What Is The Difference Between Dead-End Filtration And Cross-Flow Filtration?
Ceramic membrane manufactured by JIUWU HI-TECH is used for liquids separation in a cross-flow filtration way, which is different from dead-end filtration. There are discussed in the following contents.
1. Dead End Filtration
1.1 Dead End Filtration Definition
Dead end filtration means the fluids flow is vertical to the filter surface, and the retained particles rapidly solidify on the surface of the filter to form a so-called filter cake. The pores of the filter are clogged by the filter cake, and the filtration performance is greatly reduced in a short period of time.
1.2 Dead End Filtration System
In the dead end filtration system, it only needs to overcome the membrane resistance. So, an ordinary laboratory vacuum pump or booster pump can provide enough energy to achieve the required flow rate of the microfiltration. However, with the increase of time, the accumulation of particles on the membrane surface also increases, and the filtration resistance decreases the membrane penetration rate. Therefore, the dead-end filtration is intermittent, and it is necessary to periodically stop and clean the contaminated layer on the membrane surface or replace the membrane.
1.3 Advantages of Dead End Filtration
With its own special advantages, the dead end filtration has been used most commonly for laboratory and medical filtration.
(1)The dead end filtration operation is simple and suitable for small-scale occasions;
(2)The dead end filtration has an advantage of high product recovery;
In addition, the dead end filtration is usually used for materials with a solid content of less than 0.1%.
2. Cross Flow Membrane Filtration
2.1 Cross Flow Filtration Definition
Cross-flow filtration means turbulence will happen on the surface of the membrane. Therefore, it allows the filtered material to form a filter cake on the filtering surface and keep the flow constant.
2.2 Cross Flow Filtration System
The cross flow filtration is a kind of tangential flow filtration, which has been used widely in industry around the globe. In the cross flow filtration system, the solution to be filtered is pushed through the pores of the filter membrane by pressure. Because the liquid flow rate is very fast, so the filter pores of the filter membrane will not be blocked. The pore size of the filter membrane determines whether the nature of the filter membrane is microfiltration or ultrafiltration.
2.3 Advantages of Cross Flow Membrane Filtration
Compared with the dead end filtration, the cross flow filtration system has its own special advantages as follows:
(1)There is no need to add filter aid;
(2)It has simple and compact system structure;
(3)It is reusable after backwashing;
(4)The hollow fiber mold stack can be replaced to produce different products;
(5)It is easy to operate.
In conclusion, cross flow can remove build up from the surface of the membrane. So, the permeate flux does not drop as fast when compared to dead end filtration. Cross flow technology also provides the benefit of an improved membrane lifespan by helping to prevent irreversible fouling.
JIUWU Membrane Products
- November 1, 2018Membrane fouling is a major obstacle to wide spread application of the membrane. It is the phenomenon whereby the membrane permeated flux decreases and the transmembrane pressure (TMP) rise with the p...view
- December 27, 2018Ceramic membrane needs to be used and operated in normal operating procedures. The following conditions and chemicals of operation are absolutely not allowed, because it may destroy or damage ceramic ...view
- December 27, 2018A continuous process, easily automated; The exclusively physical separation that does not alter the products ;A closed system that eliminates contamination risks ;Applicable to many industrial process...view
- December 27, 2018From the perspective of microstructure, the inorganic ceramic membrane has two structures: "symmetric ceramic membrane" and "asymmetric ceramic membrane". Since asymmetric ceramic membrane has better ...view
- December 27, 2018Yes, ceramic membranes can be heat sterilized. But steam sterilization is a delicate procedure, which carries significant risks of damaging the system components often induced by the difficulty to con...view
- December 27, 2018Yes, it is. Ceramic membrane is a kind of Cross-flow filtration which is a continuous process in which the feed stream moves parallel to the membrane filtration surface and purified liquid passes thro...view