Evaluation of the Efficiency of Wastewater Treatment Plants in Taiz City and their Suitability for Irrigation

2020 ◽  
Vol 25 (1) ◽  
pp. 1-22
Author(s):  
Abdulatif A. Al-Munaifi ◽  
Soad A. Al-Sabban

Abstract A field study was carried out for influent and effluent wastewater from Two treatment plants in Taiz city. The aim of the study is to evaluate and increase the efficiency of the treatment plants in Al-Buriahy and Nadfood factories (Al-Qurf), in order to ensure the safe and suitable use of wastewater for irrigation. Four samples of sewage were collected from influent and effluent of different locations within the areas of Al-Qurf, Al-Hawjlah, Hidran Al-Dabab and Al-Buraihy. The results of the chemical analysis showed that the samples of the partially treated wastewater compared with the untreated wastewater were higher in total dissolved solids. The values of the trace elements remained at the level of the sewage influent before and after the treatment plant in Al-Buraihy, the level of treatment did not decrease the concentration of a number of these elements. The results of the study indicate that the concentration of Biochemical Oxygen Demand (BOD5) for effluent wastewater from the treatment plants recorded a significant decrease in their values. In contrast the results were close in the concentration of the BOD5 influent from the treatment plant in Al-Buraihy with the BOD5 concentration effluent from the treatment plant in the Nadfood has, reached 457mg/l, because the influent of the sewage from the industrial processes in the treatment plant of the Nadfood was too high, reaching an average of 7791 mg / l compared with 553 mg / l in the municipal influent sewage at the treatment plant in Al-Buraihy. The results of bacteriological analyses showed that the treated wastewater recorded a significant reduction in the number of fecal coliform compared with the number of fecal coliform at influent from treatment plant at Al-Buraihy area.These indications for treatment in wastewater stabilization ponds in Al-Buraihy, and treatment  plant for industrial wastewater, that include the aeration and sedimentation units in Al-Qurf Nadfood factories, indicate that the degree of treatment is below the required level and still exceeds the limit allowed for irrigation purposes according to Yemeni and International standards. This suggests an action of rehabilitation of existing sewerage system, completion of the sewerage network and the establishment of the new treatment plant by using stabilization ponds with floating surface aerator in the facultative ponds at north of Taiz City. In addition, increase the efficiency of the current treatment plant by division of wastewater stabilization ponds in Al-Buraihy, into anaerobic, facultative and maturation ponds, providing each pond with two devices/tools to measure the flows, and the  establishment of the new treatment plant at the Nadfood factories. It should consist of screening, oil /fat removal, primary and secondary clarifiers, high rate trickling filters (1st and 2nd stage), sludge digester, sand drying beds, and chlorination. Keywords: Taiz city, sewage, biochemical oxygen demand, fecal coliform,treatment plant, efficiency, municipal, industrial.

2018 ◽  
Vol 14 (27) ◽  
pp. 193
Author(s):  
Kamal Ait Ouhamchich ◽  
Abdelkrim Arioua ◽  
Mustapha Lbayny ◽  
Ismail Karaoui ◽  
Khalid El Habbari ◽  
...  

The wastewater purification is a complicated and costlier operation if it not well chosen. Contrariwise, it could be simple and cheaper if the treatment system respect the environmental conditions and under international standards. To purify its wastewater, Boujaâd City chose to use the natural lagooning system. To verify the ability of this system, our study focuses on assessing the performances of this system to purify Boujaad city wastewater. For this reason, this study is based on the physicochemical monitoring of raw and purified water, both spatially and temporally, to detect and determine the percentage of pollution abatement in this wastewater treatment plant. According to the results, the quality of wastewater treatment plant rejection is conforming to the national and international standards. Here, the biochemical oxygen demand (BOD), chemical oxygen demand (COD), and suspended solids (SS) parameters reached 69%, 66%, and 86% respectively. The results obtained show that the purification operation in Boujaad wastewater treatment plant was adequate.


