. In the rainy season, the main causes are related to soil leaching in agricultural areas that increases the nitrogen compounds concentration and reduces water quality. However, in addition to this, it was noted that regardless the environmental conditions, the most impactful factor is the point pollution from the effluent discharge of Itirapina City sewage treatment plant, responsible for nutrient concentration increase, organic contamination, OD reduction, and, consequently, water quality deterioration. With this, the study shows how multivariate statistical analysis enables more relevant evaluation of water quality data variability and supports further studies in the basin.

G시 하수처리장의 미세플라스틱 함유량 특성과 배출량 추정

G시 하수처리장의 미세플라스틱 함유량 특성과 배출량 추정

Distribution and Source Analysis of Nitrate in Surface Waters of China

The nitrate pollution of surface water has attracted worldwide attention, and it is not optimistic in China. To identify the distribution, sources, and transformation mechanisms of nitrate in China's surface waters, the nitrate data of 71 major rivers from 7 regions were systematically collected. The spatial distribution of nitrate concentrations in surface water was analyzed, and the main nitrate pollution sources were revealed based on nitrogen and oxygen isotopes of nitrate. The results show that approximately 7.83% of rivers in China exceeded the Chinese drinking water standard for nitrate (45 mg·L-1). The concentrations of nitrate in Mudanjiang, Haihe River, and the estuary of Yangtze River was even more than 90 mg·L-1, which indicates a serious pollution phenomenon. The isotopic compositions of surface water in China ranged from -23.5‰ to 26.99‰ for δ15N-NO3 and from -12.7‰ to 83.5‰ for δ18O-NO3. The main sources of nitrate are domestic sewage in Northeast, Central, and East China, while those are inorganic fertilizers and domestic sewage in Southwest and South China. The nitrate sources of surface water in Northwest and North China are complex, mainly from domestic sewage, inorganic fertilizer, and nitration of soil organic matter. Through correlation analysis, it is found that the nitrate concentrations of surface water have a positive relationship with population, wastewater discharge, agricultural nitrogen fertilizer application, and GDP per capita in China. It is urgent to solve the problem of pollution and prevent the further pollution of China's surface waters. The new "10-Point Water Plan" issued by the Chinese government solved the previous problems, but it will take decades to control and repair the polluted surface waters. In Northwest, North China, Southwest, and South China, not only the scale of sewage treatment plants in cities and counties should be increased but also the use of agricultural fertilizers should be controlled and managed by the government. Northeast, Central, and East China need to further control point source pollution and reduce the discharge of industrial wastewater and domestic sewage into rivers.

Evaluation of the Performance Efficiency of Al-Najaf City Sewage Treatment Plant

Evaluation of the Performance Efficiency of Al-Najaf City Sewage Treatment Plant

溧阳重点流域污染源解析研究

流域源解析可为水环境综合整治提供依据。本文采用调查和数学模型估算溧阳重点流域内点源和面源的典型水污染物的排放量和贡献率。结果显示，渔业养殖、种植农村生活污水和污水厂是溧阳主要的水污染源。工业排放的污染物虽然贡献率较小，但是从2011到2013有逐年增加的趋势。种植业的总氮、总磷排放量分别占溧阳排放总量的46.24%和46.88%。渔业养殖排放的COD、总磷分别占溧阳排放总量的26.01%和40.83%，且排放贡献率有增加的趋势。点污染源排放的COD、氨氮、总氮、总磷的贡献率分别为37.12%，44.02%，21.30%和7.63%，而面源的相应污染物的贡献率分别为62.88%，55.98%，78.70%和92.37%。对面源的管理控制措施是溧阳水环境整治的重点。 Source apportionment can provide the basis for comprehensive improvement of water environment. Based on the investigation and mathematical model, this paper estimated water pollutants emission and contribution from point source and non-point source in the key rivers of Liyang city. The results show that: the fishery, rural domestic sewage and city sewage treatment plant are the main water pollutant sources. The contribution of water pollutants from industrial emission source is small and the water pollutants emission from is increased from 2011 to 2013. The loss of the total nitrogen and total phosphorus from farmland accounted for 46.24% and 46.88% respectively. The loss of COD and total phosphorus from fishery accounted for 26.01% and 40.83% respectively and the pollutant contribution kept increasing. The contribution of COD, ammonia nitrogen, total nitrogen and total phosphorus from point source is 37.12%, 44.02%, 21.30% and 7.63%, and from non-point source is 62.88%, 55.98%, 78.70% and 92.37%, respectively. As a result, the management of non-point source is more important than that of point source.

