Discover the different adiabatic humidification techniques

In adiabatic humidification, cold water is atomised into an air stream. The water evaporates and extracts heat from the air. The air temperature drops and the humidity rises. Because the air cools during the humidification process, it may be necessary to reheat the air after humidification to reach the desired temperature. No external heat is used during the humidification process itself; the necessary heat is extracted from the air. Adiabatic humidification is therefore known as an energy-efficient humidification method.

Iris van Knippenberg

Marketeer

There are several types of adiabatic humidifiers that operate according to this principle:

We explain these humidification methods in more detail in this blog post.

High-pressure humidification

High-pressure humidification is increasingly being implemented as a sustainable and energy-efficient alternative to steam humidification. Compared to steam humidification, the evaporation process requires significantly less energy.

In high-pressure humidification, water is atomised into very fine droplets under a pressure of 80 to 100 bar. The tiny water droplets are absorbed by the air and evaporate quickly. This allows the humidity in a room to be precisely controlled.

High-pressure humidification is ideal for higher humidification capacities. We recommend this technique for capacities of approximately 20 litres per hour or more. This humidification method can be used in an air handling unit or directly in the room. Does your site have multiple air handling units? If so, a single central high-pressure system can be used to supply humidification to various air handling units.

Advantages:

Energy-efficient & sustainable
Suitable for any air handling unit
Precise control
Humidifies large air handling units using a single high-pressure pump
Low maintenance
Autonomous control or control via the building management system
VDI 6022 approved / ISSO 55.3 certified

Air-assisted humidification

Air-assisted humidification uses compressed air form a compressor to atomise water. This creates very fine droplets that evaporate quickly. This humidification method is ideal for small and medium-sized systems with a capacity of 30 to 40 litres per hour.

The atomisers are installed directly within the room. This means that an air handling unit is not required. During the evaporation process, heat is extracted from the air, causing it to cool. This makes air-assisted humidification highly suitable for rooms with a high internal heat load.

Advantages:

Fine atomisation
Easily scalable
Low capital outlay
Energy-efficient
Low maintenance
Self-cleaning

Ultrasonic humidification

Ultrasonic humidifiers create a fine mist using high-frequency vibrations. The water tank contains vibrating plates that vibrate at a frequency of approximately 1.7 MHz. This produces both large and small water droplets. An integrated fan then disperses this mist throughout the room. As the droplets are very small, the moisture can be quickly absorbed by the air.

Thanks to the fine mist, ultrasonic humidification is ideal for direct use within a room. The mist can also be blown into a duct or air handling unit.

Another advantage is the precise control of humidity. This makes ultrasonic humidification particularly suitable for environments where stable humidity is important, such as museums and cleanrooms.

Advantages:

Energy-efficient
Short absorption path
Precise control
No air handling unit required
Low maintenance
Low noise

Low-pressure humidification

Low-pressure humidification is a compact solution for air handling units where there is limited space available for the evaporation process. The low-pressure humidifier atomises water at a pressure of approximately 10 to 14 bar in the wet section of the air handling unit. The mist is so fine that it is quickly absorbed by the air. Any water droplets that do not evaporate immediately are absorbed by a chemical-free post-evaporation unit.

Low-pressure humidification offers precise control and has low water and energy consumption. As the Cumulus low-pressure humidifier does not use any chemicals, it is suitable for applications with high hygiene requirements, such as in hospitals.

Advantages:

Suitable for use in any air handling unit
Short absorption path
Energy-efficient & sustainable
Easily adjustable capacity
Low maintenance
Chemical-free

Evaporative humidification

Evaporative humidifiers are suitable for air handling units where there is limited space available for the humidification section. Thanks to the range of sizes available, the capacity can be tailored to the required humidification needs.

A evaporative humidifier operates using a water reservoir and a pump. The water is distributed over the humidification pack. The heat in the incoming air causes the water to evaporate. As a result, the air is both humidified and cooled during the evaporation process.

The air velocity within the air handling unit affects the system's performance. At higher velocities, water may be carried along with the air flow. You can prevent this by adjusting the air velocity or using a droplet eliminator. If the air velocity exceeds 3.0 m/s, Cumulus recommends the use of a droplet eliminator.

No adhesive is used during installation. This makes it possible to use any type of water for atomisation.

Advantages:

Suitable for use in any air handling unit
Short absorption path
Suitable for adiabatic cooling
Energy-efficient
Easy installation, de-installation and maintenance
Low operating costs
High efficiency

Legionella-safe humidification

For Legionella-safe humidification, Cumulus always recommends osmosis water. A reverse osmosis system removes viruses and minerals from the water, thereby preventing the atomisation of Legionella bacteria.