Simultaneous solid and biocrude product transformations from the hydrothermal treatment of high pH-induced flocculated algae at varying Ca concentrations
Simultaneous solid and biocrude product transformations from the hydrothermal treatment of high pH-induced flocculated algae at varying Ca concentrations
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DOI：
10.1016/j.algal.2019.101501
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发表时间：
2019-06
期刊：
影响因子：
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通讯作者：
R. Hable;Sirwan Alimoradi;B. Sturm;S. Stagg-Williams
中科院分区：
文献类型：
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作者：
R. Hable;Sirwan Alimoradi;B. Sturm;S. Stagg-Williams
由于相当高的生长速率，藻类已成为生产生物燃料和可再生化学品的重要生物质原料，从而导致对培养和转化藻类生物质的成本竞争性手段的研究。废水流出物流为藻类生长提供必要的水和营养物输入，然而，所产生的藻类固体的低脂质、高灰分组成对于常规转化技术而言并不理想。水热液化（HTL）是一种利用亚临界水从废水培养的藻类固体中生产生物原油和高价值固体产品的整体藻类转化方法。本研究的目的是了解钙，废水培养的藻类固体的主要无机元素，如何影响最终HTL产品。在6个藻类生长池中改变钙浓度，并通过高pH诱导絮凝收获藻类。然后使用HTL在350 °C下处理藻类生物质1小时。碳酸钙是在藻类和HTL固体中观察到的主要晶体结构。一个HTL固体样品显示磷酸三钙的显著产生。较高的钙浓度导致HTL固体中磷的捕获接近100%。增加钙含量也对生物原油具有积极影响，包括H/C比、酰胺、烯烃和羧酸含量。这项研究的结果表明，从高pH值，絮凝收获收集的无机固体可能对生物原油具有非原位催化作用。
Because of the substantially high growth rate, algae have become a prominent biomass feedstock to produce biofuels and renewable chemicals leading to research on cost-competitive means to cultivate and convert algal biomass. Wastewater effluent streams provide the necessary water and nutrient inputs for algal growth, however, the low lipid, high ash composition of algal solids produced are not ideal for conventional conversion techniques. Hydrothermal liquefaction (HTL) is a holistic algal conversion method that utilizes subcritical water to produce biocrude and high-valued solid product from wastewater-cultivated algal solids. The objective of this study was to understand how calcium, the primary inorganic element of wastewater-cultivated algal solids, affects the final HTL products. The calcium concentration was varied in six algal growth tanks and the algae was harvestedviahigh pH induced-flocculation. The algal biomass was then processed using HTL at 350 °C for 1 h. Calcium carbonate was the primary crystalline structure observed in the algal and HTL solids. One HTL solid sample showed a significant production of tricalcium phosphate. The higher calcium concentrations resulted in near 100% capture of phosphorus in the HTL solids. Increasing the calcium content also had a positive impact on the biocrude including the H/C ratio, amide, alkene, and carboxylic acid content. The results of this study suggest that the inorganic solids collected from high pH, flocculated harvesting may have anin-situcatalytic impact on the biocrude.