Cloud formula dust pelletizing system
The present invention relates to a kind of dust pelletizing system, be specifically related to one and utilize cloud principle to dust catching especially to the cloud formula dust pelletizing system that fine particle (PM2.5) traps.
Atmosphere pollution is one of key factor affecting China's environment, and wherein dust pollution is the pith of atmosphere pollution.Research shows, the fine particle (PM2.5) in dust is easy to heavy metal in enriched air, acidic oxide, organic pollution, bacterium and virus etc., its to the harm of health far above coarseparticulate.Therefore, control dust pollution, the discharge especially controlling fine particle is significant.(magnifying year, the research of Inhalable Particulates in Urban Ambient Air, [J] Shanghai environmental science, 1999,18(4): 154-157)
Current industrial conventional dust pelletizing system has cyclone dust collectors, electrostatic precipitator, sack cleaner, wet scrubber etc.Wherein wet scrubber is simple with its structure, equipment investment is low, efficiency of dust collection is high and the feature such as the ability having absorbing sulfur dioxide in flue add alkaline matter in its water after, is widely used in the coal-burning boiler system of big and medium-sized cities.(Zhang Dianyin, Wang Chun. dedusting handbook [M]. Chemical Industry Press, 2004.)
Wet scrubber is that dusty gas is fully contacted with liquid (being generally water), utilizes the effects such as inertial collision, interception and diffusion to be separated from dusty gas by particle.Wet scrubber is divided into by engineering low energy and high energy two class.The pressure loss of low energy wet scrubber is 0.2-1.5kPa, but it is very low to the particulate burning purifying efficiency of less than 10 μm; The purification efficiency of high-energy wet type dust remover can reach 99%, but its pressure loss is 2.5-9.0kPa.(Jiang Zhanpeng, Yang Hongwei. Environmental Engineering [M]. Higher Education Publishing House, 2013.)
But, the wet scrubber used at present exposes the problem that some have generality gradually in actual motion: the flue gas with water of 1. discharging is serious, this not only can cause the sticky ash of draught fan impeller, produces abnormal vibrations, and understands heavy corrosion fan blade and back-end ductwork; The flue-gas temperature fall of 2. discharging is excessive, and this rising height that chimney can be made to discharge flue gas reduces, and then has influence on pollutant dilution diffusion in an atmosphere in flue gas, can cause the local air pollution of chimney near zone.(Dong's Peng, Li Jun etc. wet scrubber is in operation problems analysis, [J] electric power station system engineering, 2006,22(6): 29-30)
Traditional wet process of cleaning mainly relies on the method for mechanical spraying that aqueous dispersion is become tiny drop, is undertaken catching dirt by the inertial collision of drop and diffusion precipitin.The collecting effect of general spraying to fine particle dust (PM2.5) is not good, mainly because the particle diameter of water smoke too large (particle diameter 200 ~ 600 μm).(Chen Zhuokai, Chen Fanzhi, etc. the application of Atomization Water Made by Ultrasonic Technique in Dust Removal Experiment [J]. Guangdong chemical industry, 2006,33(10): 74-77)
Through retrieval, Chinese patent application 200810091426.7 discloses a kind of high-efficiency wet-type dust collector, not only increase the collection efficiency to PM2.5, also efficiently solve the problem of equipment corrosion, but still do not solve the shortcomings such as traditional wet deduster water consumption is large, energy consumption is high, blowdown easily blocks, maintenance cost is high.
Summary of the invention
The invention provides a kind of cloud formula dust pelletizing system, under the operating mode of height containing Dust Capacity, have good separating effect to fine particle.
For this reason, the present invention adopts following technical scheme:
A kind of cloud formula dust pelletizing system, this dust pelletizing system comprises the device producing relative humidity supersaturation water smoke, the supersaturation water steam that this device generates fully mixes with fine particle in the flow field of disturbance, and saturated vapor take fine particle as the nuclei of condensation liquefies and be attached to fine particle surface, fine particle particle diameter is constantly increased, to improve the hydrophilicity of fine particle, and increase volume and the weight of fine particle, and then facilitation is played to the trapping of fine particle; Meanwhile, the drop in supersaturation water smoke and fine particle collide mutually, merge, reunion microphysical processes, to promote the trapping to fine particle further; And discharge a large amount of anions in this process and fine particle produces electrostatic reaction, be conducive to the sedimentation of fine particle.
