Anaerobic Hydrogen Production from Sucrose Using an Acid‐Enriched Sewage Sludge Microflora

Abstract

A novel and high-rate anaerobic sequencing bath reactor (ASBR) process was used to evaluate the hydrogen productivity of an acid-enriched sewage sludge microflora at a temperature of 35 C. In this ASBR process a 4 h cycle, including feed, reaction, settle, and decant steps, was repeatedly performed in a 5 L reactor. The sucrose substrate concentration was 20 g COD/L; the hydraulic retention time (HRT) was maintained at 12±120 h at the initial period and thereafter at 4±12 h. The reaction/settle period ratio, which is the most important parameter for ASBR operation was 1.7. The experimental results indicated that the hydrogenic activity of the sludge microflora was HRT-dependent and that proper pH control was necessary for a stable operation of the bioreactor. The peak hydrogenic activity value was attained at an HRT of 8 h and an organic loading rate of 80 kg COD/ m 3 day. Each mole of sucrose in the reactor produced 2.8 mol of hydrogen and each gram of biomass produced 39 mmol of hydrogen per day. An overly-short HRT might deteriorate the hydrogen productivity. The concentration ratios of butyric acid to acetic acid, as well as volatile fatty acid and soluble microbial products to alkalinity can be used as monitoring indicators for the hydrogenic bioreactor.

Continuous dark fermentative hydrogen production by mesophilic microflora: Principles and progress

“…The volumetric production rate and specific H 2 production rates from the sequencing batch reactor were comparable with CSTR values, while the upper value of VSS was higher (Table 3). Lin and Chou [34] using the same sequencing batch system report the high alkalinities occurring (> 6 g l −1 as CaCO 3 ), presumably due to operation at pH 6.7. This may give rise to problems of alkali consumption in the overall process.…”

“…Inocula are commonly pretreated to select for spore formers and destroy methanogens. Lin and Chou [34] investigated acid treatment (pH 3-4 with HCl for 24 h) of waste activated sludge from a municipal sewage treatment works. This inoculum has been used to develop the carrier-induced granular sludge bed reactor [35,36].…”

Kinetic Model of Thermophilic Biohydrogen Production from POME

“…Even though the latter approach is convenient in evaluating the overall process performance, it is challenging to use VS or COD as a gross substrate. In addition, not all portion of VS or COD is available to the substrate and microbes [27]. In this study, total carbohydrate (TC) in the reactor is used as the rate-limiting substrate.…”

“…The value of B0 varies with temperature and type of substrate and manure. It was found that the value of B0 depends on the age of the manure, species, collection and storage, ration, and bedding material [23,27].…”

“…Chen et al [27] developed a kinetic model on substrate utilization based on the Contois model. The kinetic model has been mostly applied in many research, particularly in studies on AD of high strength wastes [34,35].…”