| In the Pulp and Paper industry, a significant amount of fresh water is required for both power and processing. Often, the water used in these processes isn’t recycled, necessitating the continuous intake of fresh water, typically at temperatures between 60-65°F.
For power generation, make-up water is added to the boiler system’s deaerator (DA), where steam is injected to heat the water nearly to boiling. This process helps remove oxygen and non-condensable gases.
Various processes also require hot water, such as stock preparation, head box showers, press section showers, wire showers, felt showers, pocket vent heaters, seal water systems, and general mill operations. These hot water streams are usually heated using steam-to-liquid heat exchangers, which rely on boiler steam and incur fuel costs.
At this Midwest papermill, the Condex system utilizes hot exhaust from the boilers to heat process streams and make-up water. This approach reduces the need for steam in heat exchangers and the DA, providing year-round heat sinks whenever the mill is operational. Fuel savings are calculated based on the boiler’s runtime, which is nearly 8,760 hours per year. |
