CN1654290A - Static electricity suspension technology - Google Patents

Abstract

The electrostatic suspending pneumatic transporting technology for bulk material includes: corona discharge to ionize conveying gas to generate great amount of gas ions carrying the same polarity charges; charging the material particles to be conveyed via diffusion and/or electric field; and setting suspending electrode and charging the suspending electrode with the same polarity charges to make the material particles suspended and conveyed by means of mutual repulsion of the charges in the same polarity. Applying the present invention can convey material in low speed or ultralow speed stably without contact to the conveying pipeline in low power consumption, less wear, no jamming and no limitation in distance.

Description

The electrostatic suspension Pneumatic Conveying Technology

1, affiliated technical field

The present invention is a kind of bulk material Pneumatic Conveying Technology.

2, background technology

Pneumatic Conveying Technology is to utilize gas as bearing medium in pipeline, and material from a delivery system that is transported to another place, is had that system and equipment are simple, transport efficiency is high, occupation of land is little, flexible arrangement is convenient, carry advantages such as airtight fully.

Existing Pneumatic Conveying Technology (can referring to monograph) as Chen Hongxun chief editor relevant strength conveying aspects such as " pipeline mass transport and engineering application ", material is different variation of the flow regime of delivery pipe contained inventory and material of material itself etc. in mainly with air-flow velocity, air-flow, in horizontal conveying pipe, be subjected to the influence of gravity, particle (material) trend is to the pipe bottom sediments.

Material is seen Fig. 1～shown in Figure 5 in the flow regime of delivery pipe (horizontal pipe).

When the very high and inventory of air-flow velocity in the pipeline seldom the time, material (particle) near rectangular distribution, and is complete suspended state and is transferred (seeing Fig. 1) in pipeline in air-flow.

Along with air-flow velocity reduces or inventory increases to some extent gradually, the air-flow thrust that acts on particle also reduces, and makes that particle speed is also corresponding to slow down; Add between particle and may bump that part larger particles trend was sunk near the pipe end, at this moment manage the distribution of substrate material and become close, but material still normally is transferred (seeing Fig. 2).

When air-flow velocity reduced again, the part particle became stratiform to be deposited on the pipe end, and at this moment air-flow and a part of particle pass through at its upper space, and on the surface of sedimentary deposit, the part particle is also slippage forward (seeing Fig. 3) under the effect of air-flow.

When air-flow velocity begins to be lower than floating velocity or inventory more for a long time; the particle that major part is bigger can lose suspending power and be stuck in the pipe end; in local location even because of solid accumulation formation " sand dune "; when crossing " sand dune " top, air communication speeds up because of passage is narrow; " sand dune " can be dispelled in a flash and destroy; when being deposited on the material at the pipe end and when stagnation and being blown away; at this moment frequence of exposure fluctuation of pressure phenomenon faster in the pipeline; if this moment, fluctuation to a certain degree appearred in air-flow velocity again, then conveying can present wild effect (seeing Fig. 4).

If air-flow velocity reduces again, " sand dune " that local location exists in the pipeline is big suddenly to the material bolt that becomes filling whole pipe section, (except the conveying of bolt stream) can cause material not readvance in pipeline (pipe choking), the system failure (seeing Fig. 5) when material bolt long enough.

The present main flow Pneumatic Conveying Technology of using, material belongs to Fig. 3 and Fig. 4 form in the flow regime of delivery pipe.

Analyze material the flow regime of delivery pipe as can be known (can referring to as Chen Hongxun chief editor relevant strength conveyings such as " pipeline mass transport and engineering application " aspect monograph), existing Pneumatic Conveying Technology has determined from mechanism: need higher delivery speed how to make the desirable fluidised form of particle (material) maintenance very crucial end blocking pipe, the course of conveying to prevent that material is deposited on to manage, thereby determined existing Pneumatic Conveying Technology to have shortcomings such as energy consumption is big, component wear serious, carry easily obstruction, fed distance is restricted.

3, purpose

The present invention adopts brand new conveying technology (mechanism), reaches the purpose that solves the existing above-mentioned shortcoming of Pneumatic Conveying Technology.

4, technical scheme

It is that three parts are formed (step) that the electrostatic suspension conveying technology can mainly indignantly be drawn together: 1. delivering gas ionization produces a large amount of only with the gas ion of same sex electric charge; 2. particle (material) is charged; 3. utilize the same sex electric charge principle of repelling each other to carry out electrostatic suspension and carry.

