Compared to a conventional screw heat exchanger the new design, a 2:1 screw pitch ratio — and a corresponding 1:2 speed ratio between the two shafts —  provides self-cleaning operation, aided by narrow gaps between the screw flights. (Picture: Köllemann)
Modified Screw Heat Exchanger

Screw Heat Exchanger Keeping Itself Clean

For many industries that produce, process, or handle bulk solids, the screw heat exchanger is a well-known piece of equipment for heating, drying and cooling. With the same working principle as a conventional screw conveyor, however, most screw heat exchangers rely on the flowability of the bulk solid for good mixing and to keep their heat transfer surfaces clean. As a result, these standard screw heat exchangers cannot be used for sticky, pasty or adhesive materials or slurries.

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The EE871 CO2 sensor is highly resistant to hydrogen peroxide. (E+E Elektronik)
Sensors

Measuring Carbon Dioxide with High Accuracy

The digital EE871 probe from E+E Elektronik measures CO2 concentrations up to 50,000 ppm. The compact probe is now available with a special filter cap which ensures high accuracy and long-term stability in H2O2 contaminated environment such as the pharmaceutical and biotech industries.

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