Sub-Department of Environmental Technology, Wageningen University, Wageningen, The Netherlands.
Water Res. 2013 Jul 1;47(11):3742-51. doi: 10.1016/j.watres.2013.04.028. Epub 2013 May 3.
Autogenerative High Pressure Digestion (AHPD) is a novel concept that integrates gas upgrading with anaerobic digestion by selective dissolution of CO2 at elevated biogas pressure. However, accumulation of CO2 and fatty acids after anaerobic digestion of glucose resulted in pH 3-5, which is incompatible with the commonly applied high-rate methanogenic processes. Therefore, we studied the use of wollastonite, olivine and anorthosite, with measured composition of CaSi1.05O3.4, Mg2Fe0.2Ni0.01Si1.2O5.3 and Na0.7Ca1K0.1Mg0.1Fe0.15Al3.1Si4O24, respectively, to scavenge CO2 during batch AHPD of glucose. Depending on the glucose to mineral ratio the pH increased to 6.0-7.5. Experiments with wollastonite showed that Ca(2+)-leaching was caused by volatile fatty acid (VFA) production during glucose digestion. At 1, 3 and 9 bar, the CH4 content reached 74%, 86% and 88%, respectively, indicating CO2 scavenging. Fixation of produced CO2 by CaCO3 precipitation in the sludge was confirmed by Fourier Transferred-InfraRed, Combined Field emission Scanning Electron Microscopy-Energy-dispersive X-ray spectroscopy and Thermogravimetric Analysis-Mass Spectroscopy.
自生高压消化（AHPD）是一种将气体升级与厌氧消化相结合的新概念，通过在沼气高压下选择性溶解 CO2 来实现。然而，在葡萄糖的厌氧消化后，CO2 和脂肪酸的积累导致 pH 值为 3-5，这与常用的高速产甲烷过程不兼容。因此，我们研究了使用硅灰石、橄榄石和斜长石来吸收 CO2，它们的组成分别为 CaSi1.05O3.4、Mg2Fe0.2Ni0.01Si1.2O5.3 和 Na0.7Ca1K0.1Mg0.1Fe0.15Al3.1Si4O24。在葡萄糖的批处理 AHPD 中，根据葡萄糖与矿物的比例，pH 值增加到 6.0-7.5。硅灰石实验表明，Ca（2+）的浸出是由葡萄糖消化过程中挥发性脂肪酸（VFA）的产生引起的。在 1、3 和 9 巴下，CH4 含量分别达到 74%、86%和 88%，表明 CO2 被吸收。污泥中 CaCO3 沉淀固定产生的 CO2 通过傅里叶变换红外光谱、组合场发射扫描电子显微镜-能谱和热重分析-质谱得到了证实。