4.1 ionization of gas

The very big corona discharge electrode of surface curvature (discharge electrode) (with air duct and pipe atmosphere outside as another utmost point) is set in the passage that delivering gas flows, apply dc high voltage (positive electricity or negative electricity) to corona discharge electrode during work and make corona discharge electrode generation bunch discharge (point discharge), forming corona zone (shared volume is little relatively in the passage of corona zone in air flows) near the corona discharge electrode, bunch discharge makes ionization of gas, in the corona zone, generate a large amount of free electron and positive ion, and adhering to and electronegative gas molecule by free electron---negative ion (can be captured by gas molecule after bumping against with gas molecule by the free electron that corona discharge electrode produces, and be attached to gas molecule and form negative ion).

When corona is very negative (negative corona), then because the effect of electric field force, positive ion also neutralizes thereon to the corona discharge electrode motion, negative ion and free electron move outside the corona zone in the effect of electric field force, thereby outside the corona zone, formed unipolar space-charge region (negative charge), because gas flow, the gas that only contains a large amount of same sex electric charges (negative ion and free electron) is brought in the follow-up flow process by air-flow and (is seen Fig. 6,1-gas molecule, 2-negative ion, 3-free electron, 4-corona zone, 5-positive ion, 6-corona discharge electrode, 7-air by-pass passage).

Equally,, then enter the gas in the follow-up flow process, only contain a large amount of positive ions when very timing of corona (positive corona).

According to test, coaxial garden cylindrical electrode makes corona discharge electrode gas produce critical voltage (initial corona voltage) u of bunch discharge ₀For:

(1) when adopting clean, smooth cylinder section corona wire,

For negative corona: $u_0=r(31.02\mathrm{\ρ}+9.54\sqrt{\frac{\mathrm{\ρ}}{r}})\×{10}^3\ln \frac{R}{r}----\left(V\right)$

For positive corona: $u_0=r(33.7\mathrm{\ρ}+8.13\sqrt{\frac{\mathrm{\ρ}}{r}})\×{10}^3\ln \frac{R}{r}----\left(V\right)$

In the formula: r, R-are respectively the radius (cm) of corona wire and air flow passage;

ρ-gas density the factor; $\mathrm{\ρ}=\frac{298p}{101325(273+t)}$

P-gas absolute pressure (Pa);

The t-gas temperature (℃).

(2) when adopting prickle shape corona discharge electrode:

In the formula: the radius of curvature (cm) of a-prickle shape corona discharge electrode thorn point;

ρ-gas relative density factor coefficient of correction.

The operating voltage of delivering gas ionization is generally 40～80kV.According to circumstances ionization of gas also can be arranged in the delivery pipe of expecting gas mixture and carry out.

4.2 particle (material) is charged

In order to realize electrostatic suspension and conveying, particle must be as early as possible, as far as possible how charged, and particle generally can adopt diffusional charging or/and electric-field charge (when the material that is transferred all is fines, can not establish the electric-field charge device).

(1) diffusional charging

According to the molecular theory of gas theory, carry the gas of a large amount of same sex ions (positive ion or negative ion), because the unordered heat motion of ion and concentration difference diffusion, ion moves to particle surface, at delivery pipe or/and in sending jar with particle (material) collision, ion sticks on the particle and makes charging particle.Ignoring under the external electrical field condition, the time is that the carrying capacity (by the negative ion analysis) of t particle during second is:

$q=\frac{2\mathrm{\&pi;}{\mathrm{\&epsiv;}}_0\mathrm{dkT}}{e}\ln (1+\frac{N_0{e}^2\mathrm{<figure-callout\; id="2"\; label="d"\; filenames="A20041001400700161.png"\; state="\{\{state\}\}">d</figure-callout>}}{2{\mathrm{\&epsiv;}}_0\sqrt{2\mathrm{m\&pi;kT}}}t)----\left(c\right)$

In the formula: k-Baltzmnn constant, k=1.3804 * 10 ^-23(J/ ℃);

The grain of d-particle (material) is through (m);

T-absolute temperature (K);

ε ₀-gas specific inductance capacity, ε ₀=8.85 * 10 ^-12(F/m);

The e-electron charge, e=1.6 * 10 ^-19(C);

N ₀-ion concentration (1/m ³);

M-mass of ion (kg).

