Perhaps you’ve had this experience: a recipe calls for two whole eggs and two egg whites. What to do with the extra yolks? Many of Canada’s natural gas and oil producers face a similar challenge, only it’s not about egg yolks, it’s about heat.
Reducing emissions means operating as efficiently as possible, which in turn means capturing a ‘waste’ product and finding another use for it. At oil and natural gas sites, heat is generated from a variety of processes and equipment. Instead of releasing heat into the air, it can be re-directed to another process, avoiding the need to burn additional fuel to create more heat or generate electricity.
Waste heat recovery units (WHRUs) are heat exchangers that capture heat from high-temperature processes. There are literally hundreds of examples of WHRUs in action across the energy industry – like these:
Birchcliff Energy’s Pouce Coupe Gas Plant in northwestern Alberta processes up to 340 million cubic feet of natural gas daily. Four WHRUs at the plant capture heat from compressors, and the heat is then used elsewhere in the plant. The result: total emissions from the plant have been reduced by more than 15,000 tonnes of carbon dioxide (CO2) annually, about the same as emissions from 5,000 cars. The heat recovery program is so successful, Birchcliff is installing another WHRU at Pouce Coupe, expected to cost over $2 million dollars.
NuVista Energy produces natural gas and natural gas liquids, mainly from properties near Grande Prairie in northwestern Alberta. Since 2018, NuVista has invested more than $7 million to install 13 waste heat recovery units on all its compressors, thus avoiding emissions of 32,000 tonnes each year. The captured heat is used for site heating, and the energy saved is equal to taking 9,800 cars off the road every year.