Filtration Process Optimization
The latest progress in process optimization:
Although the process filter has been improved, it does not completely change the structure of the equipment, and these improvements are rarely mechanical. The most obvious change is the type of filter material. Beginning with the earliest process filter, with the appearance of wire mesh, non-woven fabric and simple fiber felt, filtration efficiency and service life of filter material have been increased.
in addition to the improvement of filter performance brought by filter material, the energy efficiency of large filter equipment (such as belt filter and filter press) has also been improved. For example, the flatbed filter is the most commonly used purification equipment for the cooling system of machine tools. The basic structure changes little, but it becomes more and more compact. It also uses vacuum drive more often, not just gravity. The filter material is also rapidly changing from filter paper to synthetic material, such as spun-bonded fabric.
The filter press used in the final purification of liquid products in the beverage industry is still in its basic structure. Now, the main changes of press filter include: from a simple plate and frame structure to single module concave structure and diaphragm plate structure (often confused with the thin film). The diaphragm filter press uses an impermeable elastic diaphragm to squeeze the excess liquid out of the filter cake. In spite of the slow development, manufacturers still find room for improvement. For example, Larox recently launched a new Hoesch series filter press, the modular structure is adopted, with a set of standard options and a fast opening mode and a high standard seal.
The pressure vessel filter is usually multi-filter core structure with tubular filter or plate filter or horizontal strainer, and the drum filter is sealed in the pressure vessel. This is a very complicated design, especially to transport the separated solids through the shell.
The belt filter is a continuous running device for removing moisture from the pulp. After the initial dehydration process, the solid content in the suspended liquid can be converted from 1% to 35% of the filter cake. This filter is very energy-intensive, and the new design has made energy efficiency a major goal.
The intermittent vacuum filter is one of the most traditional models of the separation equipment and has little change. But the precision of the intermittent suction filters used in the chemical and pharmaceutical industries has improved. There is no change in the basic structure of blade type filter and plate filter, but the change of filter material helps improve the performance.
There are two types of continuous vacuum filter: rotary drum or disc filter and belt filter.