管学茂, 王雪晴, 郅真真.聚羧酸减水剂对脱硫石膏水化硬化性能的影响与作用机理[J].河南理工大学学报（自然科学版）,2025,44(5):187-192.

GUAN X M, WANG X Q, ZHI Z Z.column:Effects and mechanisms of polycarboxylate superplasticizer on the hydration and hardening behavior of construction-grade desulfurized  gypsum[J].Journal of Henan Polytechnic University(Natural Science) ,2025,44(5):187-192.

聚羧酸减水剂对脱硫石膏水化硬化性能的影响与作用机理

管学茂1, 王雪晴1, 郅真真2

1.河南理工大学 材料科学与工程学院，河南 焦作  454000；2.洛阳理工学院 材料科学与工程学院，河南 洛阳  471023

摘要: 目的 为改善脱硫石膏硬化体性能，资源化利用燃煤电厂烟气脱硫等途径产生的大量脱硫石膏，减少工业副产石膏堆存，本文合成一种聚羧酸高效减水剂（polycarboxylate superplasticizer， PCE），并研究其对β-半水脱硫石膏（β-hemihydrate desulfurization gypsum， β-HDG）的影响。 方法 研究不同掺量PCE对β-HDG水化过程中的流动性、吸附行为、浆体Zeta电位和石膏硬化体抗压抗折强度的影响。通过X射线衍射（XRD）、扫描电子显微镜（SEM）分析PCE作用下石膏硬化体的晶体组成和微观形貌。  结果 随PCE掺量的增加，石膏浆体流动度和减水率均先增加后稳定，当PCE掺量为0.4%时，石膏浆体流动度达到248 mm，减水率为26%，石膏浆体标稠需水量降低至37%。随着PCE掺量的增加和吸附时间的延长，PCE在石膏表面的吸附量变化先增加后稳定，PCE掺量为0.4%时达到饱和，此时吸附量为3.6mg/g。石膏浆体的Zeta电位随着PCE掺量增加而不断降低。石膏硬化体的力学强度随着PCE掺量的增加而提高，当PCE掺量为0.4%时，石膏硬化体抗压强度、抗折强度分别达到24.7MPa和5.81MPa，比空白样分别提高32.6%和21.5%。 结论 PCE的加入能够改善石膏浆体的流动度，降低石膏浆体的标准稠度需水量，并提高脱硫石膏硬化体强度。PCE的加入并没有改变石膏硬化体的晶体相组成，但使晶体之间网状搭接更紧密，需水量降低和内部孔隙降低是石膏硬化体宏观强度增加的关键因素。

关键词:β-半水脱硫石膏;聚羧酸高效减水剂;硬化;抗折强度;抗压强度

DOI:10.16186/j.cnki.1673-9787.2023120038

基金项目:国家自然科学基金资助项目（U1905216）

收稿日期:2023/12/13

修回日期:2024/02/22

出版日期:2025/07/23

Effects and mechanisms of polycarboxylate superplasticizer on the hydration and hardening behavior of construction-grade desulfurized  gypsum

Guan Xuemao1, Wang Xueqing1, Zhi Zhenzhen2

1.School of Materials Science and Technology， Henan Polytechnic University， Jiaozuo  454000， Henan， China；2.School of Materials Science and Technology ， Luoyang Institute of Science and Technology， Luoyang  471023， Henan， China

Abstract: Objectives To improve the performance of hardened desulfurized gypsum and promote the resource utilization of by-product gypsum from flue gas desulfurization in coal-fired power plants， a polycarboxylate superplasticizer （PCE） was synthesized， and its effects on the hydration and hardening behavior of β-hemihydrate desulfurized gypsum （β-HDG） were investigated. Methods The influence of varying PCE dosages on the fluidity， adsorption behavior， and zeta potential of β-HDG slurry， as well as the compressive and flexural strengths of hardened specimens， was studied. X-ray diffraction （XRD） and scanning electron microscopy （SEM） were employed to analyze the crystal phase composition and microstructure of the hardened gypsum. Results As the PCE dosage increased， both slurry fluidity and water-reducing efficiency first increased and then stabilized. At a dosage of 0.4%， the slurry exhibited a maximum fluidity of 248 mm and a 26% water-reduction rate， with standard consistency water demand reduced to 37%. The adsorption capacity of PCE on gypsum surfaces also increased and then stabilized with prolonged adsorption time， reaching a saturation value of 3.6 mg/g at 0.4% dosage. The zeta potential of the slurry decreased with increasing PCE content. The compressive and flexural strengths of the hardened gypsum peaked at 24.7 MPa and 5.81 MPa， respectively， representing increases of 32.6% and 21.5% over the blank sample. Conclusions The addition of PCE improves slurry workability and reduces water demand for standard consistency， thereby enhancing the mechanical strength of hardened desulfurized gypsum. While the crystal phase composition remains unchanged， the denser networked crystal structure and lower porosity contribute significantly to the improved macro-strength of the hardened product.

Key words:-Hemihydrate desulfurized gypsum;polycarboxylate superplasticizer;hardening;flexural strength;compressive strength