Journal of Biotechnology ( IF 4.1 ) Pub Date : 2020-08-04 , DOI: 10.1016/j.jbiotec.2020.07.022 Francesco Valentino 1 , Laura Lorini 1 , Marco Gottardo 2 , Paolo Pavan 2 , Mauro Majone 1
The utilisation of urban organic waste as feedstock for polyhydroxyalkanoates (PHA) production is growing since it allows to solve the main concerns about their disposal and simultaneously to recover added-value products. A pilot scale platform has been designed for this purpose. The VFA-rich fermentation liquid coming from the anaerobic treatment of both source-sorted organic fraction of municipal solid waste (OFMSW) and waste activated sludge (WAS) has been used as substrate for the aerobic process steps: a first sequencing batch reactor (SBR, 100 L) for the selection of a PHA-producing biomass, and a second fed-batch reactor (70 L) for PHA accumulation inside the cells. The SBR was operated at 2.0-4.4 kg COD/(m3 d) as OLR, under dynamic feeding regime (feast-famine) and short hydraulic retention time (HRT; 1 day). The selected biomass was able to accumulate up to 48% g PHA/g VSS. Both steps were performed without temperature (T) control, avoiding additional consumption of energy. In this regard, the applied OLR was tuned based on environmental T and, as a consequence, on biomass kinetic, in order to have a constant selective pressure. The latter was mainly quantified by the PHA storage yield (YP/Sfeast 0.34-0.45 CODP/CODS), which has been recognized as the main parameters affecting the global PHA productivity [1.02-1.82 g PHA/(L d)] of the process.
中文翻译:
温度对食物垃圾和污水污泥转化为聚羟基链烷酸酯的混合培养中试规模好氧过程的影响。
城市有机废物作为聚羟基链烷酸酯 (PHA) 生产原料的利用正在增长,因为它可以解决对其处置的主要问题,同时回收增值产品。为此目的设计了一个中试规模的平台。来自城市固体废物源分选有机部分 (OFMSW) 和废弃活性污泥 (WAS) 厌氧处理的富含 VFA 的发酵液已用作好氧工艺步骤的底物:第一个序批式反应器 (SBR) , 100 L) 用于选择产生 PHA 的生物质,第二个补料分批反应器 (70 L) 用于细胞内 PHA 的积累。SBR 在 2.0-4.4 kg COD/(m 3d) 作为 OLR,在动态喂养制度(盛宴 - 饥荒)和短水力停留时间(HRT;1 天)下。所选生物质能够积累高达 48% g PHA/g VSS。两个步骤都在没有温度 (T) 控制的情况下进行,避免了额外的能量消耗。在这方面,应用的 OLR 是根据环境 T 和因此根据生物质动力学进行调整的,以便具有恒定的选择压力。后者主要通过PHA储存产量(Y P/S盛宴0.34-0.45 COD P /COD S)量化,已被公认为影响全球PHA生产力的主要参数[1.02-1.82 g PHA/(L d) ] 的过程。