scholarly journals Designed and real hydraulic load of household wastewater treatment plants

2019 ◽  
Vol 40 (1) ◽  
pp. 155-160 ◽  
Author(s):  
Piotr M. Bugajski ◽  
Karolina Kurek ◽  
Dariusz Młyński ◽  
Agnieszka Operacz

Abstract The paper presents the results of the analysis concerning the verification of the actual hydraulic load and the load of organic pollutants compared to the conditions designed for 4 household wastewater treatment plants. The researches were carried out in the annual period from May 2015 to April 2016. Based on the conducted analysis, it was found that objects act as underloaded hydraulically and the actual inflow of sewage to the analysed objects during the research period ranged from 7.3% to 32.7% in relation to the inflow assumed in the project. Furthermore, in the case of loading the treatment plant with the load of pollutants expressed as PE, it was fund that the actual PE values were lower than assumed in the project. Therefore, it is important that the sizes of the series of household sewage treatment plants were selected depending on the individual conditions of household, i.e. the number of inhabitants or the amount of consumed water.

2020 ◽  
Vol 15 (2) ◽  
pp. 142-151
Author(s):  
Peter Lukac ◽  
Lubos Jurik

Abstract:Phosphorus is a major substance that is needed especially for agricultural production or for the industry. At the same time it is an important component of wastewater. At present, the waste management priority is recycling and this requirement is also transferred to wastewater treatment plants. Substances in wastewater can be recovered and utilized. In Europe (in Germany and Austria already legally binding), access to phosphorus-containing sewage treatment is changing. This paper dealt with the issue of phosphorus on the sewage treatment plant in Nitra. There are several industrial areas in Nitra where record major producers in phosphorus production in sewage. The new wastewater treatment plant is built as a mechanicalbiological wastewater treatment plant with simultaneous nitrification and denitrification, sludge regeneration, an anaerobic zone for biological phosphorus removal at the beginning of the process and chemical phosphorus precipitation. The sludge management is anaerobic sludge stabilization with heating and mechanical dewatering of stabilized sludge and gas management. The aim of the work was to document the phosphorus balance in all parts of the wastewater treatment plant - from the inflow of raw water to the outflow of purified water and the production of excess sludge. Balancing quantities in the wastewater treatment plant treatment processes provide information where efficient phosphorus recovery could be possible. The mean daily value of P tot is approximately 122.3 kg/day of these two sources. The mean daily value of P tot is approximately 122.3 kg/day of these two sources. There are also two outflows - drainage of cleaned water to the recipient - the river Nitra - 9.9 kg Ptot/day and Ptot content in sewage sludge - about 120.3 kg Ptot/day - total 130.2 kg Ptot/day.


2009 ◽  
Vol 60 (9) ◽  
pp. 2439-2445 ◽  
Author(s):  
A. Lynggaard-Jensen ◽  
P. Andreasen ◽  
F. Husum ◽  
M. Nygaard ◽  
J. Kaltoft ◽  
...  

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.


2017 ◽  
Vol 35 (1) ◽  
pp. 141-148 ◽  
Author(s):  
Michał Marzec

AbstractThe reliability of removal of selected contaminants in three technological solutions of the household sewage treatment plants was analysed in this paper. The reliability of the sewage treatment plant with activated sludge, sprinkled biological deposit and hybrid reactor (activated sludge and immersed trickling filter) was analyzed. The analysis was performed using the Weibull method for basic indicators of impurities, BOD5, COD and total suspended solids. The technological reliability of the active sludge treatment plant was 70% for BOD5, 87% for COD and 66% for total suspended solids. In the sewage treatment plant with a biological deposit, the reliability values determined were: 30% (BOD5), 60% (COD) and 67% (total suspended solids). In a treatment plant with a hybrid reactor, 30% of the BOD5and COD limit values were exceeded, while 30% of the total suspended solids were exceeded. The reliability levels are significantly lower than the acceptable levels proposed in the literature, which means that the wastewater discharged from the analysed wastewater treatment plants often exceeds the limit values of indicators specified in currently valid in Poland Regulation of the Minister of Environment for object to 2000 population equivalent.


