The requirements related to Pressure stations depend on the size of the station and its location. From small remote communities to separate pressure zones in cities that guarantee rapid response to contamination scenarios.
condensation is one challenge
The task of the pressure rising station is to increase the pressure in the transport of drinkingwater over a distance. The stations are built both above ground and below ground. The stations are dimensioned for current requirements for flow and pressure increase.
One challenge with pressure stations is the condensation that will be on surfaces of cold pipes in the station. Even if the air feels dry, there is water in the air! Warm air can hold more moisture than cold. This means that the moisture present in the “dry” air is deposited on the surfaces of the pipes, typically having a temperature below 10°C.
That temperature on the coldest surface in the room will be the defacto dew point and will define the relative humidity level (RH) needed to avoid condensation.
Warming up the air in the station will thus not keep condensation away as the water in the air is still there. What is needed is to remove water from the air to a level suitable for the temperature on the cold surfaces.
We recommend to avoid any unnecessary warming up of the the station and let the dehumidifier secure a good humidity level.
Return of Investment example
Maintaining a warm pressure station using a typical electrical element consumes between 10,000 – 12,000 kWh per year based on the data we have available. An Airwatergreen dehumidifier consumes on average significantly less than 3,500 kWh per year. Rather under 2,000 kWh in the installations where our customers have measured the power consumption. This provides with a substantial energy saving of between 8,000 – 10,000 kWh per year! How much money will that add up to with your price/kWh and the numer of stations you are operating?!
In addition, you of course reduce the costs of renovation by eliminating corrosion, damage to electronics and mold!
The right moisture level
What is needed is a controlled humidity level below 60% relative humidity (RH) to avoid corrosion and mould but also to reduce bacterial growth. A relative humidity at the temperatures that can cause condensation on the cold pipes – not in the air otherwise.
See the Mollier chart below where the curve for condensation (saturation) is indicated as 100% RH at different temperatures.
Lowering the temperature in the air holding 50%RH to 10C will increase the relative humidity level to near 100%.
We recommend having a dew point sensor connected to our air dehumidifier for pressure stations. In this way the temperature of the coldest surface in the room (the pipes) control the dehumidifier in an optimal way to extract the water needed to avoid condensation and any damages from humidity.
Plug’n play installation
We do not need to install any unnecessary ventilation pipes and our dehumidification technology is as energy efficient at low temperature. The dehumidifier can be mounted on a wall bracket which allows it to be easily mounted on the wall so that the floor is kept free in the station building. Regular 1-phase 230V plug is enough to get started. The water is easily handled with a hose to a swamp or other runoff. If there is no run-off, it is possible to dissolve with a collecting vessel or pump to divert the condensate.
The Airwatergreen dehumidifiers are built to withstand the tough environment that applies and well thought out material choices and an IP63 classification. The air passing through the dehumidifiers not only dehumidified but also filtered so that dust and insects are caught.
PRODUCT CHOICES
Our smaller dehumidifier is called FLEX and has a capacity of 5 liters of water/day, which is more than sufficient in a normal-sized pressure boosting station.
A typical configuration includes:
- Dehumidifier FLEX type Smart or FLEX Integrate
- Wallmount
- Dewpoint
- Service agreement
REFERENCES
Airwatergreen currently has a large number of installations in pressure stations. In some cases the dehumidifier works independently against the set dew point and in other cases it is connected to an existing monitoring system which either only monitors the dehumidifier or controls it.
The products are built to withstand the tough environment that applies with few moving parts and well thought out material choices and an IP63 classification. T
he air passing through the dehumidifiers not only dehumidified but also filtered so that dust and insects are caught. It creates the conditions for a good work environment!
Do not hesitate to contact us for a climate investigation to define the moisture levels and to design a suitable solution for your business!