Abstract The presence of sulfur-based substances in the biogas (sour) produced from the digestion plant imposes several treatments to match the market and regulation requirements. Besides, it lays the production plants open to safety and environmental risks related to the accidental release of toxic species. This work is devoted to the investigation of the consequences of the accidental release of biogas containing hydrogen sulfide up to 10 %vol. To this aim, a schematic 3-D representation of a biogas productive plant was developed and implemented in a Computational Fluid Dynamics (CFD) model. The effects of the initial composition and the wind velocity on the cloud dispersion were evaluated. The calculated stand-off distances for lethality resulted from the numerical simulation were compared with the results of standard integral models commonly adopted in the process industry. Results indicated the dramatic effects of the toxicity of hydrogen sulfide on the downwind safety distance in the case of accidental release of sour biogas, and the negligible effects for the flammability concerns.

中文翻译：

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消化装置中酸性沼气的安全距离

摘要 消化装置产生的沼气（酸）中存在硫基物质，需要进行多种处理以符合市场和法规要求。此外，它还使生产工厂面临与有毒物种意外释放相关的安全和环境风险。这项工作致力于调查含有高达 10%vol 的硫化氢的沼气意外释放的后果。为此，在计算流体动力学 (CFD) 模型中开发并实施了沼气生产厂的 3D 示意图。评估了初始成分和风速对云扩散的影响。将数值模拟得出的致死率计算距离与过程工业中普遍采用的标准积分模型的结果进行比较。结果表明，在酸性沼气意外释放的情况下，硫化氢的毒性对顺风安全距离的显着影响，而对可燃性问题的影响可以忽略不计。