Yokogawa Controllers Supply Steam to USNS Mercy

On the United States Navy Hospital Ship Mercy, Yokogawa's Indicating Controllers are used to control two Foster Wheeler boilers supplying steam to 2 GE turbines to generate 18.3 MW of power.

Classic Controls, Inc.
https://classiccontrols.com

Reduce Standby Cycling to Optimize Boiler Operation

There are savings to be had by controlling boiler standby cycling

Heating of commercial and institutional buildings presents a case where there are energy savings available through the application of an additional controller able to substantially reduce boiler operation time.

Building owners, boiler engineers, operators and other stakeholders will benefit from this simple and understandable video explanation of some of the inefficiencies associated with boiler operation, and how incorporating a better control method can minimize boiler dry firing (also called standby cycling). Boiler operation costs can be reduced between 10% and 25%, with a commensurate reduction in carbon footprint, by including the Fireye NXM2G control in the boiler control system.

Watch the video. It's just a few minutes and explains the source of the inefficiency, as well as the solution, in a manner understandable to everyone. More information is available from a combustion product specialist, who can help evaluate the efficiency of your current system or assist with incorporating the latest energy saving features and design into a new installation.

Steam Desuperheaters

Diagram of one type of steam desuperheater
Schutte & Koerting

Steam has been a preferred means of delivering energy for many decades. Whether used for propulsion, as when driving a turbine, or delivery of heat, steam has proven to be an acceptably reliable and safe means of energy transfer.

Steam can exist in a saturated or superheated state. When saturated, molecules are at the minimum energy level needed to maintain a gaseous state. Superheated steam is essentially steam that has additional sensible heat content beyond what is necessary to create saturated steam. Some processes, such as turbines, will operate best with superheated steam. Heat transfer processes will often provide their best efficiency with saturated steam. Whatever the case, there can be instances where it is preferential, or necessary, to reduce the superheat level of process steam.

Desuperheaters reduce the sensible heat content of steam through a number of methods, most that involve adding finely atomized water to the steam flow. The document included below outlines various construction methods and principles of operation for steam desuperheaters. The illustrations, diagrams, and explanatory content will provide a useful overview of this common industrial process, including application examples.

Types of Steam Desuperheaters from Classic Controls, Inc.