Water Bath Vaporizers

The VFTU series are 'fire tube burner-generated' hot gas heated water bath vaporizers. Hot gas is generated by a burner system and circulated through heat exchangers heating water retained in a ballast tank to the required temperature; cryogen is vaporized through tube bundles by direct contact with hot water.

VFTU series generated hot gas heated water bath vaporizers are generally used for the higher capacity requirements. They range from 250,000 SCFH to in excess of 3,000,000 SCFH (6,600 to 80,000 Nm3/hr). They are most commonly used in pipeline back-up service or other high volume systems such as steel mills, or LNG peak-shaving and LNG send-out station duty.

Tube bundles are available in standard incremental sizes, as are the tanks. Bundles and tanks can be used in a variety of combinations to achieve most customer requirements of steady state capacity and ballast time. Several different process and pressure building bundles can be installed in a single tank. These systems are essentially self contained requiring only on site connection of services and gases prior to being operational.

These direct fired vaporizers are more expensive for a given capacity than a direct steam vaporizer, but hot water bath vaporizers offer several advantages. The biggest advantage is that the water ballast in the tank can store energy and thereby allow process gas vaporization to continue even after loss of the hot gas heating supply. The ballast time is variable and is often specified by the customer, particularly for back-up systems. If no ballast time is specified, 3 to 5 minutes is typical of the design. Ballast times up to 30 minutes have been specified and achieved for some high volume plant back-up systems.

Water heated tank and coil vaporizers. Steam heated hot water is maintained in an insulated stainless steel tank, cryogen is vaporized through a submerged copper or stainless steel coil.

Steam sparged vaporizers and VSI series vaporizer units are designed for relatively modest capacity (50,000  150,000 SCFH or 1,300-4,000 Nm3/hr). ideal for general process use applications, and where non-coded process coils and vessels are acceptable. The process coil is a vertical, helically coiled tube, available in copper or 304SS. They are available with optional pressure building circuits, and are supplied with steam controls and a 500-gallon (2,000 litre) polyurethane insulated ballast tank.

Steam is sparged into the water to maintain the tank temperature, and the condensate must drain to a gravity drain or sump. The VSI series are the lowest cost steam-sparged water bath vaporizers, and are a standard design. Special design requirements for VSI vaporizers are available at additional cost, and relatively minor changes such as designing for low steam pressure can generally be accommodated.    

Manufacturer and supplier of steam sparged (VSSU series) vaporizers, steam sparged water heated shell and tube vaporizers. Steam is sparged into water retained in a ballast tank heating it to the required temperature, cryogen is vaporized through the tubes by direct contact with hot water.

VSSU series steam sparged water bath vaporizers are generally used for the higher capacity requirements. They range from 250,000 SCFH to in excess of 3,000,000 SCFH (6,600 to 80,000 Nm3/hr). They are most commonly used in pipeline back-up service or other high volume systems such as steel mills.

Tube bundles are available in standard incremental sizes, as are the tanks. Bundles and tanks can be used in a variety of combinations to achieve most customer requirements of steady state capacity and ballast time. Several different process and pressure building bundles can be installed in a single tank.

These units are more expensive for a given capacity than a direct steam vaporizer, but steam sparged water bath vaporizers offer several advantages. The biggest advantage is that the water ballast in the tank can store energy and thereby allow process gas vaporization to continue even after loss of the steam supply. The ballast time is variable and is often specified by the customer, particularly for back-up systems. If no ballast time is specified, 3 to 5 minutes is typical of the design. Ballast times up to 30 minutes have been specified and achieved for some high volume plant back-up systems.

The direct fired (VFTU Series) vaporizers offered by us are 'fire tube burner-generated' hot gas heated water bath vaporizers. These are generally used for higher capacity requirements and are commonly used in high volume systems like steel mills, LNG peak-shaving and LNG send-out station duty and pipeline back-up services.

Manufacturer and supplier of water heated shell and tube vaporizers. Hot water from an outside source circulates through the shell, cryogen is vaporized through the tubes.

Water heated vaporizers are similar in appearance to the direct steam vaporizers and fall somewhat between the VSU and VSSU with regard to vaporizing efficiency per unit of surface area. Performance is relative to the available water temperature.

They are extremely simple to operate. The VWU series vaporizer can be used either as part of a water circulating vaporizing system (WCV) or as a stand-alone vaporizer where the customer provides the water, usually as part of an existing cooling water stream. The vaporizer is able to operate in either vertical or horizontal configuration. Capacity is dependent upon shell side water temperatures. Water circulating vaporizers are ideal when the gas outlet temperature is sensitive and must not be elevated going to the process.

The vaporizer is designed such that the flow rate of the available water is matched to the required maximum vaporization heat load. This ensures full vaporization of the incoming cryogen with an acceptable gas outlet temperature. The water flow rate becomes a fixed parameter drastically simplifying the controls necessary to operate the vaporizer. If the cryogen flow diminishes full vaporization is still achieved, but the gas outlet temperature approaches closer to the water temperature, but still within an acceptable value for the process. It cannot be elevated above the temperature of the water. In this mode of operation the vaporizer "self controls" requiring only a minimum of additional simple controls.

Individual heat exchangers are commonly used as a local product vaporizer, and also for disposal vaporizers for air plants. They can be utilized as part of a large WCV system, these units are frequently used in back-up service.