2018 ◽  
Vol 28 (3) ◽  
pp. 121-131 ◽  
Author(s):  
Anita Jakubaszek ◽  
Artur Stadnik

Abstract The article analyzes the effectiveness of individual Actibloc wastewater treatment plants (produced by Sotralentz) working in the technology of low-rate activated sludge in the Sequential Batch Reactor (SBR) system. The assessment of the effectiveness of household wastewater treatment plants was made on the basis of pollutants: BOD5, COD, total suspended solids, total nitrogen and total phosphorus. The research objects were four household sewage treatment plants located in: Lubań, Kłębanowice, Stara Rzeka and Kościan. The efficiency of removing pollutants in the examined facilities was in the range of: BOD5 92.2 ÷ 97.2%, COD 82.6 ÷ 89.9%, total suspended solids 90.2 ÷ 96.2%, total nitrogen 50.8 ÷ 83.1%, total phosphorus 46.5 ÷ 73.6%. The treated wastewater met the requirements set out in the Regulation of the Minister of the Environment on the conditions to be met when discharging sewage into water or soil, and on substances particularly harmful to the aquatic environment (Journal of Laws 2014, item 1800) in terms of indicators such as BOD5, COD, total suspended solids and total nitrogen. The effectiveness of phosphorus removal in the studied treatment plants was much lower.


1992 ◽  
Vol 25 (6) ◽  
pp. 285-300 ◽  
Author(s):  
René Dupont ◽  
Mogens Henze

Modelling of activated sludge wastewater treatment plants is today generally based on the Activated Sludge Model No. 1 combined with a very simple model for the secondary settler. This paper describes the development of a model for the secondary clarifier based on the general flux theory for zone settling, which can be used in combination with the Activated Sludge Model to form a dynamic computer model/program for a wastewater treatment plant. In addition to the flux model, the developed model includes a simple model for predicting the contents of paniculate components in the effluent This latter model is a purely empirical model, which connects the effluent quality with the hydraulic load, suspended solids load and the nitrate load. The paper describes the model and gives some basic examples on computer simulations and verification of the model.


1994 ◽  
Vol 30 (4) ◽  
pp. 25-34
Author(s):  
M. Ettala ◽  
E. Rossi

Seven operational mishaps were specified on the basis of a questionnaire on wastewater treatment plants, some of them large. In this study a process was developed for screening the chemical spill risks to municipal biological sewage treatment plant. Data on wastewater treatment processes, potential spill sources and chemical properties were combined to determine the threshold chemical quantities which may inhibit the removal of carbonaceous material, prevent nitrification and methanogenesis, cause sludge contamination or lead to the aeration capacity being exceeded. Two sewage treatment plants and eleven industrial sites were chosen for field studies. The influence of spill duration and maintenance activities on threshold quantities are discussed. A field survey lasting 1-2 hours at each site was long enough for the most relevant data to be obtained when the screening method developed was applied. Several chemical spill risks to the plants studied were specified. In addition, cases were identified in which failure of the pretreatment facilities for industrial wastewaters could cause severe mishaps at a biological wastewater treatment plant.


This Study Was Made To Study The Use Of Circular Aeration Tanks Instead Of Rectangular One In Wastewater Treatment Plants. The Study Covered The Effect Of Tank Geometric Shape On Action Stability, Effective Parameters Homogeneity And Treatment Efficiency Inside The Aeration Tank And Its Reflection On The Final Sedimentation Tank Performance. A Pilot Scale Was Erected In Balaqs Wastewater Treatment Plant Pilot Consists From Two Lines One Circular Aeration Tank Followed By Final Settling Tank And Second Rectangular Aeration Tank Followed By Final Settling Tank For Comparison Purpose Under The Same Conditions. The Samples Were Taken Continuously For 5 Weeks From The Inlet, Outlet For (Bod, & Tss) To Measure The Aeration Removal Efficiency. Also Measurements Inside Both Types Of Aeration Tanks To Determine The Parameters Of Temperature & Do Distribution And Stability In Different Depths And Sides Of Tank. Also The Consumed Power Had Been Measured. The Results Shows That The Circular Aeration Tank Achieved Better Stability Inside The Tank With Minimal Variation In Both Of Do And Temperature That Varied Widely In The Rectangular Tank Between Different Depths And Also Longitudinally And In Cross Section Directions That Affects Mainly On The Tank Efficiency And The Consumed Power Needed For Surface Aerators Operation. The Circular Safe About 50% Of The Consumed Power That Also Safe In The Construction And Operation Costs For Such Treatment.


