BTEX degradation in a cold-climate wetland system

A pilot-scale subsurface vertical-flow wetland system was constructed at the former BP Refinery in Casper, Wyoming in order to determine benzene, toluene, ethylbenzene and xylene (BTEX) degradation rates in a cold-climate application. The pilot system, consisting of 4 cells, each dosed at a nominal flow rate of 5.4 cubic metres per day, was operated between August and December 2002. The pilot tested the effects of wetland mulch and aeration on system performance. Areal rate constants (kA values) were calculated based on an assumed three tanks in series (3TIS). The presence of wetland sod and aeration both improved treatment performance. Mean kA values were 244 m/yr for cells without sod or aeration, and improved to 356 m/yr for cells with sod and aeration. Based on the results of the pilot system, a full-scale wetland system (capable of operating at 6,000 m3/day) was started up in May 2003. The full-scale system achieved permit compliance within one week of startup, but is currently being loaded at only 45% of the design hydraulic load, and 15% of the design BTEX mass load, resulting in a mean kA value of ∼350 m/yr.

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Wastewater Lagoons in a Cold Climate

Water Science & Technology ◽

10.2166/wst.1987.0125 ◽

1987 ◽

Vol 19 (12) ◽

pp. 47-53 ◽

Cited By ~ 4

Author(s):

J. A. Oleszkiewicz ◽

A. B. Sparling

Keyword(s):

Control Mechanism ◽

Maximum Load ◽

Domestic Sewage ◽

Full Scale ◽

Cold Climate ◽

Odor Control ◽

Intermittent Rivers ◽

In Series ◽

Break Up ◽

Lagoon Systems

Severe climate, intermittent rivers and availability of land make facultative lagoon systems the method of choice in treating primarily domestic sewage from smaller municipalities. The lagoons are designed on a recommended maximum load of 55 kgBOD5/ha d to first cell, while the second cell provides storage. The discharge is twice annually and the occurrence of the spring ice break-up odor period is one of the primary criteria limiting this load. Based on full scale performance data, it is demonstrated that, from the standpoint of odor nuisance, the load to the first cell should be kept equal to or less than 35 kg/ha d. Full scale studies of an overloaded lagoon system show the futility of under-ice aeration for odor control. Mechanism of natural odor control during ice break up is elucidated. Upgrading of the overloaded systems or lagoons receiving significant industrial contribution is best achieved by construction of a 3–5 m deep aerated lagoon preceding the two or more facultative cells in series.

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The use of constructed wetlands to upgrade treated sewage effluents before discharge to natural surface water in texel island, The Netherlands – pilot study

Water Science & Technology ◽

10.2166/wst.1997.0205 ◽

1997 ◽

Vol 35 (5) ◽

pp. 231-237 ◽

Cited By ~ 6

Author(s):

M. Schreijer ◽

R. Kampf ◽

S. Toet ◽

J. Verhoeven

Keyword(s):

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Chemical Precipitation ◽

Pilot Scale ◽

E Coli ◽

System A ◽

Treated Sewage ◽

Wetland System ◽

High Degree

Since 1988 experiments have been carried out on a pilot scale on polishing of sewage treatment plant (STP) effluent in a constructed wetland system, a combination of a macrophyte bed and a lagoon. The hydraulic retention time (HRT) has been between one and ten days. At HRTs of 2-3 days a favourable oxygen regime and a high degree of removal of E. coli bacteria could be obtained. The natural alternation of low and high oxygen levels resulted in an extra nitrogen removal from the low levels of nitrogen in the effluent of the STP. Phosphorus removal in the wetland system under these conditions was low, therefore chemical precipitation has to take place in the STP. The favourable results of the study have led to the construction of a full scale 3.5 ha wetland system for the treatment of 3500 m3 effluent day−1 in 1994. The HRT is 2.1 days at dry weather flow. The purpose of this wetland is to further polish the STP effluent in order to match the water quality of the natural local surface waters.

