Producing about 13 million litres of alcohol annually requires a lot of energy. It also entails a very complex process and calls for a wide range of operational equipment. That is why the Schenley distillery, whose energy costs amount to approximately $5.5 million per year, decided to use process integration as a means to identify energy-saving measures.
Process integration goes well beyond traditional energy audits by taking a systematic look at all the ways in which energy is used throughout a facility and how its various systems interact with one another.This structured approach enabled the Schenley distillery to have an overall view and thorough understanding of its system operations, allowing its staff to know precisely which aspects needed to be improved in order to save energy.
This process integration study, the first to have ever been conducted at a Canadian distillery, was completed in August 2004. It allowed identifying 11 energy-saving measures, of which 6 had payback periods of less than 1 year. The implementation of all projects could allow Schenley to:
- Gain energy savings of 40%
- Reduce its greenhouse gas emissions by 12,000 tonnes/year
Of the energy efficiency measures proposed, 2 were very quickly implemented by the plant:
- At the thermal power plant (which accounts for about 90% of the distillery’s natural gas costs), improvements were made in terms of preheating the boiler feed water used to generate steam. This was done by adding a new heat exchanger and modifying the fuel system, a measure which generated $84,000/year in savings, with a 9-month payback period
- At the process level, a project was implemented to reuse part of the distillation by-product in the cooking process that produces alcohol, a measure which generated $98,000/year in savings, with a 5-month payback period
Among the other energy-saving measures identified was a mechanical vapour recompression project that would reduce the consumption of live steam used in the evaporators by about 85%. This measure would generate $750,000 in annual savings.
The study was conducted jointly by CanmetENERGY and G.C.I. energy experts. Financial assistance for the process integration study was provided by Natural Resources Canada’s Office of Energy Efficiency (OEE).
To learn more about this project or for additional information about process integration and Pinch analysis, see the:
CanmetENERGY experts also conducted process integration studies in other Canadian food and drink plants. For more information, see the list of success stories for that industrial sector.