Use of Homogenizer in Making Grease


Since ancient times, there has been a need for lubrication of mechanical parts. The Egyptians used sheep and cattle fat to reduce axle friction in their carts as far back as 1400 BC. Ancient axle hubs tried more complex lubricants by mixing oil and lime, but these lubricants were in no way equivalent to modern grease oils. Greases capable of good lubrication did not exist until the development of petroleum-based oils in the late 1800s. Nowadays, many different types of grease oil are produced, but the basic structure of these greases is similar to each other.

Generally, there is a thickener/jelling agent dispersed in grease oil. Thickeners or jelling agents can be alkali metal soaps, clays, polymers, carbon black, colloidal silica, and aluminum complexes. The lubricating oil can be petroleum oil or synthetic oil. The most common type of grease is soap-based grease.

In soap greases, the metallic soap consists of a long-chain fatty acid neutralized by a metal such as aluminum, barium, calcium, lithium, magnesium, sodium, or strontium. To properly thicken the grease, the soap must be in the form of fibers of the appropriate size distributed in the lubricating oil. The crystalline fibers are generally in the range of 1 – 100 micrometers in size, with diameters between 0.1 and 0.01 mm of their lengths. To obtain a good grease oil, the length/diameter ratio needs to be high, and for good oil retention, the fiber needs to be as small as possible

Production of Grease Oil

Stages of Grease Lubricant Production:

  • The components of the oil are measured or taken into the processing reactor.
  • For soap-based greases, the oily content, alkali, and a portion of the oil are added to the reactor.
  • By heating (150-230°C) and stirring, the oil is converted into soap and the soap is distributed throughout the mixture. This can be done in an open water heater or closed pressurized water heater.
  • Once saponification and dehydration (removal of water) are completed, the remaining oil is added to the batch to lower the temperature.
  • The grease is milled and homogenized.

The Importance of Homogenization in Grease Oil Production

The homogenization step is very important in the grease production process because a uniform crystal and gel structure should be produced that will not change when the grease is used. Homogenizing the grease will homogeneously distribute the small particles resulting from the breaking down of solid particles or fibers contained in it throughout the liquid. This fragmentation process will also minimize agglomeration. It will ensure the production of a smooth product by eliminating large particles. The homogenization of certain types of greases hardens the grease, providing a lower penetration value. Homogenization can improve texture and brighten the appearance of a grease. The homogenization process is usually carried out at temperatures above 80°C.

Use of HOMMAK Homogenizers in Grease Production

Homogenizers are used to process grease oil. HOMMAK Homogenizers can operate up to 1500 bar with materials resistant to wear. The homogenizer is the preferred equipment for greases containing substance additives because high energy is required to break down and separate parts like clay dispersions. While a colloid mill can be used to process grease, it is more advantageous to use a high-pressure homogenizer.

Advantages of High-Pressure Homogenizer

  • The homogenizer is a constant displacement pump and its capacity does not change according to different grease grades. This makes it possible to connect to filling equipment if desired. The colloid mill requires feeding by a pump and its capacity significantly decreases in harder grease grades.
  • The high-pressure homogenizer has enough pressure to deliver the grease to any point of the process after homogenizing it. However, if the grease is to be sent somewhere else, a second pump is required to take the colloid mill product.
  • Due to the reduction in particle size, the reaction time can decrease by 4-5 times. This provides significant energy savings.
  • It enables the production of a more consistent product with mechanical stability.