Reliable compressed air drying
October 20th 2011

HI-LINE has re-engineered its proven membrane dryer. The outcome is a technologically superior product - the Hi-DRI - which will set new standards in membrane drying with regard to energy efficiency, says the firm.

Besides filtration, compressed air drying contributes considerably to an increase in the process reliability. Humidity in compressed air systems causes corrosion and promotes the growth of micro-organisms. In individual cases, condensate may even emerge at the compressed air´s point of use.

Pneumatic controls break down where humidity is introduced, wear and tear of tools is enhanced or disturbances occur in the production process. Thus, the industrial process is consistently at risk where users employ compressed air.

The company says: "Therefore, efficient drying of compressed air is of essential importance. This applies in particular for the drying directly at the compressed air consumer. Drying orientates not only on the application itself but also on the ambient conditions, e.g. on ships, in open manufacturing shops or outdoors. For all these cases, HI-LINE will present the new generation of membrane dryers Hi- DRI at the beginning of November 2011 as a superior solution, by means of which almost any degree of drying may be achieved."

Hi-DRI will be available in several sizes for varying degrees of drying, from 17 to 1050 l/min. By selecting the appropriate dimensioning from the wide range of products, almost any dewpoint may be achieved. Higher volume flows can be achieved through a parallel connection of several modules.

Spiral Wound Membrane

Hi-lines’ Hi-DRI Membrane Dryers use a patented, structurally packed arrangement of the hollow fibres. Fibres repeatedly placed and wound around a centre core create an optimised, compact design that allows for efficient use of air flow and the available contact area to maximise drying performance and reduce the required footprint.

• Creates optimised and compact design

• Maximises the drying performance

How the Proprietary Membrane Technology Works

1. Hollow fibres allow water vapour to pass through the membrane while retaining the compressed air.

2. As the humid compressed air flows down the bore of the fibre, water vapour diffuses through the walls of the fibres.

3. At the unit’s outlet, a small volume of the dry compressed air is expanded and released into the space surrounding the outside of the fibres.

4. This dry air sweeps the moisture away from the outside of the fibres and exhausts to the atmosphere as a humid air stream.

5. As a result, the membrane rapidly and continuously provides dry compressed air.

A Proven Technology That Increases Equipment Reliability

HI-DRI air dryer technology is proven to make it easier and less expensive to provide pneumatic equipment and instrumentation with clean, dry compressed air. This reliable drying technology helps ensure that no

condensation, oxidation and microbiological growth occur in your compressed air equipment. Reliable and predictable performance of pneumatic equipment and instrumentation saves money by reducing component

failures, warranty costs and improving equipment performance and operator satisfaction.

Compact, Lightweight, Cost Effective

Compact and lightweight, Hi-DRI Membrane Air Dryers easily integrate into existing compressed air systems and are virtually invisible to your process. Hi-DRI is cost effective and simple to operate.

Easy to Install

Hi-DRI Membrane Air Dryers are designed with ease-of-installation and operation in mind. Simply connect the inlet and outlet. No adjustments. No valves. No drain. No electrical connections.

Maintenance-Free Design With No Moving Parts

Hi-DRI Membrane Air Dryers are maintenance-free, reliable, and provide the lowest overall operating costs. Polymeric hollow fibre membrane requires no maintenance, and there are no moving parts to wear out and no refrigerants or desiccants to replace.

Simple Membrane Protection Ensures Optimal Life and Performance

Hi-DRI will perform reliably with appropriate pre-filtration—we recommend a minimum of 0.01μ coalescing filter element to prevent particulates, oil aerosols and liquid water from entering into the module. A regular change-out of the coalescing filter element is all that’s required to ensure years of continuous operation. Utilising Hi-line HF series of filters will lead to optimum lifespan

Ideal for Plant, Commercial or Lab Applications

The Hi-DRI Membrane Air Dryers are suitable for a wide variety of industrial plant applications as well as for commercial and laboratory applications. Models are available in a variety of flow rates up to 3 cubic meters per minute. Multiple units can also be connected in parallel to achieve higher flow rates. For most dew point ratings, flowrates and operating pressures there’s a Hi-DRI Membrane Air Dryer that’s ideal for your application.

Adjustable for any Dew Point Requirement

The required outlet dew points of the Hi-DRI Membrane Air Dryer can be set for any desired operating conditions.

Typical outlet dew points

• +0˚C to 6˚C: This is the typical dew point achieved by refrigerated air dryers. This dew point is specified in most industrial applications.

• -20˚C: This dew point is often used in medical and process plant applications.

• -40˚C: This dew point is specified for high quality instrument air.

Staged drying by means of central refrigeration drying is particularly cost-effective, e.g. with the CDA refrigeration dryer connected directly to the compressor, followed by decentral membrane drying using Hi-DRI in the small output range, subsequently followed by the compressed air consumer. HI-LINE thus offers the optimum solution for any application as far as compressed air drying is concerned.

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