Taheri Ensiyeh, Amin Mohammad Mehdi, Pourzamani Hamidreza, Fatehizadeh Ali, Ghasemian Mohammad, Bina Bijan
Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran.
Student Research Committee, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran.
J Med Signals Sens. 2018 Apr-Jun;8(2):101-107.
Hydrogen gas is the cleanest energy carrier and could be produced by biological process. Dark fermentation is one of the biohydrogen production methods that carried out just on organic wastes conversion.
In this study, the batch tests were conducted to compare the biohydrogen production and glucose fermentation via acetate-butyrate and acetate-ethanol metabolic pathway induced by NaOH and KOH (10 M) pretreatment. In batch test, the glucose concentration in the feed was varied from 3.75 to 15 g/L under mesophilic conditions (37°C ± 1°C). In order to sludge pretreatment, NaOH and KOH (as an alkaline agent) was used.
Batch tests showed that maximum biohydrogen production under NaOH (2.7 ± 0.5 L) and KOH (2.2 ± 0.7 L) pretreatment was achieved at 15 g/L of influent glucose. In the batch test, with increasing influent glucose concentration, the lower yields of hydrogen were observed. The biohydrogen reactions had good electron closure (5.2%-13.5%) for various glucose concentrations and pretreatments. For NaOH and KOH pretreatment, the biohydrogen yield decreased from 2.49 to 1.63 and from 2.22 to 1.2 mol H/mol glucose, respectively, when glucose concentration increased from 3.75 to 15 g/L.
By applying alkaline sludge pretreatment by NaOH and KOH, the glucose fermentation was followed with acetate-butyrate and acetate-ethanol metabolic pathway, respectively. The lower biohydrogen yields were observed under acetate-ethanol metabolic pathway and related to metabolically unfavorable for biohydrogen production.
氢气是最清洁的能量载体，可通过生物过程产生。暗发酵是仅基于有机废物转化的生物制氢方法之一。
在本研究中，进行了批次试验，以比较通过NaOH和KOH（10 M）预处理诱导的乙酸 - 丁酸和乙酸 - 乙醇代谢途径进行的生物制氢和葡萄糖发酵。在批次试验中，进料中的葡萄糖浓度在中温条件（37°C ± 1°C）下从3.75变化至15 g/L。为了进行污泥预处理，使用了NaOH和KOH（作为碱性试剂）。
批次试验表明，在进水葡萄糖浓度为15 g/L时，NaOH（2.7 ± 0.5 L）和KOH（2.2 ± 0.7 L）预处理下实现了最大生物制氢量。在批次试验中，随着进水葡萄糖浓度的增加，观察到氢气产量降低。对于各种葡萄糖浓度和预处理，生物制氢反应具有良好的电子封闭性（5.2% - 13.5%）。对于NaOH和KOH预处理，当葡萄糖浓度从3.75增加到15 g/L时，生物制氢产率分别从2.49降至1.63和从从2.22降至1.2 mol H/mol葡萄糖。
通过应用NaOH和KOH进行碱性污泥预处理，葡萄糖发酵分别遵循乙酸 - 丁酸和乙酸 - 乙醇代谢途径。在乙酸 - 乙醇代谢途径下观察到较低的生物制氢产率，这与对生物制氢代谢不利有关。
