Commonly used Cleaning methods for filter elements

If you are considering the filter from HYDAC Process technology, choose the following factors:

·         Inline filters in single and duplex versions

·         Strainer filters in single and duplex types

·         High pressure filters in stainless steel

·         Automatic backflushing filters

·         Filter systems with combinations of wide range of components

There are main design principles that should be taken into consideration:

a.       Material resistance to the medium, for which variety of materials and solutions are chosen.

b.      Flow rate

c.       Pressure

d.      Pressure drop

e.      Temperature

f.        Connection sizes

g.       Filtration rating

h.      Economic factors

The core of every filter is the filter element. It provides solutions for the varied filtration applications, diverse filter materialsof sintered wire mesh and element models are chosen. Many filter materials can be cleaned, hence preventing the significant costs of purchase and storage.

Filtration Process

Nominal filtration rate: The filtration ratings are based on a factory standard filter test, that is conducted by introducing a large magnitude of dust, in the beginning of the filter test and after separating the contamination particles over 60 minutes. The test filter retains 90 to 95% of all particles larger than the specific filtration rating.

Absolute retention rate: The filtration ratings are found by the multi-pass test performed on the test rig. At nominal 99% of particles larger than the specific filtration rating should be helped and this up to the maximum permissible differential pressure across the filter element.

Cleaning Filter elements

The filter elements should be divided into cleanable and noncleanable filter materials. The selection of filter materials should be made as per economic, ecological and system specific factor. For process filtration, a cleanable filter material is often used.

The selection of cleaning methods is based basically on the type of contamination and filter material. For a better cleaning effect, specific processes can be combined together. It ensures that the cleaning parameters and selected solvents do not corrode the filter material.

Not all types of cleaning can be performed by the operator. Specialized firms can perform this by using cleaning elements. Common cleaning methods used are:

High pressure cleaning: Fit for cleaning coarse and loose particles manually and automatically with high pressure jets.

Ultrasound cleaning: Cleaning filter elements in ultrasound bath works by breaking down and flushing the contamination particles that is embedded in the element. The ultrasound bath is conducted in the range of 20 to 40 kHz using water and surfactant additive. Or specific solvents can be used.

Scalding in solvents: Scalding of the filter elements used where the elements are kept in a closed circuit, acting as a rinsing machine. The system operates with solvents at the elevated temperatures.

Scalding of the filter elements used where the elements are kept in a closed circuit, acting as a rinsing machine. The system operates with solvents at the elevated temperatures.

Pyrolysis: This cleaning method is based on the degradation of organic material that has accumulated on the element. The organic material is vaporized at high temperatures in a low oxygen condition.