煅烧白云石催化热解剩余污泥特性研究

Study on the characteristics of residual sludge from catalytic pyrolysis with calcined dolomite

白云石含有丰富的碱土金属元素,分布广泛,价格低廉,煅烧后的白云石(DE)可作为剩余污泥热解催化剂。采用热重分析、气相色谱以及气相色谱/质谱联用等技术,分析了剩余污泥热解行为和热解产物特性,阐明了DE在不同热解条件下对剩余污泥催化热解过程及热解产物的影响。结果表明:≥700℃条件下DE的投加强化了剩余污泥挥发分的析出,促进了剩余污泥的裂解。与剩余污泥单独热解相比,DE导致污泥热解前期固体产率增高,在热解后期,尤其在700℃之后,催化热解产气优势显著,不仅提升了可燃性气体含量,同时改善了液体产物品质。DE的投加对剩余污泥催化热解具有提升热解产物性能和资源再利用的优势,对实现剩余污泥的高效资源化利用具有重要意义。

Dolomite is rich in alkaline earth metal elements,widely distributed,low price,calcined dolomite(DE)can be used as a residual sludge pyrolysis catalyst.Thermogravimetric analysis,gas chromatography and gas chromatography/mass spectrometry were used to analyze the pyrolysis behavior and pyrolysis product characteristics of residual sludge,and the effects of DE on the catalytic pyrolysis process and pyrolysis products of residual sludge under different pyrolysis conditions were clarified.The results showed that the addition of DE at≥700℃enhanced the volatilization of residual sludge and promoted the decomposition of residual sludge.Compared with the pyrolysis of residual sludge alone,DE led to a higher solid yield in the early stage of residual sludge pyrolysis,and in the later stage of pyrolysis,especially after 700℃,the catalytic pyrolysis gas production had a significant advantage,which not only increased the content of flammable gas,but also improved the quality of liquid products.In conclusion,the addition of DE to the catalytic pyrolysis process enhanced the quality of the pyrolysis products and facilitated the resource reuse of residual sludge,holding great significance for the efficient utilization of residual sludge.