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COLIFORM BACTERIA REMOVAL FROM SEPTIC WASTEWATER IN A PILOT-SCALE COMBINED CONSTRUCTED WETLAND SYSTEM

Environmental Engineering and Management Journal ◽

10.30638/eemj.2012.233 ◽

2012 ◽

Vol 11 (10) ◽

pp. 1873-1879 ◽

Cited By ~ 21

Author(s):

Bilal Tuncsiper ◽

Selma C. Ayaz ◽

Lutfi Akca

Keyword(s):

Constructed Wetland ◽

Pilot Scale ◽

Coliform Bacteria ◽

Wetland System ◽

Bacteria Removal

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Municipal wastewater treatment with pond–constructed wetland system: a case study

Water Science & Technology ◽

10.2166/wst.2005.0491 ◽

2005 ◽

Vol 51 (12) ◽

pp. 325-329 ◽

Cited By ~ 18

Author(s):

X. Wang ◽

X. Bai ◽

J. Qiu ◽

B. Wang

Keyword(s):

Constructed Wetland ◽

Municipal Wastewater ◽

Municipal Wastewater Treatment ◽

Oxidation Pond ◽

System A ◽

Treated Effluent ◽

Wetland System ◽

Oxidation Ponds ◽

Better Than

The performance of a pond–constructed wetland system in the treatment of municipal wastewater in Kiaochow city was studied; and comparison with oxidation ponds system was conducted. In the post-constructed wetland, the removal of COD, TN and TP is 24%, 58.5% and 24.8% respectively. The treated effluent from the constructed wetland can meet the Chinese National Agricultural and Irrigation Standard. The comparison between pond–constructed wetland system and oxidation pond system shows that total nitrogen removal in a constructed wetland is better than that in an oxidation pond and the TP removal is inferior. A possible reason is the low dissolved oxygen concentration in the wetland. Constructed wetlands can restrain the growth of algae effectively, and can produce obvious ecological and economical benefits.

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Enhancing nitrogen removal efficiency in a dyestuff wastewater treatment plant with the IFFAS process: the pilot-scale and full-scale studies

Water Science & Technology ◽

10.2166/wst.2017.522 ◽

2017 ◽

Vol 77 (1) ◽

pp. 70-78 ◽

Cited By ~ 4

Author(s):

Yanjun Mao ◽

Xie Quan ◽

Huimin Zhao ◽

Yaobin Zhang ◽

Shuo Chen ◽

...

Keyword(s):

Wastewater Treatment ◽

Activated Sludge ◽

Removal Efficiency ◽

Nitrogen Removal ◽

Treatment Plant ◽

Oxygen Demand ◽

Pilot Scale ◽

Full Scale ◽

Nitrification And Denitrification ◽

Dyestuff Wastewater

Abstract The activated sludge (AS) process is widely applied in dyestuff wastewater treatment plants (WWTPs); however, the nitrogen removal efficiency is relatively low and the effluent does not meet the indirect discharge standards before being discharged into the industrial park's WWTP. Hence it is necessary to upgrade the WWTP with more advanced technologies. Moving bed biofilm processes with suspended carriers in an aerobic tank are promising methods due to enhanced nitrification and denitrification. Herein, a pilot-scale integrated free-floating biofilm and activated sludge (IFFAS) process was employed to investigate the feasibility of enhancing nitrogen removal efficiency at different hydraulic retention times (HRTs). The results showed that the effluent chemical oxygen demand (COD), ammonium nitrate (NH4+-N) and total nitrogen (TN) concentrations of the IFFAS process were significantly lower than those of the AS process, and could meet the indirect discharge standards. PCR-DGGE and FISH results indicated that more nitrifiers and denitrifiers co-existed in the IFFAS system, promoting simultaneous nitrification and denitrification. Based on the pilot results, the IFFAS process was used to upgrade the full-scale AS process, and the effluent COD, NH4+-N and TN of the IFFAS process were 91–291 mg/L, 10.6–28.7 mg/L and 18.9–48.6 mg/L, stably meeting the indirect discharge standards and demonstrating the advantages of IFFAS in dyestuff wastewater treatment.

