The University of Miami Central Energy Plant represents one of the largest facilities of its kind in South Florida.
Among its features: three high-efficiency, variable-flow 3900-ton chillers piped in parallel and each discharging into a 36-in chilled water piping/distribution system; three cooling towers; three variable-flow 500-hp chilled-water pumps; three constant-flow, 600-hp condenser water pumps piped in parallel; 36-in chilled water piping distribution system; three air separators in the return chilled water piping systems; one chilled water piping bypass; 42-in condenser water piping distribution system; seven chilled-water air-handling units; and a 12,000-gallon fuel oil system, among others.
The ground-floor chiller plant’s network of chilled water and condenser water piping is 15 ft above ground on a steel supporting structure. The location and layout of the chiller plant, inside the new 10-story parking garage, resulted in a unique sequencing effort.
John J. Kirlin, Moss & Associates, the project’s design engineers and structural trades decided to reverse the traditional building order and first construct the plant’s piping and support structure. The precast parking garage was then built around it.
This re-sequencing required coordination with the precast installer to prevent conflicts between pipe installations and both the location of precast tilt walls and the space needed to install them. This change saved almost two months of construction time and helped to maintain the project’s overall budget.
One safety challenge was a result of the sheer size of the 42-in pipe being installed. John J. Kirlin developed and implemented procedures that permitted welders to safely enter a 42-in pipe from 100 ft inside a previously installed pipe located 12 ft above the floor on the ceiling area of the mechanical room.
Due to the limited and restricted means of entry and egress in the pipe, which posed a possible situation of entrapment or asphyxiation, the internal atmosphere in the pipe was tested for the presence of gases, vapors or toxic air contaminates prior to entry. Air from exhaust fans was blown into the pipe at several openings establishing forced-air ventilation to eliminate potential hazards.
A gas monitor was also installed to check air quality while the welder occupied the pipe. The entrant was fitted with a body harness and a retrieval system was established for immediate recovery and rescue with an attendant in continual radio contact.
Water quality is usually maintained in condenser water systems with the use of chemicals. Because this water must be discharged into the sanitary systems for treatment and recycling, impact fees result. To avoid these, John J. Kirlin used a chemical-free system which only discharges the water into drainage wells, eliminating these fees and recurring costs for chemicals, and resulting in a more environmentally-friendly system.
Owner: The University of Miami, Coral Gables, Fla.
Location: Miami, Fla.
Cost: $7.5 million (Specialty)
General Contractor: Moss & Associates, Fort Lauderdale, Fla.
Specialty Contractor: John J. Kirlin, Miami
Design Firm: Newcomb & Boyd, Atlanta