University of A Coruña Alejandro de la Sota, no 1, A Coruña 15008, Spain.
Water Sci Technol. 2010;62(10):2294-300. doi: 10.2166/wst.2010.949.
Fibreboard production is one of the most important industrial activities in Galicia (Spain). Great amounts of wastewater are generated, with properties depending on the type of wood, treatment process, final product and water reusing, among others. These effluents are characterized by a high chemical oxygen demand (COD), low pH and nutrients limitation. Aerobic and anaerobic processes have been used for their treatment. Presently, bioplastics production (mainly polyhydroxyalkanoates or PHA) from wastewaters with mixed cultures is being studied. Substrate requirements for these processes are a high organic matter content and low nutrient concentration. Therefore, wood mill effluents could be a suitable feedstock. PHA production from wastewaters is carried out in three steps. First, complex organic matter is converted into volatile fatty acids (VFA) through acidogenic fermentation. Then, VFA are used as substrate in an aerobic sequencing batch reactor (SBR), in which the enrichement of PHA producing bacteria from a mixed culture is favoured. Finally, the sludge from the SBR is fed with a pulse containing high VFA concentrations, resulting in PHA accumulation inside the cells. In this work, the possibility of applying this process to wood mill effluents is proposed. An acidification percentage of 37% and a storage yield (Y(STO)) of 0.23 Cmmol/Cmmol were obtained.
纤维板生产是加利西亚（西班牙）最重要的工业活动之一。会产生大量废水，其性质取决于木材类型、处理工艺、最终产品和水的再利用等。这些废水的特点是化学需氧量（COD）高、pH 值低且营养物质有限。已经使用好氧和厌氧工艺对其进行处理。目前，正在研究利用混合培养物从废水中生产生物塑料（主要是聚羟基烷酸酯或 PHA）。这些工艺的底物要求是高有机物含量和低营养浓度。因此，木材加工厂废水可能是合适的原料。PHA 是通过三步从废水中生产的。首先，通过产酸发酵将复杂的有机物转化为挥发性脂肪酸（VFA）。然后，VFA 被用作好氧序批式反应器（SBR）中的底物，在该反应器中，从混合培养物中富集产生 PHA 的细菌。最后，将 SBR 中的污泥与含有高 VFA 浓度的脉冲进料，导致细胞内 PHA 积累。在这项工作中，提出了将该工艺应用于木材加工厂废水的可能性。获得了 37%的酸化率和 0.23 的储存产率（Y(STO)）。
