Gielen Gerty J H P, Andrews John P, Karbiwnyk Christine M, Riddell Mark J C, Husheer Sean W, Gapes Daniel J
Scion, Titokorangi Drive, Private Bag 3020, Rotorua 3046, New Zealand.
Heliyon. 2022 Jun 13;8(6):e09708. doi: 10.1016/j.heliyon.2022.e09708. eCollection 2022 Jun.
Globally, many populations suffer from a lack of access to basic sanitation facilities. This is partly caused by a combination of water resource shortages and the high cost of conventional centralised treatment systems. A novel decentralised treatment technology based on sub-critical hydrothermal processing of organic wastes at toilet-scale, contributes to addressing these economic and resource limitations. To be effective, this technology needs to satisfy a broad range of environmental and safety considerations, including the nature and quantity of formed gas products. We investigated the impact of four process parameters (temperature; O: COD ratio (λ); time; feed solids content) on off-gas composition by quantifying volatile organic compounds (VOCs), CO, H and CO in factorial experiments. Temperature and λ influenced VOCs generation greatly. The lowest VOC emissions occurred at 200% λ and 300 °C. Aldehydes and ketones were mostly generated at 200% λ and intermediate temperatures, sulphur compounds in the absence of oxygen, and aromatics, furans, and pyrroles at intermediate oxygen levels and elevated temperatures. Most CO was created at 300 °C but its concentration decreased at longer processing times. Processing conditions have complex impacts and require careful consideration when designing for real world deployment.
在全球范围内，许多人群缺乏基本的卫生设施。部分原因是水资源短缺与传统集中式处理系统成本高昂共同作用的结果。一种基于厕所规模有机废物亚临界水热加工的新型分散式处理技术，有助于解决这些经济和资源限制问题。为有效发挥作用，该技术需要满足广泛的环境和安全考量，包括生成气体产物的性质和数量。我们通过在析因实验中对挥发性有机化合物（VOCs）、一氧化碳（CO）、氢气（H₂）和二氧化碳（CO₂）进行定量分析，研究了四个工艺参数（温度；氧与化学需氧量的比例（λ）；时间；进料固体含量）对废气成分的影响。温度和λ对VOCs的生成影响极大。在λ为200%且温度为300℃时，VOCs排放量最低。醛类和酮类大多在λ为200%及中等温度下生成，硫化合物在无氧条件下生成，而芳烃、呋喃和吡咯在中等氧含量及较高温度下生成。大部分CO在300℃时产生，但在较长处理时间下其浓度会降低。加工条件具有复杂的影响，在设计实际应用时需要仔细考虑。
