Operating experience with the new cleaner product family InduraClean

Cleaners for the separation of heavy particles and dirt specks are installed in almost every paper mill in the approach flow system and/or stock preparation. Many plants are operated in the low stock consistency range with high differential pressures. Therefore, cleaners have a high share in the specific energy costs of these plant sections. Due to the process, the cleaner rejects of older plants often unnecessarily lose a lot of pulp.

In this presentation, the challenges typically encountered in the operation of cleaner systems will be addressed. Possible solutions, which have been implemented in the new product family, will be presented. One example is how blockages can be avoided by preventing deposits in the distribution pipes.

The focus of the presentation will be on the system results of the completely newly developed IDC-4F and the IDC-4Q. With these, it has been possible to advance the technology in this area by a significant step.

The InduraClean IDC-4 combines 4 small diameter hydrocyclones. Slim cleaner cones generate a higher centrifugal force, resulting in better separation efficiency. The challenge is to make the feed distribution and the merging in the reject and accept sections operationally reliable. The benchmark for this is the HCL5 EcoMizer Cleaner, which has been successfully setting standards for years, even at high stock consistencies.

A design was found that can be operated with a significantly reduced pressure drop at the same flow rate. This results in a significant reduction in operating costs due to low energy consumption. The high throughput per cleaner unit makes it possible to achieve significantly higher production with the same bank length compared to conventional solutions. The potential of the slim cones also makes it possible to significantly improve the cleaning performance of the cleaners.

All cleaners are equipped with the EcoMizer principle. With this principle, fibres are flushed back to the accepts in the reject discharge inside the cleaner. This counteracts local thickening, so that operational reliability increases at high stock consistencies and fibre loss is reduced at the same time.

Depending on the application, two cleaner variants are available:
The IDC-4F (FourFlow) was specially developed for large production capacities and is mainly used in the production of board and packaging papers. The InduraClean IDC-4Q (FourQuality), on the other hand, is particularly suitable for speciality papers and graphic paper grades, as the focus here is on the best possible cleaning efficiency and quality.

In England, for example, the IDC-4Q successfully separated tinsel and other "glitter" components from the suspension. To date, no other cleaner has been able to cope with this task. In Germany, during a rebuild project in an OCC plant, the energy costs were reduced by approx. 50% and at the same time the yield was significantly increased.

For paper manufacturers who want to invest in sustainability, the presentation will show possibilities to make significant steps forward in this field. High CO2 savings combined with a ROI that is often less than 2 years make a rebuild of existing cleaner plants or the investment in a new cleaner plant very attractive.