scholarly journals Quick start-up of Mudanjiang wastewater treatment plant and factors influencing phosphorous removal

2013 ◽  
Vol 8 (1) ◽  
pp. 1-8
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Phosphorus Removal ◽  
Treatment Plant ◽  
Phosphorus Release ◽  
Aeration Tank ◽  
Phosphorous Removal ◽  
Start Up ◽  
The One

Successful start-up of a full-scale wastewater treatment plant (WWTP) is a key issue for the succeeding operation of WWTP on the one hand and the nutritious phosphorus removal is of great concern on the other. After the construction of Mudanjiang WWTP with a flow rate of 100,000 m3 d-1 in Heilongjiang Province of China, a novel way of start-up through feeding wastewater continuously into the system was attempted against the conventional start-up method of inoculating activated sludge in the aeration tank by feeding wastewater intermittently. Activated sludge was cultivated and proliferated in the aeration tanks instead of dosing acclimated sludge from other source. After one-month’s start-up operation, MLSS, SV and SVI increased to 2.5 kg m-3, 30% and nearly 80% respectively, which indicated that quick and simple start-up had been achieved. After successful start-up, an investigation into phosphorus removal was conducted with the emphasis on influencing factors such as ORP and NOx-N concentration etc. When the aeration tank was switched from aerobic to anaerobic mode, phosphorus removal efficiency of 80% could be realized within the whole treatment system. Experimental results revealed that an ORP of -140 mV and NOX-N of 2 mg l-1 were critical for the anaerobic phosphorus release, and DO in the range of 1.7-2.5 mg l-1, BOD5/TP of 20-30 and SVI of 70~80 as well as SRT of 5 days were the optimal phosphorus removal conditions for the aeration tanks.

scholarly journals "Aeration Tank Behavior in the Activated Sludge Wastewater Treatment Plant Startup Conditions Case study; (Wastewater Treatment plant of General Mosul hospital- IRAQ)"

2013 ◽  
Vol 1 (1) ◽  
pp. 1-13
Author(s):  
Riyadh M. S. Al-Obaidi
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Organic Content ◽  
Aeration Tank ◽  
Surface Aeration ◽  
Start Up ◽  
Simple Growth

The biological unit in the wastewater treatment plants can be considered the most sensitive treatment units. It begins work with dynamic conditions for several weeks until reach the steady state conditions. Therefore, this study was done to observe aeration tank behavior (activated sludge unit) in the wastewater treatment plant of general hospital complex of Mosul city. Sampling made daily for more than 30 days. The biological treatment monitoring parameter was tested. The study shown that there is need to about 45-60 days to complete the start up work to be the operation stable and successful (if it worked without seeding). There was simple growth of microorganisms with modest treatment of organic matter, and then it rose after 3 first weeks of operation. There was contrary relationship between organic content and suspended solids in the aeration tank; an equation of this relation has been presented. The pH has risen in the first days in the effluent wastewater, then return to be less than influent pH with a relative relation with the activity of the microorganisms and surface aeration in the tank. The EC was simply reduced in the Effluent along with the study.

A new method of biological start-up in Arak activated sludge wastewater treatment plant

2013 ◽  
Vol 8 (2) ◽  
pp. 234-243 ◽  
Author(s):  
Abdolreza Khalili ◽  
Mohammad Reza Mohebi ◽  
Mohammad Mohebi ◽  
Farideh Ashouri
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Treatment Plant ◽  
New Method ◽  
Cold Weather ◽  
Similar Treatment ◽  
Start Up ◽  
Seed Saving ◽  
Foam Forming

Starting up a wastewater treatment plant (WWTP) is one of the most important stages of operation. A new method was used to start Arak activated sludge WWTP up, which took in advantages of the other methods. Primarily just one of the basins was in the lane and wastewater entered the plant part by part. At first 1/30, second week 1/15, third week 1/6, and fourth week 1/3 of total inflow came to the plant. Observing little progress of biomass gain, some sludge from a similar treatment plant was added to the system, as seed. This procedure continued so the MLSS of the system, attained the 1/3 total design MLSS which was design MLSS of one basin. In the next two weeks, by using developed sludge of the self-system the second and third basins came in the lane and inflow increased to 2/3 and total flow, respectively. Finally after two months of beginning the start-up and one month after adding the seed total desired biomass was developed and the plant started to waste sludge. Because of cold weather start-up period took a longer time than expected. But even before developing biomass environment friendly results were achieved. After attaining design MLSS, BOD5 and COD removal from 40% and 60% increased to 90% and TSS removal from 70% reached to 96%. Less loading, less foam forming, no bacteriologic and chemical problems, better process control, using less seed, saving costs in sludge transport and avoiding relevant problems were the main advantages of this method.