This system is charging aperture foremost, and this charging aperture measures district successively and seals and be communicated with mist generator or atomization box, germination district or expansion joint, cloud formula collecting region or cloud formula dust arrester, air-introduced machine, exit concentration; Dirt discharge groove is communicated with bottom germination district or expansion joint; Ash exhauster is communicated with and the outlet of germination district or expansion joint is tangentially communicated with cloud formula collecting region or cloud formula dust arrester bottom cloud formula collecting region or cloud formula dust arrester.
Described mist generator or atomization box are supersonic atomizer or high-pressure nozzle atomising device or shower nozzle atomising device.
The described ash exhauster port of export adopts water-stop.
Described germination district or expansion joint are erect or accumbency is placed.
Described mist generator or atomization box and germination district or expansion joint become one.
Dust-contained airflow stops more than 2s in described germination district or expansion joint.
Described cloud formula collecting region or cloud formula dust arrester are primarily of the coaxial central cylinder, middle cylinder, the outer cylinder body composition that arrange, have cavity, each other seal isolation each other, the bottom of this three cylindrical shell is cone structure and the cone distal end of middle cylinder and outer cylinder body is inside and outside underflow opening, and this inside and outside underflow opening is connected with ash exhauster by flange; The outlet of germination district or expansion joint and between described middle cylinder and outer cylinder body the tangential entry of cavity upper end through; Several small cyclones separators with the center of three cylindrical shells for axle is evenly fixed on the inwall of middle cylinder; The junction of middle cylinder and its underpart cone is connected with base plate, leaves air inlet annular distance between the outer rim of this base plate and the inwall of middle cylinder; The bottom discharge mouth of several small cyclones separators described to be fixed on base plate and and the cone of middle cylinder bottom through; The upper end of several small cyclones separators described has air inlet, and the inner chamber of this air inlet and middle cylinder is through; The outlet of these several small cyclones separator upper ends by bend pipe and central cylinder through; Described bend pipe is placed in the top seal at outer cylinder body top, and this top cover has outlet.
The cross section of described winding pipe exit and the angle of horizontal plane are 90
The present invention adopts " cloud " physics, collision reunion principle, provides the fine particle gathering-device of the features such as the high and low cost of a kind of efficiency of dust collection, floor space are few.The present invention is mainly applicable to the collection of fine particle PM2.5, can be used for the trapping of dust in industrial production, indoor-outdoor air purification etc., plays the effect of dust suppression dedusting, reduces fine particle to the harm of health.
Reunite before dust enters collecting region in the present invention and grow up, significantly reduce fluid drag, then removed by deduster.Both taken into account that cyclone dust removal structure is simple, reduced investment, occupation of land small scale, energy consumption was low, easy and simple to handle, easy to maintenance, total efficiency of separation is high, the advantage of stable performance, had again the feature of efficient trapping fine particle.Experiment shows, the present invention can reach 99.6%-99.9% to the clearance of dust, also will reach 95% to fine particle (PM2.5) trapping.With different dedusting technology as the present invention, electrostatic precipitator, sack cleaner, cyclone collection different-grain diameter fine particle dusts, laser particle analyzer is utilized to analyze the classification efficiency of different-grain diameter dust after collection, as shown in Figure 4.Can find out, the present invention to the collection efficiency of PM2.5 all higher than other several dedusters.
Compared with traditional wet process of cleaning, traditional wet process of cleaning is using drop as catching dirt body, such as, adopt the method for mechanical shower nozzle that cleaning solution is dispersed into tiny drop, and inertial collision, the interception of main dependence drop are caught and carried out catching dirt with the form of diffusion precipitin.Because the particle diameter of its water droplet is excessive, trapping poor effect for fine particle, and the size droplet diameter little (being generally less than 5 μm) that " cloud " technology produces, specific area is large, and evaporation rate is high, and dust-containing area steam can be made to evaporate rapidly, form supersaturated environments, be that the nuclei of condensation liquefy again with dust granules, dust granules particle diameter constantly increased, raises the efficiency.Moreover, " cloud " technology, the water yield of use is few, there is not the problem that accessory substance in wet dust collection technology is difficult to collection and secondary pollution.
Analyze it from structure of the present invention below and how to reach described effect.