태양광 발전량 예측 도구별 입력 요소 분석 및 실제 발전량 비교에 관한 연구

The objectives of this study are to investigate input variables of photovoltaic generation programs and to compare their prediction to actual generation of photovoltaic system in the C city hall and the C city sewage treatment plant. We investigated the actual amount of generation, the forecast amount of generation, the amount of solar radiation data, and calculated the relative errors. We simulated the photovoltaic system of C city hall and the C city sewage treatment plant located in Chungju using existing programs, such as SAM, RETSCREEN, HOMER, PV SYST, Solar Pro. The result of this study are as follows : Through examining the relative errors of monthly predicted and actual generation data, monthly generation data showed big errors in winter season?. Except winter season, actual amount of generation and the predicted amount of generation showed no large errors.

Assessment of Treating Laundry Wastewater Using Composites Based on Industrial Waste

For a long time, a large number of residential laundry wastewater emissions increased heavy burden to the city sewage treatment plant and brought serious pollution to the surface water. This study uses industrial waste (slag, fly ash) as substrate, mixed with some binder and pore forming agent to produce spherical composite materials for the study on adsorption of washing wastewater. Experiments show that the main pollutants of the laundry wastewater with sodium n-alkyl benzene sulfonate (LAS) are obviously removed.

Case study on pressured microfiltration and reverse osmosis membrane systems for water reuse

According to the announcement by OECD [1], Korea is listed as the most “severe water stress” nation among OECD countries. As competition for restricted water resources is expected in the coming decades, development of technologies for water treatment and reuse becomes urgently needed. The combined microfiltration (MF) and reverse osmosis (RO) process has been one of the mostly employed treatment methods in obtaining recyclable quality for wastewater reclamation and reuse, yet few has reported a pilot-scale investigation with the pressurized MF (without pretreatment) and RO system. The pilot plant operated in Gimcheon City Sewage Treatment Plant consists of a PVDF membrane in pressurized MF (treatment capacity of MF and RO: 30 and 20 m3/day) and a RO unit of wastewater reclamation. The result of the pilot study indicates that the reclaimed water can conform industrial water reuse standard (i.e., Turbidity (MF): 0.05 NTU, TDS (RO): 4.9 mg/L, TOC (RO): 0.79 mg/L). While the recovery rate run at the MF unit was 90%, the RO system was operated at 67%, to reach an overall system recovery rate of 60%. Herein, we report the performance of a pilot-scale pressurized MF and RO system operated for water reuse and discuss possible applications of the system for a test bed.

Analysis of some pharmaceuticals in municipal wastewater of Almadinah Almunawarah

The chemical pollution of water resources is a major challenge facing the humanity in this century. Pharmaceuticals and personal care products (PPCPs) are a group of emerging environmental chemical pollutants distinguished by their bioactivity and high solubility. They may also cause health complications to humans and living organisms. Pharmaceuticals enter the environment, mainly via wastewater and can eventually reach the surface and ground water. Despite this, PPCPs received less attention as environmental pollutants than other chemical pollutants (e.g. heavy metals and pesticides). The purpose of this work was to investigate the presence of some of the most frequently dispensed drugs for the residents of Almadinah Almunawarah, Saudi Arabia in the municipal wastewater before and after treatment. For this purpose, wastewater samples were collected biweekly from the city's sewage treatment plant for a period of 4months and analyzed the targeted drugs using tandem LC–MS. Out of the 19 investigated drugs, 5 pharmaceuticals have been found in concentrations greater than the limit of detection in both the influents and effluents of the sewage treatment plant. As expected, the concentrations of investigated pharmaceuticals in the wastewater were found to be low. These drugs and their average concentrations (in ngmL−1) in the influents were: acetaminophen (38.9), metformin (15.2), norfluoxetine (7.07), atenolol (2.04), and cephalexin (1.88). Meanwhile, the effluents contained slightly lower levels (in ngmL−1) than those of influents: acetaminophen (31.2), metformin (3.19), norfluoxetine (7.25), atenolol (0.545), and cephalexin (1.53). The results of this study supported by many other investigations indicate the inefficiency of current conventional wastewater treatment protocols in eliminating such a group of active and potentially hazardous pollutants from the wastewater.

