Confectionery production factories all over the world need to dose flavors, aromas and colors with a high level of accuracy and reproducibility.

Production machines require compact modules for dosing additives for measuring and controlling. Mounting positions directly at the dosing spot gives best results. Low dead volumes between sensor and valve are essential to be able to dose the exact amount. Trends like using natural ingredients for aromas, flavors and colors for confectionery products especially require higher accuracy and reproducibility for the measuring and controlling devices because these natural ingredients have a larger diversity of product properties.

Bronkhorst Cori-Tech provides compact solutions of Coriolis controllers with CORI-FILL® technology. This includes integrated totalizers for batch dosing using directly controlled shut-off valves, proportional valves, or liquid pumps.

Each Compact Fluid Dosing Assembly consists of a Coriolis Mass Flow Meter of the mini CORI-FLOW® or CORI-FLOW® series and a valve or a (gear) pump. The onboard PID-controller of the flow meter will be optimized for controlling the valve or the (gear) pump and enables an immediate start of dosage after connecting power and fluid accessories.

Using the integrated CORI-FILL® technology, the Coriolis meter's totalizer is capable of highly accurate batch dosage. It also ensures the actuator will react as soon as the batch has been reached. Normally several components would be needed to achieve this:

- flow meter

- valve/pump

- batch counting module/PLC

- software handling these items

CORI-FILL® offers all batch dosing functionality in one component, in one assembly and from one supplier, without the need of complex programming of additional hardware.

All CORI-FLOW® instruments are capable of operating with both +24Vdc electric shut off valves and pneumatic valves. CORI-FILL® technology includes an automatic overrun correction on batch dosing. After just a few doses the accuracy will be optimized. Physical delays and pressure disturbances which might cause under- or over-runs will be automatically compensated.

Thermal mass flow instruments use temperature, as their name suggests, in calculating mass flow. There are, however, several ways to use temperature to calculate mass flow.

Thermal mass flow instruments that use a bypass (capillary bypass, bypass sensor) are what most people have in mind when they think of thermal mass flow instruments. In these instruments power is applied to heat the sensor tube and then the temperature of the tube is measured at two points. With no flow the temperature differential between the two points will be zero. As flow increases the temperature at the first measuring point will decrease as fluid carries away heat, and the temperature at the second measuring point will increase as the fluid carries heat to it. More flow results in a greater temperature differential. The temperature differential is directly related to mass flow.

Another technology used to measure mass flow is CTA (Constant Temperature Anemometer). In a CTA (through flow, straight tube) instrument there are two measurement "pins" inserted in to a straight tube flow path. The first "pin" both heats and measures the temperature of the fluid, and the second "pin" measures the temperature of the fluid. Again, as fluid flow increases the fluid will carry heat from the first measuring point to the second. In a CTA, however, the power is varied to keep the temperature between the two measuring points constant, and it is this power level that is used to calculate mass flow.

Each technology has its advantages and disadvantages which generally are application specific. A clean, dry gas where accuracy is as important as repeatability may be a better application for a bypass instrument like the Bronkhorst EL-FLOW. An application with a dirty or slightly moist gas, or where lower accuracy but high repeatability is required may be a better application for a CTA instrument like the M+W Mass-Stream™.