Effect of carbonate on anaerobic acidogenesis and fermentative hydrogen production from glucose using leachate as supplementary culture under alkaline conditions.

Carbonate was added into a co-culture of glucose and fresh leachate under alkaline condition to enhance batched acidogenesis and fermentative hydrogen production simultaneously. Results indicated carbonate has positive effect on both H(2) production and acetic acid generation. The highest hydrogen yield (about 1.40 mol/mol glucose) was obtained at [CO(3)(2-)] = 280 mg/L with pH 8.0 and [CO(3)(2-)] = 560 mg/L with pH 9. The dominant liquid metabolites were ethanol, acetic and butyric acid. The highest total volatile fatty acid yield (0.38 g/g glucose) was achieved at [CO(3)(2-)] = 560 mg/L with pH 9. In this case, the acetic acid yield reached 0.13 g/g glucose. Verification tests using simulated wastewater as substrate were also carried out at pH 9. Results demonstrated calcium ions inhibit hydrogenogens activity while carbonate addition can alleviate the suppression effect caused by Ca(2+).

[Removal of odors from fermentation process of MSW biological mechanical treatment using compost biofilter].

For the odour from fermentation processing of municipal solid waste biological mechanical treatment, a compost biofilter was established to investigate its performance and the characteristics change of compost. The component and TVOC concentration in odors, removal efficiency of biofilter, and total carbon (TC), total nitrogen (TN), total phosphorus (TP), organic matter (OM), pH value and bacterial colony in compost media were measured respectively. SPME-GC-MS analysis showed that the main components of odors were BTEX, terpenes and alkane. The range of TVOC concentrations in odors during a fermentation process period and removal efficiencies of biofilter were 68.3 x 10(-6) -3.3 x 10(-6) (volume fraction), 31.5%-84.8% respectively. After about 4 months operation, TN, TC, TP and OM in compost were kept almost stably, but the dissolved N experienced an increase of 53.7%, and the dissolved P decreased 19.6%. The pH value experienced an increase in the former period and kept stable finally at about 7.8, which excursion was from 7.49 to 7.86. Analytical results for bacterial colony in packing material indicated that bacteria and mould colony counts increased, but yeasts and actinomyces decreased along with biofilter operation, which were 3.1, 3.4, 0.04, 0.07 times of their initial values respectively.