Research on the Impact of Precipitates Produced with Fe2+ as a Coagulant Plays on Water Quality

2014 ◽  
Vol 687-691 ◽  
pp. 4339-4342
Author(s):  
Ying Zhang ◽  
Lei Zhu ◽  
Jie Fan
Keyword(s):  
Water Quality ◽  
Activated Sludge ◽  
Significant Influence ◽  
Phosphorus Removal ◽  
Treatment Process ◽  
Sewage Treatment ◽  
Phosphate Content ◽  
Change Trend ◽  
The Impact

Fe2+ is widely used as a coagulant to enhance the primary SBR sewage treatment process. Based on SBR system, this paper studies the change trend of phosphate content in various stages by simulating the interaction between sewage and the precipitates produced with Fe2+ in the sediment as a coagulant. The results indicate that excluding the impact of activated sludge, the concentration of PO43+ increases in the end of the anaerobic stage with the increase of FePO4 cumulant in the sediment and there is an equimultiple relationship between the increase of the concentration of PO43+ in the effluent and the FePO4 dosage and that the accumulation of Fe (OH)3 can contribute to the subsequent sustainable phosphorus removal, but the cumulant increase of Fe (OH)3 has no significant influence on the effects of phosphorus removal.

scholarly journals Unravelling diversity and metabolic potential of microbial consortia at each stage of leather sewage treatment

RSC Advances ◽  
2017 ◽  
Vol 7 (66) ◽  
pp. 41727-41737 ◽  
Author(s):  
Hebin Liang ◽  
Dongdong Ye ◽  
Lixin Luo
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Treatment Process ◽  
Sewage Treatment ◽  
Microbial Consortia ◽  
Biological Wastewater Treatment ◽  
Metabolic Potential ◽  
Ecological Functions ◽  
Wastewater Treatment Process ◽  
System P

Activated sludge is essential for the biological wastewater treatment process and the identification of active microbes enlarges awareness of their ecological functions in this system.

Integrated management of the Upper Mersey river basin using the SMILE object-oriented software system

2002 ◽  
Vol 46 (6-7) ◽  
pp. 105-112 ◽  
Author(s):  
M. Spanou ◽  
D. Chen
Keyword(s):  
Water Quality ◽  
River Water ◽  
Integrated Management ◽  
Sewage Treatment ◽  
Object Oriented ◽  
River Water Quality ◽  
Alternative Methods ◽  
River Flows ◽  
Total Ammonia ◽  
The Impact

This paper presents the application of the object-oriented framework SMILE to the management of flows and water quality in the Upper Mersey river catchment. The design river flows are those exceeded for 95% of the time, and are estimated applying alternative methods. The influence of compensation reservoirs, surface-water abstractions, and continuous discharges on low river flows is quantified. The annual licensed abstraction volumes are further reviewed. The monitored river water quality is classified using the River Ecosystem scheme. The compliance of the sewage treatment works and trade effluents with their discharge-consent limits is also assessed. The impact of effluents on the variation of river water quality is evaluated through Monte Carlo simulations at the discharge points. The points where the downstream water quality fails to comply with proposed River Quality Objectives are identified. The consent limits of the corresponding discharges are assessed, and changes to the BOD and total ammonia limits are suggested.

Research of Water Quality in Typical Low Permeability Oilfield Produced Water Treatment

2014 ◽  
Vol 556-562 ◽  
pp. 867-871
Author(s):  
Qiu Shi Zhao
Keyword(s):  
Water Quality ◽  
Oil Recovery ◽  
Treatment Process ◽  
Produced Water ◽  
Sewage Treatment ◽  
Oil Fields ◽  
Water Separation ◽  
Oil Water Separation ◽  
Oilfield Produced Water ◽  
Oil Water

