The Newland
Atomiser is a high-speed rotary atomiser which
produces very small droplets from water at ordinary temperature
and low pressure. When surrounded by a moving airstream the
droplets evaporate, producing humidity in the easiest way
possible. Because no heating or boiling is involved, the process
gives large energy savings over steam-based systems. And because
the Atomiser is small it can be installed almost anywhere,
without expensive pipework or cabling.
* No steam
or compressed air
* Very low
power consumption - less than 50 Watts @ 10 kg/hour!
* Low maintenance
* Tolerates hard water
Mounting:-
The Newland
Atomiser is usually mounted in the vertical orientation
shown, and measuring only 150 x 65 mm (6" x 2½")
is small enough to fit inside most ductwork and even the smallest
AHUs. A Mounting Kit is available from Newland
Design.
Water Supply:-
The water supply should be of low pressure, 0 - 6 barg.
Filtration
is unnecessary unless
there are significant amounts of undissolved particulates
in the supply.
Moderately
hard water does not cause a problem for the Atomiser. Because
the Atomiser does not actually evaporate the water, the salts
remain in the water until the water evaporates, downstream
of the Atomiser. Thus a deposit of these salts may accumulate
downstream.
In locations
where there is a very high concentration of salts (>~200
ppm), some encrustation of salts on the Atomiser's Spray Head
however may occur, but the Spray Head is an inexpensive, disposable,
easily replaced part.
The input temperature
of the water is usually unimportant; although warm droplets
will evaporate more quickly, this does not justify pre-heating
of the water. Maximum savings in capital outlay and in running
costs are obtained simply by using the water supply given.
Legionellosis:-
In applications where
there is risk of Legionellosis, caused by unevaporated ultra-fine
water droplets carrying infection, being ingested into people's
lungs, disinfection of the water supply (eg. by U/V sterilisation)
must be incorporated.
Power Requirement:-Low
power consumption is perhaps the greatest benefit of the Newland
Atomiser Humidification system with the only energy
requirement being to rotate the small spray head and break
the water up into droplets.
The Atomiser
operates from low voltage DC and consumes less than 50 Watts.
Newland Design
manufacture a suitable Power Supply designed specifically
for the Atomiser, providing the 10 - 25 VDC, 50W required
(also the 12 VDC, 2.5W required by the Solenoid Valve). One
Power Supply is required per Atomiser. A 24 VDC battery supply
is also acceptable.
The Newland
Design Power Supply provides a speed control;
although for humidification applications it is usual to operate
at or near full speed, for certain applications (eg.disinfection,
moisturisation) where full evaporation is undesirable, the
Atomiser's speed should be reduced, providing a larger droplet
size.
For installations
of more than ten Atomisers, a single DC Power Supply can be
a more economical alternative to having one Newland
Design Power Supply for each Atomiser:
contact Newland Design
for recommendations specific to your application.
Flow
Rates & Steam Equivalent:-
In most situations one Newland Atomiser
can deliver an equivalent of 10 kg/hour or more. The maximum
flow through the Atomiser in a particular application is determined
by: the velocity of the surrounding airstream; the distance
downstream of the Atomiser before any eliminator or significant
constriction; the airstream temperature. Contact Newland Design
for recommendations specific to your application.
Downstream
Distance:- Allowance
should be given for an evaporation time for the droplets of
one second or more, so that with an air velocity of eg., 1
metre/sec, a distance downstream of 1 metre should be allowed
for before any eliminator or significant constriction &c..
Cooling Effect:- The
evaporation of the water droplets from the Atomiser does of
course take the latent heat of evaporation from the airstream,
but in situations of moderate flow rate, this cooling effect
is negligible.
Multiple Atomiser Installations:-To
achieve steam equivalents of significantly more than 10 kg/hour,
more than one Atomiser will be required. These should be spaced
evenly and as far apart within the airstream as the AHU or
other mounting space allows. Typically a minimum spacing is
about 200 mm.
Control Regime:-The
Newland Atomiser works
best in a simple on-off mode, controlled by humidity demand.
Although modulation of the water flow rate is quite possible,
the expense and complexity of this are usually unnecessary.
The Atomiser does not mind being switched on and off; response
from switch-on to droplet emission is typically no more than
2 seconds.
In installations
of multiple Atomisers however, proportional response to an
analogue humidity demand may be achieved by switching on individual
Atomisers in stages. Any BMS control panel should be able
to accommodate this, with one relay output switching each
Atomiser or group of Atomisers.
Accessories:-
A typical installation
per Atomiser will require (all accessories are now available
from Newland Design):
* Atomiser
* Power Supply
* Mounting Kit
* Solenoid Valve
* either Metering Valve or Dosing Valve
* Flexible Tubing, 5 mm bore.
There are two alternatives available from Newland
Design for flow control: the Metering Valve
includes both a Needle Valve for flow control, and a visual
indication of flow (0 - 18 litres/hour), operating on ball
float within tapered tube principle; alternatively the Dosing
Valve, which is specially capable of precise control of low
flow rates (as low as 1 droplet per 10 seconds), but gives
no visual indication.
Installation:-
The system is easily assembled and intended for on-site installation by the customer,
or contractor. Quick instructions as well as full Technical
Data on the Atomiser are supplied as required with each system.
Newland Design
also offer on-site Installation and Maintenance visits.
Maintenance
& Spare Parts:-Typically it is necessary
to inspect the condition of the Atomiser no more frequently
than every three months; in installations where water quality
is high the interval may be indefinite. Spare Spray Heads,
available from Newland Design
are inexpensive and disposable and usually can be removed
and replaced without dismounting the Atomiser.