Multi-stage electrostatic spraying system and method

Abstract

The invention designs a multi-stage electrostatic spraying system and a method, belonging to the field of an electrostatic spraying technique, which comprises a first-stage electrostatic spraying device (1), a liquid storage device (4), a charge injection device (6), a lower-stage electrostatic spraying device arranged behind the first-stage electrostatic spraying device (1), and a Coulomb liquid drop separation and collection device, wherein the liquid storage device (4) and the charge injection device (6) are linked with the first-stage electrostatic spraying device (1); the lower-stage electrostatic spraying device at least comprises a second-stage electrostatic spraying device (3); the first-stage electrostatic spraying device (1) and the lower-stage electrostatic spraying device form N stages, and the N is a natural number larger or equal to 2; and at least one lower-stage electrostatic spraying device in the lower-stage electrostatic spraying device is provided with a temperature and pressure regulating device for carrying out the Coulomb splitting of electrostatic liquid so as to generate Coulomb liquid drops. The invention enhances the consistency of the size and the electric quantity of the liquid drops.

Description

technical field [0001] The invention relates to a multi-stage electrostatic spraying system and method, which is a general equipment and method for batch-producing Coulomb droplets with very good consistency and precise control by using the principle of Coulomb splitting, and belongs to the technical field of electrostatic spraying. Background technique [0002] Electrostatic spraying is a method of using electrostatic force to disperse liquid to produce fine droplet spray. Its basic physical principle can be explained from the leakage medium model proposed by G.Taylor and J.R.Melcher, etc., see Annual Review of Fluid Mechanics, 1969, 1, 111-146 of Electrohydrodynamics: A Review of the Role of Interfacial Shear Stresses and other literature. The method has been demonstrated in large biomolecular mass spectrometers (Fenn, J.B.; Mann, M.; Meng, C.K.; Wong, S.F.; Whitehouse, C.M. (2007). "Electrospray ionization for mass spectrometry of large biomolecules.". science 79 (4926):...

AI Technical Summary

Problems solved by technology

However, the known electrostatic spraying technology still has relatively obvious defects, mainly in two points: one is that the consistency of the droplets generated by the known technology is relatively poor, and the size and charge of the droplets are determined by the nature of the liquid itself. In addition, it is closely related to the initial spraying conditions of electrostatic spraying, such as the applied voltage, liquid flow rate, and the size of the spray tube used, so the size and charge of the generated droplets are easy to change with the change of external conditions, and such The random fluctuation factor in the change is very large, which also makes the further droplet selection very difficult

In addition, the side droplet (side droplet) generated by the lateral shear force and the Coulomb droplet (Coulomb droplet) generated by the Coulomb fission (Coulomb fission) will also be mixed with the original droplet produced by electrostatic spraying. Deteriorates the overall consistency of the droplet

It is known that the diameter of the droplets generated by the electrostatic spraying technology may usually vary in the range of millimeters to microns, and the ratio of the charge amount to the Rayleigh limit (Rayleigh limit, the maximum charge that a droplet with a given diameter can carry) ranges from close to It varies from 1 to a few ten-thousandths, and its statistical distribution cannot be precisely controlled

The second is limited to conditions such as the size of the spray tube. The diameter of the droplets generated by the known technology is generally above the order of ten microns. There is a large difference from the Rayleigh limit, which limits the further development of electrostatic spraying in finer applications such as nanotechnology

It is mainly due to the existence of these two technical defects that the known electrostatic spraying technology is still mainly limited to some technological and industrial applications that do not require high precision.

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