Desuperheating Purpose

Boilers and turbine extraction produce superheated steam hotter than saturation temperature. Many process users require saturated steam for efficient heat transfer. Desuperheater adds controlled water reducing temperature to target conditions matching equipment requirements.

Operating Principle

Superheated steam flows through desuperheater. Atomized water spray injects into steam. Evaporation absorbs superheat cooling steam to saturation. Precise water control achieves target outlet temperature. Excess water creates wet steam damaging equipment.

Desuperheater Design

Pipe section with water injection nozzle creating fine spray, mixing zone ensuring complete evaporation, thermal liner protecting pipe from thermal shock, outlet temperature sensor providing feedback, control valve modulating water flow. Simple inline installation in steam piping.

Water Injection

Spray nozzle atomizes water into fine droplets maximizing surface area for rapid evaporation. Multiple nozzles for large steam flows. Proper atomization prevents unevaporated water carryover. Nozzle design prevents plugging from water impurities.

Temperature Control

Outlet temperature transmitter measures steam condition. Controller modulates water valve maintaining setpoint. Fast response prevents temperature swings. Typical control accuracy ±5-10C. Safety limits prevent overspraying creating wet steam.

Material Selection

Stainless steel or alloy construction withstands thermal cycling. Thermal sleeve protects injection zone from thermal shock. Water injection components resist erosion and corrosion. Design accommodates steam temperatures and pressures.

Operating Pressure

Low-pressure steam systems typically 15-150 psig. Design pressure per ASME B31.1 power piping or B31.3 process piping codes. Pressure rating provides safety margin above operating conditions.

Water Quality

Requires treated water meeting boiler feedwater standards. Dissolved solids, hardness, and contaminants cause scaling and deposits. Demineralized or condensate-quality water prevents problems. Poor water quality fouls nozzles and damages equipment.

Applications

Process steam users requiring saturated conditions, sterilization equipment, jacketed vessels, heat exchangers, humidification systems, and any low-pressure steam application where temperature control critical.

Installation

Positioned upstream of steam users requiring temperature control. Adequate straight pipe downstream ensures complete mixing. Drain connection below desuperheater removes any condensate. Insulation maintains temperature after desuperheating.

Performance Benefits

Protects equipment from excessive steam temperature. Optimizes heat transfer through proper steam quality. Prevents thermal shock to process equipment. Simple proven temperature control technology.

Construction Standards

Design per ASME B31.1 or B31.3 piping codes. Water injection system per manufacturer standards. Materials for steam and water service. Complete documentation with thermal calculations.

ERGIL LP steam desuperheaters provide reliable temperature control delivering properly conditioned low-pressure steam for process applications.