The Influence of Different Kinds of Retarders on the Coagulation Time and Hardening Properties of Hemihydrate Phosphogypsum
WANG Jiahao1, SHEN Yu2, LIU Juanhong1,3,4, LUO Kun1
1 School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing 100083,China 2 The Third Engineering Co., Ltd., CCCC Second Highway Engineering Co., Ltd., Xi'an 710016, China 3 Beijing Key Laboratory of Urban Underground Space Engineering, University of Science and Technology Beijing, Beijing 100083, China 4 Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 100083,China
Abstract: In order to solve the problem of too fast setting time of hemihydrate phosphogypsum, five typical retarders-citric acid, tartaric acid, bone glue, sodium gluconate and sodium tripolyphosphate were selected to explore the effects of different amount of retarder on the water consumption of standard consistency, setting time, compressive strength and hydration heat release of hemihydrate phosphogypsum paste. The results showed that the five retarders can prolong the initial setting time and final setting time of hemihydrate phosphogypsum and reduce the water consumption of standard consistency of hemihydrate phosphogypsum. In the case of 0.1% low content, tartaric acid and sodium gluconate have the best retarding effect, and the initial setting time and final setting time are more than 6 times that of the blank sample without retarder, and the strength loss rate is less than 20% to 30% in 3 d and 7 d. Among them, sodium gluconate can reduce the peak heat release rate 22.1%, and the occurrence time of the peak rate is more than doubled. Considering comprehensively, tartaric acid and sodium gluconate can prolong the setting time of hemihydrate phosphogypsum, reduce the hydration heat release rate, and the strength loss rate of hardened body is lower.
王嘉昊, 沈玉, 刘娟红, 罗昆. 不同种类缓凝剂对半水磷石膏凝结时间和硬化性能的影响[J]. 材料导报, 2022, 36(Z1): 21120173-5.
WANG Jiahao, SHEN Yu, LIU Juanhong, LUO Kun. The Influence of Different Kinds of Retarders on the Coagulation Time and Hardening Properties of Hemihydrate Phosphogypsum. Materials Reports, 2022, 36(Z1): 21120173-5.