13.12.2016

A container mixer that does it all: Mix at the highest level with flexibility and no contamination

It doesn't matter if it's the instant coffee in the morning, the protein shake before exercising or the candy bar in between - almost all processed food that we consume during the day is made up of numerous different ingredients. So that these individual components can be optimally combined at the end into a consumable product, a mixer is used in almost every production. Mixing technology is all about mixing the ingredients of a recipe as quickly as possible, uniformly and without damaging the product - so that the qualitative features of the end product such as consistency, texture, color and taste are identical in every mixture.

Only the mixture procedure optimized for the respective recipe means that our favorite candy bar tastes as good as usual and that the 3-in-1 coffee powder dissolves without clumping every morning. The replication of important product features ranging over the different batches is essential for a consistently high quality end product.

This example case is about a Croatian business which produces coffee products, functional dietary supplements, snacks and also baby food, and personal hygiene products. During production, primarily bulk solids such as milk powder, sugar and various flakes are processed into uniform mixtures. For this task they were looking for a suitable mixing procedure. J. Engelsmann AG provided this manufacturer with a high quality mixer for a similar purpose back in the 90s and so they were requested once again.

During a visit to the Slovenian production site, the customer requirements as well as how the mixer was to be integrated into the production process were explained. In addition to a uniform mixing result, the customer also required primarily contamination free procedures, a simple process as well as more flexibility to switch production for different products - requirements which the container mixer JEL CM by Engelsmann could meet without compromise. This mixer is made principally from a frame construction with a build in motor, a container pick-up fork, the actual container as well as a control cabinet with user display. In this definite case, the customer didn't need any additional container because he already had several in use with a load capacity of 1,000 liters. In these containers, the ingredients according to the end product or recipe are collected before they are mixed together. The measures and weight of the container had to be recorded beforehand so that the mixer's pick-up fork could be adjusted accordingly. To be better positioned to assess the properties of the products that are to be mixed and to guarantee a perfect end result, a trial construction was built in Engelmann's technical center before the order was even assigned. After the mixed product sample had been tested in the food manufacturer's lab and received good results, the order was assigned and the container mixer was completed.

The mixing process in detail

The mixer is loaded by sort of lifting the container where the respective ingredients are gathered at the forefront. A fork lift lifts this up and takes it to the mixer where the filled container is emptied into the open pick-up fork. If the central band of the container fits securely, the interlocking clip is closed around the container and secured with a hand wheel. It's only once the fork lift comes out of the rotary range of the mixer and the barrier for the pentice is locked that the mixing procedure can start. Then the operator just has to type in the desired mixing time and rotation speed in the touch screen which is built into the control cabinet. The pickup fork is then rotated by the motor. The 30/60-degree position of the container's side walls to the rotational axis creates a tumbling motion which means that the individual components are distributed evenly according to the principle of free-fall mixing. The product particles are pulled up, then they either slide or fall back down into the material being mixed, which makes for intense blending even for the smallest amounts. From this rotation and the tilted positioning of the container wall there is also a particularly protective mixing effect which is based on the interplay between friction and the force of gravity - without using a mixing aid. Four hydraulic clamping devices onthe pick-up fork ensure that the container stays securely anchored to the fork during the mixing process. Drops in pressure are caught immediately thanks to the built in pressure regulator so that the container is automatically retightened. If there is a complete drop in pressure, then the mixer turns itself off for safety reasons. Once the specified mixing period is over, the container stays in the starting position. After the operator has opened the interlocking clip, the mixing vessel can conveniently be removed by the lifting truck and moved to the next processing step. The operator can insert the next container without any additional cleaning effort - it doesn't matter if it is for a different recipe. This provides the highest level of flexibility in the production since it can be adapted quickly to other products. The container used has many functions from being loaded to being emptied: it acts as a transport vessel before and after mixing, as a container during mixing as well as a feed container for the next production stages which, in addition to the economic benefit, also makes it possible to trace the batch back. What is special about container mixing is that the chance of product contamination can practically be excluded as it is a sealed system where foreign bodies can get in at no point. Even in the strictly regulated food industry, this aspect is incredibly important for manufacturers because violations of the legal regulations carry the threat of high penalties and compensation payments, never mind about the damage to the image. As well as product safety, the operator's safety is the highest priority, a pilot light was built into the control cabinet which by going green or red signals whether the mixing process is in progress and when it is safe to enter the mixer's rotary range.

As well as mixing solids the JEL CM can also be used for special purposes such as for dissolving solids in liquids, polishing parts made of metal or plastic, moving sluggish media to avoid structural change and cleaning containers with solvents. The fact that it can be operated without the risk of contamination as well as having the options of ATEX and GMP designs and that it can be adjusted to different container sizes and products makes the container mixer a real all-rounder which has advantages for other industries as well.

After an adventurous delivery in Slovenia where the machine had to be lifted into the second story of the production hall by crane, a team from Engelsmann supervised its assembly and trained and instructed the operating staff. Thanks to the machine being put into operation seamlessly and the increased flexibility in his factory, the operator is now considering equipping his other production centers with JEL CM mixers as well.