1. in outer cylinder body with cyclone separator, achieve two-stage to be separated, outer cylinder body and the mutually isolated sealing of cyclone separator, make not interfere with each other mutually between two-stage separation, remove the fine particle of different-grain diameter respectively, efficiency of dust collection improves greatly;
2. solve a tolerance difficult problem pockety in small cyclones separator parallel process.Air-flow, through tangential entry, produces eddy flow in outer cylinder body, finally evenly enters some small cyclones separators, in small cyclones separator, efficiently carries out fine particle collection.
3. by Clausius-C1apeyron equation
learn, water saturation vapour pressure increases along with the rising of temperature, and when temperature is 10 DEG C, water saturation vapour pressure is about 1200Pa.For cyclone separator, be higher-pressure region near outer wall, center is negative pressuren zone.The pressure of the outer wall of cyclone separator is far above 1200Pa, and temperature is lower than 10 DEG C, and the gas containing steam condenses rapidly in outer wall higher-pressure region.So, utilize cyclone separator near outer wall layer be the rapid condensing zone of high pressure, the feature forced down of central gas, dusty gas, in higher-pressure region rapid condensation, is conducive to being separated.4. small cyclones separator upper end outlet is bend pipe, can guarantee that static pressure aspirates, and makes each small cyclones separator tolerance even.
5. dusty gas flows out from small cyclones separator upper end outlet, pours in central cylinder, and in central cylinder, some strands of dusty gases collide mutually, disturbance, thus make particle continue to grow up, and are conducive to the collection of particle, realize the third level and are separated.
6., before cloud formula collecting region or the dedusting of cloud formula dust arrester, atomizing humidifying performance process is carried out to dust-contained airflow, makes full use of " cloud " physics principle, high efficiency collection is carried out to fine particle.Adopt advanced electroacoustic transduction ultrasonic atomization or high-pressure nozzle spray technique, water consumption is very low, produce finely dispersed Micron-order high-density fine droplet, drop rapid vaporization produces partial over saturation steam, supersaturated vapor is fully combined with fine particle, and particle growth district is provided, allow fine particle grow up, finally efficiently remove fine particle.
7. cyclone separator of the present invention adopts several small cyclones separators to be connected in parallel (current cyclone separator mainly with being used alone, air quantity is uneven, efficiency is low), and each small cyclones separator intake and the more current cyclone separator of pressure distributing homogeneity obtain and improve greatly.
Accompanying drawing explanation
Fig. 1 is schematic block diagram of the present invention;
Fig. 2 is the cutting structural representation of cloud formula collecting region of the present invention or cloud formula dust arrester;
Fig. 3 is the schematic top plan view of Fig. 2;
Fig. 4 is the present invention and sack cleaner, electrostatic precipitator, cyclone dust collectors, the dust removing effects comparison diagram of wet scrubber in certain power plant's Dust Removal Experiment;
Fig. 5 is that the present invention and wet scrubber are to the classification efficiency comparison diagram of different-grain diameter particle;
Fig. 6 is the present invention and the Philips air purifier dust removing effects figure at different time;
Fig. 7 is the present invention and the Philips air purifier removal VOCs design sketch at different time;
Fig. 8 is that the present invention and Philips air purifier are to the classification efficiency comparison diagram of different-grain diameter particle.
Detailed description of the invention
Below in conjunction with accompanying drawing, the present invention and effect thereof are further illustrated.
Embodiment 1, with reference to Fig. 1, a kind of cloud formula dust pelletizing system, this device is charging aperture 1 foremost, and this charging aperture 1 measures district 8 successively and seals and be communicated with mist generator or atomization box 2, germination district or expansion joint 3, cloud formula collecting region or cloud formula dust arrester 5, air-introduced machine 7, exit concentration; Dirt discharge groove 4 is communicated with bottom germination district or expansion joint 3; Ash exhauster 6 is communicated with and the outlet of germination district or expansion joint 3 is tangentially communicated with the upper end of cloud formula collecting region or cloud formula dust catcher device bottom cloud formula collecting region or cloud formula dust arrester 5.Wherein, described cloud formula collecting region or cloud formula dust arrester 5(are with reference to Fig. 2, Fig. 3) form primarily of coaxial setting, the central cylinder 14 each other with cavity, each other seal isolation, middle cylinder 27, outer cylinder body 23, the bottom of this three cylindrical shell is cone structure, and the cone distal end of middle cylinder 27 and outer cylinder body 23 is inside and outside underflow opening 10,24, this inside and outside underflow opening 10,24 is connected with ash exhauster 6 by flange; It is through that the outlet of germination district or expansion joint 3 and the cavity between described middle cylinder 27 and outer cylinder body 23 pass through tangential entry 22; Several small cyclones separators 28 with the center of three cylindrical shells for axle is evenly fixed on the inwall of middle cylinder 27; The junction of middle cylinder 27 and its underpart cone is connected with base plate 11, leaves air inlet annular distance 26 between the outer rim of this base plate 11 and the inwall of middle cylinder 27; The bottom discharge mouth 9 of several small cyclones separators 28 described to be fixed on base plate 11 and and the cone of middle cylinder 27 bottom through; The upper end of several small cyclones separators 28 described has air inlet 29, and the inner chamber of this air inlet 29 and middle cylinder 27 is through; The outlet of these several cyclone separator 28 upper ends by bend pipe 12 and central cylinder 14 through; The top cover 13 that described bend pipe 12 is placed in outer cylinder body top seals, and this top cover 13 has outlet 15.
