The Role of CFD in Validating Scrubber Technology

SYNOPSIS

The International Maritime Organization (IMO) regulates pH discharge limits for ocean-going vessels with onboard Sulfur Dioxide (SO2) exhaust abatement technology (SOx scrubbers). Typically, scrubbers generate a slightly acidic washwater that is occasionally discharged overboard while at sea. Because discharge levels that are too acidic may harm nearby marine life, the IMO limits pH levels within a 4 meter radius of the overboard discharge port FMSI’s role is to ensure their customer’s onboard scrubber systems, including the overboard washwater discharge system, are in compliance with regulation. Shipbuilders must demonstrate that their vessels are in compliance with the pH discharge limits set by the IMO through simulation with a high-fidelity CFD model or direct measurement in the field.

By utilizing CFD simulations and consulting from Resolved Analytics, FMSI is able to predict the dilution rates of the washwater at the target distance from the vessel for various flow scenarios and port designs. When dilution rates are not achieved with simple port designs alone, complex diffuser inserts can be added into the flow stream to aid in downstream mixing and dilution. Coupled with Resolved Analytics’ optimization and design experience, the high-fidelity CFD modeling allows for port diffuser geometry to be optimized quickly and cost effectively, providing increased effluent stream dilution while limiting excessive system pressure drop---as contrasted with an experimental build-and-test technique.

VALUES/HIGHLIGHTS

FMSI Services utilizes the benefits of CFD analysis to validate their vessel scrubber technology for customers and sea going vessels around the world.

CFD analysis is allowing FMSI Services to create compliant scrubber and effluent handling systems for their vessels by ensuring their designs meet pH dilution requirements prior to leaving port.