工程泥浆脱水泥饼制备烧结陶粒及其性能研究

Preparation and Properties of Sintered Ceramsite Prepared by Engineering Slurry Dehydrated Slurry Cake

为了寻求工程泥浆的高值资源化利用有效途径,以经机械脱水泥饼为主要原料,掺加不同比例的粉煤灰和钢渣制备陶粒,设计了高含水率泥饼制备陶粒的成型设备和工艺流程,探究了化学组成对陶粒性能的影响,测试了陶粒混凝土和易性及强度性能,并与普通混凝土进行了对比。研究表明:掺入适量钢渣能有效提升陶粒的强度,降低吸水率;而粉煤灰则反之,主要原因是钢渣的掺入优化了黏土的SA/R(难熔成分与助熔成分质量比),而粉煤灰的掺入则劣化了该比值。当钢渣掺入量为10%(质量分数)时,烧结陶粒的筒压强度为5.8 MPa,吸水率为10.4%,堆积密度为1 076 kg·m^(-3),表观密度为2 010 kg·m^(-3),满足《陶粒混凝土技术规程》(DBJ/T 15-62—2021)中关于高强陶粒的使用要求,可以应用于陶粒混凝土。按C45设计的陶粒混凝土抗压强度为23.49 MPa,流动性较好,表观密度较低,能降低其12.4%的自重,适用于非承重结构。

In order to seek an effective way for the high-value resource utilization of engineering slurry,ceramsite was prepared by adding different proportions of fly ash and steel slag with mechanically dehydrated slurry cake as the main raw material,and the molding equipment and process flow for preparing ceramsite with high water content slurry cake were designed.The influence of chemical composition on the properties of ceramsite was investigated.The workability and strength properties of ceramsite concrete were tested and compared with ordinary concrete.The results show that adding the appropriate amount of steel slag can effectively improve the strength of ceramsite and reduce the water absorption,however fly ash is opposite.The main reason is that the adding of steel slag optimizes the SA/R(mass ratio of refractory component to fluxing component) of clay,while the adding of fly ash deteriorates SA/R.When the content of steel slag is 10%(mass fraction),the compressive strength of the sintered ceramsites is 5.8 MPa,the water absorption rate is 10.4%,the bulk density is 1 076 kg·m^(-3),and the apparent density is 2 010 kg·m^(-3),which meets the requirements of the Technical specification for ceramsite concrete(DBJ/T 15-62—2021) for the use of high-strength ceramsite and can be applied to ceramsite concrete.The compressive strength of ceramsite concrete designed according to C45 is 23.49 MPa.The fluidity of ceramsite concrete is good,the apparent density is low,and the self-weight can be reduced by 12.4%,which is suitable for non-load-bearing structures.