In a situation where a well cannot be capped, MWCC creates a closed loop system to contain well fluids using extended flowback equipment. The extended flowback system is tailored to site specific requirements including water depth, seafloor landscape, well flow rates, ocean currents and debris field. In this scenario, MWCC would still install the capping stack but rather than shutting off the flow, a series of flexible pipes, or flowlines, are linked to the capping stack which then route well fluids up to a Modular Capture Vessel (MCV) at the surface.
Deepwater drilling in the U.S. Gulf of Mexico is defined as 500 to 10,000 feet of water. This is a broad range which requires MWCC’s extended flowback system to be adaptable. In an incident at water depths of 500 to 2,000 feet, MWCC uses lazy-wave risers to hook the capping stack up to the capture vessels. A lazy wave configuration is a simple flowback solution that utilizes buoyancy and is attached to flexible pipes used to move fluid from the well to the ship. In water depths above 2,000 feet, MWCC uses a free standing riser to hook the capping stack up to the capture vessels. A free-standing riser is a series of vertical pipes that are connected and suspended in the water from the seafloor using giant buoyancy cans.
MWCC has two dedicated tanker vessels called Modular Capture Vessels (MCV). MCVs are standard oil tankers customized to process and capture well fluids. Each of MWCC’s MCVs are larger than a Naval battleship and have the capability to separate the oil and flare, or burn off, the natural gas. Separated water, oil and sand are stored in the capture vessel and can be offloaded to a shuttle tanker when capacity is reached. Combined, the MCVs have the capacity to capture up to 100,000 barrels of oil and flare up to 200 million standard cubic feet per day (MMSCFD) of gas, which is enough oil to fuel more than three million cars.
The MCVs are equipped with Dynamic Positioning (DP2) capability which allows them to maintain a fixed position without anchors. MCVs can be stationed up to a mile away from the incident site which reduces response traffic directly over the well site and increases the safety of our Response Team by keeping them out of the direct response field.