The Graham Desuperheater can be found in a variety of applications, including:
Power generation
Boilers running at reduced loads, or with high cycling, produce variable temperature steam. Graham Desuperheaters can stabilize superheat over wide flow ranges.
Surface condensers work most efficiently when supplied with saturated steam. This eliminates the need to add tubes for cooling superheated steam, and prevents stresses caused by thermal expansion when hot, dry steam enters the condenser.
Turbine bypass systems require systems of pressure reducers and desuperheaters to reduce the pressure and temperature normally handled by the turbine.
Process controllability
Graham Desuperheaters can help control a variety of processes. If steam temperature is not constant, a process may become uncontrollable, especially when steam flow or pressure fluctuates. This can impact product quality, force unscheduled downtime, create personnel safety issues, and cost a great deal in repairs and replacements.
Thinner pipe and lighter flanges
Cooler steam can require thinner pipe schedules or smaller flange classes than superheated steam. Aside from lower costs, this can reduce lead times for piping, valves, controls, and other equipment during initial construction or shutdown maintenance.
Preventing lubricant degradation
Superheated steam may quickly degrade certain lubricants, so saturated steam is preferred for expensive specialty items such as pumps and compressors.
Protecting downstream equipment
Some metals are not suitable for high temperature service, but desuperheated steam often allows use of carbon steel and lower grade alloys instead of stainless steels and high-grade alloys, which are often necessary at high temperatures.
Properly designed desuperheaters ensure complete atomization of water droplets, and thorough evaporation and mixing downstream. This prevents damage to elbows, valve seats, heat exchanger tubes, other downstream equipment, and even some products
Gas desuperheaters
Desuperheaters are usually designed for steam cooling, but the same principles apply to any vapor. Graham has decades of experience designing and fabricating gas desuperheaters. Recent applications include methanol, toluene, natural gas, R-134a, and air. We can also design for any mixture of gases required.
