How does the filter-demulsifier work? Differences between a mesh filter and a filter-demulsifier

In modern heating and cooling systems, the quality of the working medium, i.e. the water circulating in the system, plays a key role. Solid contaminants, sediment and ferromagnetic particles can significantly reduce the performance of the entire system, leading to costly failures. That's why there is an increasing use of filter-demulsifiers - devices that effectively eliminate the problem of contamination in hydraulic systems. How they work and how they differ from classic mesh filters? We invite you to read.

What is a filter-demulsifier?

A filter-recirculator is a filtration device designed to remove solid contaminants from liquid flowing through a system. Unlike classic mechanical filters, which are based mainly on grids that retain particles of a certain size, filtermultipliers use hydrodynamic phenomena, gravitational separation, and often magnetic fields.

The primary tasks of the filter-demulsifier are:

• Retention of solid contaminants (e.g., sand, scale, metallic deposits).
• Separation of ferromagnetic particles using permanent magnets.
• Reducing the risk of corrosion inside the installation.
• Preventing damage to pumps, valves and heat exchangers.

Thanks to their multi-stage filtration, the filter-demulsifiers are extremely effective in purifying water in central heating systems (c.o.), district heating, refrigeration and in systems using glycol as the working medium.

What's the difference between a filter-demulsifier and a mesh filter?

At first glance, the mesh filter and the filter-recirculator perform a similar function - they are supposed to protect the installation from impurities. However, the differences in their design and principle of operation make the filter-demulsifier a more advanced and effective solution.

The key advantage of the filter-demulsifier over the mesh filter is its ability to separate contaminants in several ways, which increases its efficiency and extends the periods between necessary service work.

In which installations are used filtermultipliers?

Filtro-demulsifiers are used in many types of installations where maintaining the quality of the working medium (usually water) is crucial to the reliability and efficiency of the system. The following are the most important areas in which the use of filter-demulsifiers brings tangible benefits:

1. Central heating installations (c.o.)
   In systems c.o. the filter-demulsifiers act as the first line of defense against contaminants that may settle on components such as heat exchangers, boilers or pumps. Thanks to the use of multi-stage filtration - combining inertial, sedimentation and magnetic effects - these devices effectively remove both solid and ferromagnetic particles. The result is:

   • Increase thermal efficiency, by preventing scale buildup,
   • Extend the life of equipment, thanks to protection against corrosion and mechanical wear,
   • Reduction of service costs resulting from a lower frequency of failures and downtime.

2. Thermal nodes and district heating networks
   In larger installations where the flow of the medium is intensive, filter-demulsifiers are installed at strategic points - often directly in front of heat exchangers or in areas where the flow is split. Their use allows:

   • Minimize the risk of clogging hydraulic systems, which is particularly important in high-capacity district heating networks,
   • Keep the flow parameters stable, thanks to low pressure losses,
   • Facilitate the maintenance of the installation, as the cleaning of equipment is done in a systematic and predictable manner.

3. Cooling systems and air conditioning systems
   In cooling and air-conditioning systems, where high purity of the medium is required, filter-demulsifiers contribute to:

   • Protection of pumps and heat exchangers against the accumulation of deposits that could affect cooling efficiency,
   • Maintain optimal system performance, by eliminating contaminants that can cause pressure drops or flow disturbances,
   • Increasing the reliability of the overall system, thanks to regular separation of particles and minimization of the risk of failure.

4. Industrial and process installations
   In industry, where technological processes often require a very clean medium, filter-demulsifiers are used in:

   • Cooling systems for machinery and production equipment, where deposits can affect accuracy and quality of work,
   • Process water treatment systems, where the presence of contaminants could lead to damage to precision equipment,
   • Process lines, in which the purity of the medium translates directly into the quality of the final products.

5. Glycol systems and solar heat cycle installations
   In installations that use glycol or other mixtures, filter-demulsifiers help:

   • Maintain the thermal properties of the medium, by removing contaminants that could degrade its flow parameters,
   • Prevent degradation of materials, from which heat exchangers and other plant components are made,
   • Maintain thermal stability, which is crucial for the efficiency of the whole system.

6. Water supply systems and secondary filtration systems
   In some cases, filter-demulsifiers are used as a supporting element within larger water treatment systems:

   • In systems working with de-ironers or hasty sand filters, where multi-stage filtration provides a very high quality medium,
   • As bypass filters - serving only a portion of the flow (usually 5-8% of the nominal flow), which allows continuous operation of the system with minimal impact on the main circuit.