Evolution of the Southpest Wastewater Treatment Plant

2000 ◽  
Vol 41 (9) ◽  
pp. 7-14
Author(s):  
A. Jobbágy ◽  
B. Literáthy ◽  
F. Farkas ◽  
Gy. Garai ◽  
Gy. Kovács
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Phosphorus Removal ◽  
Treatment Plant ◽  
Low Flow ◽  
Nitrate Content ◽  
Nitrogen And Phosphorus ◽  
Treated Effluent ◽  
Processing Wastes

The treated effluent of the Southpest Wastewater Treatment Plant is discharged into a small, low-flow branch of the Danube susceptible to eutrophication. The first, high-load activated sludge system with a hydraulic retention time of 2.5 hrs in the aerated basins, was installed here in 1966. The paper presents the evolution of the technology by illustrating the effects of the different changes carried out since 1991. Reconfiguration of the existing activated sludge basins connected originally in parallel into an arrangement of tanks in series increased the settleability of the sludge as well as the efficiency of COD removal significantly. Introduction of an anaerobic zone preceding the aerated basins facilitated biological excess phosphorus removal with a consequent release in the thickener and digester. Introducing lime addition into the recycled sludge processing wastes significantly improved the performance of the system. However, since there had been no provision built for eliminating the nitrate content of the recycled sludge, efficiency of phosphorus removal proved to be dependent on the eventually occurring nitrification. In order to achieve both an effective nitrogen and phosphorus removal the current technology established in 1999 applies a nitrification and a denitrification filter following the activated sludge unit and uses precipitation for phosphorus removal.

Phosphorus Releasing from Surplus Activated Sludge by Ultrasonic Pretreatment

2014 ◽  
Vol 878 ◽  
pp. 702-707 ◽  
Author(s):  
Chang Liu ◽  
Ping Zeng ◽  
Yong Hui Song ◽  
Jian Guang Cheng ◽  
Chao Wei Zhu ◽  
...  
Keyword(s):  
Organic Matter ◽  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Municipal Wastewater ◽  
Treatment Plant ◽  
Phosphorus Release ◽  
Phosphorus Recovery ◽  
Municipal Wastewater Treatment ◽  
Before And After

Three kinds of surplus activated sludge were pretreated by alkali and combination of alkali and ultrasonic. The changes of PO43-P, TP, SCOD, TOC, TS, VS before and after pretreatment were investigated. The results showed that phosphorus and organic matter could be released into supernatant both by alkali and ultrasonic. The surplus activated sludge from municipal wastewater treatment plant was easier to be broken than that from pharmaceutical wastewater treatment plant. The activated sludge from Qinghe wastewater treatment plant could be selected for further phosphorus recovery since the largest quantity of phosphorus release and the lowest organic matter release ratio among the three kinds of surplus activated sludge.

scholarly journals Determination of methyl mercury in a pilot-scale activated sludge wastewater treatment plant

2013 ◽  
Vol 8 (1) ◽  
pp. 61-67 ◽  
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Methyl Mercury ◽  
Treatment Plant ◽  
Pilot Scale ◽  
Photochemical Reactions ◽  
Synthetic Wastewater ◽  
Aeration Tank

The methylation of mercury has been investigated and documented mainly in sediments, fish and microorganisms, while limited number of relevant studies is available for wastewater. The procedure of mercury methylation can occur via biological pathway (by microorganisms) and via chemical or photochemical reactions. Methylation of mercury occurs mainly under anaerobic conditions, but some studies have shown its existence also under aerobic conditions. The resulting concentration of methyl mercury, which is a highly toxic compound, depends on the specific rates of methylation/demethylation of mercury. The factors affecting these procedures are the availability of inorganic mercury, pH, organic matter concentration, microbial activity, redox potential and temperature. Bacteria which can methylate mercury are often present in wastewater, and, therefore, the formation of methyl mercury during wastewater treatment is possible. The objective of the present investigation was the determination of methyl mercury in a pilotscale activated sludge wastewater treatment plant supplied with synthetic wastewater enriched with mercury. For this purpose, a Liquid-Liquid Extraction / Simultaneous Derivatization - GC/MS method was developed and applied for the analysis of samples from the aeration tank, from the treatment plant effluent and from the sludge. Methyl mercury was not detected in the samples (detection limit 0.07 μg l-1), leading to the conclusion that mercury is not methylated under the particular experimental conditions of the pilot-scale water treatment plant.

scholarly journals CONTROLLING FACTORS OF NITROUS OXIDE EMISSIONS FROM A CONVENTIONAL ACTIVATED SLUDGE WASTEWATER TREATMENT PLANT

Engevista ◽  
2015 ◽  
Vol 17 (3) ◽  
pp. 375 ◽  
Author(s):  
Renato Pereira Ribeiro ◽  
Jaime Lopes da Mota Oliveira ◽  
Débora Cynamon Kligerman ◽  
Renata Barbosa Alvim ◽  
Samara Almeida Andrade ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Treatment Plant ◽  
Nitrous Oxide Emissions ◽  
Aeration Tank ◽  
N2o Emissions ◽  
Air Stripping ◽  
Conventional Activated Sludge

Nitrous oxide emissions were determined in three campaigns in the aeration tank of a full scale conventional activated sludge wastewater treatment plant. During these experiments, the carbonaceous organic matter (BOD and COD) removal was high and rather constant (97-98% and 93-96%). The results indicate that the concentration of total nitrogen in the influent wastewater, especially NH4+, and the aeration flow rate are key controlling factor of N2O emissions from the aeration tank. Nitrification was the major source of N2O, suggested by the behavior of DO concentrations, NO3-/NH4+ ratio and pH values along the six interlinked zones of the aeration tank. Excessive air flow intensified N2O transfer from the liquor to the atmosphere by air stripping.

