scholarly journals Determination on inhibition effects of coagulants used in wastewater treatment plants on anaerobic digester

2020 ◽  
Vol 82 (9) ◽  
pp. 1877-1884
Author(s):  
Güler Türkoğlu Demirkol ◽  
Gökhan Balcıoğlu ◽  
Nurtaç Öz ◽  
Moiz Elnekave ◽  
Bülent Armağan ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Settling Tank ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
High Concentration ◽  
Biological Methods ◽  
Solids Removal

Abstract Domestic wastewaters causing pollution contain inorganic and/or organic materials. When the domestic wastewater outflows to the receiving waters, it causes physical, chemical, and biological pollution in them, and deteriorates the ecological balance of those waters. In the treatment of wastewater, various treatment methods are available depending on the pollution strength of the wastewater. Besides mechanical and biological methods, wastewater treatment with physicochemical methods is still one of the most effective and economical options. Particularly in wastewater with a high concentration of suspended solids, this method is very successful, and obtaining high suspended solids removal efficiencies is very possible. In this study, the effects of the use of coagulant and coagulant aid to be used in a treatment plant where domestic wastewater treatment is carried out are determined to increase the treatment efficiency of a biological treatment that comes later in the stages of the treatment. The effluent of the pre-settling tank may contain a lot of suspended solids. This presence of excess suspended solids decreases the efficiency at other levels of treatment and causes energy loss. In the experiments, the standard jar and inhibition tests are done as a method. As a result of the conducted studies, it is determined that the FeCl3, Synthetic coagulant LP 526, FeClSO4, and the combination of anionic polyelectrolyte yield the best results in the removal of the parameters of chemical oxygen demand (COD), total suspended solids (TSS), and volatile suspended solids (VSS). While FeCl3, APE 65, APE 85, Synthetic coagulant LP 526, and FeClSO4 did not show any inhibition effect in the sludge, APE 67, CPE 84, and (Al2(SO4)3 are found to cause inhibition in the sludge.

Tracking influent inorganic suspended solids through wastewater treatment plants

2006 ◽  
Vol 54 (8) ◽  
pp. 101-109 ◽  
Author(s):  
G.A. Ekama ◽  
M.C. Wentzel ◽  
S.W. Sötemann
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Settling Tank ◽  
Treatment Plant ◽  
Primary Sludge ◽  
Unit Operations ◽  
Sludge Digestion ◽  
N Removal

From an experimental and theoretical investigation of the continuity of influent inorganic suspended solids (ISS) along the links connecting the primary settling tank (PST), fully aerobic or N removal activated sludge (AS) and anaerobic and aerobic sludge digestion unit operations, it was found that the influent wastewater (fixed) ISS concentration is conserved through primary sludge anaerobic digestion, activated sludge and aerobic digestion unit operations. However, the measured ISS flux at different stages through a series of wastewater treatment plant (WWTP) unit operations is not equal to the influent ISS flux, because the ordinary heterotrophic organisms (OHO) biomass contributes to the ISS flux by differing amounts depending on the active fraction of the VSS solids at that stage.

scholarly journals Resource-building structures hydraulic account for treatment of vehicle washing stations wastewater

2021 ◽  
Vol 264 ◽  
pp. 03013
Author(s):  
Aybek Arifjanov ◽  
Uchqun Umarov ◽  
Akmal Abdullayev
Keyword(s):  
Wastewater Treatment ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Local Treatment ◽  
Settling Tank ◽  
Treatment Plant ◽  
Petroleum Products ◽  
Hydraulic Calculation ◽  
Design Parameters ◽  
Building Structures

The article presents a method for calculating the parameters of treatment facilities to bring the level of precipitation and wastewater from small enterprises, shops, and services of the Republic to the level of sewage and irrigation trays. The aim is to improve the design parameters of resource-efficient wastewater treatment plants and their widespread use, increase the production capacity of local wastewater treatment plants, improve the level of wastewater treatment and prevent environmental degradation. Hydraulic calculation of the design parameters of the settling tank was carried out at the local treatment plant. The precipitator works by precipitating suspended solids and separating petroleum products from the liquid surface. At the local treatment plant, the content of petroleum products in industrial and precipitation effluents was reduced to 3 mg/l, and the number of suspended solids to 1-1.5 mg/l.

