造纸黑液磺化工艺及用作混凝土减水剂的研究

Study on sulfonated process of pulp black liquor and the application as concrete water reducer

采用先活化磺化再缩聚的工艺,以造纸黑液为主要原料,改性制备混凝土减水剂。改性黑液产品GSBL在掺量0.5%、水灰比0.38的条件下,水泥净浆流动度可达224 mm。当GSBL掺量为0.5%时,砂浆减水率达到11.8%,28 d抗压和抗折强度较空白砂浆分别提高22%和26%,性能优于木质素磺酸钙。将GSBL与FDN按质量比1∶4进行复配,掺加复配产品的混凝土与相同条件下掺FDN减水剂的混凝土具有相同的初始坍落度,而28 d抗压强度也相近,GSBL与FDN复配对提高FDN产品的性价比有明显效果。

The concrete water reducer was prepared from pulp black liquor by sulfonation and then condensation reaction. When the content of modified black liquor GSBL is 0.5% and water to cement ratio of 0.38,the fluidity of cement paste was up to 224mm. The water reducing ratio of mortar with 0.5% GSBL was 11.8%,and the compression strength and flexure strength of mortar at 28 d were up to 22% and 26% respectively compared with blank mortar and its performance is superior to that of calcium lignosulfonate. When GSBL mixed with FDN at the mass ratio of 1：4,the initial slump constant of the concrete with mixture plasticizer is equal to that of concrete mixed with FDN water reducer under the same conditions,and their 28d compressive strength is near. Adding GSBL into FDN has obvious effect to increase performance/price ratio of the FDN product.