New homogenizer, new pressure
It’s a common mistake to buy a new homogenizer with the same pressure and capacity as your existing unit. But keep in mind that homogenizers are getting more efficient all the time, and what was the right pressure a few years back might be excessive now. Don’t just think in terms of required pressure and capacity, but ask yourself what product properties you want to achieve with homogenization.
An important question to ask yourself is whether you should choose a hydraulic or pneumatic pressure setting. Experience has shown that a hydraulic system is more repeatable and accurate than a pneumatic system. So a pneumatic system could result in higher production costs or uneven product quality.
A matter of time
Will you run the homogenizer 24/7, or just one shift a day, or perhaps just a couple of months per year? The answer matters because the homogenizer with the lowest investment cost might not be the right one if uptime is important. A larger model offering longer service intervals might actually be the better choice. Then again, once it’s time to change pistons and seals, a five-piston machine will of course require more spare parts than a three-piston machine.
Partial to milk?
Is the homogenizer to be used to produce chilled milk? Then remember to consider partial homogenization. Partial homogenization means that a stream of 18% fat gets homogenized while the skim milk bypasses the machine. By doing this a smaller model can be selected and the investment cost and running costs are reduced.
The heat is on
Are you going to run the homogenizer downstream? If so, it should be an aseptic design with high temperature condensate flushing over the pistons. This is important for food safety. If the temperature is below the pasteurization temperature of 75°C, there is a risk for reinfection over the pistons. Some suppliers offer low-temperature condensate as their seals would not survive the higher temperature. But these solutions require high water consumption and result in high running costs, compared to a high temperature condensate.