Amount of H₂S and SO₂ were generated during the SCWG of sewage sludge. It is essential to reduce the sulfur concentration in syngas for depth utilization of syngas from SCWG of sewage sludge. The syngas desulfurization ability of five additives (KOH, K₂CO₃, NaOH, Na₂CO₃, AC) were tested and the result indicated that K₂CO₃ had the best syngas desulfurization effect while KOH could significantly promote the yield of syngas at 450 °C and 4% loading. Increasing KOH and K₂CO₃ loading to 12% could reduce around 90% of sulfur in syngas comparing to no additives. The XPS analysis results indicated that alkali additives promoted the cyclization and oxidation of unstable sulfur compounds in raw sludge, which can convert it into stable sulfur compounds such as thiophene, sulfone and sulfate. The sulfur in liquid was mainly in the forms of sulfate, and the effect of alkali and AC additive on sulfur in liquid was relatively weak.

在污水污泥的SCWG期间产生了一定量的H ₂ S和SO ₂。降低合成气中的硫浓度对于污水污泥超临界水处理合成气的深度利用至关重要。测试了五种添加剂（KOH、K ₂ CO ₃、NaOH、Na ₂ CO ₃、AC）的合成气脱硫能力，结果表明K ₂ CO ₃对合成气的脱硫效果最好，而KOH能显着提高合成气的收率在 450 °C 和 4% 负载下。增加 KOH 和 K ₂ CO ₃与没有添加剂相比，负载至 12% 可以减少合成气中约 90% 的硫。XPS分析结果表明，碱性添加剂促进了原料污泥中不稳定硫化合物的环化和氧化，使其转化为噻吩、砜和硫酸盐等稳定的硫化合物。液中硫主要以硫酸盐形式存在，碱和AC添加剂对液中硫的影响较弱。