scholarly journals MEJORAMIENTO DE LA CALIDAD MICROBIOLÓGICA DE BIOSÓLIDOS GENERADOS EN PLANTAS DE TRATAMIENTO DE AGUAS RESIDUALES DOMÉSTICAS (MICROBIOLOGICAL QUALITY IMPROVEMENT OF BIOSOLIDS FROM DOMESTIC WASTEWATER TREATMENT PLANTS)

Revista EIA ◽  
2013 ◽  
Vol 6 (11) ◽  
pp. 21
Author(s):  
Patricia Torres ◽  
Carlos Madera ◽  
Jorge Silva
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Microbiological Quality ◽  
Domestic Wastewater ◽  
Nutrient Content ◽  
Pilot Scale ◽  
High Concentration ◽  
Domestic Wastewater Treatment ◽  
Class B

Uno de los principales problemas de calidad que presentan los biosólidos de plantas de tratamiento de aguas residuales domésticas –PTAR– es el contenido de microorganismos patógenos que los clasifica en muchos casos como Clase B con restricción para uso agrícola. Este estudio evaluó la estabilización alcalina de los biosólidos de la PTAR Cañaveralejo (Cali, Colombia) para mejorar su calidad microbiológica, empleando dos tipos de cal (hidratada y viva) en dosis entre 8 y 25 % y dos tipos de ceniza con dosis entre 8 y 40 % en unidades experimentales de 0,2 m2 con un tiempo de contacto de 13 días. Los resultados mostraron que con cal se logró reducción total de las variables de respuesta evaluadas (coliformes fecales, Salmonella sp y huevos de helmintos), mientras que el poder alcalinizante de las cenizas evaluadas fue insuficiente. El biosólido higienizado con cal presenta alto potencial de uso agrícola por su calidad microbiológica y por el contenido final de materia orgánica y nutrientes (N, P) que pueden beneficiar los suelos, pero es recomendable evaluar la optimización a escala piloto de la dosificación de cal y la aplicación del biosólido en diferentes tipos de suelos y cultivos para precisar los beneficios o medidas preventivas antes de la aplicación.Abstract: One of the main quality problems of biosolids from domestic wastewater treatment plants –WWTP– is the high concentration of pathogens, often classified as a class B, with restriction for use in agriculture. This study evaluated the alkali stabilization of biosolids from Cañaveralejo wastewater treatment plant (PTAR-C), located in Cali, Colombia, in order to improve their microbiological quality using two types of lime (quick and hydrated) with doses between 8 to 25 % and two types of ash with 8 to 40 % as doses, in experimental units 0,2 m2with 13 days of contact time. The results showed that both type of lime reached the total reduction of evaluated monitoring variables (faecal coliforms, Salmonella sp, helmints eggs) while the alkali power of ashes were lower. The obtained biosolids treated with lime have a high potential use in agriculture purposes for the good microbiological quality, and for the organic matter and nutrient content (N, P) that can generate benefit to the soil, but it is recommendable to evaluate at pilot scale the lime doses and application of biosolid in different soils types and crops in order to precise the benefits or prevent measurements before application of material in soil.

Combined removal of nutrients and suspended solids in a dual-media post-denitrification filter as additional process step of wastewater treatment plants

2013 ◽  
Vol 8 (2) ◽  
pp. 315-322
Author(s):  
A. Sperlich ◽  
P. Geyer ◽  
R. Gnirss ◽  
M. Barjenbruch
Keyword(s):  
Wastewater Treatment ◽  
Suspended Solids ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Soluble Reactive Phosphorus ◽  
Oxygen Demand ◽  
Design Parameters ◽  
Municipal Wastewater Treatment ◽  
Process Step

Operation of a pilot-scale dual-media biological filter as post-denitrification step in a municipal wastewater treatment plant was investigated for 28 months. In order to identify key design parameters, filtration rate, external carbon dosing concentration and strategy as well as backwash frequency were varied. The results show that dual-media biological filtration is able to achieve effluent concentrations of total suspended solids (TSS) ≤2 mg/L and NO3-N ≤ 5 mg/L. TSS removal also leads to a reduction of particulate bound phosphorus and chemical oxygen demand without dosing any precipitant. Soluble reactive phosphorus is required for growth of the denitrifying bacteria and reduced from 0.4 to 0.3 mg/L in the filter effluent, corresponding to approximately 0.02 g P/g NOx-N removed. Depending on NOx-N loading and carbon dosage, average denitrification rates of 0.5–1.0 kg NOx-N/m3*d were achieved in different operational phases. Seasonally varying nitrite formation and breakthrough in the filter effluent were observed and could not be controlled by adjusting carbon dosage and backwash frequency. Effective operational strategies to prevent nitrite breakthrough at NOx-N loads in the range of 1–2 kg NOx-N/m3*d and high influent O2 levels are therefore needed.

