City of Carlsbad, California, USA
	Waste water facility uses corrosion resistant PSP® for odor control
			Unassuming Lift Station building belies powerful pumps, state-of-the-art odor control units and PSP® duct.
	Carlsbad, California is a beautiful oceanside city located just north of San Diego.  Because of location, climate, low population density, and excellent public schools, the city enjoys a desirable quality of life and has recently attracted many new residents.
	The city government understood that with population growth, demands on the municipal infrastructure would increase. In 2003, the city commissioned a Master Sewer Plan. This plan called for an increase of 45% in waste water treatment capacity by the year 2020.
	Background
	The topography of Carlsbad is hilly, and the elevation of the sewage service area ranges from 600 feet to sea level. A number of pump stations are needed to convey waste water over the hills to the Encina Water Pollution Control Facility ( WPCF ), located on the Pacific Ocean shoreline. The Master Plan indicated an immediate need for a new pump or "Lift" station and over a mile of 14 inch force main piping to be located along Cannon Road. Since the new pump station was to be located in a residential area, it was critical the site be as innocuous as possible and that no odors whatsoever be discerned.
	Odor control has become the most pressing issue in the waste water processing industry. Virtually every part of the collection system from pump/lift stations to force mains and drop structures can produce and release objectionable odors. Airborne hydrogen sulfide is the most prevalent odorous compound from waste water along with other organic chemicals such as methyl mercaptan and dimethyl disulfide. As well as being odorous, the offending vapors are also corrosive, some caustic and others acidic.
	Unique Exhaust Solution
	The city contracted the firm of DHK (Donald H. King) Engineers, Inc. of Escondido, California, to conduct an odor study and make recommendations for equipment / scrubber system. As a solution to the lift station odor control challenge, Mr. King recommended the use of Calgon Carbon "Phoenix" units that use granular activated carbons, specifically designed for waste water odor control.
			Intricate maze of PSP® fluoropolymer coated stain-less steel duct tightly bolted together keeps odorinside the system.
	Camp Dresser & McKee Inc. (CDM) of Carlsbad was hired for overall engineering responsibility. DHK and CDM worked closely with the city and with the electrical, mechanical and facilities engineering firm of Moraes/Pham & Associates, also located in Carlsbad.  Co-owner and principal mechanical engineer, Long Pham, approached the project backed by twenty five years experience in facilities engineering and clean room design. He specified a revolutionary product to manage the transfer of corrosive exhaust vapors for the lift station - fluoropolymer coated stainless steel duct.
			Mechanical Contractor Les Shrum (left) discusses intricacies of PSP® duct installation with Dale Shrum (right), TC Construction Project Manager.
	The evolution of coated duct began in the semiconductor industry of the early 1990's. Fire damage to manufacturing facilities spread via exhaust systems made of combustible materials resulted in a string of catastrophic losses. To address the challenge for corrosion resistant exhaust systems impervious to fire, Fab-Tech Inc. of Colchester, Vermont developed a process to integrally bond a fluoropolymer to the inside surfaces of 300 series stainless steel duct. Fab-Tech's PermaShield Pipe (PSP®) product delivers: unparalleled corrosion protection, structural integrity and ease of installation.
	Fab-Tech's PSP® duct is in compliance with NFPA 820 and is classified as a true "Class 1" product. This classification has been established by the Uniform Building Code, and is universally accepted by federal, state and local authorities. No fiberglass (FRP) duct system is able to provide the unique combination of exceptional fire and smoke indices, superior corrosion resistance and ease of installation of PSP®.
	Another critical benefit of PSP® is its FM rating.  Factory Mutual (FM) is an affiliate of FM Global, the world's largest insurance company and certifies industrial products that are designed to reduce commercial and industrial property losses. PSP® has earned the FM Approval mark as stipulated in Factory Mutual Research Standard No. 4922.
	Cost Saving Installation
	Over 230 pieces of 16 inch diameter coated stainless steel duct were supplied on the Cannon Road Lift Station project. This complex exhaust system design was expertly installed by Les Shrum, of L.R. Shrum Heating & A/C of Santee, California.  The PSP® coated duct arrived on site exactly when promised and fabricated exactly as ordered. "The system went together marvelously," commented Mr. Shrum. "Everything was fabricated exactly to my measurements ... there was no need for cutting ... all of the fittings and duct pieces were very accurate and exact." The flanged duct connections, assembled with W.L. Gore PTFE gasket material, were bolted and torqued to recommended levels for leak (and odor) free operation.
	PSP® duct is a competitively priced premier product when compared to low-tech fiberglass reinforced plastic (FRP) duct systems. Considerable installation cost savings were realized using PSP® (does not require welding, grinding, sanding or chemicals for assembly) reducing the cost of installation labor by more than half opposed to an FRP system.
	Conclusion
	After nearly a year of operation, the lift station and its odor-control component are working perfectly."  There are no discernable odors even when standing right next to the building," commented Fab-Tech's Vince Rocca, who inspected the facility with colleague David Stearns, Fab-Tech's Wastewater Segment Manager. The Calgon Carbon systems and attached PSP® duct remove up to 50 ppm of hydrogen sulfide at over 99% efficiency. Fab-Tech Inc. is proud to play a part in the innovative solutions that contribute to the quality of life for all those who live, work and play in Carlsbad.