污泥防辐射功能集料的制备及性能

基于重金属元素对高能射线具有优良屏蔽性能的特点,以含10％(质量分数,下同)钡元素的某化工厂污泥为原材料,辅以高岭土、分析纯化学物质为校正材料,通过对生料的配合比优化设计,在一定的煅烧制度下制备出了重金属离子溶出率小、射线屏蔽性能较好的功能集料.试验结果表明:该集料的表观密度达2.95×103 kg/m3,吸水率达1.57％,抗压强度达82 MPa,Ba离子浸出率低至1 mg/L,线性衰减系数达0.243 9 cm-1,可作为集料替代天然重晶石集料制备防辐射混凝土.

Preparation and Properties of Radiation Shielding Functional Aggregate Based on Sludge

Considering that heavy metal elements possess the characteristic of high energy radiation shielding, chemical sludge containing 10%(by mass) barium was used as raw material. Meanwhile, kaolin and analytically pure chemicals were supplemented as correction materials. Through optimization design of the mix proportion of raw material, the functional aggregate with low heavy metal release rate and excellent performance of radiation shielding was prepared in proper calcination system. The results show that, the functional aggregate bulk density reaches 2.95×103kg/m3, water absorption is as low as 1.57%, compressive strength is as high as 82MPa, barium ion leaching rate is 1mg/L, and the linear attenuation coefficient is as low as 0.2439cm-1. Therefore, the functional aggregate is expected to be able to replace barite ore in the radiation shielding concrete.