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Poly Silk Peptide Film PH Sensor Based on Zero Current Potentiometry

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.450-451.554 ◽

2012 ◽

Vol 450-451 ◽

pp. 554-556

Author(s):

Ming Ming Ma ◽

Zhi Tong ◽

Yong Wen

Keyword(s):

Graphite Electrode ◽

Ph Sensor ◽

Reference Electrode ◽

Pencil Graphite Electrode ◽

Solution Ph ◽

Counter Electrodes ◽

System A ◽

Zero Current ◽

In Series ◽

Silk Peptide

A poly silk peptide film pH sensor has been developed using zero current potentiometry system. A poly silk peptide film coated pencil graphite electrode is connected in series between the working and counter electrodes of a potentiostat, and immersed in solution together with a reference electrode. When the solution pH varies, the resulting zero current potentiometry is linear with the values of the solution pH in the range of 1.81 to 11.58. This pH sensor shows high stability, accuracy, selectivity and reproduction.

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Upgrading of a small wastewater treatment plant in a cold climate region using a moving bed biofilm reactor (MBBR) system

Water Science & Technology ◽

10.2166/wst.2000.0027 ◽

2000 ◽

Vol 41 (1) ◽

pp. 177-185 ◽

Cited By ~ 23

Author(s):

G. Andreottola ◽

P. Foladori ◽

M. Ragazzi

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plant ◽

Treatment Plant ◽

Internal Surface ◽

Full Scale ◽

Biofilm Reactor ◽

Cold Climate ◽

Moving Bed Biofilm Reactor ◽

Moving Bed ◽

North East

The aim of this study was to evaluate the performance of a full-scale upgrading of an existing RBC wastewater treatment plant with a MBBR (Moving Bed Biofilm Reactor) system, installed in a tank previously used for sludge aerobic digestion. The full-scale plant is located in a mountain resort in the North-East of Italy. Due to the fact that the people varied during the year's seasons (2000 resident people and 2000 tourists) the RBC system was insufficient to meet the effluent standards. The MBBR applied system consists of the FLOCOR-RMP®plastic media with a specific surface area of about 160 m2/m3 (internal surface only). Nitrogen and carbon removal from wastewater was investigated over a 1-year period, with two different plant lay-outs: one-stage (only MBBR) and two stage system (MBBR and rotating biological contactors in series). The systems have been operated at low temperature (5–15°C). 50% of the MBBR volume (V=79 m3) was filled. The organic and ammonium loads were in the average 7.9 gCOD m−2 d−1 and 0.9 g NH4−N m−2 d−1. Typical carbon and nitrogen removals in MBBR at temperature lower than 8°C were respectively 73% and 72%.

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Model-based evaluation of a new upgrading concept for N-removal

Water Science & Technology ◽

10.2166/wst.2002.0104 ◽

2002 ◽

Vol 45 (6) ◽

pp. 169-176 ◽

Cited By ~ 25

Author(s):

S. Salem ◽

D. Berends ◽

J.J. Heijnen ◽

M.C.M. van Loosdrecht

Keyword(s):

Mathematical Modelling ◽

Scale Up ◽

Treatment Plant ◽

Ammonia Concentration ◽

Pilot Scale ◽

Full Scale ◽

Model Based ◽

N Removal ◽

Quantitative Basis ◽

Treatment Concepts

Mathematical modelling is considered a time and cost-saving tool for evaluation of new wastewater treatment concepts. Modelling can help to bridge the gap between lab and full-scale application. Bio-augmentation can be used to obtain nitrification in activated sludge systems with a limited aerobic sludge retention time. In the present study the potential for augmenting the endogenous nitrifying population is evaluated. Implementing a nitrification reactor in the sludge return line fed with sludge liquor with a high ammonia concentration leads to augmentation of the native nitrifying population. Since the behaviour of nitrifiers is relatively well known, a choice was made to evaluate this new concept mainly based on mathematical modelling. As an example an existing treatment plant (wwtp Walcheren, The Netherlands) that needed to be upgraded was used. A mathematical model, based on the TUDP model and implemented in AQUASIM was developed and used to evaluate the potential of this bioaugmentation in the return sludge line. A comparison was made between bio-augmentation and extending the existing aeration basins and anoxic tanks. The results of both modified systems were compared to give a quantitative basis for evaluation of benefits gained from such a system. If the plant is upgraded by conventional extension it needs an increase in volume of about 225%; using a bioaugmentation in the return sludge line the total volume of the tanks needs to be expanded by only 75% (including the side stream tanks). Based on the modelling results a decision was made to implement the bioaugmentation concept at full scale without further pilot scale testing, thereby strongly decreasing the scale-up period for this process.

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