The project consisted of relocating an existing Phosgene scrubbing system from one location to another within the United States. The primary scrubbing system consisted of a carbon steel scrubber 3 feet in diameter by 27 feet tall and had a 20 feet packed section with 2” Pall rings. It was capable of handling 2000 pounds per hour of Phosgene as long as the caustic strength was 12% or above. The caustic storage tank was 3000 gallons. A single circulation pump and tower water circulation cooler complete the primary system. The secondary scrubbing system included a 5 feet diameter scrubber by 44 feet tall and had two 16 feet packed sections with 2” cascade mini-rings. The caustic tank for the secondary system was 12,800 gallons. Redundant circulation pumps, single tower water circulation cooler, and redundant blowers complete the secondary system. Two scales for Phosgene cylinders were installed within a new enclosure building. The enclosure building also housed a Phosgene vaporizer. The enclosure was sealed utilizing a “cocoon” sealing system. A new containment area was required as well as new piperacks between the enclosure building and scrubber area.
Piping for this project included tower water supply and return, make up caustic and water to the scrubber caustic tanks, caustic circulation, disposal of spent caustic and collection of phosgene vapors, potable water to safety showers, compressed air, flushing water to pump seals, and analytical tubing. Phosgene vapors were collected from the enclosure and piped to the secondary scrubbing system. The primary scrubber discharge was piped to the secondary scrubber.
A new concrete equipment and tank containment area was provided. Within the containment area, new concrete foundations were provided to support the scrubbers. Waterstops were utilized to integrate the isolated foundations with the surrounding containment area. The new enclosure building consisted of steel columns and beams with metal deck and siding. An air tight cocoon system was utilized throughout the building. The building was to be field constructed prior to being crane lifted and installed into its final place.
Instrumentation and controls design included the specification of new field devices. Instrument wiring was included back to an existing PLC which required new I/O cards. The electrical scope included equipment grounding, structure grounding, power wiring, control wiring, lighting, and heat trace. Electrical power was provided from distribution equipment located within an existing MCC building.