Evaluating the treatment performance of a full scale Activated Sludge Plant in Islamabad, Pakistan

2012 ◽  
Vol 7 (1) ◽  
Author(s):  
S. S. Fatima ◽  
S. Jamal Khan
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Suspended Solids ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Full Scale ◽  
Operational Parameter ◽  
Mixed Liquor ◽  
Treatment Performance

In this study, the performance of wastewater treatment plant located at sector I-9 Islamabad, Pakistan, was evaluated. This full scale domestic wastewater treatment plant is based on conventional activated sludge process. The parameters which were monitored regularly included total suspended solids (TSS), mixed liquor suspended solids (MLSS), mixed liquor volatile suspended solids (MLVSS), biological oxygen demand (BOD), and chemical oxygen demand (COD). It was found that the biological degradation efficiency of the plant was below the desired levels in terms of COD and BOD. Also the plant operators were not maintaining consistent sludge retention time (SRT). Abrupt discharge of MLSS through the Surplus Activated sludge (SAS) pump was the main reason for the low MLSS in the aeration tank and consequently low treatment performance. In this study the SRT was optimized based on desired MLSS concentration between 3,000–3,500 mg/L and required performance in terms of BOD, COD and TSS. This study revealed that SRT is a very important operational parameter and its knowledge and correct implementation by the plant operators should be mandatory.

scholarly journals Use of a duckweed pond for the domestic wastewater polishing in Ilha Solteira, SP, Brazil

2017 ◽  
Vol 28 (4) ◽  
pp. 477-489 ◽  
Author(s):  
Daiane Cristina de Oliveira Garcia ◽  
Liliane Lazzari Albertin ◽  
Tsunao Matsumoto
Keyword(s):  
Wastewater Treatment ◽  
Biomass Production ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Treatment System ◽  
Content Type ◽  
Stabilization Pond ◽  
Domestic Effluent ◽  
Duckweed Pond

Purpose The purpose of this paper is to evaluate the efficiency of a duckweed pond in the polishing of a stabilization pond effluent, as well as quantify its biomass production. Once an adequate destination is given to the produced biomass, the wastewater treatment plant can work in a sustainable and integrated way. Design/methodology/approach The duckweed pond consisted of a tank with volume 0.44 m3, operating in continuous flow with an outflow of 0.12 m3/day and hydraulic retention time of 3.8 days. Effluent samples were collected before and after the treatment, with analyzes made: daily-pH, dissolved oxygen and temperature; twice a week – total nitrogen (TN), total phosphorus (TP) and chemical oxygen demand (COD); and weekly – total solids (TS) and Biochemical Oxygen Demand (BOD5). The duckweeds were collected each for seven days for its production quantification. Findings The highest efficiency of TN, TP, COD, BOD5 and TS removal were of 74.67, 66.18, 88.12, 91.14 and 48.9 percent, respectively. The highest biomass production rate was 10.33 g/m2/day in dry mass. Research limitations/implications There was great variation in biomass production, which may be related to the stabilization pond effluent conditions. The evaluation of the effluent composition, which will be treated with duckweeds, is recommended. Practical implications The evaluated treatment system obtained positive results for the reduction in the analyzed variables concentration, being an efficient technology and with operational simplicity for the domestic effluent polishing. Originality/value The motivation of this work was to bring a simple system of treatment and to give value to a domestic wastewater treatment system in a way that, at the same time the effluent polluter level is reduced and it is also possible to produce biomass during the treatment process.

