PR-312-12208-R02 Limitations and Costs Associated with Raising Existing RICE Stack Heights

Modeling of actual and hypothetical compressor station facilities concluded increasing reciprocating engine stack height as one potential mitigation measure to reduce modeled impacts below the primary 1-hour NO2 National Ambient Air Quality Standards (NAAQS). Increasing stack heights to between 50-75 feet appears to offer considerable relief based on typical facility configurations (e.g., compressor house height, stack parameters). This white paper discusses potential stack design criteria to be considered when increasing existing exhaust stack heights or planning considerations for new units. To assist in gathering information on practical concerns and issues associated with raising existing compressor driver stacks, a questionnaire was developed and provided to operations and engineering staff, OEMs, and members to provide insight into physical constraints, engineering considerations, and costs to be considered and evaluated in developing this report. This white paper summarizes stack height limitations for reciprocating engines based on operating (e.g., back pressure, effective stack heights) and physical (e.g., guy-wire and structural requirements) constraints. Where available, cost implications are also provided. Criteria addressed include: Good Engineering Practice (GEP) for stack heights, engine back pressure limitations, structural integrity of the exhaust system, wind and seismic loads on the exhaust stack, and other specifications for structural designs. Proper stack design should address local environmental regulations, local building codes (e.g., height requirements, wind and seismic loads), structural integrity, base configuration, and lateral support.