School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China.
Bioresour Technol. 2010 Jul;101(14):5222-8. doi: 10.1016/j.biortech.2010.02.052. Epub 2010 Mar 4.
Conversion of waste products into biochar (BC) is being considered as one of several waste disposal and recycling options. In this study, we produced BC from dairy manures by heating at low temperatures (500 degrees C) and under abundant air condition. The resultant BC was characterized for physical, chemical, and mineralogical properties specifically related to its potential use in remediation. The BC from all manures behaved similarly. Surface area, ash content, and pH of the BC increased as temperature increased, while yield decreased with increasing temperature. The BC was rich in mineral elements such as N, Ca, Mg, and P in addition to C, and concentrations of C and N decreased with increasing temperature as a result of combustion and volatilization; while P, Ca, and Mg increased as temperature increased. For example, C significantly decreased from 36.8% at 100 degrees C to 1.67% at 500 degrees C; whereas P increased from 0.91% to 2.66%. Water soluble P, Ca, and Mg increased when heated to 200 degrees C but decreased at higher temperatures likely due to increased crystallization of Ca-Mg-P, as supported by the formation of whitlockite (Ca,Mg)(3)(PO(4))(2) following 500 degrees C treatment. The presence of whitlockite was evidenced by X-ray diffraction analysis. Quartz and calcite were present in all BC produced. The BC showed appreciable capability of adsorption for Pb and atrazine from aqueous solution, with Pb and atrazine removal by as high as 100% and 77%, respectively. The results indicated that dairy manure can be converted into biochar as an effective adsorbent for application in environmental remediation.
将废物转化为生物炭（BC）被认为是废物处理和回收的几种选择之一。在这项研究中，我们通过在充足的空气条件下加热至低温（500°C）从奶制品废水中生产 BC。对所得 BC 的物理、化学和矿物学特性进行了表征，特别是与其在修复中的潜在用途有关的特性。所有肥料的 BC 行为相似。BC 的表面积、灰分含量和 pH 值随温度升高而增加，而产率随温度升高而降低。BC 富含除 C 以外的 N、Ca、Mg 和 P 等矿物质元素，随着燃烧和挥发，C 和 N 的浓度随温度升高而降低；而 P、Ca 和 Mg 的浓度随温度升高而增加。例如，C 从 100°C 时的 36.8%显著降低至 500°C 时的 1.67%；而 P 从 0.91%增加至 2.66%。当加热至 200°C 时，水溶性 P、Ca 和 Mg 增加，但在更高温度下减少，这可能是由于 Ca-Mg-P 的结晶增加所致，这得到了 500°C 处理后形成白榴石（Ca，Mg）（3）（PO4）2的支持。白榴石的存在通过 X 射线衍射分析得到证实。所有生产的 BC 中都存在石英和方解石。BC 对水溶液中的 Pb 和莠去津表现出相当高的吸附能力，Pb 和莠去津的去除率分别高达 100%和 77%。结果表明，奶制品废水可以转化为生物炭，作为应用于环境修复的有效吸附剂。
