油泥燃烧特性的试验

Study on the combustion characteristics of oil sludge

本文利用热重红外联用配合同步差热分析实验台和小型鼓泡流化床实验台共同研究了油泥的燃烧特性.由热重红外联用和同步差热分析研究发现,油泥的着火温度较低,燃尽较容易,油泥在热解过程中,轻质烃的析出开始于425 K,重质有机成分在600—800 K析出显著,油泥燃烧过程中主要放热阶段位于550 K以上发生的重质有机成分的分解和燃烧.鼓泡流化床燃烧实验结果发现,典型的油泥鼓泡流化床燃烧分为3个阶段:挥发分剧烈燃烧,挥发分弱燃烧和固定碳燃烧.通过热平衡计算得出鼓泡流化床油泥燃烧稀相区和密相区的燃烧比,结果表明稀相区的油泥燃烧比高达80.5%,稀相区是主要的燃烧放热区域,该区域发生的反应是重质有机成分的分解和燃烧.因此,在实际流化床锅炉中,对气相燃烧组织和炉内热量分布需要做特殊考虑.

A considerable quantity of harmful oil sludge is produced by the petroleum industry during crude oil exploitation, transportation,and refining process. Combustion is considered to be an efficient treatment of oil sludge. This study investigated the combustion characteristics of oil sludge through thermogravimetric （TG） analysis combined with fourier-transformed infrared spectroscopy （FTIR） and synchronization differential thermal analytical （SDTA） analysis and combustion in bubbling fluidized bed （BFB）. Firstly,the results of the TG-FTIR and SDTA analysis show that the oil sludge had low ignition temperature and was easily burnt out. The volatilization of low mass hydrocarbons started at 425 K and the release of heavy organic matters was significant in the range 600—800 K. The decomposition and combustion of heavy organic matters taking place at the temperatures above 550 K was the key process during which the largest amount of heat was released during oil sludge combustion. The results from BFB test indicate that the typical process of oil sludge combustion in BFB contained three stages： violent combustion of volatiles in dilute region,weak combustion of volatiles and combustion of fixed carbon in dense region. The combustion ratio of oil sludge in the dilute region was calculated as 80.5%,which indicated that the region characterized by the richest amount of heat was the dilute one. The decomposition and combustion of heavy organic matters took place in the dilute region. Thus the combustion organization of gas phase in the dilute region and heat distribution in furnace should be specially considered in actual fluidized bed boiler.