The angle of the cross section that described bend pipe 12 exports and horizontal plane is 90
o, pressure drop is uniformly distributed.
Described ash exhauster 6 is made up of bed material groove 17, connection valve 19, U-shaped pipe 20; Described bed material groove 17 one end is connected by flange 16 with described inside and outside underflow opening 10,24, and the other end is connected with U-shaped pipe 20 by connection valve 19, and the other end of this U-shaped pipe 20 is sewage draining exit 21; The bottom of bed material groove 17 is provided with blowoff valve 18.
Described mist generator or atomization box 2 are supersonic atomizer or high-pressure nozzle atomising device or shower nozzle atomising device.
Embodiment 2, mist generator or atomization box 2 are linked in sequence not according to shown in Fig. 1 with germination district or expansion joint 3, but mist generator or atomization box 2 are arranged on germination district or expansion joint 3 side, charging aperture 1 is directly connected with germination district or expansion joint 3, the fog that mist generator or atomization box 2 generate carries out negative pressure suction from germination district or expansion joint 3 side, and dust-contained airflow and fog directly contact in germination district or expansion joint 3.Remaining with embodiment 1.
Embodiment 3, described mist generator or atomization box 2 can be arranged in germination district or expansion joint 3 and make both become one.Remaining with embodiment 1.
Embodiment 4, the cloud formula collecting region in embodiment 1 or cloud formula dust arrester 5 with several cyclone separator and joint group, several electrostatic precipitator the replacement such as joint group, wet scrubber.
Embodiment 5, the cloud formula collecting region in embodiment 1 or cloud formula dust arrester 5 can be in parallel multiple.Several bifurcated pipe roads are divided into from expansion joint exit pipeline, be connected respectively to the import of several cloud formula collecting regions or cloud formula dust arrester, several cloud formula collecting regions or the parallel placement of cloud formula dust arrester, the outlet of these several cloud formula collecting regions or cloud formula dust arrester remerges in a pipeline, is then connected to fans entrance.Such connection can guarantee that air quantity in each cloud formula collecting region or cloud formula dust arrester is even, and the collection making several cloud formula collecting regions or cloud formula dust arrester simultaneously carry out fine particle.Dust removing effects of the present invention as shown in Figure 4.
workflow of the present invention:
Under air-introduced machine 7 acts on, dust-contained airflow tangentially enters the cavity between outer cylinder body 23 and middle cylinder 27 by the tangential entry 22 of cloud formula collecting region or cloud formula dust arrester 5 upper end, produces rotating flow, under centrifugal action, carries out first order separation.Isolated coarse granule or drop will fall the cone inwall of outer cylinder body 23 lower end, discharge through outer underflow opening 24.The air-flow be separated through the first order to enter the bottom of middle cylinder 27 through air inlet annular distance 26, then from cyclone separator 28 upper end air inlet 29 rotate into each cyclone separator 28 respectively, cyclone separator 28 in, generation rotating flow, carries out second level separation.For cyclone separator, be higher-pressure region near outer wall, center is negative pressuren zone.Be 10 in temperature
oduring C, water saturation vapour pressure is about 1200Pa, and the gas containing steam condenses rapidly in higher-pressure region, and dust granules is grown up.Gas condensation containing fine particle becomes drop, and the inwall along cyclone separator flows down, and is entered in the cone of middle cylinder 27 lower end by discharging opening 9, in this cone, speed is almost nil, pressure drop is also very little, and drop can flow down along cone inwall, discharges from interior underflow opening 10.Have an exit bend 12 respectively at the outlet ends of each cyclone separator 28, what ensure generation on the one hand is static pressure, instead of dynamic pressure, avoids the impact to top cover 13, and inhibition of impurities flows backwards simultaneously; Ensure that the air quantity of cyclone separator is uniformly distributed on the other hand.Air-flow after treatment enters into the central tube 14 of cloud formula deduster by exit bend 12.In central tube 14, the air-flow that multiple exit bend 12 is released collides mutually, and fine particle is grown up again, realizes the third level and is separated.Under blower fan 7 suction function, the clean gas flow after dedusting is through exporting 15 outer rows.
