Federal University of Lavras, Chemistry Department, 3037, 37200000 Lavras, Minas Gerais, Brazil.
Federal University of Lavras, Soil Science Department, 3037, 37200000 Lavras, Minas Gerais, Brazil; Vale Institute of Technology, 955 Boaventura da Silva Street, 66055090 Belém, Pará, Brazil.
Ecotoxicol Environ Saf. 2019 May 15;172:326-333. doi: 10.1016/j.ecoenv.2019.01.110. Epub 2019 Feb 2.
Excess heavy metal concentrations in mining areas is a worldwide problem due to their toxicity and persistence. Applying amendments to those areas is a cost-effective remediation technique that would aid revegetation efforts. The aim of this work was to study the ability of sewage sludge-derived biochar (SSB), wood charcoal powder (hereafter named wood biochar - WB), raw sewage sludge (SS), and their blending (WB/SS) to improve soil properties and to immobilize Cd, Pb, and Zn after their addition to heavy-metal contaminated soils from a Zn-mining area. Biochar was prepared from dried sewage sludge and a greenhouse experiment was set using different amendment doses (WB = 30 and 60 g kg, SS = 10 and 20 g kg). Addition of wood biochar and sewage sludge-derived biochar to soils led to increased leachate and soil pH. Biochar materials were responsible for the greatest reduction of Cd, Pb, and Zn bioavailability. The use of sewage sludge-derived biochar or the combination of sewage sludge with wood biochar in mining areas are potential alternatives for reusing and aggregating value to these locally available wastes, offering an opportunity to solve both soil remediation and waste disposal problems at once.
矿区重金属浓度过高是一个全球性问题，因为它们具有毒性和持久性。在这些地区应用改良剂是一种具有成本效益的修复技术，可以帮助植被恢复。本研究的目的是研究污水污泥衍生生物炭（SSB）、木粉生物炭（WB）、原始污水污泥（SS）及其混合物（WB/SS）在添加到锌矿区重金属污染土壤后，改善土壤性质和固定 Cd、Pb 和 Zn 的能力。生物炭是由干燥的污水污泥制备的，在温室中使用不同的改良剂剂量（WB = 30 和 60gkg，SS = 10 和 20gkg）进行了实验。向土壤中添加木粉生物炭和污水污泥衍生生物炭会导致浸出液和土壤 pH 值增加。生物炭材料对 Cd、Pb 和 Zn 的生物利用度降低最大。在矿区使用污水污泥衍生生物炭或污水污泥与木粉生物炭的组合是对这些本地可用废物进行再利用和增值的潜在选择，为同时解决土壤修复和废物处理问题提供了机会。
