TORONTO - Superior Plus Corp. (SPB.TO) has signed a deal to buy the Canwest Propane industrial propane business in Western Canada from Gibson Energy Inc. (GEI.TO) for $412 million.

Canwest is a 30-year-old company with more than 50,000 customers, including international, national and large regional companies, making it one of Canada's largest industrial propane distributors.

Toronto-based Superior Plus said it's aiming to find at least $20 million in pre-tax synergies within 24 to 36 months of closing the transaction.

Gibson Energy will continue to operate Canwest -- which also does business under the Stittco brand -- with the current management team until the transaction closes in the second half of this year.

Calgary-based Gibson Energy, which provides a variety of storage, processing, transportation and distribution services for the oil industry, set up a process last year to sell Canwest.

Stewart Hanlon, Gibson Energy's president and chief executive officer, said Monday the deal fully values the Canwest business and will allow the company to reduce debt and focus on its infrastructure business.