Abstract:

Under the background of global warming and China’s "double carbon" goal, the concept of "chemical wastewater treatment and CO₂co-utilization" is proposed in this paper, and purified terephthalic acid (PTA) production wastewater treatment and CO₂co-utilization are selected to produce microalgal biomass. Laboratory study and pilot test lasted for 124 days are carried out. The experimental results show that the COD removal rate is more than 92%, the CO₂ (10%volume fraction) capture rate is more than 93%, and the CO₂ capture intensity was 9—11kg/t wastewater. The residual biomass is treated by pyrolysis, and the pyrolysis rate of biomass is >95%. A closed-loop carbon conversion and utilization system is applied to treat and utilize carbon in wastewater, gases and solids. The conversion from "useless carbon" to "usable carbon" is realized, which provided a new way for the goal of carbon neutralization in chemical enterprises.

Key words: carbon neutralization, purified terephthalic acid (PTA), wastewater treatment, CO₂co-utilization

摘要：

在全球变暖的严峻形势和我国“双碳”目标的大背景下，本文提出了“化工废水处理与CO₂协同利用”概念，选择精对苯二甲酸（PTA）生产废水处理与CO₂协同利用生产微藻生物质，开展了实验室研究和为期124天的中试试验。实验结果表明，实现了PTA生产废水COD去除率达到92%以上，对CO₂（体积分数10%）捕集率达到93%以上，CO₂捕集强度为9~11kg/t废水。产生的剩余生物质通过热裂解处理，生物质热裂解率>95%。通过闭环的碳转化，利用体系处理，利用废水、气体和固体中的碳，实现了从“无用碳”到“可用碳”的转化，为化工企业的碳中和目标提供了新的思路。

关键词: 碳中和, 精对苯二甲酸, 废水处理, CO₂协同利用, 微藻生产