Department of Environment and Planning / CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
Department of Materials and Ceramic Engineering / CICECO - Aveiro Institute of Materials, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
Bioresour Technol. 2020 Nov;316:123904. doi: 10.1016/j.biortech.2020.123904. Epub 2020 Jul 24.
Red mud-based inorganic polymer spheres were used as alternative pH regulators and process enhancers in sequencing batch anaerobic reactors treating cheese whey. This byproduct tends to quickly acidify under anaerobic conditions, and the common route to control pH and ensure suitable conditions for methane production involves the use of commercial alkaline raw materials. The spheres were synthesized using significant amounts of hazardous and toxic waste, red mud (50 wt% of solid components), whose recycling is challenging. The inorganic polymeric spheres, when compared to virgin alkaline raw materials, improved organic matter removal by 44%, prevented VFA accumulation (acidification degree less than 20%), maintained pH values in a range (6.5-7.2) to ensure maximum methanogenic activity by archaea microorganisms, and boosted the methane volume by ~90%. These promising results demonstrate the feasibility and performance advantages of using these innovative spheres instead of virgin raw materials, which is an important tool towards sustainable development.
以赤泥为基础的无机聚合物球被用作替代 pH 调节剂和序批式厌氧反应器处理奶酪乳清的工艺增强剂。这种副产物在厌氧条件下容易迅速酸化，而控制 pH 值并确保甲烷生产适宜条件的常见方法涉及使用商业碱性原料。这些球体是使用大量危险和有毒废物（赤泥（固体成分的 50wt%））合成的，而赤泥的回收具有挑战性。与原始碱性原料相比，无机聚合物球提高了 44%的有机物去除率，防止了 VFA 积累（酸化程度小于 20%），维持了 pH 值在一个范围内（6.5-7.2），以确保古细菌微生物的最大产甲烷活性，并将甲烷体积提高了约 90%。这些有希望的结果表明，使用这些创新的球体替代原始原料具有可行性和性能优势，这是可持续发展的重要工具。
