Bag Filters
Spray drying plants are equipped with powder separators to collect the powder entrained in the exhaust air. There are several different types of separators including cyclones wet scrubbers and bag filters.

Stricter requirements to reduce powder emission - now down to 10 mg/Nm³ of process air - and the potential for a higher yield by collecting more of the powder led to the development of the GEA Niro SANICIP™ CIP-able bag filter

GEA Niro SANICIP™ CIP-able bag filter
The GEA Niro SANICIP™ bag filter is a reverse jet type filter, designed in accordance with the strictest sanitary requirements given by the leading international agencies in EU and USA.

Working Principle
The exhaust air containing powder particles is passed through the GEA Niro SANICIP™ filter. It consists of a cylindrical bag housing with a tangential or direct air inlet, clean air plenum on top, and a conical bottom with fluidized powder discharge. During operation, the product collected on the outside of the filter material is blown off by a compressed air jet stream from the inside of each bag by means of a specially designed reverse jet air nozzle (patented) positioned above the bag.

The working principle results in a very even discharge of powder. The frequency and duration of the cleaning sequence can be adjusted to suit actual running conditions. The result is a low pressure drop across the filter, i.e. reduced energy consumption and noise emission.

All the fines discharged from the bag filter are returned to the process. This means that virtually no powder is lost as waste, but sold as first-class product. Retrofits of old plants equipped with cyclones and traditional bag filters or wet scrubbers can now be done by replacing the old exhaust system by a GEA Niro SANICIP™ bag filter.

Full utilization of energy recuberation is now possible if a heat recovery system is installed after the SANICIP™ bag filter. As there are practically no powder particles left in the exhaust air the heat recovery system can be designed so that the air with the moisture - on vapor form - can be cooled to below the condensation temperature and all the entrained energy can be reserved and reutilized.

 Benefits:

  • Sanitary design - all areas of the bag filter are CIP-cleaned.
  • Removable top covers - easy access to bags and cages.
  • Easy maintenance - no moving parts.
  • Tangential or direct (radial) air inlet – for optimization of plant layout 
  • Low pressure drop – reduces power consumption and noise emission.  
  • Up to 7 m bags are available – for reduced footprint.
  • Fluidized bottom – even difficult high fat powders can be discharged from the filter.
  • Heated cone - to avoid powder build-up and bacteria growth.