(2) electric-field charge

At the top of delivery pipe particle the electric-field charge device is set and (sees Fig. 7,1-power supply, 2-electric charge field, 3-delivery pipe), ion clashes into particle under the effect of extra electric field, and stick on the particle and make it charged and (should adopt alternating electric field, in order to avoid particle is partial to a side of delivery pipe), and the carrying capacity that reaches capacity as early as possible.

The electric field strength E that electric charge field produces ₀:

$E_0=\frac{V}{b}----(V/m)$

In the formula: V-imposes on the voltage (V) of electric field;

B-electric field pole distance between plates (m).

The saturated carrying capacity q of particle _Ps:

$q_{\mathrm{ps}}=\frac{3{\mathrm{\&epsiv;}}_r}{{\mathrm{\&epsiv;}}_r+2}\mathrm{\&pi;}{\mathrm{\&epsiv;}}_0{d}^2{E}_0----\left(C\right)$

In the formula: the grain of d-particle (material) is through (m);

ε _rThe relative dielectric coefficient of-particle (material), general in 5～6 scope, pottery 4.4, quartz 3.75, gypsum 5.

The charged time constant t of particle ₀:

$t_0=\frac{4{\mathrm{\&epsiv;}}_0}{N_{0}e{k}_i}----\left(s\right)$

In the formula: k _iMechanical mobility (the m of-gas ion ²s ^-1V ^-1), at 0 ℃, air (dried): k during 1atm _i=2.1 * 10 ^-4(negative ion), 1.36 * 10 ^-4(positive ion); Air (very dried): k _i=2.5 * 10 ^-4(negative ion), 1.8 * 10 ^-4(positive ion).

Time is the carrying capacity q of t particle during second _p:

$q_p=q_{\mathrm{ps}}\frac{t}{t+t_0}$

Get N ₀=10 ¹⁴Individual/m ³, T=300K, m=5.3 * 10 ^-26Kg, k _i=2.2 * 10 ^-4m ²s ^-1V ^-1, V=6000V, b=0.3m, the particle that can obtain different grain warps under diffusional charging and electric-field charge synergy, the electron number of charged gained (n=q/e) and situation is as follows over time:

Table 1 charging particle amount (electron number)

The particle grain is through (μ m)	Time (s)
					????0.001	??0.01	??0.1	??1.0
	????1.0	????15	??37	??60					??82
????10.0					????399	??908	??1420	??1687
	????50.0	????4055	??12683	??21348					??23899
????100.0					????12097	??44545	??77136	??85267
	????500.0	????202352	??972200	??1745578					??1907445

4.3 particle (material) electrostatic suspension is carried

In material gas mixture delivery pipe pipe or pipe outer " suspension electrode " is set or with delivery pipe as " suspension electrode ", apply electric charge (for example employing: 1. apply vdc with the electrically charged particle same sex for " suspension electrode " to " suspension electrode "; 2. the very big discharge electrode of surface curvature is set, applies dc high voltage with the electrically charged particle same sex, discharge electrode generation point discharge to discharge electrode during work; 3. electrostatic induction ... etc. method), make " suspension electrode " carry electric charge with the electrically charged particle same sex, set up the suspension electric field, utilize the same sex electric charge principle of repelling each other, make the particle (material) in the delivery pipe under the effect of electric field force, be in suspended state, and, realize the electrostatic suspension conveying not to the pipe bottom sediments.

The setting of " suspension electrode " and execute electric mode and can adopt various schemes proposes two kinds of embodiments below, electrostatic suspension is carried be described further:

(1) in the bottom of material gas mixture delivery pipe " suspension electrode " (seeing Fig. 8,1-electrically charged particle, 2-delivery pipe, 3-DC high-voltage power supply, 4-discharge electrode, 5-suspension electrode) is set

The electric field intensity (perpendicular to " suspension electrode " direction) that " suspension electrode " produces:

${\mathrm{<figure-callout\; id="1"\; label="E"\; filenames="A20041001400700161.png"\; state="\{\{state\}\}">E</figure-callout>}}_1=\frac{\mathrm{\&lambda;}}{2\mathrm{\&pi;}{\mathrm{\&epsiv;}}_{0}a}----(V/m)$

