ABSTRACT

Biohydrogen produced from agricultural waste through dark co-fermentation is an increasingly valuable source of renewable energy. Rice straw (RS) and pig manure (PM) are widely available waste products in Asia with complementary levels of carbon and nitrogen that together have a high biohydrogen production potential. However, no research has yet determined the ideal inoculum pretreatment method and mixing ratio for biohydrogen production using these resources. In this study, we tested biohydrogen production using three different inoculum pretreatment methods (acid, alkali and thermal) at five RS/PM ratios (1:0, 5:1, 3:1, 1:1 and 0:1, based on total solids). All three pretreatments promoted biohydrogen production with the increase of bioactivity of biohydrogen-producing organisms (compared with a control group), though acid was clearly superior to thermal or alkali. Using acid pretreatment and RS/PM ratio of 5:1 corresponded with a relatively low ${\mathrm{N}\mathrm{H}}_4^{+}$-N concentration (655.17 mg/L), a maximal cumulative biohydrogen production of 44.59 mL/g VS_added with a low methane production (<0.1%), a large butyric acid accumulation (1035.30 mg/L) and a biohydrogen conversion rate of 2.12%. The optimal pH for biohydrogen production from co-fermentation of RS and PM ranged from 5.0–5.5.

摘要

通过黑暗共发酵从农业废物中生产的生物氢是一种越来越有价值的可再生能源。稻草 (RS) 和猪粪 (PM) 是亚洲广泛使用的废物产品，具有互补的碳和氮水平，共同具有很高的生物制氢潜力。然而，目前还没有研究确定利用这些资源生产生物制氢的理想接种物预处理方法和混合比例。在本研究中，我们使用三种不同的接种物预处理方法（酸、碱和热）以五种 RS/PM 比（1:0、5:1、3:1、1:1 和 0:1，基于总固体）。所有三种预处理都促进了生物氢的产生，生物产氢生物的生物活性增加（与对照组相比），尽管酸明显优于热或碱。使用酸预处理和 RS/PM 比为 5:1 对应相对较低的${\mathrm{N}\mathrm{H}}_4^{+}$-N 浓度 (655.17 mg/L)，最大累积生物氢产量 44.59 mL/g VS_添加低甲烷产量 (<0.1%)，大量丁酸积累 (1035.30 mg/L) 和生物氢转化率2.12%。由 RS 和 PM 共同发酵生产生物氢的最佳 pH 值范围为 5.0-5.5。