Disposal of Alum Sludge to the Existing Activated Sludge Wastewater Treatment Plant

1973 ◽  
Vol 8 (1) ◽  
pp. 36-67 ◽  
Author(s):  
Deh Yuan Hsu
Keyword(s):  
Wastewater Treatment ◽  
Water Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Settling Tank ◽  
Treatment Plant ◽  
Wastewater Sludge ◽  
Treated Wastewater ◽  
Aeration Tank ◽  
Alum Sludge

Abstract For finding the practicability of discharging water treatment plant sludge into the municipal sewer, the effects of synthetic aluminum hydroxide floc on several major units in an activated sludge wastewater treatment process were studied. It was found that the crucial effects were the increase in sludge production, either in the primary settling tank or in the secondary settling tank, and the retardation of the digestibility of the wasted sludge. The treatment efficiency, in terms of the quality of the treated wastewater, however, was improved. No toxic effects were found in the study of the functions of organic matter removal and the nitrification of activated sludge with the addition of aluminium hydroxide up to 300 mg Al/1 to the mixed liquor. The dewatering property of the wastewater sludge was improved with the addition of this chemical floc. Two processes are suggested. One is to discharge alum. sludge into the sewer at a suitable rate and the other is to discharge the water treatment wastes into a thickener in the wastewater treatment plant. The concentrated underflow can be mixed with the regular digested sludge for dewatering while the supernatant can be discharged either to the primary settling tank or to the aeration tank.

Rehabilitation and Upgrading of the Beni Suef City Wastewater Treatment Plant

1990 ◽  
Vol 22 (7-8) ◽  
pp. 131-138
Author(s):  
Ahmed Fadel
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Treatment Plant ◽  
Primary Treatment ◽  
High Rate ◽  
Shock Load ◽  
Economic Evaluations ◽  
Activated Sludge Process ◽  
Trickling Filter

Many of Egypt's cities have existing treatment plants under operation that have been constructed before 1970. Almost all of these treatment plants now need rehabilitation and upgrading to extend their services for a longer period. One of these plants is the Beni Suef City Wastewater Treatment Plant. The Beni Suef WWTP was constructed in 1956. It has primary treatment followed by secondary treatment employing intermediate rate trickling filters. The BOD, COD, and SS concentration levels are relatively high. They are approximately 800, 1100, and 600 mg/litre, respectively. The Beni Suef city required the determination of the level of work needed for the rehabilitation and upgrading of the existing 200 l/s plant and to extend its capacity to 440 l/s at year 2000 A description of the existing units, their deficiencies and operation problems, and the required rehabilitation are presented and discussed in this paper. Major problems facing the upgrading were the lack of space for expansion and the shortage of funds. It was, therefore, necessary to study several alternative solutions and methods of treatment. The choice of alternatives was from one of the following schemes: a) changing the filter medium, its mode of operation and increasing the number of units, b) changing the trickling filter to high rate and combining it with the activated sludge process, for operation by one of several possible combinations such as: trickling filter-solids contact, roughing filter-activated sludge, and trickling filter-activated sludge process, c) dividing the flow into two parts, the first part to be treated using the existing system and the second part to be treated by activated sludge process, and d) expanding the existing system by increasing the numbers of the different process units. The selection of the alternative was based on technical, operational and economic evaluations. The different alternatives were compared on the basis of system costs, shock load handling, treatment plant operation and predicted effluent quality. The flow schemes for the alternatives are presented. The methodology of selecting the best alternative is discussed. From the study it was concluded that the first alternative is the most reliable from the point of view of costs, handling shock load, and operation.

Operational Results of the Wolfsburg Wastewater Treatment Plant

1992 ◽  
Vol 25 (4-5) ◽  
pp. 203-209 ◽  
Author(s):  
R. Kayser ◽  
G. Stobbe ◽  
M. Werner
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Nitrogen Content ◽  
Total Nitrogen ◽  
Nitrogen Removal ◽  
Wastewater Treatment Plant ◽  
Treatment Plant ◽  
Phosphate Removal ◽  
Total Nitrogen Content ◽  
Activated Sludge Process

At Wolfsburg for a load of 100,000 p.e., the step-feed activated sludge process for nitrogen removal is successfully in operation. Due to the high denitrification potential (BOD:TKN = 5:1) the effluent total nitrogen content can be kept below 10 mg l−1 N; furthermore by some enhanced biological phosphate removal about 80% phosphorus may be removed without any chemicals.

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