Two sewage sludge ashes were used as substitutes for cement and their effect on the hygrothermal properties of mortar was examined. Different cement to ash ratios and two ash pre-treatment methods (water washing and grinding) were in focus. The impact of cement replacement by sewage sludge ashes on thermal conductivity, sorption isotherms, water vapour permeability and carbonation was described with standard cement-based mortar as the reference material. Measurement results showed that thermal conductivity decreased by 15% when 30% of the cement was replaced by sewage sludge ash. Water vapour permeability increased as the cement to ash ratio was reduced. Sorption was tested by two methods; although differences in the sorption isotherms of mortars were reported when a climatic chamber method was applied, no differences, or only minor differences, were observed with the desiccator method. Measurements revealed that cement-based mortar possessed a higher content of carbonate than cement-ash-based mortar, and it thus appears that the carbonation rate was higher when the cement content was high.

中文翻译：

---

水泥砂浆湿热性能的测定：焚烧污水污泥灰分部分替代水泥的效果

两种污水污泥灰被用作水泥的替代品，并研究了它们对砂浆湿热性能的影响。不同的水泥灰比和两种灰分预处理方法（水洗和粉磨）是重点。以标准水泥基砂浆为参考材料，描述了污水污泥灰分替代水泥对热导率、吸附等温线、水蒸气渗透率和碳化的影响。测量结果表明，当30%的水泥被污水污泥灰代替时，导热系数降低15%。随着水泥灰比的降低，水蒸气渗透率增加。通过两种方法测试吸附；虽然在应用气候室方法时报告了迫击炮的吸附等温线的差异，但没有差异或只有微小差异，用干燥器法观察。测量表明，水泥基砂浆比水泥灰基砂浆具有更高的碳酸盐含量，因此当水泥含量高时，碳化率似乎更高。