2018 ◽  
Vol 31 ◽  
pp. 05009
Author(s):  
Ihsan Wira S ◽  
Sunarsih Sunarsih

Pollution is a man-made phenomenon. Some pollutants which discharged directly to the environment could create serious pollution problems. Untreated wastewater will cause contamination and even pollution on the water body. Biological Oxygen Demand (BOD) is the amount of oxygen required for the oxidation by bacteria. The higher the BOD concentration, the greater the organic matter would be. The purpose of this study was to predict the value of BOD contained in wastewater. Mathematical modeling methods were chosen in this study to depict and predict the BOD values contained in facultative wastewater stabilization ponds. Measurements of sampling data were carried out to validate the model. The results of this study indicated that a mathematical approach can be applied to predict the BOD contained in the facultative wastewater stabilization ponds. The model was validated using Absolute Means Error with 10% tolerance limit, and AME for model was 7.38% (< 10%), so the model is valid. Furthermore, a mathematical approach can also be applied to illustrate and predict the contents of wastewater.


Author(s):  
Hafiz Qasim Ali ◽  
Amir Farooq ◽  
Amir Farooq ◽  
Mohammad Laeeque Ahmed ◽  
Muhammad Akhtar

Wastewater management is one of the biggest challenges in the world due to increase in population and industrialization. In Faisalabad (FSD), wastewater treatment is being done through Wastewater Stabilization Ponds (WSPs) at Chokera, which is one of the most economical methods of Wastewater Treatment (WWT). Various parameters were examined to check wastewater treatment efficiency of the ponds under diverse climatic conditions. These included Biochemical Oxygen Demand (BOD), pH, Chemical Oxygen Demand (COD), Turbidity, Copper, Total Solids (TS), Total Dissolved Solids (TDS) and Lead. Six locations which were selected for monitoring treatment efficiency, included inlet and outlet of treatment plant, influent of anaerobic ponds, effluent of anaerobic ponds, effluent of facultative ponds, and Pharang drain before and after blending with treated sewage. The testing was performed in two seasons (i.e. Winter 2015 and Summer 2016) in Environmental Engineering Laboratory, Department of Civil Engineering, The University of Lahore, Pakistan. BOD5 removal efficiency of the treatment plant was found 30.08% in winter and 51.74% in summer against designed value of 90% removal. Most of the parameters of the effluent were not meeting the Punjab Environmental Quality Standards (PEQS). The reasons of low efficiency are; variation in climatic conditions (i.e. less solar heat intensity, wind speed and ceased microbial activity in winter), lack of funds by government, increased population, mixing of industrial sewage with domestic sewage and less attention being paid to maintain the performance of Ponds. The study was carried out to assess and compare the efficiency of treatment plant with PEQS in two climatic conditions.


1987 ◽  
Vol 19 (12) ◽  
pp. 265-271
Author(s):  
P. R. Thomas ◽  
H. O. Phelps

The investigation was based on two facultative stabilization ponds initially designed to operate in parallel, and now receive wastewater in excess of their capacities from a fast expanding housing estate in the Caribbean Island of Trinidad. Because of the deterioration of the effluent quality relative to acceptable standards, an attempt was made to upgrade the ponds using water hyacinths at the early stages. However, from the results, it was clear that the introduction of water hyacinths in the test pond did not lead to any substantial improvement in the effluent because of the high loading on the pond. Therefore the ponds were modified to operate in series with surface aerators installed in the first pond. Initially, the effluent quality was monitored in terms of total suspended solids, volatile suspended solids, biochemical oxygen demand, faecal coliform bacteria, pH and dissolved oxygen with aeration in the first pond and no aquatic plants in the second pond. Although there was a significant improvement in the effluent quality, the values remained above the standards. As a result, water hyacinths were introduced in the second pond and the effluent quality monitored together with aeration in the first pond. The effluent quality improved with total suspended solids and biochemical oxygen demand values both as low as 10 mg/l in certain months, but additional treatment was needed to reduce faecal conforms.


