Process Control Improvement: On-Line Detection of Black Spots and Foreign Bodies

Sugar industry has always been trying to improve and guarantee quality of its product for its customers. In the crystallization process of white sugar, there are risks of contamination by foreign particles, and also visual pollution due to the presence of coloured sugar crystals.

3 zones can be monitored:

• the pan before graining
• the diverted off-spec in a container after the screening installation
• the dryer outlet before the bagging station or the silo

1) Syrup analysis is one of the first detectable pollution in the crystallization process

Especially where the stainless steel pipes and tanks are not used, some particles of rust can be found. The on-line analyzer Crystobserver® by ITECA SOCADEI can monitor the crystallization process and automatically trigger alarms for the production team.

Figure 1: Contaminants in the syrup, detected by the pan microscope CrystObserver®

2) The qualitative analysis of the diverted off specs and lumps

allows the traceability of the produced sugar quality. It helps to set correlations between the collected contaminants and actions in the process such as works and commissioning of new machines.

Figure 2: Contaminants collected during several production campaigns: n°1 white paint, n°2 paper, n°3 wood, n°4 resin, n°5 conveyor belt, n°6 non magnetic steel, n°7 seals, n°8 fibers, n°9 grey fibers, n°10 conglomerates

BacObserver®: at-line analyser
Figure 3: The BacObserver® has been developed by ITECA Socadei to analyze at-line images of sugar after the screening installation.

From data and images, the software triggers alarm to the DCS. It warns immediately the operator: the origin of these particles must be identified before restarting the monitoring mode.

is the most critical location, the last quality control before the storage silo. Several types of contaminants can be detected: charred sugar, ferric and non-ferric particles, and brown crystals colored by the massecuite mainly during the centrifugation.

Figure 4: Black and brown spots from the same production line

In response to a growing need, ITECA Socadei has developed the SpotObserver®. A high resolution camera continuously scans the sugar conveyor at high speed. Powerful and reliable LED lights illuminate the measurement area for the best image analysis. Designed for explosive atmosphere ATEX22

Figure 5: SpotObserver® : on-line analyser

A customized software analyzes 100% of the running production. It triggers alarms and activates, if it does exist, a diverting system. No-compromise quality: no contamination of the silo or bagging station.

Real-time production inspection is becoming the rule. The enhancing performance of image analysis combined to new and new reliable lighting technologies make it possible. The way to higher traceability, higher quality and better process control,
in the Sugar Industry since 1990
Exclusive agent in Thailand: 06-3045-5429