It is significative to study sewage treatment process in low permeable oil fields. It could enhance the oil recovery. The water quality characteristics and oil/water separation characteristics were researched during different period process by GC-MS. It shows that there are about 108 kinds of organic matters, including 45 kinds of aliphatic hydrocarbon, 7 kinds of aine, 5 kinds of sulfocompound and 9 kinds of hexacyclic compounds, such as Benzene, phenol, naphthalene and anthracene. The percent of oil droplets which size was less than 10μm is 57.3%, compared to 91.6% which size was more than 50μm. It is difficult to separate the water and oil. The remaining oil was emulsified oil. The process was hard to decrease COD, and some pollutants were existed in water, such as Arsenic, Selenium, Mercury ,Cadmium and Cr6+. It is further proposed to optimize and develop this process to removal oil and suspended solids.

scholarly journals Co-optimisation of phosphorus and nitrogen removal in stormwater biofilters: the role of filter media, vegetation and saturated zone

2014 ◽  
Vol 69 (9) ◽  
pp. 1961-1969 ◽  
Author(s):  
Bonnie J. Glaister ◽  
Tim D. Fletcher ◽  
Perran L. M. Cook ◽  
Belinda E. Hatt
Keyword(s):  
Water Quality ◽  
Nutrient Removal ◽  
Phosphorus Removal ◽  
Saturated Zone ◽  
Filter Media ◽  
Nitrogen And Phosphorus ◽  
Nitrogen And Phosphorus Removal ◽  
Quality Guidelines ◽  
The Impact

Biofilters have been shown to effectively treat stormwater and achieve nutrient load reduction targets. However, effluent concentrations of nitrogen and phosphorus typically exceed environmental targets for receiving water protection. This study investigates the role of filter media, vegetation and a saturated zone (SZ) in achieving co-optimised nitrogen and phosphorus removal in biofilters. Twenty biofilter columns were monitored over a 12-month period of dosing with semi-synthetic stormwater. The frequency of dosing was altered seasonally to examine the impact of hydrologic variability. Very good nutrient removal (90% total phosphorus, 89% total nitrogen) could be achieved by incorporating vegetation, an SZ and Skye sand, a naturally occurring iron-rich filter medium. This design maintained nutrient removal at or below water quality guideline concentrations throughout the experiment, demonstrating resilience to wetting–drying fluctuations. The results also highlighted the benefit of including an SZ to maintain treatment performance over extended dry periods. These findings represent progress towards designing biofilters which co-optimise nitrogen and phosphorus removal and comply with water quality guidelines.

Study on Sewage Disposal by Bio-Film Process Dosing with Enzyme

2011 ◽  
Vol 236-238 ◽  
pp. 478-481
Author(s):  
Zheng Hua Liu ◽  
Hong Ying Chen
Keyword(s):  
Treatment Process ◽  
Sewage Treatment ◽  
Sewage Disposal ◽  
Promotion Effect ◽  
The Impact

The paper studied enhanced treatment of sewage from discharging points of rivers by bio-film process dosing with enzyme and investigated the promotion effect of enzyme on treatment of sewage by bio-film process. The removal of phenol in sewage was also researched. The experiments results indicated that during the ebb tide, the remove rate of phenol was stable (33%) on the eighth day in the dosing pools and it was stable (31.6%) on the eighth day in the contrast pool. During the rising tide, the remove rate of phenol was stable (30%) on the eighth day in the dosing pools and it was stable (27.2%) on the eighth day in the contrast pool. It indicated that enzyme had good promotion effect on bio-film process during the sewage treatment process. Biological accelerator-bio-film process could effectively reduce the impact of sewage on river and it had a good application prospect as the auxiliary means for water restore.

