Process and apparatus for degassing and filtering liquids
AssigneeE. I. Du Pont de Nemours and Company
InventorDac-Vong Do
Life of this patent
Estimating the term…
Abstract
In a process for degassing and filtering liquids, particularly coating emulsions, a feed stream (F) is subdivided into a process stream (N), which is fed continuously to a process use through a main filter (16), and a recycled fractional stream. The fractional stream (T) is used to backflush successive sections of the main filter (16) and in turn is filtered through a supplementary filter (21, 22). In the apparatus for the process, a backflushing device (17) is associated with the main filter (16), the fractional stream (T) is used as a flushing means and the filter surface of the main filter (16) is cleaned progressively. Thus, a liquid with a continually constant grain size distribution, without gas bubbles and particles that cause defects, can be delivered continuously to the specific use.
Claims18
A process for degassing and filtering a liquid in which a feed stream of the liquid is subdivided into a process stream, which is fed continuously through a main filter to a specific use, and a fractional stream, which is withdrawn from an area of the main filter and recycled for reuse, characterized in that the fractional stream is used to backflush successive sections of the main filter and is itself filtered before rejoining the feed stream and in that the feed stream is at least partially degassed in a degassing vessel before it enters the main filter.
An apparatus for degassing and filtering a liquid comprising:
- a main filter unit;
- an inlet line for a feed stream connected to the main filter unit;
- a process line for a specific use stream;
- and a return line for a fractional stream which is withdrawn from an area of the main filter;
- characterized in that the main filter unit comprises a backflushing device, which uses the fractional stream as a flushing means and cleans progressively a filter surface of the main filter unit, and in that a supplementary filter is located in the return line and a degassing vessel is located in the inlet line.
Dependencies are inferred from the claim text.