In the formula: λ-" suspension electrode " go up per unit length with electric weight (being the electric charge linear density) (C/m);

The a-electric field intensity calculates the vertical distance (m) of point apart from " suspension electrode ";

ε ₀-gas specific inductance capacity, ε ₀=8.85 * 10 ^-12(F/m);

Because delivery pipe is for only containing the delivering gas (charge cloud) of a large amount of same sex electric charges (positive charge or negative charge), the electric field intensity that charge cloud produces is:

${\mathrm{<figure-callout\; id="2"\; label="E"\; filenames="A20041001400700161.png"\; state="\{\{state\}\}">E</figure-callout>}}_2=\frac{{\mathrm{<figure-callout\; id="2"\; label="q\; r"\; filenames="A20041001400700161.png"\; state="\{\{state\}\}">q</figure-callout>}}_r}{2\mathrm{\&pi;r}{\mathrm{\&epsiv;}}_0}----(V/m)$

In the formula: q _r-radius is a delivering gas (charge cloud) in the cylinder of r, per unit length with electric weight (C/m).

Carrying capacity is the particle (material) of q, and the electric field force that is subjected in the electric field that " suspension electrode " produced is:

F＝q(E ₁-E ₂)????(N)

Because " suspension electrode " is arranged in the bottom of delivery pipe, thereby the suffered electric field force F direction of electrically charged particle is opposite with the gravity mg direction of particle.

For example: thermal power plant's ash transfer, particle real density ρ _p=2100kg/m ³, the charged time is 0.1 second, " suspension electrode " goes up the electric charge linear density is 10 ^-6When C/m, particle were a=2mm apart from the vertical distance of " suspension electrode ", the suffered electric field force F of electrically charged particle with the ratio of gravity mg was:

Table 2 electric field force F/ gravity mg

The particle grain is through (μ m)	????1.0	????10.0	????50.0	????100.0	????500.0
						Electric field force/gravity	????7985	????188	????22.6	????10.2	????1.84

(2) with delivery pipe as " suspension electrode " (seeing Fig. 9,1-electrically charged particle, 2-delivery pipe (suspension electrode), 3-direct supply)

Apply vdc (being equally applicable to " suspension electrode " of other form) for " suspension electrode ", because delivery pipe is for only containing the delivering gas (charge cloud) of a large amount of same sex electric charges (positive charge or negative charge), the current potential that charge cloud produces at delivery pipe inwall place is (current potential of getting some earth of unlimited distance is zero):

$U_d=\frac{{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="A20041001400700161.png"\; state="\{\{state\}\}">r</figure-callout>}}^2\mathrm{\&rho;}}{2{\mathrm{\&epsiv;}}_0}----\left(V\right)$

In the formula: ρ-charge cloud volume density (C/m ³), ρ=eN ₀

On Fig. 5 and " suspension electrode " shown in Figure 4, apply vdc (current potential), in the delivery pipe during for (or for bearing) electric charge just, then apply current potential than " current potential that charge cloud produces at delivery pipe inwall place " higher (or lower), " suspension electrode " is identical with the charged polarity of charge cloud, the electric field that difference of potential produces, electrically charged particle electric field in the electric field force that is subjected to be (pointing to pipeline center):

$F=\frac{|U-{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="A20041001400700161.png"\; state="\{\{state\}\}">r</figure-callout>}}^2\mathrm{\&rho;}/\left(2{\mathrm{\&epsiv;}}_0\right)|}{R-r}----\left(N\right)$

For example: thermal power plant's ash transfer, particle real density ρ _p=2100kg/m ³, the charged time is 0.1 second, when U=60kV, R=0.1m, particle were a=2mm apart from the vertical distance of " suspension electrode ", the suffered electric field force F of electrically charged particle with the ratio of gravity mg was:

Table 3 electric field force F/ gravity mg

The particle grain is through (μ m)	????1.0	????10.0	????50.0	????100.0	????500.0
						Electric field force/gravity	????11423	????268	????32.3	????14.6	????2.6

4.4, the energy consumption of electrostatic suspension conveying technology (is example as " suspension electrode " with delivery pipe) and conventional Pneumatic Conveying Technology compares

The energy of particle swarm (material) delivery consumes mainly is made up of two parts:

(1) material moves the energy A that is consumed in pipeline section ₁

A ₁＝q _ms·f·L _e·g????(J/s)

In the formula: the equivalent length of Le-delivery duct (m)

The g-acceleration due to gravity, 9.81m/s ²

The friction coefficient of f-material and pipeline, this coefficient is relevant with material characteristic, conveying tubing, Guan Jing etc.

