Linville Jessica L, Shen Yanwen, Ignacio-de Leon Patricia A, Schoene Robin P, Urgun-Demirtas Meltem
Argonne National Laboratory, Energy Systems Division, Lemont, IL, USA.
Waste Manag Res. 2017 Jun;35(6):669-679. doi: 10.1177/0734242X17704716. Epub 2017 May 10.
A modified version of an in-situ CO removal process was applied during anaerobic digestion of food waste with two types of walnut shell biochar at bench scale under batch operating mode. Compared with the coarse walnut shell biochar, the fine walnut shell biochar has a higher ash content (43 vs. 36 wt%) and higher concentrations of calcium (31 vs. 19 wt% of ash), magnesium (8.4 vs. 5.6 wt% of ash) and sodium (23.4 vs. 0.3 wt% of ash), but a lower potassium concentration (0.2 vs. 40% wt% of ash). The 0.96-3.83 g biochar (g VS) fine walnut shell biochar amended digesters produced biogas with 77.5%-98.1% CH content by removing 40%-96% of the CO compared with the control digesters at mesophilic and thermophilic temperature conditions. In a direct comparison at 1.83 g biochar (g VS), the fine walnut shell biochar amended digesters (85.7% CH content and 61% CO removal) outperformed the coarse walnut shell biochar amended digesters (78.9% CH content and 51% CO removal). Biochar addition also increased alkalinity as CaCO from 2800 mg L in the control digesters to 4800-6800 mg L, providing process stability for food waste anaerobic digestion.
在间歇操作模式下的实验室规模，采用一种改良的原位CO去除工艺，用两种核桃壳生物炭处理食物垃圾的厌氧消化过程。与粗核桃壳生物炭相比，细核桃壳生物炭具有更高的灰分含量（43%对36%重量）以及更高浓度的钙（占灰分的31%对19%重量）、镁（占灰分的8.4%对5.6%重量）和钠（占灰分的23.4%对0.3%重量），但钾浓度较低（占灰分的0.2%对40%重量）。在中温和高温条件下，添加0.96 - 3.83克生物炭（每克挥发性固体）的细核桃壳生物炭改良消化器，通过去除40% - 96%的CO，产生了CH含量为77.5% - 98.1%的沼气，与对照消化器相比。在1.83克生物炭（每克挥发性固体）的直接比较中，细核桃壳生物炭改良消化器（CH含量85.7%，CO去除率61%）优于粗核桃壳生物炭改良消化器（CH含量78.9%，CO去除率51%）。添加生物炭还使碱度从对照消化器中的2800毫克/升碳酸钙增加到4800 - 6800毫克/升，为食物垃圾厌氧消化提供了工艺稳定性。
