Adding a pigment color to a dynamicmixer that is also used for non-colored products creates color contamination of the wetted parts and results in increased labor as well as production time and yield losses that directly affect the bottom line. The Kenics®KM Series static mixer, manufactured and marketed by Chemineer, Inc., provides an alternative solution to addingpigment color that eliminates typical contamination problems and improves the quality of the finished product.

The Situation

A manufacturer was using the same dynamic mixer to process different batches of material. Some of the batches required the addition of a pigment color while other batches required no colorant adder. As expected, the pigment colorants contaminated all wetted surfaces that they came in contact with, including all wetted end dynamic mixer components. Regardless of the thoroughness of the cleaning process between batches, this situation still resulted in high yield loss of the batches that were processed immediately after a pigmented batch, and oftentimes production of a defective end product from contaminated batches that went unnoticed. In addition, the cleaning process itself resulted in lost production due to system flush down time of the wetted surfaces and the resulting system drain down time post cleaning.

The Solution

Chemineer, in conjunction with The DEN Group, recommended an innovative process solution that eliminated contamination of the wetted surfaces associated with the dynamic mixer during processing. A Kenics KM Series static mixer was installed inline just prior to the packaging component of the processing system, allowing the pigment color to be added at this point in the process, completely avoiding the dynamic mixing process. The addition of this motionless mixer at this point in the process eliminated all of the inherent problems that had been encountered with the previous processing system.

Kenics KM Series static mixers feature a patented helical mixing element that produces complete radial mixing and flow division for any combination of liquids, gases or solids. In all the mixers, a patented helical mixing element directs the flow of material radially toward the pipe walls and back to the center. Additional velocity reversal and flow division results from combining alternating right- and left-hand elements, thus increasing mixing efficiency. All material is continuously and completely mixed, eliminating radial gradients in temperature, velocity and material composition. Numerous independent studies have shown that Kenics static mixers maximize mixing efficiency without the wasted energy and material blockage typically found in more restrictive motionless mixers.

The Result

Introducing the pigment colorant through the Kenics static mixer that was placed near the end of the processing line resulted in significant savings in maintenance time, reduction in the amount of scrap or wasted material, and an increase in production rates and productivity yield. In addition, capital costs and installation costs were minimal, and incremental operational cost was non-existent since no extra energy source was required for the motionless mixer.

In addition, the quality of the end product was greatly improved due to the increased purity of the batching process and the consistency of the colorant addition. All of the process improvements resulting from the addition of the Kenics static mixer contributed directly to the bottom line for this manufacturer.

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