Department of Environmental Services, City and County of Honolulu, 91-174 Hanua St., Kapolei, HI 96707, USA.
Waste Manag. 2010 Mar;30(3):389-95. doi: 10.1016/j.wasman.2009.06.026. Epub 2009 Dec 1.
Non-hazardous industrial process wastes are receiving increased interest from landfill owners, especially with respect to bioreactor operation. These wastes could benefit bioreactors as they represent sources of liquid, nutrients, and/or substrate as well as revenue. However, landfill operators should exercise caution in accepting these wastes, as some could have detrimental effects on refuse decomposition. In this research, the use of laboratory-scale tests to evaluate the effect of one such waste on refuse decomposition is demonstrated. The waste evaluated, referred to as burnt sugar, is an acidic byproduct of corn-based polylactic acid production and represents a source of readily-biodegradable carbon. Lactic acid was the primary constituent of the BS at 0.73 g/g and the COD was measured at 1230 mg COD/g. Testing protocols were adapted to address the specific concerns surrounding the material. Abiotic dissolution tests conducted at mesophilic temperatures indicated that the majority of the waste dissolved into leachate recirculated over a layer of the waste within several days. Abiotic mixing tests suggested that the waste would acidify refuse to pH 6.41 at a loading of 21.9 g/dry kg refuse. However, in biologically active tests, the refuse was able to convert loadings as high as 196.7 g/dry kg refuse to methane. As the loadings increased toward and beyond this level, pronounced detrimental effects to the refuse ecosystem were observed, including a decrease in pH, accumulation of volatile fatty acids and COD, and lag in methane production. The results suggested that actively decomposing refuse has the potential to attenuate relatively high loading of a rapidly degradable but acidic substrate. Nonetheless, caution in the implementation of a field program to accept rapidly biodegradable acidic wastes is critical.
无害工业过程废物越来越受到垃圾填埋场所有者的关注，特别是在生物反应器操作方面。这些废物可以使生物反应器受益，因为它们是液体、营养物质和/或基质的来源，同时也是收入的来源。然而，垃圾填埋场运营商在接受这些废物时应谨慎，因为有些废物可能对垃圾分解产生不利影响。在这项研究中，展示了使用实验室规模的测试来评估一种这样的废物对垃圾分解的影响。评估的废物称为焦糖，是玉米基聚乳酸生产的酸性副产品，代表了易于生物降解的碳源。乳酸是 BS 的主要成分，含量为 0.73 g/g，COD 为 1230 mg COD/g。测试协议经过调整，以解决围绕该材料的具体问题。在中温下进行的非生物溶解测试表明，大部分废物在数天内溶解在回流水中循环的废物层中。非生物混合测试表明，废物将使垃圾酸化至 pH 6.41，负荷为 21.9 g/dry kg 垃圾。然而，在生物活性测试中，垃圾能够将高达 196.7 g/dry kg 垃圾的负荷转化为甲烷。随着负荷的增加，达到并超过这个水平，垃圾生态系统受到明显的不利影响，包括 pH 值下降、挥发性脂肪酸和 COD 的积累以及甲烷生成的滞后。结果表明，活跃分解的垃圾有潜力减轻相对较高的快速降解但酸性基质的负荷。尽管如此，在实施接受快速生物降解酸性废物的现场计划时谨慎行事至关重要。
