通过生物固体鼓干燥机与再生热氧化剂控制排放的PFAS的命运
John J Ross1, Alex Seidel1, Embrey Bronstad1
1Brown and Caldwell, Walnut Creek, California, USA.
概括
热干燥器显著减少生物固体中的和多基物质 (PFAS),大多数PFAS存在于干燥的固体中,而不是废水中. 再生热氧化剂有效地破坏PFAS,但需要对转化产品进行进一步的研究.
科学领域:
- 环境工程 环境工程
- 化学工程是化学工程的重要组成部分.
- 环境化学环境化学
背景情况:
- 热干燥器被广泛用于生物固体处理,但它们对和多醇基物质 (PFAS) 的影响尚不清楚.
- 了解热干燥过程中的PFAS命运对于管理废水处理过程中环境污染至关重要.
研究的目的:
- 研究生物固体在全面热干燥过程中PFAS的去除和转化.
- 评估再生热氧化剂 (RTO) 在干燥机排放中破坏PFAS的效率.
- 量化PFAS在干燥固体,废水和气体排放中的分布.
主要方法:
- 来自全尺寸旋转鼓式干燥机的三重样本的分析,包括料,干燥固体,洗水和气相排放.
- 使用已确定的分析技术,在不同阶段量化目标PFAS.
- 评估整个干燥机的PFAS清除和整个RTO的破坏效率.
主要成果:
- 在生物固体料和干燥固体之间观察到大量的目标PFAS (60.0%在总摩尔基础上) 的去除.
- 在湿洗机排水中没有积累PFAS,并且擦洗的废气显示PFAS度明显较低.
- 该RTO实现了高的PFAS破坏效率 (93.5%99.3%),尽管由于HFPO-DA的存在而复杂化.
结论:
- 热干燥过程导致生物固体中的PFAS显著减少,主要是分离到干燥的固体.
- 湿洗机有效地从干燥机排气中去除PFAS,而RTO显示出高的破坏效率.
- 需要对热干燥系统中的PFAS转化途径和产品进行进一步的研究,以充分考虑PFAS余额.
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