National Research Institute for Forestry, Agriculture and Animal Production, Av. Biodiversidad 2470, Tepatitlán de Morelos 47600, Jalisco, Mexico.
National Research Institute for Forestry, Agriculture and Animal Production, Km 6 Entronque Carretera Internacional Mexico-Nogales, Santiago Ixcuintla 63300, Nayarit, Mexico.
Int J Environ Res Public Health. 2018 May 21;15(5):1031. doi: 10.3390/ijerph15051031.
Pollutants from pig farms in Mexico have caused problems in many surface water reservoirs. Growing concern has driven the search for low-cost wastewater treatment solutions. The objective of this research was to evaluate the potential of an in-series constructed wetland to remove nutrients from wastewater from a pig farm. The wetland system had a horizontal flow that consisted of three cells, the first a surface water wetland, the second a sedimentation cell, and the third a subsurface flow wetland. The vegetation used was sp. and sp. A mix of soil with red volcanic rock (10⁻30 mm diameter) and yellow sand (2⁻8 mm diameter) was used as a substrate for the vegetation. The experiments were carried out in duplicate. Water samples were collected at the inflow and outflow of the cells. Two hydraulic retention times (HRT) (5 and 10 days) and three treatments were evaluated: 400, 800, and 1200 mg·L of chemical oxygen demand (COD) concentration. Data was collected in situ for temperature, pH, dissolved oxygen (DO), electrical conductivity (EC), and total dissolved solids (TDS). COD, total Kjeldahl nitrogen (TKN), ammonia nitrogen (NH₃⁻N), and total phosphorous (TP) were analyzed in the laboratory. The results showed that the in-series constructed wetland is a feasible system for nutrient pollutant removal, with COD removal efficiency of 76% and 80% mg·L for a 5- and 10-day HRT, respectively. The removal efficiency for TKN, NH₃⁻N, and TP reached about 70% with a 5-day HRT, while a removal of 85% was obtained with a 10-day HRT. The wetland reached the maximum removal efficiency with a 10-day HRT and an inflow load of 400 mg·L of organic matter. The results indicate that HRT positively affects removal efficiency of COD and TDS. On the other hand, the HRT was not the determining factor for TP removal. Treatment one, with an initial COD concentration of 400 mg·L, had the highest removal of the assessed pollutants, allowing for the use of water for irrigation according to Mexican regulatory standards (NOM-001). The water quality resulting from treatments two and three (T2 = 800 mg·L of COD and T3 = 1200 mg·L of COD) did not comply with minimal requirements for irrigation water.
墨西哥养猪场的污染物已对许多地表水水库造成了问题。日益增长的担忧促使人们寻找低成本的废水处理解决方案。本研究的目的是评估串联式人工湿地从养猪场废水中去除养分的潜力。湿地系统采用水平流，由三个单元组成，第一个是地表水湿地，第二个是沉淀单元，第三个是潜流湿地。使用的植物是 和 。土壤与红火山岩（10-30 毫米直径）和黄沙（2-8 毫米直径）的混合物用作植物的基质。实验进行了两次重复。在单元的入口和出口处采集水样。评估了两个水力停留时间（HRT）（5 天和 10 天）和三种处理方法：化学需氧量（COD）浓度为 400、800 和 1200 mg·L。现场收集温度、pH 值、溶解氧（DO）、电导率（EC）和总溶解固体（TDS）的数据。在实验室中分析 COD、总凯氏氮（TKN）、氨氮（NH₃⁻N）和总磷（TP）。结果表明，串联式人工湿地是一种可行的养分污染物去除系统，5 天和 10 天 HRT 时 COD 去除效率分别为 76%和 80%。5 天 HRT 时，TKN、NH₃⁻N 和 TP 的去除效率约为 70%，而 10 天 HRT 时则达到 85%。湿地在 10 天 HRT 和 400 mg·L 有机负荷的流入条件下达到最大去除效率。结果表明，HRT 对 COD 和 TDS 的去除效率有积极影响。另一方面，HRT 不是 TP 去除的决定因素。处理 1 的初始 COD 浓度为 400 mg·L，对评估的污染物去除率最高，允许根据墨西哥监管标准（NOM-001）将水用于灌溉。处理 2（T2=800 mg·L COD）和处理 3（T3=1200 mg·L COD）的水质不符合灌溉水的最低要求。
