Liu Rui, Coffman Reid
College of Architecture and Environmental Design, Kent State University, Kent, OH 44242, USA.
Materials (Basel). 2016 Jul 23;9(8):611. doi: 10.3390/ma9080611.
More than 1.15 million cubic meters (1.5 million cubic yards) of sediment require annual removal from harbors and ports along Ohio's Lake Erie coast. Disposing of these materials into landfills depletes land resources, while open water placement of these materials deteriorates water quality. There are more than 14,000 acres of revitalizing brownfields in Cleveland, U.S., many containing up to 90% impervious surface, which does not allow "infiltration" based stormwater practices required by contemporary site-based stormwater regulation. This study investigates the potential of sintering the dredged material from the Harbor of Cleveland in Lake Erie to produce lightweight aggregate (LWA), and apply the LWA to green roof construction. Chemical and thermal analyses revealed the sintered material can serve for LWA production when preheated at 550 °C and sintered at a higher temperature. Through dewatering, drying, sieving, pellet making, preheating, and sintering with varying temperatures (900-1100 °C), LWAs with porous microstructures are produced with specific gravities ranging from 1.46 to 1.74, and water absorption capacities ranging from 11% to 23%. The water absorption capacity of the aggregate decreases as sintering temperature increases. The LWA was incorporated into the growing media of a green roof plot, which has higher water retention capacity than the conventional green roof system.
每年需要从俄亥俄州伊利湖沿岸的港口清除超过115万立方米（150万立方码）的沉积物。将这些材料处置到垃圾填埋场会耗尽土地资源，而将这些材料排放到开阔水域会恶化水质。美国克利夫兰有超过14000英亩正在复兴的棕地，其中许多含有高达90%的不透水表面，这不符合当代基于场地的雨水法规所要求的基于“渗透”的雨水处理措施。本研究调查了将伊利湖克利夫兰港疏浚物烧结以生产轻集料（LWA）并将其应用于绿色屋顶建设的潜力。化学和热分析表明，当在550℃预热并在更高温度下烧结时，烧结材料可用于生产轻集料。通过脱水、干燥、筛分、制粒、预热以及在不同温度（900-1100℃）下烧结，制备出了具有多孔微观结构的轻集料，其比重范围为1.46至1.74，吸水能力范围为11%至23%。集料的吸水能力随着烧结温度的升高而降低。这种轻集料被掺入绿色屋顶地块的种植介质中，该种植介质比传统绿色屋顶系统具有更高的保水能力。
