RU2166357C2 - Device for jet mixing of liquids - Google Patents

Abstract

FIELD: mixing technology. SUBSTANCE: proposed device includes mixing head with needle valves located in one plane, independent loops for delivery of components with working reservoirs, proportioning pumps, supply and discharge mains. Head for injection of component at high volumetric or weight content to mixing chamber is provided with several needle valves located an angle relative to one another. EFFECT: improved quality of mixing of two-component systems at reagent ratio considerably exceeding 1:1. 4 dwg

Description

 The invention relates to equipment for mixing reactive oligomeric and other liquid components in the preparation of compositions, in particular polyurethane, and can be used in chemical and other industries.

 An analogue of the design is a device for jet mixing chemically active liquids (US Pat. NR N 139144, N 244120, class B 01 J 4/02, B 01 F 5/00, 1987). The device consists of a mixing head and two separate component supply circuits. Each component supply circuit includes a working tank equipped with an agitator with a drive and a water jacket, powered by a thermostat, a metering pump, inlet and outlet pipelines. The mixing head contains two multi-way shutters that serve to switch the casting / circulating component flows.

 The disadvantages of this device include the high cost of flushing agents and materials after each casting cycle.

 As a prototype issued a device for the manufacture of products from monolithic and foam materials (US Pat. Germany N 3021095, CL B 29 D 27/02, 29 G 3/00, 29 V 1/06, 1983). The device consists of a mixing head with a cleaning plunger and separate circuits (two or more) of the supply of components. Each component supply circuit includes a working tank, a metering pump, a hydraulic needle valve, and inlet and outlet pipelines. Switching of the casting / circulation modes is carried out by needle valves.

Upon receipt of a two-component casting composition in the mixing head of this device, the jet of reagents are directed towards each other at an angle of 180 ^o . With a reagent ratio of 1: 1, the jets collide at the same distance from the nozzles of the corresponding valves, which is a necessary condition for an optimal mixing mode. At higher ratios, the flow core shifts from the axis of the mixing chamber, which impairs the quality of mixing due to increased friction on the chamber wall. The disadvantage of the design of the mixing head of this device is that the component with a large volume or weight content is supplied through the nozzle of one needle valve, and this does not provide high-quality mixing of viscous reactive components with their ratios significantly exceeding 1: 1.

 The technical task is to improve the quality of mixing two-component systems with ratios of reagents significantly exceeding 1: 1. Improving the mixing efficiency in the device is achieved by dividing the component stream with a large volume or weight content into several parallel flows and introducing into the mixing head the corresponding number of needle valves per line of this component. Needle valves that feed components into the mixing chamber are located in the same plane at an angle to each other.

 The proposed device allows to achieve high quality mixing of two-component systems with ratios of reagents significantly exceeding 1: 1. On the same device, it is possible to obtain compositions with ratios of components close to 1: 1.

 In FIG. 1 shows a diagram of a device with dividing a stream of a larger volume (weight) content into three parts; in FIG. 2 shows a mixing head, cross section; in FIG. 3 is a section AA in FIG. 2 (the left halves of the drawings correspond to the casting mode, the right halves correspond to the circulation mode); in FIG. 4 is a section BB in FIG. 2.

 The scheme of the mixing device with the separation of the flow into three parts contains two independent component supply circuits. Structurally, the design of the heads is possible with the splitting of the component stream with a high flow rate into four, five or more parallel flows.

 The feed circuit of component A includes a working tank 1 (see Fig. 1), a metering pump 2, a supply line 3, a mixing head 4 with a needle valve 5 and a discharge line 6.

 The feed circuit of component B includes a working tank 7, a metering pump 8, a supply pipe 9, supply pipes 9.1, 9.2 and 9.3, a mixing head with needle valves 10.1, 10.2, 10.3, discharge pipes 11.1, 11.2 and 11.3 and a discharge pipe 11. The supply pipelines 9.1, 9.2, 9.3 contain shut-off valves 12.1, 12.2, 12.3, flow controllers 13.1, 13.2, 13.3 and flow meters 14.1, 14.2, 14.3. The discharge pipes 11.1, 11.2, 11.3 contain check valves 15.1, 15.2, 15.3.

 Management of the needle clan 5 is carried out from the pumping station 16 through the valve 17 and pipelines 18, 19.