Carry (is example as " suspension electrode " with delivery pipe) for electrostatic suspension, because of material does not contact with delivery pipe, material is that the air that is not ionized (not with the plus or minus ion) contacts with the delivery pipe inwall in course of conveying, thereby desirable f=0.

For the air-transport system of routine, friction coefficient f is:

$\left\{\begin{array}{cc}f=0.70& (D\&le;0.203m)\\ f=1.1-\frac{50}{25.4}D& (D\&GreaterEqual;0.203m)\end{array}\right.$

In the formula: warp (m) in the D-delivery duct

(2) the energy A that carries the friction of air and delivery duct to be consumed ₂

$A_2=22.965\frac{{{\mathrm{<figure-callout\; id="1"\; label="Q"\; filenames="A20041001400700161.png"\; state="\{\{state\}\}">Q</figure-callout>}}_1}^2}{D^{5.31}{\mathrm{\&rho;}}_1}{q}_{\mathrm{ma}}{L}_e----(J/s)$

In the formula: Q ₁Volume of air flow (the m at-delivery duct top ³/ min).

Warp (m) in the D-delivery duct

P ₁Absolute pressure (the N/m at-delivery duct top ²)

q _Ma-conveying MAF (kg/s)

Electrostatic suspension is carried and the energy consumption coefficient of comparisons C of conventional Pneumatic Conveying Technology is (ignore the electrostatic suspension system energy consumption, see 4.5 for details):

$C=\frac{A_2}{{\mathrm{<figure-callout\; id="1"\; label="A"\; filenames="A20041001400700161.png"\; state="\{\{state\}\}">A</figure-callout>}}_1+A_2}=\frac{1}{1+f{\mathrm{\&mu;}}_{m}g{D}^{5.31}{\mathrm{\&rho;}}_1/\left(22.965{{\mathrm{<figure-callout\; id="1"\; label="Q"\; filenames="A20041001400700161.png"\; state="\{\{state\}\}">Q</figure-callout>}}_1}^2\right)}$

In the formula: μ _m-mass transport mass ratio (kg/kg)

For example: carry thermal power plant's fly ash, mass transport mass ratio μ _m=25kg/kg, the absolute pressure P at delivery duct top ₁=3 * 10 ⁵N/m ², through D=0.2m, friction coefficient f=0.7 then gets the air rate v at delivery pipe top in the pipeline _a=8m/s, then the volume of air flow Q at delivery duct top ₁=15.1m ³/ min.

Thereby calculate C=0.343, promptly electrostatic suspension carry the energy consumption of thermal power plant's fly ash be about conventional Pneumatic Conveying Technology energy consumption 1/3.

4.5, the determining of electrostatic suspension system capacity

The electrostatic suspension system capacity should be not less than the energy that particle swarm suspends and consumes.

(1) the energy A of particle swarm suspension consumption _Xf

A _xf＝mg·v _n????(W)

In the formula: the quality (kg) of material in the m-delivery pipe;

The g-acceleration due to gravity, 9.81m/s ²

v _n-delivery pipe endoparticle group's floating velocity (m/s).

m＝q _ms·L/v _s

q _MsThe mass flow rate of-material (kg/s);

L-delivery pipe geometrical length (m);

v _sThe average velociity (m/s) of material in the-delivery pipe.

(2) particle swarm floating velocity v _n

(a) particle reynolds number Re

$R_e=\frac{v{d}_s{\mathrm{\&rho;}}_m}{\mathrm{\&mu;}}$

In the formula: the suitable speed (m/s) between v-particle and the air-flow;

d _s-particle grain is through (m);

ρ _m-gas density (kg/m ³);

The kinetic viscosity of μ-gas (Pas)

(b) when Stokes district (Re＜1), particle swarm floating velocity v _n

$v_n=\frac{k{d_s}^2({\mathrm{\&rho;}}_p-{\mathrm{\&rho;}}_m)g}{18\mathrm{\&mu;}}$

In the formula: k-grain shape and transportation concentration influence coefficient, k＜1;

ρ _p-particle real density (kg/m ³).

