The design of the magnetic filter was recently modified at a customer's request to include a sieve that filters out product impurities, such as paper, plastic particles and stones.
Liquefied chocolate
The sieve is normally a separate unit facing upstream in the magnetic filter in the production process.
In the modified design this was combined with the double-walled magnetic filter, to reduce operations, costs, time and heat loss. Both the magnetic bars and sieve can be cleaned in a single operation.
Speaking to ConfectioneryNews, application engineer, Arie van Dodewaard, who designed the filter said chocolate usually congeals when it’s transported under pressure but the third housing in the filter contains heated water which keeps the chocolate liquid.
"The second and middle housing of the filter is an air-filled space which gives extra protection and prevents the risk of water getting into the chocolate, which would result in the loss of an entire batch," he said.
"Normally a sieve is an extra product in the chocolate process. This takes out paper, plastic particles and stones for example. Now it’s integrated in the filter. This saves one step in the process and is now done at the same time as separation of the metal particles.
"An additional safety for this filter is a special closure of the lid so this cannot be opened without tools while under pressure. I’ve also added a special connection point for a pressure sensor. "This specific type of filter was launched in June 2018 and is available worldwide."
Guy Mutsaerts, sales manager, Goudsmit Magnetic Systems, said heating the filter housing with warm water keeps the chocolate liquefied.
“Major chocolate producers in France, Germany, the Netherlands and Belgium use double-walled magnetic filters in their process lines,” he said.
“These remove the metal particles from products that can congeal and are transported under pressure. Hot water flows through the outer wall, which keeps the product liquefied.”
The maximum working/product temperature is 140°C.
The neodymium-iron-boron magnetic bars present in the core, with a flux density of 10,700 gauss, capture the iron particles in the product, to make sure no contaminants make their way into the final product.
HACCP requirements
The magnetic filter is made of grade 316 stainless steel and meets HACCP requirements.
The filter is easy to implement in an existing pressure pipe, ranging from 10 to 15 bar. Seals are EC 1935/2004 compliant.
The magnetic filter is available in sizes DN50 to DN125.
The existing double-walled magnetic filter was also modified to include an additional wall, creating an air-filled space between the core through which the chocolate or mass flows and the cavity where the hot water flows.
This stops water getting into the chocolate, which could lead to the loss of an entire batch.