Optimizing Energy Saving Opportunities in Food and Dairy Plant Steam Boiler Systems

摘要

Food and dairy plants typically employ nominal 100-135 psig steam generated by firetube boilers. A significant number of options in equipment are available to assist in optimizing energy consumption. In addition to properly matching boiler size to anticipated steam demand and maximizing the return of steam condensate, some or all of the following opportunities are applicable to both renovated and new boiler plants: (1) Operation at the lowest possible steam pressure (2) Boiler selection with high turndown burners (3) Economizers: a. Stack-sensible heat only b. Stack-condensing c. Direct contact-condensing d. Indirect contact-condensing (4) Continuous surface blowdown heat exchangers (5) Reverse osmosis (RO) treatment of boiler make-up water to reduce blowdown and chemical consumption (6) Oxygen (O_2) trim control Most of the above opportunities can be considered as "common sense," but many owners are reluctant to increase the steam system first costs by including any or some of the possibilities listed. It is the design engineer's responsibility to provide cost analysis and payback(s) to justify added first cost for energy saving opportunities.