RU2124922C1 - Method of cleaning of filtering partitions of solid impurities - Google Patents

Abstract

FIELD: liquid filtration. SUBSTANCE: method consists in the fact that partition is cleaned by motion of clarified liquid in the following sequence: rest, flow in the reverse direction at different velocities of direct and reverse flow of liquid. EFFECT: effective cleaning of filtering partition at continuous filtration. 1 dwg

Description

 The invention relates to techniques for cleaning filter baffles when filtering liquids and can be used in the oil and fat industry for the primary treatment of vegetable oils, as well as in the chemical, paper and other industries for the purification of river, technical and recycled water.

 Known methods of cleaning filter baffles under the action of centrifugal forces that occur when the filter rotates, blowing the filter baffles with air or steam in the direction opposite to the movement of the filtered fluid, giving the filter baffle oscillatory movements, etc. [Shcherbakov V.G. The technology of obtaining vegetable oils. - M .: Kolos, 1992].

 Closest to the invention in technical essence is the regeneration of filters by imparting oscillatory motions to a liquid with constant frequency and amplitude [USSR Author's Certificate N 806070, cl. B 01 D 35/20].

 Cleaning the filters in this way is not effective enough, since the oscillation of the plate according to the symmetric, two-period law causes oscillatory movements of solid particles of the sediment near the filter baffle according to the same law, which leads to the possibility of the same sediment particle repeatedly falling onto the filter baffle, especially when it located vertically. In addition, when the vibrating head moves in the direction of the filtering partition, the filtering process is suspended, which reduces the filter performance.

 To increase the efficiency of cleaning the filtering septum and the filtration performance, cleaning the filtering septum is carried out by oscillating the liquid by means of a cam vibrator with a predetermined law of motion: upright - forward stroke - upright - reverse stroke. The cam profile provides various speeds and intervals of the forward (working) and reverse vibrations of the vibrator: with a forward stroke, the speed is higher and the interval is shorter than with the reverse.

 The method is as follows. The initial contaminated liquid without preliminary sludge flows to the filtering partition. Particles suspended in the initial liquid begin to settle on the mesh cells of the filtering septum, forming a “lining” of the filtering layer. As the “lining” grows, its resistance increases due to the fact that the smallest particles contained in the liquid supplied over the “lining” are placed in the voids between the particles of the “lining”, as a result, the filtration performance decreases.

 To clean the filter baffle, the cam mechanism is turned on and the vibrator vibrates according to a two-period, asymmetric, inhomogeneous law of motion. Since the vibrator’s speed is high and the interval is small, the clarified liquid, passing at a high speed through the filtering baffle, tears the sediment from it, which, under the influence of gravitational forces, begins to settle to the bottom of the filter. This process is facilitated by the upright period of the vibrator dwell. The vibrator’s return stroke, caused by the action of the spring, occurs at a significantly lower speed and a longer interval, which prevents the suspension particles from re-settling on the cells of the filtering partition and compacting.

 An example of the proposed method is illustrated in the drawing.

 The original contaminated liquid without preliminary sludge through the pipe 1 enters the housing 2, passes through the filter baffle 3 from the fine mesh into the chamber 4 of the clarified liquid and is discharged from the filter through the pipe 5. As the sediment accumulates on the filter baffle, the cam drive 6 is turned on (not shown shown), which results in a reciprocating movement of the vibrator, consisting of a rigidly connected rod 7 with the plate 8 and the spring 9. The law of motion of the vibrator set by the cam: standing - forward running - standing - arr pleasing move with different velocities and varying direct (working) and reverse strokes provides effective cleaning of the filter walls in a continuous fluid treatment. Suspension particles settled to the bottom enter the device 10, through which they are removed from the housing.

Claims (1)

 A method for cleaning filter baffles from solid mechanical impurities by vibrations of a clarified liquid, characterized in that the liquid is carried out in the sequence: rest - flow in the forward direction - rest - flow in the opposite direction at different speeds of the forward and backward fluid flows.