Simoes Francisco, Vale Peter, Stephenson Tom, Soares Ana
a Cranfield Water Science Institute , Cranfield University , Cranfield , UK.
b Technology and Development , Severn Trent Water Ltd. , Coventry , UK.
Environ Technol. 2018 Sep;39(17):2278-2287. doi: 10.1080/09593330.2017.1411399. Epub 2017 Dec 21.
Biological struvite (bio-struvite) production through biomineralization has been suggested as an alternative to chemically derived struvite production to recover phosphorus from wastewater streams. In this study, statistical experimental design techniques were used to find the optimal growth rate (μ) of Brevibacterium antiquum in sludge liquors. Acetate, oleic acid, NaCl, NH-N, and Ca were shown to affect the growth rate of B. antiquum. The growth rate reached 3.44 1/d when the bacteria were supplemented with 3.0% w/v NaCl and 1124 mg chemical oxygen demand/L as acetate. However, NaCl was found to hinder the biomineralization of bio-struvite. A two-stage experiment demonstrated that bio-struvite was produced in the presence of acetate. Bio-struvite production was confirmed with X-ray spectroscopy and crystal morphology (prismatic, tabular, and twinned crystal habit) through electron microscope analysis. The bio-struvite production was estimated by measuring phosphate content of the recovered precipitates, reaching 9.6 mg P/L as bio-struvite. Overall, these results demonstrated the optimal conditions required to achieve high growth rates as well as bio-struvite production with B. antiquum. The results obtained in this study could be used to develop a process to grow B. antiquum in wastewater streams in mixed cultures and recover phosphorus-rich products such as struvite.
通过生物矿化生产生物鸟粪石（bio-struvite）被认为是一种替代化学合成鸟粪石生产的方法，用于从废水流中回收磷。在本研究中，采用统计实验设计技术来寻找古老短杆菌（Brevibacterium antiquum）在污泥液中的最佳生长速率（μ）。结果表明，乙酸盐、油酸、氯化钠、氨氮和钙会影响古老短杆菌的生长速率。当向细菌中添加3.0% w/v的氯化钠和1124 mg化学需氧量/L的乙酸盐作为碳源时，生长速率达到3.44 1/d。然而，发现氯化钠会阻碍生物鸟粪石的生物矿化。两阶段实验表明，在乙酸盐存在的情况下会产生生物鸟粪石。通过X射线光谱分析和电子显微镜分析晶体形态（棱柱形、板状和孪晶习性）证实了生物鸟粪石的产生。通过测量回收沉淀物中的磷含量来估算生物鸟粪石的产量，达到9.6 mg P/L的生物鸟粪石。总体而言，这些结果表明了实现古老短杆菌高生长速率以及生物鸟粪石生产所需的最佳条件。本研究获得的结果可用于开发一种在混合培养的废水流中培养古老短杆菌并回收富含磷的产品（如鸟粪石）的工艺。
