Développement d'un système de contrôle de paramètres biologiques d'un bioprocédé de désulfurisation basé sur des indicateurs métabolomiques

企业EBIénergie(EBI)将从垃圾填埋池收集的沼气转化为可再生天然气(RNG)。沼气中的硫化氢含量很高，企业必须分两个阶段进行脱除。第一阶段是生物脱硫过程，将硫化氢浓度从平均1500ppm降至30ppmv左右。在第二个化学吸附阶段，EBI对沼气进行抛光，以达到必须注入天然气管道的质量。两年前，由于原料沼气中的硫化氢含量从历史上的400ppmv意外增加到1500ppmv，EBI启动了生物脱硫工艺。最后的浓度保持稳定，EBI有义务安装一个预处理装置，以降低沼气升级的运营成本。运行良好的生物脱硫工艺具有较高的脱硫率。除微生物参数外，生物过程几乎完全自动化。企业希望开发生物指标，如代谢因子，让人们了解微生物种群的良好状态。这对于EBI来说是非常重要的，因为企业有义务停止生物过程，因为吸附塔填充床中积累的元素硫和生物量堵塞了床。停止这一生物过程对EBI来说意味着高昂的费用，因为在更换包装材料的过程中，必须燃烧未经处理的沼气。该项目的结果将使确定与主要指标挂钩的运行参数的莱特区和错误区。纠正指标偏差的措施将在实验室规模进行测试。这将有助于制定协议，使生物过程在稳健和稳定的运行模式下运行。

The enterprise EBI Énergie (EBI) converts biogas collected from landfill cells into renewable natural gas (RNG). The biogas has high H2S content and the enterprise must remove it in two phases. The first phase is a biological desulphurization process which decrease the H2S concentration from an average of 1500 ppm to around 30 ppmv. In a second chemical adsorption phase, EBI polishes the biogas to reach the quality which must have to be injected in a gas pipeline. EBI started up the operation of biological desulphurization process two years ago due to an unexpected increase of H2S in raw biogas from historical 400 ppmv to up to 1500 ppmv. The last concentration stayed stable and EBI was obligated to install a pretreatment unit to decrease operating costs for biogas upgrading. The biological desulphurization process presents high removal efficiency if it is well operated. The bioprocess is almost completely automated, except for microbiological parameters. The enterprise would like to develop biological indicators, such as metabolomic factors, which let to know the good state of microbial population. This is very important for EBI because the enterprise was obligated to stop the bioprocess due to accumulation of elementary sulfur and biomass in the packed bed of adsorption tower which clogged the bed. The stop of this bioprocess represents high expenses for EBI, because must flare the untreated biogas during the changing of packing material. The results of this project will let to determine the wright and wrong regions for operating parameters linked with main indicators. Measures to correct deviations of indicators will be tested at laboratory scale. This will be helpful to develop protocols to operate the bioprocess under robust and stable operating mode.