In summary, the filter-demulsifiers are versatile filtration devices that are used not only in central heating systems, but also in industrial, refrigeration, air conditioning and water supply systems. Their use allows comprehensive protection of the installation from contamination, which consequently leads to an extension of the life of equipment, increased energy efficiency and lower operating costs. This makes them an indispensable part of modern technological systems, where precision and reliability of operation are crucial.

How to properly select a filter-recirculator?

The selection of a filter-demulsifier is a process that is worth carrying out taking into account both the technical parameters of the installation and the type of contaminants that may be present in it. Below are the most important aspects to pay attention to:

1. Pipeline diameter and flow rate

   • The first step is to match the size (DN) of the filter-recirculator to the nominal diameter of the pipeline. If, for example, the main line has a diameter of DN65, it is best to choose a device with the same nominal diameter.
   • The flow velocity in the system should not significantly exceed 1 m/s to avoid excessive pressure losses. Too high a speed can also impede the sedimentation process of contaminants, which will reduce the effectiveness of de-sludging.

2. Characteristics and amount of pollution

   • It is worth analyzing what types of sludge dominate the installation. If ferromagnetic particles prevail (e.g., corrosion products of steel), magnetic cartridge filter-recirculator will be particularly useful.
   • In situations where the water contains a lot of mineral particles (sand, limescale), attention should be paid to the design of the filter mesh and the possibility of easy access to the interior of the device for frequent cleaning.

3. Operating conditions: temperature and pressure

   • Each filter-demolisher has a specific temperature range and maximum operating pressure in which it can safely operate. Make sure that the selected model is adapted to the real parameters of the installation.
   • High temperatures (above 100°C) or increased pressure require equipment made of suitable materials (e.g., carbon steel or stainless steel) and special seals.

4. Pressure losses and hydraulic requirements

   • The filter-recirculator should be sized so that it does not introduce excessive pressure losses in the system. Too much pressure difference can interfere with pumps or heat exchangers.
   • As a rule of thumb, it is assumed that the pressure drop across the filtermultiplier should not exceed 0.5 bar, but the exact value depends on the specifics of the installation and the manufacturer's requirements.

5. Maintenance method and frequency

   • Ease of access to the device and the ability to quickly remove deposits are key operational considerations. In installations with a large amount of pollution, it is worth choosing a filter-demulsifier with a larger settling tank, so that it does not have to be cleaned too often.
   • Models with replaceable filter cartridges or with protective sleeve for magnets can significantly reduce plant downtime during maintenance.

6. Installation layout and location

   • Most often, the filter-recirculator is installed at the return of the heating system (c.o.), in front of the boiler or heat exchanger to maximally protect key equipment.
   • In elaborate systems, you may consider installing bypass filter (known as by-pass), especially in larger district heating networks or heat exchanges.
   • You should also include enough space to perform inspections and cleaning. Too tight can make proper handling difficult or even impossible.

7. Compliance with standards and guidelines

   • It is worth checking that the selected model has the required approvals, certificates and meets industry standards (for example, for pressure equipment).
   • If the installation has specific design guidelines (e.g., in public or industrial facilities), the selection must be adjusted to meet these requirements.

8. Operating costs and long-term savings

   • The purchase price of the device is just one factor. Equally important are the cost of servicing, the frequency of replacement of consumable parts, and possible plant downtime.
   • Higher quality workmanship can translate into longer life and less risk of failure, which in the long run saves real money.

In summary, the correct selection of a filter-demulsifier requires an analysis of the entire hydraulic system, operating conditions and the type of contaminants. A well-considered decision in the design and installation phase reduces subsequent maintenance and repair costs, and above all ensures stable and efficient operation of the system for many years.

Filter-demulsifier service

In order to operate effectively, the filter-demulsifier requires regular servicing. The cleaning process consists of several steps:

1. Closing the flow of water in the system (or cut off the device, if valves are installed).
2. Opening the tank lid and removing the mesh filter and magnetic cartridge.
3. Cleaning of filter elements - rinse the net and magnets with water under pressure.
4. Removal of sediment from the lower part of the tank - usually through a drain spigot.
5. Reassembly and bleeding of the system once the installation is up and running.

Regular maintenance of the filter-multiplier prevents the accumulation of dirt and ensures its full efficiency for a long time.

Summary

Filtroodmulators are indispensable components of modern heating and cooling systems. Unlike classic mesh filters, they not only retain contaminants, but also effectively eliminate ferromagnetic particles and reduce the risk of corrosion. Their use allows to significantly improve the energy efficiency of the system and reduce service and operating costs.

If you are looking for an effective solution for your installation, it is worth considering the purchase of a filter-recirculator tailored to its parameters. We invite you to familiarize yourself with our offer, in which you will find devices that meet the highest standards of filtration.