Innovative use of compost as biocover for landfill

与垃圾填埋相关的主要环境挑战之一是垃圾填埋气体(LFGs)的产生--主要是甲烷(CH4)和二氧化碳(CO2)。在垃圾填埋场覆盖系统中，通过一种被称为“甲烷氧化菌”的细菌亚群，微生物介导的甲烷氧化已被广泛接受为一种对抗垃圾填埋场甲烷排放的方法。甲烷氧化菌将甲烷作为其唯一的碳和能源来源进行代谢，并自然地存在于有足够浓度的甲烷和二氧化碳维持其生存的环境中，例如垃圾填埋场覆盖土壤的上层。最近，研究集中在通过选择适当的覆盖材料和改良剂(如堆肥)来增加垃圾填埋场CH4的氧化程度的方法，这些材料和改良剂可以为甲烷氧化菌的生长创造有利条件。这种利用垃圾填埋场甲烷氧化过程的覆盖系统被称为“基于生物的”或“工程的”覆盖系统，具有进一步减少甲烷排放的潜力。拟议研究的总体目标是评估堆场和树叶垃圾堆肥和生物固体堆肥的混合物在温尼伯封闭垃圾填埋场现场规模应用中作为生物覆盖物氧化甲烷的效果。将评估降水、环境温度和大气压力等气候因素对系统整体性能的影响，以确定生物垃圾填埋场覆盖的概念是否能成功应用于寒冷气候。拟议的研究将提供科学证据，使KGS集团相信在像马尼托巴省那样恶劣和多变的气候下应用垃圾填埋场生物覆盖。生物覆盖可能是在产量较低或较老的垃圾填埋场收集甲烷的最有效和最经济的解决方案，因为在加拿大和气候寒冷的地区安装全面的气体收集系统在经济上是不可行的。此外，这项研究将找到一个可持续的解决方案，重新利用堆场，并将废物和生物固体作为垃圾生物覆盖物，这不仅将使温尼伯市受益，也将使加拿大其他市政当局受益。

One of the major environmental challenges associated with landfills is the generation of landfill gases (LFGs) - primarily methane (CH4) and carbon dioxide (CO2). Microbially -mediated methane oxidation in landfill cover systems via a subset of bacteria known as "methanotrophs" has been widely accepted as a method to counter landfill methane emissions. Methanotrophs metabolize methane as their only source of carbon and energy and are naturally found in environments where there are sufficient concentrations of CH4 and CO2 to sustain their survival, such as the upper layers of a landfill cover soil. More recently, research has focused on methods to increase landfill CH4 oxidation by selecting suitable cover materials and amendments, such as composts, that induce favourable conditions for the growth of methanotrophs. Such cover systems that exploit the landfill methane oxidation process have been termed "bio-based" or "engineered" cover systems and have the potential to further reduce CH4 emissions. The overall objective of the proposed research is to assess the efficacy of a mixture of yard and leaf waste compost and biosolids compost as biocover in oxidizing methane within a field-scale application on a closed landfill in Winnipeg. The effect of climatic factors such as precipitation, ambient temperature, and atmospheric pressure on the overall performance of the system will be evaluated in order to determine if the concept of a biological landfill cover can successfully be applied to cold climates.The proposed research will provide scientific proof that allows KGS Group to be confident of the application of the landfill biocover within a climate that is as harsh and varied as Manitoba's. The biocover can be the most effective and economical solution for capturing the methane at lower-producing or older landfills where it is not economically feasible to install a full-expanse gas collection system in Canada as well as areas with a cold climate. In addition, this research will find a sustainable solution to reuse of yard and leave waste and biosolids as landfill biocover which will not only benefit the City of Winnipeg, but other municipalities across Canada.