(c) when Allen district (1≤Re≤500), particle swarm floating velocity v _n

$v_n=k\&CenterDot;\frac{4}{225}\&CenterDot;{\left[\frac{{({\mathrm{\&rho;}}_p-{\mathrm{\&rho;}}_m)}^2{\mathrm{<figure-callout\; id="2"\; label="g"\; filenames="A20041001400700161.png"\; state="\{\{state\}\}">g</figure-callout>}}^2}{{\mathrm{\&rho;}}_m\mathrm{\&mu;}}\right]}^{\frac{1}{3}}\&CenterDot;d_s$

(d) when Newton district (Re＞500), particle swarm floating velocity v _n

$v_n=k\&CenterDot;\sqrt{3g\frac{d_s({\mathrm{\&rho;}}_p-{\mathrm{\&rho;}}_m)}{{\mathrm{\&rho;}}_m}}$

(3) thermal power plant's ash transfer sample calculation

The particle grain is through d _s=60 * 10 ^-6M, particle real density ρ _p=2100kg/m ³, carry density of air ρ _m=1.2kg/m ³, kinetic viscosity μ=18.2 * 10 of air ^-6Pas, the mass flow rate q of material _Ms=16.67kg/s (system exert oneself 60t/h), the average velociity v of material in the delivery pipe geometrical length L=1000m, delivery pipe _s=5m/s.

Suppose grain shape and transportation concentration influence coefficient k=1, then count particles group floating velocity v _nThe quality m=3333 (kg) of material in the=0.226m/s, delivery pipe, the energy A that particle swarm suspends and consumes _Xf=7390W, i.e. 0.123kWh/ (tkm), the particle swarm energy that consumes that suspends is so little, almost can ignore.

5, beneficial effect

Electric field force expression formula according to particle (material), nearer apart from " suspension electrode ", electric field is bigger to the application force of particle (material), on " suspension electrode ", carry (applying) when suitable electric charge (current potential) is arranged, can guarantee that the electric field force of all particles (material) in course of conveying is greater than gravity, make material remain desirable suspended state, promptly under the effect of electric field force, particle (material) is in suspended state all the time and can not manages bottom sediments, even the speed in the delivery pipe is zero, as long as charging particle and " suspension electrode " electric field exist, the desirable suspended state of particle (material) just can keep, thereby:

(1) the electrostatic suspension conveying technology of the present invention's proposition, avoided existing air-transport system: " particle (material) because of action of gravity at the pipe bottom sediments; the fluidised form of material gas mixture in the delivery pipe is worsened; fed distance is far away; fluidised form worsens more obviously, thereby makes its fed distance restricted " shortcoming.Can realize long distance conveying by failure-free.

(2) realized the stable conveying of low speed or Ultra-Low Speed, when material contacted with delivery pipe, abrasion loss was directly proportional with 2～3 powers of speed, transporting resistance is directly proportional with 1～2 power of speed.

Simultaneously when suitable " suspension electrode " is set, can realize that convey materials does not contact with delivery pipe, but the air that is not ionized (not with the plus or minus ion) contacts with the delivery pipe inwall.

1. component wear can be significantly reduced, even the wearing and tearing of material can be avoided parts;

2. transporting resistance is minimum, can significantly cut down the consumption of energy.

(3) under the effect of electric field force, even the speed in the delivery pipe is zero, the desirable suspended state of particle (material) still can keep, and therefore can avoid the generation of plugging phenomenon.

Claims (3)

1, a kind of bulk material Pneumatic Conveying Technology (electrostatic suspension Pneumatic Conveying Technology): make the particle (material) that is transferred charged, utilize the same sex electric charge principle of repelling each other, make particle (material) be in suspended state under the effect of electric field force, the realization material can not be deposited on the pipe end and/or not contact with delivery pipe when carrying.

2, electrostatic suspension Pneumatic Conveying Technology according to claim 1 is characterized in that: along delivery pipe setting " suspension electrode " or utilize delivery pipe as " suspension electrode ", and make " suspension electrode " carry electric charge (current potential) with the electrically charged particle same sex.

3, electrostatic suspension Pneumatic Conveying Technology according to claim 1 is characterized in that: delivering gas produces a large amount of only with the gas ion of same sex electric charge, by diffusional charging or/and electric-field charge makes particle (material) charged fast.

Images