Desuperheaters Overview

Desuperheating, sometimes called attemperation or steam conditioning, is the reduction of gas temperature. Its most common application is the reduction of temperature in a steam line through the direct contact and evaporation of water. Most Desuperheaters incorporate the venturi design which uses the velocity of the steam to atomize the cooling water. In addition, Ejector Atomizing Desuperheaters, Attemperator Desuperheaters, Surface Absorption Desuperheaters, and Mechanical Atomizing Desuperheater designs are available. In most types, water pressure requirements are the same as the steam line pressure.

Desuperheater Types

Venturi Desuperheater

(reduces steam temperature by bringing superheated steam into direct contact with water and normally used in areas where atomizing steam is not available)

Annular Venturi Desuperheater

(capable of high turndown ratios and suitable under wide range of conditions, including steady and variable flows)

Annular Venturi Orifice Desuperheater

(eliminate the accumulation of unvaporized water in the pipeline; offering increased turndown capacity in comparison to other desuperheaters)

Attemperator Desuperheater

(used for relatively steady load conditions where pressure losses must be minimized; offering increased turndown when mounted vertically up)

Steam Ejector Atomizing Desuperheater

(for applications where combined reducing desuperheating station is required and flows vary widely)

Mechanical Atomizing Dump Desuperheater

(developed for economically desuperheating high steam flows in large steam line)

Surface Absorption Desuperheater

(desuperheat steam by forcing it to come in contact with wetted metal reaction rings – generally used where space limitations are a factor and requirements of minimum water carryover exist)


General Applications:

Improve heat transfer of surface type heat exchangers; Reduction and control of superheated steam; Use on boilers between superheater stages or at boiler exit; Control superheat temperatures at partial loads; Bypass of bleeder or backpressure turbines to maintain balance between process steam and power requirements; Balancing and make up steam in reducing pressure systems; Desuperheaters; Shipboard service; Industrial heating system; Food processing; Turbine bypass steam temperature contol; Control steam temperature to dryer drums in paper manufacturing; Reduce temperature of high pressure steam reduced to a usable pressure; Control temperature to evaporators; Used in shipboard service; Control steam temperature to dryers in paper industry; Heating system steam conditioning; Process steam temperature control.