2011 ◽  
Vol 1 (3) ◽  
pp. 179-184 ◽  
Author(s):  
Beenish Saba ◽  
Tariq Mahmood ◽  
Bushra Zaman ◽  
Imran Hashmi

Reclaimed wastewater reuse for irrigation to crop plants is evaluated in a laboratory-scale experiment to assess growth and water saving potential from natural resources. A prototype laboratory-scale treatment plant was established for this purpose with suspended and attached growth configurations. Chakwal wheat variety was selected to examine growth parameters. The removal of chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) were evaluated to check the quality of treated water. It was found that a suspended growth sequencing batch bioreactor (SGSBBR) achieved 97% ± 2 removal efficiency over a 4 h hydraulic retention time (HRT). For an attached growth sequencing batch bioreactor (AGSBBR) results showed 98% ± 2 removal efficiencies with polyurethane. TN and TP removal efficiency was 58.7 ± 3% and 64 ± 4.8% in SGSBBR, 53 ± 0.17% and 67 ± 2.7% in polyurethane. AGSBBR enhanced performance with AGSBBR may be due to enforced anoxic/aerobic conditions in the inner layers of biofilm formed on biocarriers which facilitate the required metabolic conditions for treating high strength wastewater. Plant growth was visibly greater in SGSBBR treated wastewater than AGSBBR because of less nutrient removal.


2013 ◽  
Vol 47 (2) ◽  
pp. 841-849 ◽  
Author(s):  
Mark A. Jordan ◽  
David T. Welsh ◽  
Richard John ◽  
Kylie Catterall ◽  
Peter R. Teasdale

2017 ◽  
Vol 76 (3) ◽  
pp. 633-641 ◽  
Author(s):  
Erwan Carré ◽  
Jean Pérot ◽  
Vincent Jauzein ◽  
Liming Lin ◽  
Miguel Lopez-Ferber

The aim of this study is to investigate the potential of ultraviolet/visible (UV/Vis) spectrometry as a complementary method for routine monitoring of reclaimed water production. Robustness of the models and compliance of their sensitivity with current quality limits are investigated. The following indicators are studied: total suspended solids (TSS), turbidity, chemical oxygen demand (COD) and nitrate. Partial least squares regression (PLSR) is used to find linear correlations between absorbances and indicators of interest. Artificial samples are made by simulating a sludge leak on the wastewater treatment plant and added to the original dataset, then divided into calibration and prediction datasets. The models are built on the calibration set, and then tested on the prediction set. The best models are developed with: PLSR for COD (Rpred2 = 0.80), TSS (Rpred2 = 0.86) and turbidity (Rpred2 = 0.96), and with a simple linear regression from absorbance at 208 nm (Rpred2 = 0.95) for nitrate concentration. The input of artificial data significantly enhances the robustness of the models. The sensitivity of the UV/Vis spectrometry monitoring system developed is compatible with quality requirements of reclaimed water production processes.


2021 ◽  
Author(s):  
Semase Matseleng ◽  
Ozekeke Ogbeide ◽  
Patricks' Otomo Voua

Abstract Wastewater treatment facilities in developing countries like South Africa are major sources of contaminants via effluent into the environment, which could portend high toxicity risks for non-target flora and fauna. To this end, a study was conducted to determine the ecotoxicological responses of selected organism to treated and untreated wastewater from the wastewater treatment plants in an industrial town. The snail Helix pomatia was exposed to OECD artificial soil spiked with untreated or treated wastewater at the following concentrations: 0, 25, 50, 75, 100%. The ecotoxicological responses of Helix pomatia to wastewater were determined by assessing the biomass, survival, reproduction and biomarker responses (Catalase ‒ CAT and Acetylcholinesterase ‒ AChE activities). The overall results showed significant effects on the survival, reproduction and biomass of H. pomatia. Similar results were observed for juvenile emergence. An EC50 of 5.751% for egg production and an EC50 of 6.233% for juvenile emergence were determined in the untreated wastewater. Such indices could not be computed for the treated wastewater, indicating a decreased in toxicity between the untreated and the treated samples. For both the AChE and CAT activities, there was no statistical difference between treated and untreated wastewater treatments. The results from this study highlight the toxic effects of untreated wastewater and indicate that treated wastewater (effluent) released from the wastewater treatment plant in Phuthaditjhaba remains suitable for invertebrate fauna such as H. pomatia.


Sign in / Sign up

Export Citation Format

Share Document