Liquid jet Vacuum ejector

Liquid jet vacuum ejectors(exhausters)suck off gases and/or vapours from a process. The lowest possible suction pressure in the reactor is only limited by the vapour pressure of the motive liquid. It is possible to compress to atmospheric or even higher pressure. Liquid jet exhausters are manufactured in a variety of materials however these are typically Carbon Steel, Stainless Steel and Bronze, special materials such as Hastelloy are also available. Liquid jet vacuum ejector, when water is used as the motive medium, can be directly coupled to the water line. If, however, the water consumption has to be as economical as possible, the operating water may be circulated. This is also the case when other liquids are used as the motive medium, instead of water. The temperature of the operating liquid may be kept low by the constant addition of a small quantity of fresh liquid. Higher vacuum can be achieved by further cooling of the operating liquid. This is particularly expedient when the suction flow contains condensable components, e.g. solvents. In such a case the vacuum pump can be operated by using the condensate as the motive medium. The lowest suction pressure which can be obtained with a suction capacity of zero (blind vacuum) corresponds to the vapor pressure of the motive liquid which depends on the temperature of the liquid. The action of liquid jet pumps is based on the fact that the liquid jet coming out of the motive nozzle at high speed entrains air, gas, liquid or solid matters from the head of the jet pumps and compresses them to atmospheric pressure.

Avantages

No other pumping-mixing device offers all these outstanding features:

• Safe – Exhausters can be used in hazardous locations where electrically operated alternates would require explosion proofing at considerable cost.
• Low Cost – Units are small in relation to the work they do and cost is correspondingly low.
• Versatile and Reliable – Even under severe service conditions these exhausters will operate reliably. They can be used where other pumping devices would not be practical and are ideal for intermittent service.
• Self Priming – Exhausters are self-priming. They operate equally well in continuous or intermittent service.
• Easy to Install – Connections can be made to suit your piping requirements. Little space is required to accommodate units and they are normally so light in weight they can be supported by the piping to which they are attached.
• No Moving Parts – Exhausters are exceedingly simple and reliable. There are no moving parts to wear or break in a basic exhauster, and require little attention, only periodic inspection and maintenance.
• Corrosion and Erosion Resistant – Because they can be made of practically any workable material, or coated with corrosion-resistant materials, exhausters can be made highly resistant to the actions of the liquids handled or the environment in which located.

Applications

General

Liquid jet vacuum pumps with threaded connections are mainly used in chemical laboratories for the production of vacuum, for example in vacuum distillation or drying. They are also used for evacuating syphon lines, suction lines of circulating pumps and condensers; for deaeration of pressure vessels and for producing negative pressure in Nutsch filters.

Shipbuilding

• evacuation of suction pipelines of non-self-priming centrifugal pumps

Sea-water evaporators

• generation of the necessary vacuum

Dredgers

• de-gassing of the dredged materials (removal of natural gas)

Power plants

• evacuation of turbine condensers

Chemical industry

• evacuation of condensers
• removal of air-/product vapour mixes in vacuum processes