College of Environmental Science and Engineering, Hunan University, Changsha, People's Republic of China.
Waste Manag Res. 2013 Apr;31(4):393-400. doi: 10.1177/0734242X12471097. Epub 2013 Jan 11.
Digested sewage sludge gasification in supercritical water was studied. Influences of main reaction parameters, including temperature (623-698 K), pressure (25-35 Mpa), residence time (10-15 min) and dry matter content (5-25 wt%), were investigated to optimize the gasification process. The main gas products were methane, carbon monoxide, carbon dioxide and traces of ethene, etc. Results showed that 10 wt% dry matter content digested sewage sludge at a temperature of 698 K and residence time of 50 min, with a pressure of 25 MPa, were the most favorable conditions for the sewage sludge gasification and carbon gasification efficiencies. In addition, potassium carbonate (K2CO3) was also employed as the catalyst to make a comparison between gasification with and without catalyst. When 2.6 g K2CO3 was added, a gasification efficiency of 25.26% and a carbon gasification efficiency of 20.02% were achieved, which were almost four times as much as the efficiencies without catalyst. K2CO3 has been proved to be effective in sewage sludge gasification.
研究了消化污泥在超临界水中的气化。考察了主要反应参数，包括温度（623-698 K）、压力（25-35 MPa）、停留时间（10-15 min）和干物质含量（5-25 wt%）对气化过程的影响，以优化气化工艺。主要气体产物有甲烷、一氧化碳、二氧化碳和微量的乙烯等。结果表明，在温度为 698 K、停留时间为 50 min、压力为 25 MPa 的条件下，10 wt%干物质含量的消化污泥是最有利于污泥气化和碳气化的条件。此外，还采用碳酸钾（K2CO3）作为催化剂，比较了有催化剂和无催化剂条件下的气化效果。当添加 2.6 g K2CO3 时，气化效率达到 25.26%，碳气化效率达到 20.02%，几乎是无催化剂时的四倍。实验证明 K2CO3 对污泥气化是有效的。
