The bag filter installed on the Lime Hydrator System is mainly to filter the dusted steam generated from the lime hydration process, which has high moisture content and may condensate on the filter bags along with the fine particles of hydrated lime it carries. Once this happens, it will soon cause the failure of the filter bags and the whole lime hydration plant has to be shut down. To prevent this from happening, there are a few precautions that could be taken.
1. Bag filter system should be designed with proper number of filter bags and draft fan, so it could keep the average moisture level in the airflow below the dew point.
2. Bag filter for the lime hydration system should always be installed directly above the lime hydrator, not independently connected via pipes, so the air temperature drop from the hydrator to bag filter will be minimized to prevent condensation from happening.
3. Keep the bag filter running for a longer time after the lime hydration system is shut down till the temperature in the lime hydrator drop to certain point. If the bag filter is shut down too early, the incomplete hydration reaction in the hydrators will continue to generate steam that may saturate the air and cause condensation on the filter bags.
4. Install an insulation layer on the outside of bag filter to prevent temperature drop, and/or increase reaction temperature in the lime hydrator.
5. In case of an old lime hydration plant, nothing can be done on its structure. Additional heating of the steam may be considered.
6. At last, always choose suitable type of filter fabric for the the filter bags.
Please contact us if you need a new Lime Hydration Plant, our hydration system is designed with an optimized bag filter system that never clogs prematurelly.