 The needle valves 10.1, 10.2, 10.3 are controlled from the pump station 16 through the control valves 20.1, 20.2, 20.3 and pipelines 21.1, 21.2, 21.3, 22.1, 22.2, 22.3.

 The mixing head comprises a mixing chamber 23 with a cleaning rod having a hydraulic actuator (not shown in FIG. 1).

 In the circulation mode, the electromagnets of the hydraulic valves 17, 20.1, 20.2, 20.3 are turned on, oil from the pumping station through pipelines 19, 22.1, 22.2, 22.3 is supplied to the valves 5, 10.1, 10.2, 10.3 and closes them. Component A from tank 1 is pumped by line 2 to line 5 to valve 5 and returned through line 6 to the tank. Component B from tank 7 is supplied by pump 8 through line 9, branches into three streams, and flows through pipelines 9.1, 9.2, 9.3 to valves 10.1, 10.2, 10.3. Return to the tank via pipelines 11.1, 11.2, 11.3 and line 11.

 When casting, the electromagnets of the hydraulic valves 17, 20.1, 20.2, 20.3 are turned off, the oil is supplied through the pipeline 18, 21.1, 21.2, 21.3 to the valves 5, 10.1, 10.2, 10.3 and opens them. Component A from tank 1 is fed through line 3 to valve 5 and injected through the nozzle into the mixing chamber 23. Component B from tank 7 is fed through line 9, branches into three streams and flows through valves 9.1, 9.2, 9.3 to valves 10.1, 10.2, 10.3; through the nozzles of these valves, injection is made into the mixing chamber.

 The branched flows of component B are regulated by the flow regulators 13.1, 13.2, 13.3 in the circulation mode. Control over the adjustment is carried out by flow meters 14.1, 14.2, 14.3.

If necessary, component B can be injected through one or two needle valves. If, for example, it is necessary to carry out the jet mixing of components A and B according to the traditional pattern (the jets of components are directed towards each other at an angle of 180 ^o ), then it is necessary to close valves 12.1, 12.3 and needle valves 10.1, 10.3. In the circulation mode, component B from the tank 7 is fed through the line 9, the pipe 9.2 to the valve 10.2; the return to the tank is carried out through the pipe 11.2 and line 11. The non-return valves 15.1 and 15.3 prevent component B from getting to the needle valves 10.1 and 10.3 through the pipes 11.1 and 11.3.

 The mixing head (Fig. 2, 3) contains a housing 4, a mixing chamber 23 with a cleaning rod 24, a needle valve 5 of component A with a supply 25 and a discharge channel 16, three needle valves 10.1, 10.2, 10.3 of component B with a supply 27.1, 27.2, 27.3 and channels 28.1, 28.2, 28.3. The rod 24 is placed in the hydraulic cylinder 29.

Valves 5, 10.1, 10.2, 10.3 are located in the same plane at an angle of 90 ^{o to} each other (Fig. 4), have the same design and function the same.

 Valve 5 feeds component A either into the mixing chamber or back into the container. When component A is circulating, the needle 30 of the valve 5 overlaps the nozzle 31 and connects the channels 25 and 26 (the valve is closed). When casting component A, the needle 30 overlaps the outlet channel 26 and opens the entrance to the nozzle 31 (valve open). Component flow control is carried out by a replaceable nozzle with a calibrated outlet.

 The device operates as follows.

 In casting mode, the treatment rod 24 of the hydraulic cylinder 29 is in the upper position. Valves 5, 10.1, 10.2, 10.3 are open. The liquid components under pressure through the nozzles of the needle valves enter the mixing chamber, where they are intensively mixed by the impact of the jets. The finished mixture goes to the next process step.

 In the circulation mode, the valves are closed, the components begin to circulate along the corresponding circuits. The cleaning rod 24 moves down, blocking the nozzle and removing the rest of the mixture from the mixing chamber.

 By the beginning of the next mixing cycle, the stem rises, the valves open.

Claims (1)

 A device for jet mixing liquids, comprising a mixing head with needle valves that are located in the same plane, independent component supply circuits, including working tanks, metering pumps, supply and discharge lines, characterized in that in the head for injection into the mixing chamber of the component with large volumetric or weight contents, several needle valves are provided, arranged at an angle to each other.

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