The internal and external pressure type of the kitchen water purifier

An ultrafiltration membrane is composed of hundreds to thousands of fine hollow fiber filaments, and the ultrafiltration membrane between the inner diameter of the hollow fiber membrane is generally called capillary ultrafiltration membrane, and the capillary ultrafiltration membrane is not easy to be blocked by large particulate matter due to its large inner diameter.

According to the different water inlet methods, ultrafiltration membranes are divided into two types: internal pressure type and external pressure type

1. Internal pressure type:

That is, the stock solution first enters the hollow filament, driven by the pressure difference, and penetrates through the hollow fiber from the inside to the outside along the radial direction to become the permeable liquid, and the concentrate stays inside the hollow filament and flows out from the other end, and its flow direction is shown in the figure below

2. External pressure type:

The hollow fiber ultrafiltration membrane is the stock solution that penetrates through the hollow fiber from the outside to the inside along the radial direction through the pressure difference to become the permeable liquid, and the trapped material is collected on the outside of the hollow filament, and its flow direction is shown in the figure

Performance characterization of ultrafiltration membranes.

The performance of ultrafiltration membrane usually refers to the physicochemical performance and separation permeability of the membrane, the physicochemical performance mainly includes the mechanical strength of the membrane, chemical resistance, heat resistance temperature range and applicable PH value range, etc., and the separation permeability performance mainly refers to the water flux, cleavage molecular weight and retention rate of the membrane.