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Accumulation of Toxic and Trace Metals in Agricultural Soil: A Review of Source and Chemistry in Ethiopia
Issue:
Volume 5, Issue 2, December 2021
Pages:
17-22
Received:
20 May 2021
Accepted:
1 July 2021
Published:
9 July 2021
Abstract: The main aim of this paper review is to know the extent of toxic and trace metals in some listed part Ethiopian farmland soil and its cause. Heavy metals are persistent in the agricultural soils (environments), they are non -termly and biological degradable. Among those toxic heavy metals, Pb, Cd, As, Hg, Cr, Co, Ni, Cu, Zn, Fe, Mn, are some of them. Every year’s large amount of industrial wastes, urban wastes, automobile emission, fertilizer, pesticide, wastewater irrigation and other agricultural activities are common in large agricultural farm land of Ethiopia. Those leads in to contamination of farmland with toxic heavy metals and other pollutants, The effect of those pollutants lower the quality of products finally they affect the health of consumers. According to different reports, in Ethiopia the farmland around cities and industry zone have accumulated large amount of toxic and trace heavy metals with compared to other farmlands. Mostly the concentration of those toxic metals were above the recommended limit set by different organization like FAO, WHO, EP and other. Therefore, the concerned body should be set different strategy and rule for agricultural activities, polluted factory effluents, gasses and solid wastes and other heavy metal source in order to protect the consumers from different heavy metals caused diseases.
Abstract: The main aim of this paper review is to know the extent of toxic and trace metals in some listed part Ethiopian farmland soil and its cause. Heavy metals are persistent in the agricultural soils (environments), they are non -termly and biological degradable. Among those toxic heavy metals, Pb, Cd, As, Hg, Cr, Co, Ni, Cu, Zn, Fe, Mn, are some of the...
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Decreasing COD Levels and Colors of Textile Industrial Waste with Electro-fenton Method
Ahmad Rosyid Priyadi,
Naniek Ratni Juliardi
Issue:
Volume 5, Issue 2, December 2021
Pages:
23-30
Received:
25 April 2021
Accepted:
11 May 2021
Published:
5 October 2021
Abstract: The wastewater from the coloring process in the textile industry threads and fabrics generally contains Azo compounds and organic pollutants which are difficult to decompose biologically and require a long time. The handling of these organic pollutants can be carried out with alternative advanced oxidation processes (AOPs) technology including the Electro-Fenton method. This study aims to obtain optimum operating conditions reduction of chemical oxygen demand (COD) and color in textile industry wastewater using the Electro-Fenton method. Processing is done by using the Electro-Fenton Method in batches with a time variation of 30.60,90,120,180 minutes. Using variations of electrical voltage of 6 volts with electrode distance is 2cm, 7 volts with electrode distance is 4cm, 8 volts with electrode distance is 6cm, variations of fenton doses based on the ratio of the molar ratio of H2O2:FeSO4 of (10:0.1), (10:0.2), (10:0,3). In addition to batching, this study also carried out a continuous Electro-Fenton experiment using electric voltage and electrode distance and the best contact time of the batch process. Based on the research, the processing efficiency of COD and Color in the textile industry wastes produced using the Electro-Fenton method of 94.1%, and 99.2%, respectively, on the ratio of the molar ratio of H2O2:FeSO4 10:0.1 with a voltage of 7 volt and 4 cm electrode distance in 180 minutes contact time and pH condition 4.
Abstract: The wastewater from the coloring process in the textile industry threads and fabrics generally contains Azo compounds and organic pollutants which are difficult to decompose biologically and require a long time. The handling of these organic pollutants can be carried out with alternative advanced oxidation processes (AOPs) technology including the ...
