1. Ceramic cross-flow filtration removes Particulate Material from any solution. Solution can be water or non-water based. Ceramic Micro-Filtration is not impacted by Total Dissolved Solids content of the solution so very high conductance water, or chemical solutions, can be processed using ceramic cross-flow filtration. Based upon the desired project goals, ceramic membrane tubes can be selected with which a precise range of particulate material can be removed from a solution. Specific ceramic membrane tubes are available to filter particles from as small as 0.01 microns (nano-particles) up to 5 microns in size. Average flux rates through the ceramic filters are dependent upon solids loading and viscosity of the liquid suspension. It is wise to perform pilot scale performance parameter testing on any material being considered for ceramic filtration prior to beginning system engineering design work.
2. Ceramic cross-flow filtration is especially applicable for concentrating solids in a volume of solution while simultaneously extracting a solids-free “permeate” stream. This can be useful when the solids are either valuable and it is desired to concentrate and collect these solids or when the solids loading is very high and collecting the solids on cartridge media is costly or interrupts processing frequently. Ceramic cross-flow filtration can typically be operated continuously with periodic “back-pulse” cycles to clean material from the ceramic membrane surface. Little or no back-pulsing is required for many types of suspended solids that tend not to adhere to the ceramic membrane surfaces when the system is operated in a high velocity cross-flow mode. Such operation is typical in precious metals suspension concentration, abrasive parts cleaning, chemical solution and beverage clarification, etc.
3. Ceramic cross-flow filtration can be operated in a dead-end filtration mode, (similar to how cartridge filters are operated) when there is a relatively small amount of solid material to remove in relation to the volume of solution being processed. In this operating mode, a very infrequent back-pulse cycle may be used to automatically clean the solids to waste. This type of operation eliminates the need for, and cost of, replaceable cartridge filters while providing superior particulate remove efficiency and effectiveness. Such operation is typically used for pretreatment of reverse osmosis membrane feed water and for bacteria removal in municipal water production. It is important to note that consideration needs to allow for disposal of the liquid waste stream generated in order to expel the particulate form the filtered solution stream. Typically, the waste stream can be less than 5% of the total processed flow when using a high efficiency ceramic cross-flow filter system.
4. Ceramic filter elements are extremely robust and can withstand high differential pressure operation, high fluid temperatures, acidic or basic chemicals, volatile liquids, oily, soapy, abrasive or fibrous suspensions. Consideration of the size and nature of the particulate material being filtered when selecting the flow passage capillary diameter of the ceramic filter tube in order to minimize element plugging in severe applications.
5. It is recommended to perform Ceramic Cross-Flow Filtration efficacy trials on any suspension, solution or slurry in order to develop system designs for the most advantageous removal rating and operating mode for these systems – especially when treating unique materials.