RU2122899C1 - Blade centrifuge - Google Patents

Abstract

FIELD: equipment for separation of suspensions in centrifugal field in various branches of industry. SUBSTANCE: blade centrifuge has a body, filtrate collector, distribution device and rotor with filtering blades. Distribution device is made as an inverted truncated cone with a definite angle of inclination of generating surface to horizontal plane. The truncated cone has slots used to feed the suspension to be separated to filtering blades. The width of blades smoothly increases in height of blades. Each blade is furnished with a clamp plate with one unfastened end, and having, a height equal to the blade. The other end of the clamp plate is attached to supporting tube of the previous blade for turning around it. EFFECT: uniform distribution of suspension to initial blade sections. 2 cl, 2 dwg

Description

 The invention relates to a device for separating suspensions in a centrifugal field, namely, paddle filter centrifuges, and can be used in agriculture, chemical, food and other industries.

 Known paddle centrifuge [1], including a housing, a filtrate collector, a switchgear and a rotor containing a cover, a bottom and filter blades located between them. The switchgear is made in the form of radially located and connected to the initial sections of the blades and the bottom of the rotor of the plates.

 The lateral ribs of the diametrically arranged plates are connected at the bottom of the rotor, and a gap is formed between them at the lid.

 A disadvantage of the known centrifuge is that the dispenser does not provide a uniform supply of slurry over the entire height of the filter blades, while an increased flow rate of the slurry enters the lower part of the blades, which leads to an increase in the moisture content of the precipitate obtained by centrifugation. In addition, the wear of the filter sieves of the blades in their lower part is increased. The result of the invention is to improve the quality of separation of the suspension by distributing them uniformly to the initial sections of the filter blades along the entire height of the rotor.

 This result is achieved in that the switchgear is made in the form of an inverted truncated cone with a certain angle of inclination to the horizontal plane, while slots for feeding the suspension are cut in the switchgear, the width of which gradually increases along the height of the device from the bottom to the rotor cover. Ensuring a uniform supply of suspension leads to the appearance of a constant thickness of sediment over the entire height of the blades, which allows for the intensification of the dewatering process to use pressure plates with an unsecured end and a height equal to the height of the previous blade with the possibility of rotation around it. The invention is illustrated in figure 1, which schematically shows a longitudinal section of a centrifuge, and fig. 2 is a section along AA of FIG. one.

 A centrifuge blade consists of a housing 1, a filtrate collector 2, a distributor in the form of an inverted truncated cone 4 and a rotor mounted on a vertical shaft 3, including a cover 7, a bottom 10 and filter blades 8 located between them, each of which consists of a housing 11, sieves 12 and a nozzle for drainage of the filtrate 9. Each blade is supported by a tube 15. To supply the suspension to the blades, slots 5 of variable width are cut in the lateral surface of the switchgear, the number of which is equal to the number of installed blades. Each blade is equipped with a pressure plate 13 with one loose end, its second end is fixed to the support tube 15 of the previous blade with the possibility of rotation around it.

The centrifuge operates as follows. The initial suspension through the pipe 6 enters the switchgear rotating with the rotor and, under the action of centrifugal force, is discarded to the walls of the switchgear. Further, the suspension through the slots 5 enters the inlet sections of the filter blades, evenly distributed over their entire height. When filtering the suspension through a sieve 12 of the blade, a sediment layer forms on the latter, moving to the periphery of the rotor, i.e. to the window for unloading sludge 14. To intensify the dewatering process, the sludge is pressed by a plate 13, which, under the action of centrifugal force, is deflected towards the filter sieve. Since the height of the plate is equal to the height of the sieve of the blade in _p , and the thickness of the sediment h _{OS is} constant in each cross section, the latter is uniformly pressed by the plate 13 along the entire height of the filter sieve.

где К_р - коэффициент, К_р = 0,8...0,9;
ω - угловая скорость вращения ротора;
r_в - радиус распределительного устройства на уровне крышки ротора;
g - ускорение свободного падения.Studies have shown that for a more uniform distribution of the suspension on the centrifuge blades, the angle of inclination of the cone of the switchgear to the horizontal plane should be equal

where K _p - coefficient, K _p = 0.8 ... 0.9;
ω is the angular velocity of rotation of the rotor;
r _in - the radius of the switchgear at the level of the rotor cover;
g is the acceleration of gravity.

The conical-shaped switchgear does not provide complete uniformity of the suspension supply to the blades due to the inertia of the flow. To achieve this, it is necessary that the entrance slots cut in the lateral surface of the cone expand smoothly along the height of the blade (rotor), for example, according to the linear law
δ = δ _n + K _in • z _p , (2)
where δ _n - the width of the slit at the level of the bottom of the rotor;
K _in - coefficient;
Z _p - coordinate, measured from the bottom of the rotor, 0≤Z _p ≤ in _p .

 Using the proposed paddle centrifuge in comparison with the prototype allows you to get a dehydrated precipitate of lower humidity and reduce the wear rate of the sieves of the blades.

Literature
1. Copyright certificate of the USSR N 1199270. M. Kl. B 04 B 3/00. L.I. Vysotsky and others.

 2. Paddle centrifuge. Bulletin of inventions N 47, 1985.

Claims (2)

1. Vane centrifuge, comprising a housing, a filtrate collector and a rotor installed in the housing, comprising a cover, a bottom, filter blades located between them on support tubes and a switchgear, characterized in that the latter is made in the form of an inverted truncated cone, the angle of inclination of the forming surface of which to the horizontal plane is equal

where K _p - coefficient, K _p = 0.8 - 0.9;
ω is the angular velocity of rotation of the rotor;
r _in - the radius of the switchgear at the level of the rotor cover;
g is the acceleration of gravity,
while the truncated cone has slots for receiving a suspension on the blades, the width of which gradually increases along the height of the blades.  2. The centrifuge according to claim 1, characterized in that each blade is provided with a pressure plate, one end of which is not fixed, and the second is mounted on the support tube of the previous blade with the possibility of rotation around it.

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