Embodiments of the present invention relate to a filter apparatus and method, and more particularly to self-cleaning filters for removing relatively fine particulate material from a fluid stream.
Many fluid streams contain particulate matter, and it is often desirable to separate this particulate matter from the fluid stream. If not separated, the particulate matter may degrade product quality, efficiency, reduce performance, or even cause severe damage to components within the system.
Many types of filters have been designed for the purpose of removing particulate matter from fluid streams. Such filters have typically included a filter element designed to screen the particulate material. However, the particulate material often becomes entrapped in the filter element. As the quantity of particulate material, often referred to as filter cake, collects on the filter element, the pressure drop that occurs across the filter element increases. A pressure drop across the filter element of sufficient magnitude can significantly reduce fluid flow at which point the filter element must be periodically cleaned, or replaced with a new filter. Often, this is done manually by removing the filter element and cleaning the filter before reinstalling it back in the system. Manual cleaning is a time consuming operation as it involves significant disassembly and re-assembly. It also requires taking the process off line. Manual cleaning can also be a dirty one, with the potential for dislodging hazardous, or toxic, particles that can be inhaled or ingested. It can also be a dangerous operation, if the fluid is flammable or toxic.
To minimize manual operations, filters have been designed to accomplish continuous self-cleaning. However, filters that use back pulsing to dislodge materials or blades to scrape off caked particulate are often very intricate and costly mechanisms. Some filters are cleaned with sprayed fluids, such as water or air to remove the particulates often resulting in the need to dispose of a large fluid volume of contaminated, hazardous matter. Moreover, many current approaches require extreme pressures or forces to dislodge caked particulate from the filter.
What is needed are filter systems and methods that do not generate unwanted hazardous matter, and that able to remove particulates from a fluid stream in a way that is relatively simple, reliable, flexible, easy to manufacture, that supports long-term operation, is easy to maintain, and is self-cleaning. Relatedly, there continues to be a need for filters that can be operated as one of a plurality of filters, and that can operate either independently of other filters or in concert with other filters. Embodiments of the present invention address at least some of these needs.