Department of Public Health, Dawo District Health Office, Southwest Shoa, Woliso, Ethiopia.
Department of Environmental Health Science and Technology, Institute of Health, Jimma University, P.O. Box 378, Jimma, Ethiopia.
J Environ Public Health. 2023 Jan 28;2023:7778240. doi: 10.1155/2023/7778240. eCollection 2023.
Most countries around the world have experienced water scarcity in recent decades as fresh water consumption has increased. However, untreated wastewater is routinely discharged into the environment, particularly in developing countries, where it causes widespread environmental and public health problems. The majority of wastewater treatment method publications are heavily focused on high-income country applications and, in most cases, cannot be transferred to low and middle-income countries. An experimental study was conducted to evaluate the performance efficiency of pilot-scale physicochemical and biological treatment methods for the treatment of household greywater in Jimma, Ethiopia. During the experiment, grab samples of greywater were taken from the combined treatment system's influent and effluent every 7 days for 5 weeks and analyzed within 24-48 hours. Temperature, DO, EC, turbidity, TDS, and pH were measured on-site, while BOD, COD, TSS, TP, TN PO -P, NO-N, NH-N, Cl, and FC were determined in the laboratory. During the five-week pilot-scale combined treatment system monitoring period, the combined experimental and control system's mean percentage reduction efficiencies were as follows: turbidity (97.2%, 92%), TSS (99.2%, 97.2%), BOD (94%, 57.4%), COD (91.6%, 54.7%), chloride (61%, 35%), TN (68.24, 42.7%), TP (71.6%, 38.7%), and FC (90%, 71.1%), respectively. Similarly, the combined experimental and control systems reduced PO -P (12.5 ± 3 mg/L), NO-N (4.5 ± 3 mg/L), and NH-N (10.19 ± 2.6 mg/L) to PO -P (3.5 ± 2.6 mg/L, 7.5 ± 1.6 mg/L), NO-N (0.8 ± 0.5, 3.6 ± 2.3 mg/L), and NH-N (7 ± 2.9 mg/L, 15.9 ± 3.9 mg/L), respectively. From the biofiltration and horizontal subsurface flow constructed wetland combined systems, the experimental combined technology emerged as the best performing greywater treatment system, exhibiting remarkably higher pollutant removal efficiencies. In conclusion, the combined biofiltration and horizontal subsurface flow constructed wetland treatment system can be the technology of choice in low-income countries, particularly those with tropical climates.
大多数国家在过去几十年中都经历了淡水资源短缺，因为淡水消耗量增加了。然而，未经处理的废水经常被排放到环境中，特别是在发展中国家，这造成了广泛的环境和公共卫生问题。大多数废水处理方法的出版物都非常关注高收入国家的应用，而且在大多数情况下，这些方法无法转移到低收入和中等收入国家。在埃塞俄比亚的吉姆马进行了一项实验研究，以评估中试规模物理化学和生物处理方法对家庭灰水的处理效果。在实验过程中，每隔 7 天从组合处理系统的进水和出水处采集一次灰水的随机样本，在 24-48 小时内进行分析。现场测量温度、DO、EC、浊度、TDS 和 pH 值，实验室测定 BOD、COD、TSS、TP、TN、PO4-P、NO3-N、NH3-N、Cl 和 FC。在五周的中试组合处理系统监测期间，组合实验和对照系统的平均百分比去除效率如下：浊度（97.2%，92%）、TSS（99.2%，97.2%）、BOD（94%，57.4%）、COD（91.6%，54.7%）、氯化物（61%，35%）、TN（68.24，42.7%）、TP（71.6%，38.7%）和 FC（90%，71.1%）。同样，组合实验和对照系统将 PO4-P（12.5±3mg/L）、NO3-N（4.5±3mg/L）和 NH3-N（10.19±2.6mg/L）降低至 PO4-P（3.5±2.6mg/L，7.5±1.6mg/L）、NO3-N（0.8±0.5，3.6±2.3mg/L）和 NH3-N（7±2.9mg/L，15.9±3.9mg/L）。从生物过滤和水平潜流人工湿地组合系统来看，实验组合技术是表现出更高污染物去除效率的最佳灰水处理系统。总之，组合生物过滤和水平潜流人工湿地处理系统可以成为低收入国家，特别是热带气候国家的首选技术。