Model-based evaluation of nitrogen removal in a tannery wastewater treatment plant

2004 ◽  
Vol 50 (6) ◽  
pp. 251-260 ◽  
Author(s):  
M.S. Moussa ◽  
A.R. Rojas ◽  
C.M. Hooijmans ◽  
H.J. Gijzen ◽  
M.C.M. van Loosdrecht
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plants ◽  
Computer Modelling ◽  
Treatment Plant ◽  
Domestic Wastewater ◽  
Plant Performance ◽  
Accurate Estimation ◽  
Model Parameters ◽  
Biological Tests

Computer modelling has been used in the last 15 years as a powerful tool for understanding the behaviour of activated sludge wastewater treatment systems. However, computer models are mainly applied for domestic wastewater treatment plants (WWTPs). Application of these types of models to industrial wastewater treatment plants requires a different model structure and an accurate estimation of the kinetics and stoichiometry of the model parameters, which may be different from the ones used for domestic wastewater. Most of these parameters are strongly dependent on the wastewater composition. In this study a modified version of the activated sludge model No. 1 (ASM 1) was used to describe a tannery WWTP. Several biological tests and complementary physical-chemical analyses were performed to characterise the wastewater and sludge composition in the context of activated sludge modelling. The proposed model was calibrated under steady-state conditions and validated under dynamic flow conditions. The model was successfully used to obtain insight into the existing plant performance, possible extension and options for process optimisation. The model illustrated the potential capacity of the plant to achieve full denitrification and to handle a higher hydraulic load. Moreover, the use of a mathematical model as an effective tool in decision making was demonstrated.

Using metazoa to reduce sludge production

1997 ◽  
Vol 36 (11) ◽  
pp. 171-179 ◽  
Author(s):  
J. H. Rensink ◽  
W. H. Rulkens
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Domestic Wastewater ◽  
Brewery Wastewater ◽  
Trickling Filters ◽  
Starting Point ◽  
Nitrification Process ◽  
Sludge Production

Pilot plant experiments have been carried out to study the mineralization of sludge from biological wastewater treatment plants by worms such as Tubificidae. Trickling filters filled with lava slags were continuously fed with a certain quantity of excess activated sludge of a Dutch brewery wastewater treatment plant (Bavaria) by recirculation during 10 to 14 days. At the starting point of each experiment the trickling filters were inoculated with Tubificidae. Recirculation of sludge showed that use of Tubificidae resulted in a COD reduction of the sludge (mixed liquor) of 18–67–. Without worms this reduction was substantially lower. The sludge production in a pilot activated sludge system for treating settled domestic wastewater reduced from 0.40 to 0.15 g MLSS/g COD removed when Tubificidae were added to the system. The lower amounts of sludge were always accompanied by an increase of nitrate and phosphate concentration in the wastewater. There was no disturbance of the nitrification process. Application of Tubificidae or other worms may have interesting potential for practical application.

Increased performance of secondary clarifiers using dynamic distribution of minimum return sludge rates

2009 ◽  
Vol 60 (9) ◽  
pp. 2439-2445 ◽  
Author(s):  
A. Lynggaard-Jensen ◽  
P. Andreasen ◽  
F. Husum ◽  
M. Nygaard ◽  
J. Kaltoft ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Suspended Solids ◽  
Considerable Increase ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Total Flow ◽  
Equal Distribution ◽  
Solids Concentration ◽  
Hydraulic Load ◽  
And Control

Most wastewater treatment plants have several secondary clarifiers or even more sets of clarifiers including several secondary clarifiers, and in practice it is a well known problem that equal distribution of the load to the single clarifier (or set of clarifiers) is very difficult—not to say impossible—to obtain. If the problem is neglected, quite a big percentage of the total clarifier capacity—measured as the max. allowed hydraulic load—can be lost. Further, return sludge rates are seldom controlled by any other means than as a (typically too high) percentage of the inlet to the wastewater treatment plant—giving a varying and too low suspended solids concentration in the return sludge, which again can lead to an unnecessary use of polymer in the pre-dewatering of the surplus sludge taken from the return sludge. A control of the return sludge rate divided into two parts - control of the total return sludge flow and control of how the total flow shall be distributed between the secondary clarifiers - is able to solve the mentioned problems. Finally, as shall be demonstrated on full scale wastewater treatment plants, a considerable increase of the hydraulic capacity of the treatment plants can be obtained.

Sign in / Sign up

Export Citation Format

Share Document