scholarly journals CONTAMINATION OF THE ROOT VEGETABLES WASH WATER AND ITS TREATMENT EFFICIENCY

2018 ◽  
Author(s):  
Midona DAPKIENĖ ◽  
Nomeda SABIENĖ ◽  
Algirdas RADZEVIČIUS
Keyword(s):  
Wastewater Treatment ◽  
Total Nitrogen ◽  
Total Phosphorus ◽  
Constructed Wetland ◽  
Suspended Solids ◽  
Oxygen Demand ◽  
Wash Water ◽  
Treatment System ◽  
Wastewater Treatment System ◽  
Root Vegetables

Growing volume of washed vegetables in Europe and Lithuania means that more drinking water is consumed and more wastewater is produced. Farmers, who engage in washing vegetables, face the problems of wastewater treatment, wastewater storage and utilization. Wastewater released to the environment from their farms would meet hygiene and environmental protection criteria. The aim of the study was to assess the contamination of the root vegetable wash water and to evaluate the possiblity of cleaning of wastewater in the land-based treatment system consisting of one constructed wetland and two biological ponds. The contamination of wastewater, produced by washed root vegetables, in Lithuanian farms was measured according to suspended solids (SS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen and total phosphorus. Pollution of the wash water and wastewater was evaluated comparing the mean values with legislative limit values and with typical sewage contamination values. In all farms wastewater of initial root vegetables washing was treated in settling basins. Wastewater of one carrots washing farm was treated in the land-based wastewater treatment system consisting of surface flow constructed wetland and two biological ponds. Efficiency of the wastewater treatment in this system was according to suspended solids 90%, BOD7 – 97%, CODCr – 92%, total nitrogen – 98% , total phosphorus – 97%. The result shows, that the natural wastewater treatment system is suitable for farms, that wash and produce vegetables, but before releasing wastewater to the environment, it has to be settled.

Removal efficiency of the constructed wetland wastewater treatment system at Bainikeng, Shenzhen

1995 ◽  
Vol 32 (3) ◽  
pp. 31-40 ◽  
Author(s):  
Yang Yang ◽  
Zhencheng Xu ◽  
Kangping Hu ◽  
Junsan Wang ◽  
Guizhi Wang
Keyword(s):  
Wastewater Treatment ◽  
Removal Efficiency ◽  
Constructed Wetland ◽  
Suspended Solids ◽  
Oxygen Demand ◽  
Design Flow ◽  
Treatment System ◽  
Wastewater Treatment System ◽  
Tennessee Valley ◽  
Wetland System

In this paper, three years study on a constructed wetland wastewater treatment system at Bainikeng, Shenzhen, is reviewed and summarized. The wetland system under study occupies an area of 8400m2, with a design flow of 3100 m3 per day. The study was conducted to understand removal efficiencies of constructed wetland systems for municipal wastewaters from small or medium scale towns in the sub-tropics. Such parameters as biological oxygen demand, chemical oxygen demand, suspended solids, total nitrogen, and total phosphorus in the influent and effluent of the wetland system are examined, and their removal rates are determined. It is shown that the system is very effective in removing organic pollutants and suspended solids and its removal efficiency is much similar to those of the constructed wetlands at Tennessee Valley Authority (TVA) (Choate et al., 1990) while better than those of conventional secondary biochemical treatments.

scholarly journals The Efficiency and Reliability of Pollutant Removal in a Hybrid Constructed Wetland with Common Reed, Manna Grass, and Virginia Mallow

Water ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1445 ◽  
Author(s):  
Michał Marzec ◽  
Krzysztof Jóźwiakowski ◽  
Anna Dębska ◽  
Magdalena Gizińska-Górna ◽  
Aneta Pytka-Woszczyło ◽  
...  
Keyword(s):  
Total Nitrogen ◽  
Total Phosphorus ◽  
Constructed Wetland ◽  
Suspended Solids ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Total Suspended Solids ◽  
Common Reed ◽  
Pollutant Removal ◽  
Limit Values

