Long-term performance and microbial community analysis of a full-scale synthesis gas fed reactor treating sulfate- and zinc-rich wastewater.

The performance of a full-scale (500 m3) sulfidogenic synthesis gas fed gas-lift reactor treating metal- and sulfate-rich wastewater was investigated over a period of 128 weeks. After startup, the reactor had a high methanogenic activity of 46 Nm3.h(-1).

Desulfovibrio paquesii sp. nov., a hydrogenotrophic sulfate-reducing bacterium isolated from a synthesis-gas-fed bioreactor treating zinc- and sulfate-rich wastewater.

A hydrogenotrophic, sulfate-reducing bacterium, designated strain SB1(T), was isolated from sulfidogenic sludge of a full-scale synthesis-gas-fed bioreactor used to remediate wastewater from a zinc smelter. Strain SB1(T) was found to be an abundant micro-organism in the sludge at the time of isolation. Hydrogen, formate, pyruvate, lactate, malate, fumarate, succinate, ethanol and glycerol served as electron donors for sulfate reduction.

Occurrence of methanogenesis during start-up of a full-scale synthesis gas-fed reactor treating sulfate and metal-rich wastewater.

The start-up of a full-scale synthesis gas-fed gas-lift reactor treating metal and sulfate-rich wastewater was investigated. Sludge from a pilot-scale reactor was used to seed the full-scale reactor. The main difference in design between the pilot- and full-scale reactor was that metal precipitation and sulfate reduction occurred in the same reactor.