Steam Power And Co-Generation

The objective of this fifth module is to focus attention on the areas of control which are essential for successful boiler operation including; automatic controls, boiler water conditioning, and environmental control.

On completion of this module the participant should understand the following concepts and apply them in day-to-day activities.

• The basic control loop
• Control signals; analog and digital
• Typical control system logic:

1. Combustion control
2. ID Fan Control
3. Steam temperature control
4. Drum level control

• Auto-manual change over
• The need for boiler water conditioning
• Scale deposits and their causes
• Continuous blowdown
• Phosphate addition
• Causes of carryover
• Effects of silica in boiler water
• Causes of internal corrosion
• pH control; caustic addition
• Congruent phosphate control
• Removal of O2 and CO2 from feedwater
• Oxygen scavenging; hydrazine
• Source of boiler pollutants
• Environmental effects of pollutants
• Pollution control equipment to reduce emissions of particulates, SOx, NOx
• Treatment of liquid effluents and solid waste.