Filtration - Energy & District Heating

Efficient filtration in energy production and district heating

Filtration plays a crucial role in energy production and district heating production. In these demanding industrial environments, it is essential to remove impurities from liquids and gases to ensure operational reliability, energy efficiency and longer plant life.

At Nordic Filtration, we deliver advanced filter solutions that meet the high demands within the energy sector and district heating industry.

Why is filtration important in energy production?

In energy and district heating production, large quantities of water, steam, oil and chemicals are handled. Unfiltered particles can lead to:

   • Clogged heat exchangers and pipelines
   • Corrosion and wear on turbines and pumps
   • Reduced thermal efficiency
   • Unplanned downtime and expensive maintenance

By implementing correct filtration, the risk of these problems is minimized and the plants can run stably and efficiently for longer.

What types of filtration are used in energy and district heating?

Filtration needs vary depending on the process step and the medium to be treated. Typical filtration methods include:

   • Particle filtration of raw water and process water
   • Oil and fuel filtration for lubrication systems and boilers
   • Filtration of condensate and steam to protect turbines
   • Gas filtration in connection with biogas or natural gas
   • Side-stream filtration in district heating systems

The filtration process – step by step

Here is an overview of filtration in a typical energy plant or district heating plant:

1. Raw water intake and pre-treatment
Raw water from lakes, streams or groundwater is often used as process water. The first step is coarse filtration to remove leaves, sand and larger particles.

Filters used:
   • Basket filters
   • Bag filters

2. Boiler water and steam plants
Before the water is sent to boilers and heat exchangers, it requires fine filtration to avoid limescale, rust and sludge formation.

Filters used:
   • Cartridge filters (depth filters)
   • Reverse osmosis or water softening as pre-treatment
   • Magnetic filters to remove iron particles

3. Oil and lubrication systems
Generators, turbines and pumps use hydraulic and lubricating oil, which must be kept free of particles and water.

Filters used:
   • Pressure filters
   • Coalescer filters for water separation
   • Inline oil filters

4. Condensate and return water
In district heating systems, return water is recirculated. Here it is important to remove magnetite, sludge and corrosion particles.

Filters used:
   • Magnetite filters
   • Automatic self-cleaning filters
   • Side-stream filtration with fine filters

5. Gas conditioning
In biogas or natural gas-based heat production, gas filtration is used to remove oil aerosols, dust and siloxanes.

Filters used:
   • Gas coalescer filters
   • Activated carbon filters

Requirements for filters and filter housings in the energy and district heating industry

The products must meet strict standards in terms of temperature, pressure and corrosion resistance. Specific requirements include:

   • Stainless steel or epoxy-coated steel materials
   • Resistance to high temperatures and chemicals
   • Easy maintenance and replacement of filter elements
   • Compliance with standards such as EN 13445, ASME or PED

Nordic Filtration offers tailor-made filter solutions and advice for these needs. Our products ensure optimal protection of plants, reduce maintenance costs and increase uptime.

Eksempler på anvendelser af filtrering i et mejeri

• Indløb af mælk → grovfiltrering mod partikler
• Pasteuriseret mælk → membran- eller sterilfiltrering
• Yoghurtproduktion → koncentrering via ultrafiltrering
• Ostefremstilling → separation af valle og proteiner
• Isvand og procesvand → mekanisk og mikrobiologisk filtrering
• Trykluft til tappeanlæg → flertrins sterilfiltrering

Frequently Asked Questions (FAQ)

What is the purpose of side-stream filtration in district heating?
Side-stream filtration continuously removes particles from return water without affecting the primary flow rate. This reduces corrosion and ensures optimal heat transfer.

How often should filters in a district heating system be changed?
It depends on the filter type and load, but typically visual inspection and replacement every 6-12 months is recommended.

Can filters improve energy efficiency?
Yes. Clean heat exchangers and pumps work more efficiently, and proper filtration minimizes energy losses caused by deposits and flow restrictions.