Abstract:

Sintered products were prepared using coal gasification slag as the main raw material.Based on the comprehensive differential thermal analysis of dry mixture and the firing shrinkage pre-tests of green bodies as well as experience,the experiment was conducted according to orthogonal table L₉(3 ³),selecting the heating rate,the firing temperature,and the holding time as factors,2,3,and 4 ℃·min ^-1,1 100,1 150,and 1 200 ℃ as well as 2,4,and 6 h as the corresponding levels,while the bulk density,the water absorption,the compressive strength and the thermal conductivity as evaluation indexes.The results show that:(1)the order of the influence degree of the firing system factors on the compressive strength,the bulk density and the water absorption of the sintered products is the firing temperature>the holding time>the heating rate,and that for the thermal conductivity is the firing temperature>the heating rate>the holding time;(2)generally,the optimal firing system is the heating rate of 2 ℃·min ^-1,the firing temperature of 1 200 ℃,and the holding time of 6 h,and the prepared sample has the bulk density of 1.84 g·cm ^-3,the compressive strength of 112 MPa,the water absorption of 1.44%,and the thermal conductivity of 1.239 W·m ^-1·K ^-1.

Key words: coal gasification slag, sintered products, orthogonal table, firing system

摘要：

以煤气化渣为主要原料制备烧结制品,通过干混料的综合差热分析和样坯的烧成收缩预试验,再根据以往经验,选取升温速率(A)、烧成温度(B)和保温时间(C)三个因素,并分别选取2、3、4 ℃·min ^-1,1 100、1 150 和1 200 ℃,2、4、6 h为因素水平,选取烧结制品的体积密度、吸水率、耐压强度和热导率为评价指标,按正交表L₉(3 ³)安排试验。结果表明:1)烧成制度各因素对烧结制品的耐压强度、体积密度和吸水率影响程度的大小顺序均为烧成温度>保温时间>升温速率,对热导率影响程度的大小顺序为烧成温度>升温速率>保温时间。2)经综合平衡考虑,最优试验方案为:升温速率2 ℃·min ^-1,烧成温度1 200 ℃,保温时间6 h。所得试样的体积密度为1.84 g·cm ^-3,耐压强度为112 MPa,吸水率为1.44%, 热导率为1.239 W·m ^-1·K ^-1。

关键词: 煤气化渣, 烧结制品, 正交表, 烧成制度