A pig launch and recovery apparatus independently mountable to and removable from a water supply system including at least one water main and valve. The pig launch and recovery apparatus comprises a flow tube and a launch and recovery tube. The flow tube includes first and second flow ends and a main flow valve located between the first and second flow ends. The first flow end is removably mounted to a recirculating unit including a pump. The second flow end is removably mounted to a first point in the system. A launch and recovery tube further includes first and second launch ends, wherein the first launch end is fluidly connected to the flow tube between the first flow end and the main flow valve, and wherein the second launch end is fluidly connected to the flow tube between the main flow valve and the second flow end.

Systems and methods for efficient on-line pigging of a coker furnace without interruption of the delayed coking process, which will save time and money during the delayed coking process. This system can be retrofitted to existing coker furnaces.

Systems and methods for efficient on-line pigging of a coker furnace without interruption of the delayed coking process, which will save time and money during the delayed coking process. This system can be retrofitted to existing coker furnaces.

An electronic computing system preserves a pre-error state of a processing unit by receiving a first stream of inputs; buffering the first stream of inputs to generate a buffered stream of inputs identical to the first stream of inputs; conveying the first stream to a primary instance of a first program; conveying the buffered stream to a secondary instance of the first program; executing the primary instance on the first stream in real time; executing the secondary instance on the buffered stream with a predefined time delay with respect to execution of the primary instance on the first stream; detecting an error state resulting from execution of the primary instance; and in response to detecting the error state, pausing the secondary instance and preserving a current state of the secondary instance, wherein the current state of the secondary instance corresponds to a pre-error state of the primary instance.

An electronic computing system preserves a pre-error state of a processing unit by receiving a first stream of inputs; buffering the first stream of inputs to generate a buffered stream of inputs identical to the first stream of inputs; conveying the first stream to a primary instance of a first program; conveying the buffered stream to a secondary instance of the first program; executing the primary instance on the first stream in real time; executing the secondary instance on the buffered stream with a predefined time delay with respect to execution of the primary instance on the first stream; detecting an error state resulting from execution of the primary instance; and in response to detecting the error state, pausing the secondary instance and preserving a current state of the secondary instance, wherein the current state of the secondary instance corresponds to a pre-error state of the primary instance.

A pig diverter comprises a hollow housing having a flowline inlet port, a flowline outlet port, a pig entry opening, and a pig exit opening, all communicating with the interior of the housing. A tubular pig holder enclosed by the housing is pivotable between a receiving position and a launching position. In the receiving position, the pig holder is aligned with the pig entry opening to receive a pig and effects fluid communication between the pig entry opening and the flowline outlet port. In the launching position, the pig holder is aligned with the pig exit opening to launch a pig and effects fluid communication between the flowline inlet port and the pig exit opening.

A pig diverter comprises a hollow housing having a flowline inlet port, a flowline outlet port, a pig entry opening, and a pig exit opening, all communicating with the interior of the housing. A tubular pig holder enclosed by the housing is pivotable between a receiving position and a launching position. In the receiving position, the pig holder is aligned with the pig entry opening to receive a pig and effects fluid communication between the pig entry opening and the flowline outlet port. In the launching position, the pig holder is aligned with the pig exit opening to launch a pig and effects fluid communication between the flowline inlet port and the pig exit opening.

A pressure vessel defines an opening with a shoulder around a periphery of the opening. A door is configured to regulate access to the opening. The door is configured to compress against the shoulder when in the closed position. A first seal is between the door and the shoulder. The first seal touches an interior side of the door and the shoulder when the door is in the closed position. The first seal is configured to seal fluid within the pressure vessel. A second, active seal surrounds a periphery of the opening. The seal is actuable between an engaged position and a disengaged position regardless of a position of the door. The second, active seal touches the periphery of the door, perpendicular to the first seal, when in the engaged position and the door is in the closed position. The second, active seal is configured to seal fluid within the pressure vessel.

A pressure vessel defines an opening with a shoulder around a periphery of the opening. A door is configured to regulate access to the opening. The door is configured to compress against the shoulder when in the closed position. A first seal is between the door and the shoulder. The first seal touches an interior side of the door and the shoulder when the door is in the closed position. The first seal is configured to seal fluid within the pressure vessel. A second, active seal surrounds a periphery of the opening. The seal is actuable between an engaged position and a disengaged position regardless of a position of the door. The second, active seal touches the periphery of the door, perpendicular to the first seal, when in the engaged position and the door is in the closed position. The second, active seal is configured to seal fluid within the pressure vessel.

A method for reducing emissions from a vessel includes isolating the vessel from a downstream fluid flow line, purging a fluid from the vessel by injecting purging media into the vessel to push the fluid through a check valve of a vent tubing and into the downstream fluid flow line, and draining the purging media from the vessel. A first end of the vent tubing is coupled to the housing of the vessel, and a second end of the vent tubing is coupled to the downstream fluid flow line. Further, the vent tubing includes a check valve disposed between the first end and the second end, and the check valve is configured to allow fluid to flow from the housing to the downstream fluid flow line.