© ABB Inc.May 31, 2011 | Slide 1

WMP-113-1 Feedwater heater control:Bring your efficiency to a new LEVEL

ABB Automation & Power World: April 18-21, 2011

© ABB Inc. May 31, 2011 | Slide 2

WMP-113-1 Feedwater heater control: Bring your efficiency to a new LEVEL

Speaker name: Kevin Hambrice

Speaker title: Global Factory Sales & Marketing Manger - LEVEL

Company name: K-TEK, A Member of the ABB Group

Location: Prairieville, LA

© ABB Inc. May 31, 2011 | Slide 3

Feedwater Heater ControlWhy is feedwater heater level control important?

Heaters preheat feedwater before boilers converted it to steam

“Preheating” reduces energy to flash the water into steam

Liquid level of condensate is formed as steam condenses

Level is controlled to create a seal and prevent steam blow-through

Accurate and repeatable level measurement keep boiler fuel consumption down

© ABB Inc. May 31, 2011 | Slide 4

Feedwater Heater ControlWhat are you controlling and why?

Injected steam condenses and acts as a seal to prevent blow-through of steam in the heater

Maximum thermal transfer between steam & feedwater takes place when largest tube area exposed to steam

Small increase in condensate level (2-in to 4-in) over minimum greatly reduces the heat rate efficiency)

Feedwater Heater ControlTraditional Devices Used for Feedwater Level Measurement

Mechanical displacement type level systems with pneumatic controllers have been used

Two major issues

1. Mechanical nature requires high maintenance due to seal and bearing failures and air supply issues

2. Varying liquid density of water and steam creates significant measurement errors in displacer.

© ABB Inc. May 31, 2011 | Slide 5

Sight Glass

Displacer

Differential Pressure

Conductivity Probes

Feedwater Heater ControlBest Practice Feedwater Level Control

Magnetic level gauges and magnetostrictive level transmitter used to improve control

Performance and reliability control condensate level at 2” to 3” above the drain

More tube area is exposed to heat and additional feedwater with the same energy input

Increases heater throughput and efficiency

Accuracy (±1”) of the system prevent steam blow-through

© ABB Inc. May 31, 2011 | Slide 6

Certified to ANSI/ASME

B31.1

360º Magnetic Ring75 Grams Buoyancy

Feedwater Heater ControlPrecision Measurement for Changing Process Conditions

Thermocouple can be installed to compensate for density changes of the condensate

Small small change float buoyancy affects accuracy

Simples correction in DCS, allows lower condensate levels in the heater

Improves efficiency even more

© ABB Inc. May 31, 2011 | Slide 7

Feedwater Heater ControlProven Success

“We saw a return on investment and efficiency gain within 6 months”

“I’ve been pleased with the significant maintenance savings with the elimination of sight glass repairs.”

“We were looking for a reliable solution that would be accurate and repeatable – we got this with the MLT technology.”

© ABB Inc. May 31, 2011 | Slide 8

© ABB Group

May 31, 2011 | Slide 9

Improving Power Plant Efficiency ABB – Your partner for Measurement Solutions

World class instrumentation solutions built on over 100 years of experience

Built upon the leading names and brands in the automation world:

Unrivalled in its scope and applications expertise

Solutions certified to international standards

Worldwide network of sales offices and manufacturing plants

© ABB Group May 31, 2011 | Slide 10