1994 ◽  
Vol 30 (4) ◽  
pp. 17-23 ◽  
Author(s):  
B. Evans ◽  
P. Laughton

The province of Ontario is Canada's most populous province with over 8 million residents out of a total population of 27 million. The Province is situated in the eastern portion of North America and stretches from 41°N to 50° N. All the Great Lakes fall within Ontario's boundaries and the Province is estimated to have over 280,000 lakes. The area along Lake Ontario is home to 5 million of the residents who are serviced by 11 large sewage treatment plants. The remaining 403 treatment plants are scattered throughout the province. with an average size of 20 000 m3/d. Ontario Hydro commissioned a study of the wastewater treatment plants to identify the main power users at the various types of sewage treatment plants, as well as potential areas within each plant where significant energy savings could be generated. By using this information, Ontario Hydro hoped to assess the potential to reduce the load and identify any electrical efficiency improvements, fuel switching and load shifting opportunities that may exist as well as the impact of environmental regulations on power saving initiatives. It was found that several major opportunities existed. These included:■ that up to 25% of power currently used can be reduced by introducing energy efficient measures■ of all the unit operations in wastewater treatment plants, aeration accounts for 42% of the power usage, influent and effluent pumping - 20%, and dewatering - 6%. Of this influent and effluent pumping, specifically influent represented the best target area as significant aeration system upgrade had already taken place.


Water ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3410 ◽  
Author(s):  
Iwona Skoczko ◽  
Pawel Puzowski ◽  
Ewa Szatyłowicz

Biological membrane reactors or membrane bioreactors (MBRs) based on pressure separation techniques are placed among the latest and most modern methods of wastewater treatment. Currently, this method is becoming more and more popular and is being implemented in smaller and larger wastewater treatment plants (WWTPs). However, technologists, operators, and managers of small WWTPs often do not understand the MBR technology installed in their sites and need extensive professional and technological information. The aim of this study was to analyze the modernized WWTP in a small town of Wydminy, located in northeastern Poland in the Great Masurian Lakes region, where the traditional secondary settling tank was replaced by an MBR. The effectiveness of wastewater treatment before modernization and after installation of the membrane module was compared. On the basis of the conducted research, it was noted that the operation of the plant after modernization is more cost-intensive. There were additional electricity costs due to ensuring adequate pressure on the membrane. Nevertheless, the obtained results of the removal of contaminants place the plant in Wydminy in the group of the most effective Polish sewage treatment plants, as compared to the results obtained in other facilities. The MBR operation also places high demands on the exploiters, prompting them to observe even the smallest changes. The conducted research is a type of a case study, which could give the readers an understanding of the necessity of traditional WWTP modernization with MBR.


1994 ◽  
Vol 29 (9) ◽  
pp. 69-77 ◽  
Author(s):  
H. Grüttner ◽  
M. Winther-Nielsen ◽  
L. Jørgensen ◽  
P. Bøgebjerg ◽  
O. Sinkjær

More than three years of pilot-plant operation has documented that inhibition of nitrification was found to influence the dimensioning of the largest Danish wastewater treatment plant, which serves a major part of Copenhagen. Hence, a program for investigating the sources of substances inhibitory to nitrification was initiated. Since the number of substances potentially inhibitory to nitrification is very high, the investigations used direct testing of inhibitory effects on nitrification as a tool for the mapping operations. The overall purpose of the investigation was to determine the types of sources of inhibitory substances and to suggest a program for source control to be implemented by the individual municipalities in the catchment area. This paper describes the strategy for sampling and the results of the first two years of activity. Major conclusions have been that the most important sources of inhibitory substances are to be found among the industries, and that nearly all of the industries investigated exhibited some kind of inhibitory effect Further, is was demonstrated that the toxic unit calculation might be used in the quantification of the sources, and that the observed effects could be explained by the chemical substances in the wastewater from the industries. Based on the above described results, a strategy for control of the inhibitory effects at the different levels of the catchment area was suggested.


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