Posted by Mike Pilling on October 25, 2001 at 08:43:37:
Here is a ROUGH rule of thumb for a "ballpark" estimate on cost of steam, which assumes the following:
* natural gas as fuel
* saturated steam
* watertube boilers
* no economizer or air heater
Take cost of gas per mmBTU
Multiply by 1.3
Multiply by boiler efficiency
= cost/1000 lb.
EXAMPLE: Gas $6.00 mmBTU X 1.3 = $7.80
$7.80 X 0.85 efficiency = $9.18 per 1000 lb.
As I said, this is a very rough method and does not include labour, maintenance etc etc, but it comes pretty close in the majority of industrial non-superheated steam plants
Mike Pilling
Chief Engineer
Molson Brewery, Vancouver, BC