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Seasonal Variability and Wastewater Treatment Efficiency in Federal Capital Territory, Abuja
Samuel Oji Iheukwumere,
Philip Ogbonnaya Phil-Eze,
Kelechi Friday Nkwocha
Issue:
Volume 5, Issue 2, December 2021
Pages:
31-37
Received:
3 August 2021
Accepted:
16 August 2021
Published:
5 October 2021
Abstract: The study examined efficiency and seasonal variations in municipal wastewater treatment in Federal Capital Territory, Abuja. Wastewater treatment data from year 2015 to 2018 were analysed and compared with National Environmental Standard and Regulations Enforcement Agency permissible limit. The data were analysed to determine if seasonal variations exist in the performance of the wastewater treatment plant. The study was undertaken in the wastewater treatment plant located at Wupa, Abuja. The result obtained show that in 2015 a high reduction in biochemical oxygen demand (BOD) (84.6%) and chemical oxygen demand (COD) (85.4%) with excellent pH value (7.3pH, 90.8%) was achieved. In 2016, there was a significantly high level of treatment in Faecal Coliform (99.1%), BOD (93.4%), total suspended solids (TSS) (91.7%), COD (87.6%), and Ammonia (71.5%). In 2017, the level of treatment for BOD, COD and TSS were 97.2%, 95.7% and 95.4% respectively. While in 2018, removal efficiency of BOD was 95.2%, COD 91.6% and TSS 90.6%. The result also revealed that the observed values of the biochemical parameters are considerably lower when compared with the National Environmental Standards, Regulations and Enforcement Agency (NESREA) standards (i.e., p<0.05). The seasonal comparative result shows that the BOD total in dry season is significantly higher compared to the rainy season (t*=-3.553, p=0.001<0.05). The average COD in rainy season is slightly lower compared to that in dry season, and however, statistically insignificant (t*=-1.690, p=0.098). The TSS and pH values in rainy season are slightly and insignificantly lower compared with the values in the dry season. Continuous monitoring is recommended.
Abstract: The study examined efficiency and seasonal variations in municipal wastewater treatment in Federal Capital Territory, Abuja. Wastewater treatment data from year 2015 to 2018 were analysed and compared with National Environmental Standard and Regulations Enforcement Agency permissible limit. The data were analysed to determine if seasonal variations...
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Effects of Partial Saturation on Nitrogen Removal and Bacterial Community in Vertical-flow Constructed Wetlands
Khadija Kraiem,
Hamadi Kallali,
Rim Werheni Ammeri,
Bessadok Salma,
Naceur Jedidi
Issue:
Volume 5, Issue 2, December 2021
Pages:
38-44
Received:
2 July 2021
Accepted:
27 July 2021
Published:
19 October 2021
Abstract: The laboratory-scale pilot of constructed wetlands has been in operation for six months; (1) an unsaturated vertical flow constructed wetland (UVF-CW), this system was used to represent the classic vertical constructed wetlands, (2) a saturated vertical flow constructed wetland (SVF-CW), to evaluate the effects of the saturated condition on nitrogen removal and composition of the microbial community. The results showed that the saturation condition positiveley influenced the removal efficiencies of the nitrogen, the aeverage removal rate of the total kjeldahl nitrogen increased from 56% in unsaturated vertical flow constructed wetland (UVF-CW) to 63% in saturated vertical flow constructed wetland (SVF-CW). In addition, the microbial communities also was affected by the saturation condition, the relative abundances of nitrifying bacterium in UVF-CW are 13.8% (Nitrosomonas), 7.2% (Nitrosospira), 18.1% (Nitrospira) and 15.3% (Nitrobacter). In contrast, in SVF-CW, Nitrosomonas, Nitrosospira, Nitrospira and Nitrobacter only accounted for 6.8%, 5.6%, 7.4% and 10.6% respectively. However, the saturation condition seemed to increase denitrifying bacterium more than three times, in unsaturated vertical flow constructed wetland, only Pseudomonas (6.5%) and Paracoccus (4.85%) were detected, but in saturated vertical flow constructed wetland (SVF-CW), the abundance of Pseudomonas (13.08%) and Paracoccus (9.74%) were increased, and three other groups of denitrifying bacteria were also detected as Zoogloea (3.32%), Thauera (5.41%) and Thiobacillus (3%), due to the low availability of oxygen, it seems to be beneficial to denitrifying bacteria.
Abstract: The laboratory-scale pilot of constructed wetlands has been in operation for six months; (1) an unsaturated vertical flow constructed wetland (UVF-CW), this system was used to represent the classic vertical constructed wetlands, (2) a saturated vertical flow constructed wetland (SVF-CW), to evaluate the effects of the saturated condition on nitroge...
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