RePower Humboldt: BLR Biomass Facility Ventilation System Design Complete

Model of syngas concentration 5 minutes after a leak with the original (top) and final (bottom) ventilation designs. The pink areas are the zones where the concentration is immediately dangerous due to CO toxicity.

Models of syngas concentrations five minutes after a leak with the original (top) and final (bottom) ventilation designs. The pink areas are the zones where the concentration is immediately dangerous due to CO toxicity.

Last summer, the RePower team began evaluating the proposed ventilation system for the Blue Lake Rancheria (BLR) biomass energy facility. Each phase of the BLR gasification process involves a dangerous gas. First, biomass is processed into a syngas rich in hydrogen and carbon monoxide. This syngas is then processed into pure hydrogen and a waste gas rich in carbon monoxide. In normal operation, the syngas and hydrogen are fully contained, and the waste gas is safely burned in a flare. However, an accidental leak in the system could pose an immediate toxic or explosive danger. The ventilation system must give personnVentilation_Image_2el enough time to safely exit, and must clear hazardous gases from the building after the gasifier system shuts down.

To test different system designs, the RePower team used a software package from the National Institute of Standards and Technology to model contaminant flow in 3-D. We simulated various leak scenarios and examined how the placement of exhaust fans and intake vents affected the removal of toxic and flammable gases. We were able to improve on the original system design and create a more responsive, and robust system. The final design uses a combination of ceiling fans, wall fans, and floor vents to provide optimum ventilation. Following installation, the ventilation system will undergo a smoke test to validate the model results. Completion of this work will ensure a safe operating environment for the biomass facility.