While we spend a lot of time in this blog talking about Waukesha’s Universal Series PD and centrifugal pumps, and more recently about Graco’s industry leading AODD pumps, today we wanted to talk about another kind of pump-like process equipment we love to help customer’s with- High-Pressure Homogenizers.
People hear the word “homogenizer” thrown around all the time, but what people think most about them is either that their product needs to go through them for some reason or that it’s been there forever and hard to find parts for. In today’s post, we’re going to provide an overview from 30,000 ft. of what high-pressure homogenizers are (in layman’s terms) and what you need to know to get a quote for one.
To start, what is a high-pressure homogenizer? Well actually, let’s just start with what is a homogenizer? A homogenizer can refer to a number of different pieces of industrial equipment that take two or more non-soluble liquids and combines them to make them the same throughout. Different pieces of equipment that could be considered homogenizers are things like high shear mixers, colloid mills, shear pumps, and DTL blenders.
But the most common type of homogenizer- and the one we’ll spend the rest of this blog talking about- is a high-pressure homogenizer, otherwise known as a “Gaulin” homogenizer. High pressure homogenizers, while big and often confusing, are actually quite simple. High pressure homogenizers have been around since the early 1900’s and are made up of two basic parts- a high pressure triplex plunger pump and a valve (sometimes two). That’s it- a high pressure-homogenizer is just a pump and a valve.
A high-pressure homogenizer works by taking a product feed stream and then using that high pressure plunger pump to force it into the valve, which is really just a very tiny variable orifice, creating a very high pressure- typically between 2000-3000 psi, resulting in product homogeneity.
The oldest- and probably still most common- application for high-pressure homogenizers is milk processing. Nobody’s gallon of milk comes from just one cow- it’s a blend of milks from a number of cows and herds. So to manage the variety, milk is first standardized to get a consistent amount of fat throughout the product. The trouble is that this fat will usually separate out from water and collect at the top. Not something a shopper wants to see in the cooler at Walmart. So raw milk is fed through a high-pressure homogenizer to break the fat globules into smaller sizes, so it no longer separates and is a shelf stable product.
Other common applications for high pressure homogenizers include ketchup and salad dressing applications, baby formula, egg products, nutritional supplements, and flavorings. High-pressure homogenizers are also widely used in less sanitary, more industrial applications like grease manufacturing for their ability to reduce particle size and improve product texture and consistency. Accordingly, we’ll sometimes hear homogenizers referred to as “mills”.
One last application we’ll touch on are high pressure feed applications, like spray dry feed applications. As we mentioned above, a high-pressure homogenizer is just a pump and a valve. So if we remove the valve, we’re left with a great high-pressure pump that is able to handle the high pressures required to feed various pieces of processing equipment.
So if you think a high-pressure homogenizer is the right piece of equipment for your application, what do you need to know to specify one? It goes mostly without saying that the first thing you’ll need to know is what product you want to run and the general operating environment.
Then you need to know your flow rate- how much product do you need to process (typically in an hour).
Finally, you need to know what pressure you need to homogenize at. Typically, end users will have an idea what pressure they need to run at. Otherwise, Triplex and APV Technical Specialists have an application database we can pull from to get you pretty close.
But what if it’s a new product or a product that hasn’t typically been run on a high-pressure homogenizer before? In those cases, we recommend using one of APV’s Pilot or Lab machines (like the APV 1000 or 15MR) to run product trials at different pressures and determine what your sweet spot is for throughput and product quality.
And that’s about all there is to getting started with specifying a unit- know a little bit about the operating environment and the product, know the flow rate, and know the homogenizing pressure. Triplex Sales Engineers can help you take it the rest of the way from there.
So that’s the high level overview of high-pressure homogenizers. While they can be big and scary, remember- they’re really pretty simply. Just a pump and a valve. And as always, if you have any questions about your sanitary process application or high-pressure homogenizer, please contact a Triplex Sales Engineer today!