FRIESS magnetic filters in heating and cooling water systems
Cooling water circuits and solar systems are often filled with water-glycol mixtures for frost protection reasons. Propylene glycol added to the water mainly serves as frost protection. The propylene glycol also provides a certain degree of corrosion protection. Due to the addition of propylene glycol, the viscosity of the circulation fluid used increases slightly and the air separation capacity deteriorates.
Problem
Particularly with the very low flow rates in solar thermal systems, air bubbles can form which reduce or completely inhibit the flow of liquid.
In a seven-year-old solar thermal system, the system had to be flushed to remove air bubbles that had formed over the years. Although the design of the system (corrugated stainless steel pipe and copper pipe) meant that the system was not expected to be contaminated with iron particles or corrosion residue, there was still significant contamination.
Solution: FRIESS magnetic filter
Flushing was carried out using a pump with a downstream FRIESS magnetic filter. After one hour of flushing, the flushing pump was disconnected and the system was put back into operation.
Despite the low total volume of only approx. 50 l, considerable quantities of fine ferritic particles were found on the magnetic filter rod.
By additionally equipping cooling water and solar circuits with a magnetic filter system, the ferritic particles present in the system are continuously filtered out and removed. This prevents deposits in the system, corrosion and pitting on sensitive stainless steel components, such as heat exchanger plates or thin-walled corrugated stainless steel hoses. Due to the simple design of the FRIESS magnetic filter systems type FMF, there are no additional costs for consumables or filter aids. Due to the high dirt holding capacity of the FRIESS magnetic filter systems, the magnetic filter system only needs to be cleaned once a year as part of the annual maintenance of the system.
Overview of the results of magnetic filtration
- the magnetic filter rod retained considerable quantities of ferritic fine particles
- Cooling water and solar circuits continuously filter out ferritic particles with magnetic filter system
- This prevents corrosion and pitting on stainless steel components such as heat exchanger plates or thin-walled corrugated stainless steel hoses