In this paper, the pollutant removal efficiency and the reliability of a vertical and horizontal flow hybrid constructed wetland (CW) planted with common reed, manna grass, and Virginia mallow were analyzed. The wastewater treatment plant, located in south-eastern Poland, treated domestic sewage at an average flow rate of 2.5 m3/d. The tests were carried out during five years of its operation (2014–2018). The following parameters were measured: biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total suspended solids, total nitrogen, and total phosphorus. The results showed that more than 95% of BOD5, COD, and total phosphorus was removed in the tested CW system. The average effectiveness of removal of total suspended solids and total nitrogen exceeded 86%. A reliability analysis performed using the Weibull probability model showed that the removal reliability in the tested CW was very high for BOD5, COD, total suspended solids, and total phosphorus (100%). The probability that the total nitrogen concentration in the treated effluents would reach the limit value (30 mg/L) established for effluents discharged from a treatment plant of less than 2000 PE (population equivalent) to standing waters was 94%. The values of all the pollution indicators in wastewater discharged to the receiver were significantly lower than the limit values required in Poland. The investigated hybrid CW system with common reed, manna grass, and Virginia mallow guaranteed stable low values of BOD5, COD, total suspended solids, and total phosphorus in the treated wastewater, which meant it was highly likely to be positively evaluated in case of an inspection.

scholarly journals Effect of hydraulic retention time on chemical oxygen demand and total nitrogen removal in intermittently aerated constructed wetlands

2020 ◽  
Vol 15 (3) ◽  
pp. 1 ◽  
Author(s):  
Isabela Pires da Silva ◽  
Gabriela Barbosa da Costa ◽  
João Gabriel Thomaz Queluz ◽  
Marcelo Loureiro Garcia
Keyword(s):  
Chemical Oxygen Demand ◽  
Constructed Wetlands ◽  
Total Nitrogen ◽  
Total Phosphorus ◽  
Constructed Wetland ◽  
Retention Time ◽  
Hydraulic Retention Time ◽  
Subsurface Flow ◽  
Oxygen Demand ◽  
Intermittent Aeration

   This study evaluated the effect of hydraulic retention time on chemical oxygen demand (COD) and total nitrogen (TN) removal in an intermittently aerated constructed wetlands. Two horizontal subsurface-flow constructed wetlands were used: one without aeration and the other aerated intermittently (1 hour with aeration/7 hours without aeration). Both systems were evaluated treating domestic wastewater produced synthetically. The flow rate into the two CWs was 8.6 L day-1 having a hydraulic retention time of 3 days. The results show that the intermittently aerated constructed wetland were highly efficient in removing COD (98.25%), TN (83.60%) and total phosphorus (78.10%), while the non-aerated constructed wetland showed lower efficiencies in the removal of COD (93.89%), TN (48.60%) and total phosphorus (58.66). These results indicate, therefore, that intermittent aeration allows the simultaneous occurrence of nitrification and denitrification processes, improving the removal of TN in horizontal subsurface-flow constructed wetlands. In addition, the use of intermittent aeration also improves the performance of constructed wetlands in removing COD and total phosphorus.

scholarly journals Process performance and reuse potential of a decentralized wastewater treatment system

2019 ◽  
Vol 80 (11) ◽  
pp. 2079-2090 ◽  
Author(s):  
Rajiv Ranjan ◽  
Lokendra Kumar ◽  
P. C. Sabumon
Keyword(s):  
Wastewater Treatment ◽  
Growth Parameters ◽  
Oxygen Demand ◽  
Primary Treatment ◽  
Treatment System ◽  
Tagetes Erecta ◽  
Wastewater Treatment System ◽  
Decentralized Wastewater Treatment ◽  
Treated Effluent ◽  
Decentralized Wastewater Treatment System

Abstract The paper describes briefly the process performance and the reuse potential of a laboratory scale wastewater treatment system. The treatment involves enhanced primary treatment of Vellore Institute of Technology (VIT) campus sewage using ferric chloride as a coagulant, anaerobic digestion of coagulated organics, and biofilm aerobic process. The treated effluent after disinfection (using sunlight and chlorine) was used for irrigation of Tagetes erecta (marigold) plants and the plant growth parameters were evaluated for a life span of 3 months. In the primary treatment, an optimum ferric chloride dose of 30 mg/L could remove turbidity, chemical oxygen demand (COD), biochemical oxygen demand (BOD), and bacterial count (Escherichia coli) of 69%, 60%, 77%, and 55%, respectively. The coagulated organics could digest in a 25 L anaerobic reactor effectively with methane content in biogas varied between 50 and 60% and enhanced volatile suspended solids (VSS) reduction up to 70%. Sunlight based photo-oxidation followed chlorine disinfection saved 50% of the chlorine dose required for disinfection and treated effluent was fit for reuse. The results of growth parameters for Tagetes erecta plants indicate that anaerobically digested sludge is an excellent soil conditioner cum nutrient supplier. The results of this study exhibit a promising reuse potential of a decentralized wastewater treatment system and needs to be promoted for field scale applications.

