Modeling nitrogen removal in water hyacinth ponds receiving effluent from waste stabilization ponds

In this study it was demonstrated that when water hyacinth ponds (WHPs) are used for polishing the effluent from waste stabilization ponds (WSPs), suspended solids (mostly algal particles) are efficiently separated, which also resulted in the reduction of insoluble forms of COD and nutrients. The high pH of the WSPs effluent was easily adjusted to 6-7 as it passed through the WHPs. However, the use of water hyacinth rapidly reduced dissolved oxygen at the first cell to less than three mg/L or very frequently to a level of anaerobic state. Reduction of suspended solids at the WHPs mainly depends on the detention time and pH. An empirical separation model incorporating the detention time and pH dependence was developed.

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Nitrogen removal in attached growth waste stabilization ponds of wastewater from a rubber factory

Water Science & Technology ◽

10.2166/wst.1999.0011 ◽

1999 ◽

Vol 40 (1) ◽

pp. 45-52

Author(s):

A. Rakkoed ◽

S. Danteravanich ◽

U. Puetpaiboon

Keyword(s):

Nitrogen Removal ◽

Waste Treatment ◽

Pond Water ◽

Anaerobic Treatment ◽

Waste Stabilization Ponds ◽

Attached Growth ◽

Stabilization Ponds ◽

Waste Stabilization ◽

Removal Efficiencies ◽

Laboratory Waste

Nitrogen removal from wastewater from rubber factories using attached-growth waste stabilization ponds (AGWSP) was evaluated. Usually, wastewaters generated from rubber factories such as concentrated latex factories and rubber sheet factories contain a high amount of nitrogen originating from natural rubber and ammonia compounds added in the production processes. From an investigation of 3 rubber factories at Songkhla, Thailand, average concentrations of TKN, NH3-N and Org-N in raw factory wastewater were found to be 889, 578 and 311 mg/l respectively. Two series of laboratory waste treatment ponds, waste stabilization ponds (WSP) and attached-growth waste stabilization ponds were investigated to compare the efficiency of nitrogen removal from wastewater from a concentrated latex factory. The wastewater fed to the experimental units was collected from the effluent of the anaerobic treatment pond at the factory. The experiments were conducted with hydraulic retention times (HRT) of 40 and 20 days. Another experiment run with an HRT of 40 days together with 50% recirculating of effluent was also conducted. Finally, an experiment run at an HRT of 4 days was carried out in order to observe the effect of shock loading. The results revealed that TKN, NH3-N and BOD5 removal efficiencies in AGWSP were higher than in control ponds (WSP). Increased removal efficiencies were achieved which resulted from an increase in biomass on media in the pond water.

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Evaluation of nitrogen reduction in water hyacinth ponds integrated with waste stabilization ponds

Desalination ◽

10.1016/j.desal.2008.11.013 ◽

2009 ◽

Vol 249 (2) ◽

pp. 528-534 ◽

Cited By ~ 12

Author(s):

Qitao Yi ◽

Youngchul Kim ◽

Masafumi Tateda

Keyword(s):

Water Hyacinth ◽

Waste Stabilization Ponds ◽

Nitrogen Reduction ◽

Stabilization Ponds ◽

Waste Stabilization

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Nitrogen removal in baffled waste stabilization ponds

Water Science & Technology ◽

10.2166/wst.1996.0136 ◽

1996 ◽

Vol 33 (7) ◽

pp. 173-181 ◽

Cited By ~ 4

Author(s):

S. Muttamara ◽

U. Puetpaiboon

Keyword(s):

Removal Efficiency ◽

Nitrogen Removal ◽

Plug Flow ◽

Specific Area ◽

Pilot Scale ◽

Bacterial Biofilm ◽

Waste Stabilization Ponds ◽

Stabilization Ponds ◽

N Removal ◽

Waste Stabilization

This study evaluated nitrogen removal in Baffled Waste Stabilization Ponds (BWSPs) comprising laboratory and pilot-scale ponds with different number of baffles. The aim was to promote the waste stabilization pond practice for wastewater treatment in tropical countries by increasing nitrogen and organic carbon removal efficiency or reducing the land area requirement through the use of baffles which increased the biofilm biomass concentrations. The experiments started with a tracer study to find out the hydraulic characteristics of each pond. It was shown that the dispersion number decreased with increasing flow length and number of baffles which indicated more plug flow conditions. The deviation of actual HRT from theoretical HRT was computed and the flow pattern suggested the existence of an optimum spacing of baffles in BWSP units. The investigations further revealed that more than 65% TN and 90% NH3-N removal efficiencies were achieved at HRT of 5 days in a 6 baffled pond, which corresponds to the specific area of 34.88 m2m3. TN and NH3-N removal increased with increasing number of baffles in the BWSP units. Combined algal/bacterial biofilm grown on the baffles immersed in the ponds showed potential for increasing the extent of nitrification. COD removal increased with higher number of baffles with its maximum removal efficiency at 6 baffles. Compared with normal WSP, BWSP gave higher TN, NH3-N, COD and BOD5 removal efficiency. The effluent SS concentrations from the laboratory-scale 6 baffled pond were less than 20 mg/L at HRT of 3 days or more.

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