Hyperion Wastewater Capital Improvement Project, HSHDigester Gas Handling Project – City of Los Angeles, Bureau of Sanitation



City of Los Angeles Department of Public Works Bureau of Sanitation


Piping Design; Structural Engineering; CADD Operation; Cost Estimating; Start-up support; Construction Management

De-sulfurization Plant Modifications: DRC investigated the H2S Removal Facility to identify operational problems and recommended modifications. Our team also investigated alternate H2S removal processes and pilot-tested as substitutes for the existing vanadium based Stretford process. These modifications to the de-sulfurization plant consisted of piping and certain equipment that alleviated operational problems and converted the process technology from Stretford to Lo Catiron-based technology. Additionally, this project maximized the plants operational mode by increasing the treatment capacity of the plant to 12 million Standard Cubic Feet per Day (SCFD). This also increased the sulfur removal efficiency, which complied with Air Quality Management District (AQMD) Rule 431.1. It also provided redundancy to those items that required plant shutdowns for maintenance and upgraded the emission control system to a state-of-the-art bio-filter system. De-sulfurization Plant Expansion: Based on criteria developed tested and noted above, the de-sulfurization capacity was expanded to handle the treatment of projected increases in digester gas. The expansion of the existing H2S Removal System provided an additional train capable of processing 20 million Standard Cubic Feet per Day (SCFD) of digester gas. DRC prepared Concept/Pre-design Reports and provided detailed design, construction management, and start-up support for the recommended modifications. DRC tested the completed facilities for compliance with the conditions of the AQMD permit. Gas Flare Expansion: As gas quantities increase, additional gas flares were required to accommodate gas handling during emergency conditions, emphasizing low noise levels and smokeless burner design. The expanded facility provided adequate spare capacity to accommodate the forecast digester production rate.