污泥焚烧炉渣/硝酸钾复合相变储热材料制备及性能OA北大核心CSTPCD

Improperly treated municipal sludge can lead to significant ecological damage,making it essential to find effective mitigation strategies.Incineration offers a viable solution to reduce this harm,but the resulting residue may still contain heavy metals that are difficult to stabilize.To effectively address this issue and develop low-cost and environmentally friendly composite phase change thermal storage materials,a novel approach proposes using municipal sludge incineration residue as the skeleton material and potassium nitrate as the phase change thermal storage material.Five different mass ratios of sludge incineration residue to potassium nitrate were prepared using cold-pressing and sintering methods.The materials were evaluated based on their macroscopic and microscopic appearances,compressive strength,thermal stability,chemical compatibility,heat transfer,and thermal storage properties.Economic feasibility and CO2 emissions were also analyzed.The results show that within the temperature range of 100-380℃,the optimal mass ratio of sludge incineration residue to potassium nitrate is 5∶5(sample SC3).This composition achieves a heat storage density of 322.45 J/g,latent heat of 41.75 J/g,and maximum thermal conductivity of 1.04 W/(m∙K).The compressive strength reaches 153.78 MPa,indicating that the materials exhibit good chemical compatibility and are evenly distributed in sample SC3.Additionally,sample SC3 shows good high-temperature thermal stability,maintaining performance after 1000 heating/cooling cycles.The thermal storage cost is calculated at 63.06 CNY/MJ,and the total CO2 emissions are 1083.53 kg/t,which are lower than those associated with traditional skeleton material-based composite phase change thermal storage materials.This suggests that the approach offers both environmental benefits and practical feasibility.