Dew Point Heating

General

In most projects, the delivered gas pressure must be reduced to the pressure required by the consumer(s). When the gas pressure decrease, the gas temperature will also cool down (Joule-Thomson-Effect). For this reason, the gas must be heated up before the gas pressure is reduced in order to avoid that a gas temperature can develop a temperature that the aggregate condition of the gas components will change from gaseous to liquid (dew point). The common technology for the pew point heating is the use of indirect water bath heaters or hot water systems that supply heat-exchanger(s) with the necessary heating medium

Indirect water bath heater (IWBH)

An indirect water bath heater is a simple and safe method for heating the gas indirectly. A water bath is heated by a fire tube with burner submerged at the bottom of the heater vessel. The hot water then heats up the process gas in a submerged U-tube bundle or a coil. Water-glycol mixtures are very common solutions for most low-temperature heating applications.

Hot water system with heat-exchanger

This system is based on the same technology as the IWBH. The difference is that the hot water system is located externally (not direct in the gas area) and the heat-exchanger(s) are supplied with the heating medium via pipes.

Sizes and pressure rating

Main design criteria

Design code: ASME, AD2000, CE, NACE-Code MR 0175 / ISO 15156

Water capacity

Pressure loss calculation

Corrosion allowance

Forced draft burner or natural draft

Emission (CO2, NOx, …)

Water quality, corrosion protection

Insulation design (stack connection)

All design criteria, sizes or pressure ratings can be offered on request

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