Based in the Allgau region of southern Bavaria, Bauer MAT Slurry Handling Systems is the wholly-owned subsidiary of Bauer Maschinen GmbH whose specialism is slurry mixing, pumping and separation technology.

Established in 1990 by Thomas Bauer and Manfred Kleimeier, with a view to supporting Bauer with slurry treatment, MAT has been at the forefront of developing state-of-the-art equipment in this specialist field of foundation engineering and tunnelling ever since. A recent rebranding introduced the MAT ‘Three peaks' core values; Solid. Easy. Performance. The inspiration came from the mountain views of the lower Alps, easily visible from the factory and represent the dependable, long-lasting and simplicity of the MAT product.

Colloidal mixing

One of the key differentiators of the MAT product range is its colloidal mixers. Colloidal mixing involves a high strength shearing force generated by the mixer paddles in combination with cavitation forces created by the mixers patented design. These combined forces allow a high dispersion rate of the solid particle which ends with a high-quality homogenous mix.

In the case of bentonite slurry, unlike other designs of mixing process, the slurry can be used immediately without the requirement of a 24-hour hydration period. This is also an important consideration when using bentonite in combination with other products for the slurry for a cut off wall. It is often the case that a two-stage mixing process could be required, i.e. mixing the bentonite in one mixing plant, allow it to hydrate typically for 24 hours and then combining it with the other solid materials in a second mixing plant. The MAT colloidal batch mixing plants make it possible to combine bentonite with the other products in one mixing operation for immediate usage, without excessive bleed occurring.

The latest version of this patented technology is available as part of the fully automated CMS 30 and CMS 45 containerised mixing systems. Launched at Bauma 2019, the CMS range follows Bauer's urbanisation theory of making equipment cleaner and easier to mobilise into urban job site environments.

Housed in a standard 20ft shipping container, the CMS units combine both a mixing and storage tank capable of batching either 30m³ per hour or 45 m³ per hour depending on the chosen unit. The integrated water tank allows for a faster mixing process. The latest mixing vessel design improvement incorporates an external large-diameter recirculation pipe which allows a continuous transfer of the slurry between the two internal mixing zones, resulting in maximum homogeneity of the finished slurry.

Component weighing system

Alongside this is the new version of MAT's component weighing system. With additional scales at three points, the loading of material is more accurate than ever thus reducing any overconsumption of both liquid and solid components helping to ensure the mix recipe is as accurate as possible.

Typical applications for the CMS units are, but not limited to, soil mixing (SCM and CSM), jet grouting, mini and micropiling, cut-off and soil mixing walls, to name but a few.

Considering that data capture is becoming an increasingly important factor for construction projects to allow the likes of BIM and other platforms to function adequately. MAT has introduced a fully digital, touchscreen control system for the CMS units. All batch data is stored and is downloadable via USB ready to upload in CSV format. The digital control system allows incredibly accurate control of the weighing process to ensure perfect component quantities are batched. This is achieved by the automated system directly controlling the output screw feeds of the solid component silos. Using the built-in VPN router, it is currently possible to gain remote access to the CMS units for diagnostic and analysis purposes.

In the future, it will also be possible to remotely download the batch data. Since the introduction of the first CMS unit at Bauma, MAT has built and sold 15 of these units to various parts of the world. So far the feedback is highly positive.

Muhlhauser Obermann takeover

Another recent major development for Bauer MAT Slurry Handling Systems was the takeover of the former Muhlhauser Obermann GmbH company. Originally founded in 1974 in Michelstadt, south of Frankfurt, Obermann's 15 remaining employers will now form a newly established company - Obermann MAT GmbH.

Although the takeover was only completed on November 1, 2019, Obermann MAT was able to ship its first orders last month; two DP-50 and two DP-63 grout injection pumps to a project in Bhutan and a VS-41 grouting unit to a customer in Portugal.

Obermann MAT offers an in-depth product range including powerful, innovative and highly reliable grout injection pumps, high-pressure jet grouting pumps and grout mixers among other things.

With over four decades of experience, Obermann has been at the heart of specialist foundation engineering and tunnelling projects for many years and is, therefore, able to offer a comprehensive technical solution for grouting and injection works for various applications, which complements the existing MAT product range.

Bauer MAT Slurry Handling Systems and Obermann MAT sales director, Timo Seidenfuss, said: "The introduction of the Obermann product range is an ideal addition to our existing range of equipment. The Obermann portfolio will allow us to serve existing markets even better and it also opens up opportunities in new sectors. By utilising the knowledge and experience of these two great companies we will be able to streamline our product range to deliver the best possible equipment to our customers.