Study on oxygen-gas penetration mechanism and consumption reaction in sanitary landfills

得出了以下结论：1.卫生填埋场管网中空气流动的研究(1)当管网的每一端都向大气开放时，可以有相当数量的空气流入管道。(2)空气流动的驱动力是大气与填埋层之间的温差，以及填埋场表面风速势所产生的饱和压力。(3)因此，管道中的气体成分与大气几乎相同。(4)管道风量受管壁温度、填埋场表面风速、填埋层深度、管道堵塞等因素的影响。氧从管道渗入填埋层的研究(5)氧渗入填埋层的主要机理是氧浓度差的普通分子扩散。(6)氧渗透通量和深度受孔结构、氧耗反应速率、…等因素的影响。层中的更多和管道中的氧气浓度。(7)为了增加透氧量，需要一些设计或管理技术，如合理的管网设计，防止淤泥、粘土和淤泥等超细颗粒的填埋。在好氧垃圾或碎石层中好氧填埋层中可溶BOD去除能力的实验研究(8)中，利用好氧填埋层中的氧气浓度，可发生活性生物降解，耗氧速率等于TOC去除反应的速率，符合一元方程。(9)与有机碳相比，氨氮的氧化速率很低。实际底部渗滤液排放管道附近BOD去除潜力的估算(10)焚烧残渣、不可燃垃圾和混合垃圾填埋场渗滤液排放管道周围好氧带深度分别为0.5m、2.0m和0.2m。因此，经筛分的垃圾层对BOD的去除能力很低，而在不可燃垃圾和碎石层中的BOD去除能力很高，即可去除数千mg/L的BOD。(11)准好氧垃圾填埋场渗滤液BOD的稳定机理为好氧区圆形底渗滤液排放管中的生物降解。较少

The following conclusions were obtained.1. On air flow in a pipeline network in a sanitary landfill(1) A considerable amount of air can flow into the pipelines when every end of pipeline network is open to the atmosphere. (2) The driving forces of air flow are temperature difference between the atmosphere and landfill layer, and suctim pressure by a wind velocity potential on the surface of a landfill site. (3) Therefore, gas composition in pipelines is nearly the same as the atmosphere. (4) Air flow rate in pipelines is influenced by some factors, such as temperature of pipe wall, wind velocity on landfill surface, depth of landfill layer, and clogging in pipelines.2. On oxygen penetration through landfill layer from pipelines(5) Main mechanism of oxygen penetration through layer is ordinary molecular diffusion with oxygen concentration difference. (6) The flux and depth of oxygen penetration are influenced by some factors , such as pore structure, reaction rate of oxygen consumption … More in the layer and oxygen concentration in pipelines. (7) In order to increase amount of oxygen penetrating, some design or management technique are required, such as appropirate design of pipe line network, prevention of very fine particle such as silt, clay and sludge from landfilling.3. On experimental study about removal ability of soluble BOD in aerobic landfill layer(8) In aerobic refuse or crushed stone layer, active biodegradation occurs and the rate of oxygen consumption is equal to that of TOC removal reaction, which is described by the Monotype equation, using oxygen gas concentration in the layer. (9) Oxidation rate of ammonuium-nitrogen is very low, compared with one of organic carbon.4. On estimation of BOD removal potential in the neighborhood of actual bottom leachate discharge pipe(10) Depth of aerobic zone round leachate discharge pipe in incineration residue, incombustible refuse and mixed refuse landfills is 0.5, 2 and 0.2m respectively. Therefore BOD removal ability in sixed refuse layer is estimated to be very low, but ones in incombustible refuse and crushed stone layer are estimated to be high, that is, several thousands mg/L of BOD can be removed. (11) A stabilization mechanism of leachate BOD in semi-aerobic landfills is considered to be biodegradation in aerobic zone round bottom leachate discharge pipes. Less