Sewage Sludge Aerobic Composting Technology Research Progress

This article introduced our country city sewage treatment plant sludge status, as well as the city sewage treatment plant slu dge aerobic composting technology research progress, and introduced the domestic production examples and problems, w hich can be used as a preliminary understanding of aerobic sludge composting techniques.

A Review of Treatment Technique of Remaining Sludge Generated during the Process of Sewage Disposal

With the flooding construction of sewage treatment plants in cities, the production capacity has being increased rapidly. This paper compares the principium and advantages and disadvantages of the treatment methods systematically and proposes to apply the way to reduce the amount of the sludge on site to reduce the production radically and achieve the completed disposal of pollutant of urban wastewater, taken into account the society, economy and environment.

Evaluation of wastewater nitrogen transformation in a natural wetland (Ulaanbaatar, Mongolia) using dual-isotope analysis of nitrate

The Tuul River, which provides water for the daily needs of many residents of Ulaanbaatar, Mongolia, has been increasingly polluted by wastewater from the city's sewage treatment plant. Information on water movement and the transformation of water-borne materials is required to alleviate the deterioration of water quality. We conducted a synoptic survey of general water movement, water quality including inorganic nitrogen concentrations, and isotopic composition of nitrogen (δ15N-NO3−, δ18O-NO3−, and δ15N-NH4+) and water (δ18O-H2O) in a wetland area that receives wastewater before it enters the Tuul River. We sampled surface water, groundwater, and spring water along the two major water routes in the wetland that flow from the drain of the sewage treatment plant to the Tuul River: a continuous tributary and a discontinuous tributary. The continuous tributary had high ammonium (NH4+) concentrations and nearly stable δ15N-NH4+, δ15N-NO3−, and δ18O-NO3− concentrations throughout its length, indicating that nitrogen transformation (i.e., nitrification and denitrification) during transit was small. In contrast, NH4+ concentrations decreased along the discontinuous tributary and nitrate (NO3−) concentrations were low at many points. Values of δ15N-NH4+, δ15N-NO3−, and δ18O-NO3− increased with flow along the discontinuous route. Our results indicate that nitrification and denitrification contribute to nitrogen removal in the wetland area along the discontinuous tributary with slow water transport. Differences in hydrological pathways and the velocity of wastewater transport through the wetland area greatly affect the extent of nitrogen removal.

Silver contamination on abiotic and biotic compartments of Nahuel Huapi National Park lakes, Patagonia, Argentina

