Low temperature plasma equipment is widely use

Low temperature plasma equipment is widely use:

The plasma technology is simple, the adsorption method should consider the regular replacement of adsorbent, desorption may cause secondary pollution; Combustion requires very high operating temperatures; In the combined catalysis method, the catalyst is selective, some conditions (such as too high temperature) will cause the catalyst deactivation, photocatalysis can only use ultraviolet light, etc. The biological method must strictly control the pH value, temperature and humidity and other conditions, in order to suit the growth of microorganisms.

However, the low-temperature plasma technology can better overcome the shortcomings of the above technologies. The reaction conditions are normal temperature and pressure, the reactor structure is simple, and the mixed pollutants can be eliminated at the same time (some cases have synergistic effects), and secondary pollution will not be generated, etc. In terms of economic feasibility, low temperature plasma reaction device itself to a single compact system structure, in terms of operating cost, microscopic, due to the discharge process improve the electron temperature and ion temperature only basic remains the same, this reaction system is to keep the low temperature, so not only high energy utilization, and make the equipment maintenance cost is low.

Low temperature plasma technology has a wide range of applications, and gas velocity and concentration are two very important factors for the application of gas pollutant treatment technology. Biofiltration and combustion can be applied in high concentrations but are limited by the flow rate of the gas. Electron beam irradiation technology has only a very narrow range of gas velocity. Low temperature plasma technology has a wide range of applications for gas velocity and concentration, and its wide application is self-evident.

Low temperature plasma technology has significant advantages in the treatment of gaseous pollutants. The basic principle is to produce high-energy electrons under the acceleration of electric field. When the average energy of electrons exceeds the chemical bond energy of the target molecule, the molecular bond will break, so as to eliminate gaseous pollutants. In the 1980s, the high-voltage pulsed corona discharge method proposed by Professor S. Masuda of The University of Tokyo in Japan is a simple and effective method to obtain low-temperature plasma at room temperature and pressure. It has become the current research frontier and is being used more and more in the treatment of gaseous pollutants.

Mechanism of pollutant removal by low-temperature plasma:

In the process of plasma chemical reaction, the energy transfer in the reaction process of plasma chemical energy is roughly as follows:

(1) Electric field + electron → high energy electron

(2) High-energy electron + molecule (or atom)→(excited atom, excited group, free group) active group

(3) Active group + molecule (atom)→ products + heat

(4) Active group + active group → products + heat

As can be seen from the above process, electrons first obtain energy from electric field, and transfer energy to molecules or atoms by excitation or ionization. Molecules or atoms that obtain energy are excited, while some molecules are ionized, thus becoming active groups. After that, the stable products and heat are generated after the collision between these active groups and molecules or atoms or between the active groups and the active groups. In addition, high-energy electrons can be captured by substances with strong electron affinity such as halogens and oxygen and become negative ions. This kind of anion has good chemical activity and plays an important role in chemical reaction.

Principle of removal of pollutants by low-temperature plasma equipment:

Low temperature plasma technology to deal with the principle of pollutant is: under the action of applied electric field, the discharge of a large number of medium and electron bombardment of pollutants, and the ionization and dissociation and excitation, and then raises a series of complicated physical and chemical reaction, make complicated molecules pollutants into simple small molecule safe material, or make the poisonous and harmful substances into harmless non-toxic or low toxic less harmful material, hence leading to the degradation of pollutants removal. Since the average energy of electrons generated after ionization is at 10eV, the reaction conditions can be properly controlled to realize the chemical reactions that are difficult to realize or slow in general conditions and become very fast. As a new and high technology with potential advantages in the field of environmental pollution treatment, plasma has been highly concerned by the related disciplines at home and abroad.

Low-temperature plasma equipment can be used in the electronic industry, such as mobile phone case printing, coating, dispensing and other pre-treatment, mobile phone screen surface treatment; Surface cleaning of aerospace electrical connectors in the defense industry; General industry screen printing, transfer pre - printing treatment, etc.

Through the treatment, can make plastic has the barrier property, the metal has the anti-corrosion ability, or the glass has the anti-dirt ability. After the material treatment, coating or printing quality is higher, more stable, longer durability. Low temperature plasma equipment, users can be specific processing process, become efficient, economic, environmental protection of advanced processing technology.