Study of food waste degradation in a simulated septic tank

2019 ◽  
Vol 37 (12) ◽  
pp. 1199-1206
Author(s):  
Hongjian Lin ◽  
Yuchuan Wang ◽  
Leif van Lierop ◽  
Carlos Zamalloa ◽  
Casey Furlong ◽  
...  
Keyword(s):  
Water Quality ◽  
Food Waste ◽  
Sewage Treatment ◽  
Domestic Wastewater ◽  
Lower Percentage ◽  
Septic Tank ◽  
Septic Systems ◽  
Percentage Increase ◽  
Septic System ◽  
The Impact

Septic systems are typically designed to treat domestic wastewater from households without access to centralized facilities. The installation of a food waste disposer (FWD) may increase the discharge of food waste (FW) into the wastewater; therefore, the installation of a FWD is discouraged in households that have a septic system. This study was conducted to determine how a typical dose of FW from a FWD can affect the performance of a septic system in terms of sewage treatment and solids accumulation. A 20-L control tank was compared with an experiment tank to which FW was added, increasing the amount of total suspended solids (TSS) by 31.3% and total chemical oxygen demands by 46.3% for a period of 110 days. Although the influent water quality changed dramatically, the effluent from the experiment tank had a substantially lower percentage increase in water quality parameters compared with the effluent from the control. It was found that in the experiment tank, 75.8% of FW TSS was degraded, whereas only 36.7% of sewage TSS was degraded, and that 18.8% of FW TSS and 44.9% of sewage TSS accumulated in the experiment tank. The addition of FW increased the scum accumulation, even though the dry matter of the scum layer was much less in quantity than the sludge layer. It also increased the lipid content in the sludge. The increase in the scum layer was mainly due to the increase in protein from the addition of the FW. Overall, compared with sewage TSS, FW TSS tends to be more biodegradable, which indicates that the impact on pumping frequency from adding FW will be insignificant.

The impact of sea water flushing on biological nitrification-denitrification activated sludge sewage treatment process

2002 ◽  
Vol 46 (11-12) ◽  
pp. 209-216 ◽  
Author(s):  
S.M. Yu ◽  
W.Y. Leung ◽  
K.M. Ho ◽  
P.F. Greenfield ◽  
W.W. Eckenfelder
Keyword(s):  
Activated Sludge ◽  
Capital Investment ◽  
Sea Water ◽  
Initial Period ◽  
Sewage Treatment ◽  
Ammonia Nitrogen ◽  
Inhibitory Effects ◽  
Original Design ◽  
Activated Sludge Processes ◽  
The Impact

The process performance of the two largest activated sludge processes in Hong Kong, the Sha Tin and the Tai Po Sewage Treatment Works (STW), deteriorated in the initial period after the introduction of seawater flushing in 1995 and 1996, respectively. High effluent ammonia nitrogen (NH4-N) and total suspended solids (TSS) in excess of the discharge standards resulted from incomplete nitrification and changes in floc characteristics. A desktop study on the inhibitory effects of salinity, particularly on nitrification, was subsequently conducted using the Tai Po STW operating data. To assist the upgrade of the Sha Tin STW a five-month extensive bench-scale investigation on a simple but flexible modified Ludzack-Ettinger configuration with bio-selector was conducted to quantify the inhibitory effects due to the saline concentration. The Sha Tin STW upgrade consists of restoration of its original design capacity (conventional process) of 205,000 m3/day from its currently much reduced capacity as a Bardenpho process. Only the volume of the existing biological process and clarifier is to be utilized. The saline concentration ranges from 3,500 up to 6,500 mg Cl-/L, both daily and seasonally. High and greatly fluctuating saline concentrations have been known to inhibit nitrification. Design consideration should also be given to the peak daily and seasonal TKN loading of up to three times the average. Although the nitrifiers maximum specific growth rate was significantly reduced to a low 0.25 day−1, the inhibition was considered to be tolerable with effluent NH4-N and NO3-N consistently at < 1 and < 6 mg/L. The bio-selector was demonstrated to be efficient in control of sludge foaming and bulking with SVI consistently ≤ 125 mL/g. Results from the IAWQ Model No. 1 and the hydraulic model of the secondary clarifiers allowed overall process capacity maximization. With an anoxic mass fraction of 25-30%, operating sludge age of 9-14 days and SVI ≤ 125 mL/g, both the design requirements and the effluent discharge standards could be met. Without these investigations, an unnecessarily large reaction basin and secondary clarifier volume, and hence capital investment, would have resulted.

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