The Ag contents of abiotic and biotic compartments of different lakes of Nahuel Huapi National Park, Patagonia, Argentina were analyzed. The water bodies studied were lakes Nahuel Huapi, Moreno, Escondido, Espejo Chico and Traful, the latter chosen as a reference lake. The Ag concentration profiles of short sediment cores, dated by 210Pb and 137Cs techniques, were analyzed, as well as suspended load collected from three sites of lake Nahuel Huapi. The biota studied were the native mussel Diplodon chilensis (digestive gland and total soft tissues pooled samples) and five species of fish, two native and three introduced (liver and muscle pooled samples). Ag contents were determined by Instrumental Neutron Activation Analysis (INAA). The upper layers of the sediment cores sampled in lake Nahuel Huapi were enriched in Ag contents compared to deep layers in accumulation periods corresponding to the second half of the 20th century, but this enrichment was neither observed in the reference lake Traful, nor in lakes Espejo Chico and Escondido. Ag was enriched over background level (0.1 μg g −1) also in suspended load collected in lake Nahuel Huapi. Ag fluxes to sediments were computed for suspended load and enriched sediment core layers. Highest Ag fluxes, from 350 to 470 μg m −2 year −1, were measured in Nahuel Huapi near the site where the liquid effluents of the Bariloche city sewage treatment plant are released to the lake. The spatial distribution of the other Ag fluxes suggests that this is the main source of Ag to lake Nahuel Huapi and lateral transport occurs within the water body. Ag concentrations on biota samples were consistent with these conclusions. Mussels collected in lake Nahuel Huapi showed higher Ag concentrations than in the other lakes, especially when compared to lake Traful. Ag contents in mussels were strongly associated with sediment intake, but enriched probably due to sediment grain size sorting during the intake processes. Evidence of food chain biomagnification of Ag in fish liver was observed. Ag contents in fish liver were higher at lake Nahuel Huapi even considering the high intra-specific variability, with highest values ranging from 10 to 29 μg g −1 dry weight for brown trout and rainbow trout.

Management of Phosphorus and Nitrogen Inputs to Lake Rotorua, New Zealand

The water quality of Lake Rotorua has deteriorated since the 1960s because of excessive phytoplankton growths caused by increased inputs of phosphorus and nitrogen from the Rotorua city sewage treatment plant. Removal of phosphorus alone may produce no measurable improvement in lake condition unless it can be made the limiting nutrient. Even then, this may take a number of years, because of recycling of phosphorus already in the lake system. Removal of nitrogen alone may reduce phytoplankton growth, in the short term (say 5–10 yr) but is not recommended because the algal community may become dominated by heterocystous blue‐green algae, which can meet their nitrogen requirements by fixing dissolved molecular nitrogen and form dense unsightly assemblages. Thus, removal of both nitrogen and phosphorus is recommended. A suggested aim is to restore the lake condition to that which prevailed prior to the 1960s, before widespread public concern about phytoplankton growths developed. The scientific view is that this lake condition is achievable and will reduce the frequency and magnitude of nuisance algal blooms, maintain reasonable water appearance and clarity for recreational purposes, minimize periods of deoxygenation, and reduce internal nutrient inputs. Removal of all sewage effluent from the catchment is expected to achieve the nutrient load reduction that is required. Any sewage discharge increases the risk that the lake condition will be unsatisfactory, but this risk is probably low if the sewage inputs are less then 3 tonnes (t) of phosphorus and 30 t of nitrogen per year.

The Upper James Estuary – A Study in Water Quality Management

The James River has its head waters in the Allegheny Mountains and flows generally southeasterly to Hampton Roads, Chesapeake Bay and thence to the Atlantic Ocean. Below Richmond, Virginia, the river is tidal with the channel meandering through the coastal plains. Below Hopewell it widens to a broad estuary, with a deep navigable channel bordered by tide marshes. The upper estuary, between Richmond and Hopewell, is heavily used for water supply, recreation, and industrial development. The water entering the estuary a few miles upstream of Richmond is of good quality. However, as one reaches Richmond, the quality of the water deteriorates. There are eleven major discharging municipalities and industries within a stretch of twenty two river miles between Richmond and Hopewell. The major factors contributing to water quality problems below the City of Richmond stem from the intermittent discharge from combined sewer overflows (CSOs) coupled with the continuous discharge from the City's sewage treatment plant. The CSOs contribute a large quantity of soluble BOD, suspended solids, settleable solids, and fecal coliforms to the estuary. The City's sewage treatment plant continuously discharges large quantities of ammonia-nitrogen and phosphorus, in addition to BOD and suspended solids. Rational Management and use of the waters of the upper James estuary appear to be critical. The objectives of this paper, therefore, are the discussion of the present water quality and the wastewater discharge reductions required in order to meet certain water quality and water use objectives.