There are a range of different industrial mixing technologies, applications and methods. Cement mixers vary in size, shapes, arrangements and modes of operation but will nearly always be a continuous mixer or batch mixer. Continuous mixing and batch mixing are two different ways of mixing concrete and other products, each suited to different circumstances.

As the name suggests, continuous mixers allow you to continuously load, mix and discharge concrete until the required amount is achieved. Materials are loaded in manually using screw feeders. Continuous mixing is ideal for large scale projects such as constructing major roads, high rise buildings, dams or bridges.

Batch vs Continuous Mixing

With batch mixers, all the ingredients are loaded into the mixer together or in a pre-defined sequence. It’s a three-step process that begins with weighing and loading the components. The batch mixer then mixes everything together until a homogenous material is produced, which is then discharged in one lot from the mixer. Batch mixers are suitable for contractors who need small loads of concrete or mortar for domestic construction projects. Its output is measured in kg per batch.

Continuous mixers on the other hand are dedicated to producing a single high-volume product. Ingredients are continuously fed to the mixer according to a formula, with the mixing taking place as the material moves from the charging port to the discharge nozzle. The output is measured in kg per hour, and continuous mixers can be designed for capacities as high as 500 tons an hour.

How Continuous Mixing Works

The movement the feeding point to the discharge point is caused by the rotation of mixer vessel, which rotates the ingredients or moves them down in a zig-zag pattern like a continuous paddle mixer. The process of charging the material is extremely important and can significantly affect the quality of the discharged mix.

Axial and radial mixing takes place as the material travels through the mixer. The time it takes for the material to move from the feeding point to the discharge point is called the retention time of the mix. Retention time of the product can be carefully controlled in batch mixers, but it isn’t uniform in continuous mixers. It can be affected by things like the feed rate, mixer speed and the design of the mixer.

Benefits of Continuous Mixing

Continuous mixers have a range of benefits, including:

  • High capacity compared to batch mixers
  • Lower mixing time compared to batch mixers
  • Consistent mixing performance with proper feeding arrangements
  • Automated control capabilities
  • Reduced segregation of particles in the mix
  • Lower cost of mixers
  • More compact than batch mixers
  • Less labour compared to batch mixers

Disadvantages of Continuous Mixing

There are some downsides to using a continuous mixer, such as:

  • Doesn’t mix as well when there are a lot of ingredients introduced
  • Higher overall maintenance costs
  • Requires careful calibration and checking
  • Not suitable for situations where product formulations must be perfect
  • Lack of flexibility, as the system needs to be recalibrated to mix a new formula or if a new ingredient is introduced

Quality Concrete Mixers in Australia

If you’re looking for a continuous concrete mixer with a pump for sale, a mobile concrete mixer truck or other mixing plant, get in touch with the experienced team at Batchcrete. From mini concrete pump hire to screed mixer hire and much more, we understand the complex nature of the industry and provide concrete equipment to suit a variety of needs, with the option of tailor-built solutions. Call us today on 08 9463 5355 or contact us online for high quality, cost effective concrete supplies.