Reed beds: constructed wetlands for municipal wastewater treatment plant sludge dewatering

2001 ◽  
Vol 44 (11-12) ◽  
pp. 393-398 ◽  
Author(s):  
J.S. Begg ◽  
R.L. Lavigne ◽  
P.L.M. Veneman
Keyword(s):  
Wastewater Treatment ◽  
Total Phosphorus ◽  
Biochemical Oxygen Demand ◽  
Suspended Solids ◽  
Oxygen Demand ◽  
Total Suspended Solids ◽  
Sludge Dewatering ◽  
Sludge Treatment ◽  
Reed Beds ◽  
Reed Bed

Reed beds are an alternative technology wastewater treatment system that mimic the biogeochemical processes inherent in natural wetlands. The purpose of this project was to determine the effectiveness of a reed bed sludge treatment system (RBSTS) in southern New England after a six-year period of operation by examining the concentrations of selected metals in the reed bed sludge biomass and by determining the fate of solids and selected nutrients. Parameters assessed in both the reed bed influent and effluent: total suspended solids, biochemical oxygen demand, nitrate-nitrogen and total phosphorus. In addition, the following metals were studied in the reed bed influent, effluent and Phragmites plant tissue and the sludge core biomass: boron, cadmium, chromium, copper, iron, lead, manganese, molybdenum, nickel, and zinc. The removal efficiencies for sludge dewatering, total suspended solids and biochemical oxygen demand were all over 90%. Nitrate and total phosphorus removal rates were 90% and 80% respectively. Overall metals removal efficient was 87%. Copper was the only metal in the sludge biomass that exceeded the standards set by the Massachusetts Department of Environmental Protection for land disposal of sludge. The highest metal concentrations, for the most part, tended to be in the lower tier of the sludge profile. The exception was boron, which was more concentrated in the middle tier of the sludge profile. The data and results presented in this paper support the notion that reed bed sludge treatment systems and the use of reed beds provide an efficient and cost effective alternative for municipal sludge treatment.

scholarly journals Efficiency of Sewage Treatment Plants in the Sequential Batch Reactor

2018 ◽  
Vol 28 (3) ◽  
pp. 121-131 ◽  
Author(s):  
Anita Jakubaszek ◽  
Artur Stadnik
Keyword(s):  
Wastewater Treatment ◽  
Total Nitrogen ◽  
Total Phosphorus ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Batch Reactor ◽  
Sewage Treatment ◽  
Total Suspended Solids ◽  
Sewage Treatment Plants ◽  
Sequential Batch Reactor

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.

scholarly journals Economic feasibility for wastewater treatment system composed of wetlands for the wastewater reuse: a case study

2020 ◽  
Vol 12 (2) ◽  
Author(s):  
Robson Muniz McMahon Waite ◽  
Eduardo Gomes Salgado ◽  
Dirlane De Fátima do Carmo
Keyword(s):  
Wastewater Treatment ◽  
Constructed Wetland ◽  
Subsurface Flow ◽  
Treatment System ◽  
Rate Of Return ◽  
Internal Rate Of Return ◽  
Wastewater Treatment System ◽  
Internal Rate ◽  
Financial Feasibility ◽  
Subsurface Flow Constructed Wetland

Water is an asset that is becoming scarce and its reuse is an alternative to preserve it. Social and environmental feasibility motivate the adoption of reuse, but the financial factor can be limited to its use. The objective of this study was to evaluate the economic and financial feasibility for the investment in a domestic wastewater treatment system in which the constructed wetlands could be used aiming at the reuse for irrigation. Instruments such as the minimum attractiveness rate, discounted payback, the internal rate of return and the profitability index were used. The treatment system composed of an equalization tank, a septic tank, horizontal subsurface flow constructed wetland, subsurface flow constructed wetland, and a maturation pond comprising 52 m², demonstrating that it is able to meet the criteria required for reuse. The organic load affluent to the system was projected to 220 mg L-1 at a flow rate of 600 L day-1 of sewage, obtaining removal efficiency above 98% for all parameters, except nitrogen and phosphorus. In the analysis of economic and financial feasibility, it was found that the internal rate of return found for the cash flow considered was 98% and the profitability index according to the present value was 3.28. It was found that the total employed would be recovered in up to two years. With the use of the system, 180 m³ of water would be saved annually, reducing the pressure on the public supply system, in addition to the sewage treatment and the scenic beauty provided by wetlands. Therefore, the system is not limited only to economic gains, but also to social and environmental gains.

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