Boiler Work Heats Up Savings at DuPont

DuPont Canada Inc, an Industrial Energy Innovator, continues to lead in its efforts to reduce energy costs and consumption. The latest example of DuPont's energy efficiency initiative can be found at its Customer Technical Centre (CTC) in Kingston, Ontario, where recent boiler work is expected to result in annual energy cost savings of $220,000.

The centre, supplied with services from the main site located approximately 300 m (1000 ft.) away, houses a number of textiles labs and some research facilities as well as members of the corporate procurement group, central engineering and DuPont's main engineering contract partner, Fluor Canada Ltd.

Various problems with the steam supply over the past 10 years include numerous leaks from the insulated, 8-inch, 250-psi steam line located underground. Heat loss through 300 m (1000 ft.) of underground piping was substantial as it was discovered that the pipe insulation had mostly deteriorated.

	DuPont could easily trace its steam line in winter, as the ground was never frozen and the grass grew year-round. Steam is used mainly for heating buildings.

In the winter, the ground temperature above the steam line has been measured at 20–25°C where the pipe is 3 metres (10 feet) below grade, and as high as 85–90°C at a point where the pipe enters the CTC building at 1 metre (3 feet) below grade. Steam flow during the summer – when there are no users at the CTC – has been measured at 907–1360 kg (2000–3000 lbs.) per hour. With flow increasing in the cooler months, DuPont has estimated heat losses at up to 7175 kg (7000 lbs.) per hour of 250-psi steam.

Owing to the distance from the plant to the CTC building, DuPont does not recover any condensate from this location, which resulted in a further loss of both heat and treated water. The cost of digging up the line, replacing it and re-insulating it was exorbitant. The solution was to use the steam and condensate savings to pay for the installation of small local boilers (and to recover the condensate) to supply the CTC's needs.

New boilers installed at DuPont's Customer Technical Centre in Kingston, Ontario, are expected to result in annual energy savings of 33 000 GJ per year.

The project, with a cost of $1.2 million, was considered a perfect fit under DuPont's Performance Contract Master agreement. Annual energy savings, steam plus recovered condensate, are estimated at 33 000 GJ per year with an attendant 1780 tonnes reduction of greenhouse gases per year. Constructed in 2002, the project came on-line January 8, 2003. The old steam line was isolated on January 9 at the main plant to start the energy savings.