Simple system garners big savings
June 1, 2013 by Luc Boily
Knowing that drinking water is not a boundless resource, a group of plumbing and heating teachers involved in the eastern Montreal vocational training school Centre Daniel-Johnson* developed a water-conserving system for the workstations.
Daniel Savard, a plumbing and heating instructor at the Centre, explains the green initiative that he and his colleagues put forward last year within the “Water Heater Troubleshooting” and “Pumping Systems” modules. “We have 21 workstations, and each one has its own water-heater. The latter are purged out and filled up five times a year with the arrival of each new group [of students]; if it was only for the sake of the water savings during those times, it was worth the effort to find a conservation solution,” said Savard.
In addition, to recovering the drain water from the water-heaters, the system has been designed to reuse the water pumped out from various pipe fittings put together by students during learning exercises. Once filtered, the water is going back to the water heaters and pump systems. “We figured out that this system allows us to save about 40 000 litres of water per year,” said Mathieu Laforge, a teacher in the plumbing and heating department.
Drain water is pumped into an underground tank. The photo above shows the location of the tank as well as the pumping system, including a centrifugal pump and a hydropneumatic tank that supplies the water for the water-heaters located in the workstations (see image on right). The system is a closed-loop to prevent the collected water from entering the potable water system. Chlorine is also added to the water.
The gray PVC pipe along the wall (see photo above), which contains about 1150 litres of water, is running around the mechanical room and workstation area. Its purpose is to provide a water source for pumps. It also acts as a water backup to supply water heaters. “The water contained in the PVC pipe, however, was not enough to supply the system needs. So we installed an additional 1500 litre tank,” explained Laforge. Doing so, the system is now able to drain and refill the water-heaters as well as supply pumps without using the water from the aqueduct whatsoever.
ONE STEP AT A TIME
“We believe that the change in consumption patterns happens one green step at a time. We wanted to walk in this direction, also keeping in mind our educational mandate to promote new sustainable deeds,” said Savard.
The Centre Daniel-Johnson Plumbing & Heating module’s initiative is the first phase of a larger project plan. The second phase will aim to broaden the experiment to the hot and cold water distribution system, sanitary equipment and accessories installation module. “The exact phase two beginning date is not yet known, but we expect it to be after some refurbishment work planned by the school board is completed this summer,” said Laforge.
*The vocational training Centre Daniel-Johnson provides 12 educational programs giving access to job opportunities for future professionals in high demand trades.