Интенсификация производства газообразных носителей водорода за счет применения электролизной ячейки в системе двухстадийного анаэробного сбраживания

Анаэробное сбраживание (АС) представляет собой перспективный метод получения биогаза из органических отходов. Перспективным направлением исследования является двухстадийное анаэробное сбраживание, в процессе которого возможно одновременное получение водорода и биогаза. Однако внедрение данного процесса ограничено ввиду низкой скорости и эффективности процесса, поэтому одной из стратегий является использование микробной электролизной ячейки (МЭЯ), которая позволяет улучшить конверсию субстрата в биогаз. В данной работе было исследовано влияние приложенного напряжения (0; 1,2 и 2,4 В) на интенсивность продукции метана при двухстадийном АС модели жидких органических отходов, предобработанных в аппарате вихревого слоя (АВС). В результате, наибольший объемный выход биометана 0,151 ± 0,071 л/(л·ч) был получен при разнице потенциалов на электродах МЭЯ 1,2 В. В процессе эксперимента энергетический вклад темновой ферментации в общий объемный энергетический выход составлял 58,81-66,2%, при этом наименьшее значение 58,81% было получено при напряжении 1,2 В. Наименьшая концентрация растворимых продуктов метаболизма 0,59 г/л в метаногенном реакторе также наблюдалась при разнице потенциалов 1,2 В. В микробном сообществе ацидогенного реактора DF основным продуцентом водорода был род Thermoanaerobacterium (54,80-84,58%). В реакторе MF под воздействием напряжения 1,2 В происходило обогащение сообщества гидрогенотрофными метаногенами рода Methanothermobacter и водород-продуцирующих родов Thermanaerovibrio, Cloacimonadaceae W5, Acetomicrobium, Coprothermobacter. Таким образом применение микробной электролизной ячейки с разницей потенциалов 1,2 В позволяет повысить энергетический выход системы двухстадийного анаэробного сбраживания предобработанной в АВС модели пищевых отходов на 33%.

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