Valorization of hydrothermal liquefaction aqueous stream towards commercial viability of municipal sludge to biocrude oil conversion

水热液化水流的价值对城市污泥转化为生物原油的商业可行性

• 批准号: RGPIN-2022-03692
• 负责人: Eskicioglu, Cigdem
• 金额: $ 3.79万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=761755
• 关键词: Valorization; hydrothermal; liquefaction; aqueous; stream

My overarching research program focuses on the development of advanced wastewater and sludge treatment technologies, and is motivated by many of the challenges my industrial collaborators/partners currently face. In particular, municipal wastewater treatment plants are increasingly stretched by ever growing volumes of hazardous materials in wastewater that become part of `municipal sludge.' This sludge is costly to process in order to effectively neutralize the pathogens, heavy metals, and a wide range of trace contaminants of emerging concern (TCECs) that it contains. My recent research has investigated several promising approaches to process this waste product, including thermochemical sludge conversion through hydrothermal liquefaction (HTL). HTL is a game-changing advancement, since it can convert sludge into biocrude that can be used as a fuel replacement. To date we have found that dewatered municipal sludge can be efficiently converted to biocrude oil and hydrochar at temperature and pressure of 350 C and 220 bar, respectively. Furthermore, at these elevated temperatures and pressures, many classes of TCECs (pharmaceuticals, hormones, antimicrobials) in municipal sludge are destroyed. Since this promising technology has the potential to sterilize the hazardous materials in municipal wastewater sludge by generating fuel that can be used in transportation, it has the double advantage of reducing costs associated with many other wastewater treatment solutions, and provides environmental benefits on several fronts. However, HTL creates a by-product, HTL aqueous, that without additional treatment, jeopardizes the future scale-up prospects of this technology at wastewater treatment plants. The pollutant levels in HTL aqueous significantly exceed discharge regulations to the environment and the risks of returning it to headworks is unknown. The HTL aqueous is also an untapped nutrient/bioenergy resource that holds revenue-generating potential for treatment plants due to its high concentration of organic acids. However, there are also many classes of organics, including furans, ketones, phenols, and N-heterocyclic compounds, reported to be inhibitory to key microbial cultures in biological treatment processes, in particular anaerobic digesters with bioenergy recovery potential. Therefore, bioenergy potential of HTL aqueous is unknown. To address these gaps, over the next 5 years, 3 graduate and 2 undergraduate students, mentored by an analytical chemist, will develop and evaluate the performance of various detoxification methods for HTL aqueous derived from municipal sludge to valorize high concentrations of organic acids to generate biogas in advanced anaerobic digesters. These objectives will bring us one step closer to incorporating HTL sludge conversion processes to wastewater treatment plants seamlessly. Through ongoing partnerships with municipalities throughout British Columbia, outcomes of this research are poised to have immediate impact.

我的总体研究计划侧重于先进废水和污泥处理技术的开发，并受到我的工业合作者/合作伙伴目前面临的许多挑战的推动。特别是，由于废水中有害物质的数量不断增加，这些物质成为“城市污泥”的一部分，城市废水处理厂的负荷日益增加。为了有效中和其中含有的病原体、重金属和各种新出现的痕量污染物 (TCEC)，这种污泥的处理成本很高。我最近的研究调查了几种有前途的处理这种废物的方法，包括通过水热液化（HTL）进行热化学污泥转化。 HTL 是一项改变游戏规则的进步，因为它可以将污泥转化为可用作燃料替代品的生物原油。迄今为止，我们发现脱水后的城市污泥可以分别在 350°C 和 220bar 的温度和压力下有效转化为生物原油和水力炭。此外，在高温和高压下，城市污泥中的多种 TCEC（药物、激素、抗菌剂）都会被破坏。由于这项有前途的技术有潜力通过产生可用于运输的燃料来消毒城市废水污泥中的有害物质，因此它具有降低与许多其他废水处理解决方案相关的成本的双重优势，并在多个方面提供环境效益。然而，HTL 会产生一种副产品 HTL 水溶液，如果不进行额外处理，就会危及该技术在废水处理厂未来规模化的前景。 HTL 水溶液中的污染物水平显着超出环境排放规定，并且将其返回渠首工程的风险尚不清楚。 HTL 水溶液也是一种未开发的营养/生物能源资源，由于其高浓度的有机酸，具有为处理厂创收的潜力。然而，据报道，还有许多类别的有机物，包括呋喃、酮、酚和 N-杂环化合物，对生物处理过程中的关键微生物培养物具有抑制作用，特别是具有生物能源回收潜力的厌氧消化池。因此，HTL 水溶液的生物能源潜力尚不清楚。为了弥补这些差距，在接下来的 5 年里，3 名研究生和 2 名本科生将在分析化学家的指导下，开发和评估来自城市污泥的 HTL 水的各种解毒方法的性能，以评估高浓度的有机酸，以产生先进厌氧消化池中的沼气。这些目标将使我们距离将 HTL 污泥转化工艺无缝融入废水处理厂又近了一步。通过与不列颠哥伦比亚省各地市政府的持续合作，这项研究的成果有望产生立竿见影的影响。