Before equipment runs, first to water filling fluid-tight in ash exhauster 6, make to be full of in device the water liquid level of the U-shaped pipe (can not lower than the minimum level of separator), prevent air access to plant.Along with dust-laden liquid flows out from underflow opening, the liquid in blowdown apparatus gets more and more, and outwardly can discharge, at sewage draining exit 21 times termination one container collection sewage, also can connect a blow-off line in its lower end, realize automatic pollution discharge.Regularly open blowoff valve 18, blowdown cleaning is carried out to device.
the test of dust removing effects of the present invention is as follows:
Test 1: certain power plant's dedusting.
Charging aperture concentration (g/m
3) be 0.2,0.5,1,2,5,30.
Start air-introduced machine 7, under the condition of negative pressure that air-introduced machine 7 produces, dust-contained airflow enters atomizing generator 2 from charging aperture 1, then germination district 3 is admitted to, enter cloud formula collecting region or cloud formula dust arrester 5, by air-introduced machine exhaust outlet be discharged to exit concentration measure district 8, survey exit concentration with dust instrument, exit concentration and efficiency of dust collection as shown in the table.Change the present invention into sack cleaner, electrostatic precipitator, cyclone dust collectors and wet scrubber, measure pressure drop and calculate efficiency of dust collection.As shown in Figure 4, obviously, the dust removing effects of cyclone dust collectors is too low, cannot reach high standard requirement in several efficiency of dust collection contrast; Electrostatic precipitator is once invested greatly, and equipment operating cost is high; Sack cleaner easily occurs sticking with paste bag phenomenon because spraying water, and air-flow, by not smooth, causes cloth bag to continue dedusting; Wet dust removal can make equipment corrosion and energy consumption is large, and efficiency of dust collection of the present invention is high a lot.
With air quantity 1200m
3/ h is example, test cloud formula dust pelletizing system and the efficiency of dust collection of wet scrubber, and uses laser particle analyzer to survey its classification efficiency respectively to after different diameter airborne particle sampling, and classification efficiency corresponding to different diameter airborne particle as shown in Figure 5.Now the liquid-gas ratio of wet scrubber is 0.5L/m
3.Can find out that cloud formula dust pelletizing system is less than the fine grain arresting efficiency of 10um apparently higher than wet scrubber to particle diameter.And wet dust removal water consumption per hour is 600L, and cloud formula dust pelletizing system is only 40L, greatly reduces water consumption.
Test 2: laboratory the present invention and air purifier are to the contrast of fine particle (PM2.5) collecting effect.
At enclosed ventilation cupboard internal-combustion fragrant incense, leave standstill 1h.Under the effect of air-introduced machine negative pressure, dusty gas enters the purification of cloud formula dust pelletizing system, and purified gas sends fume hood inside again back to, and fume hood internal gas flow is circulated.Measure PM2.5 and VOCs concentration in fume hood with PM2.5 detector, measure the collection efficiency of different-grain diameter range of particle simultaneously with dust instrument and laser particle analyzer.Cloud formula dust pelletizing system and air purifier to PM2.5 and VOCs in fume hood at the clean-up effect of different time as Fig. 6, Fig. 7, to the collection efficiency of different-grain diameter range of particle as shown in Figure 8.As can be seen from Fig. 6, Fig. 7, compared with air purifier, cloud formula deduster is easier drops to minimum in the shorter time by PM2.5 and VOCs concentration in fume hood, and minimum is lower than air purifier.As can see from Figure 8 along with the increase of grain diameter, the collection efficiency of two kinds of dust arresters improves all thereupon.When grain diameter is 2.5 μm, the collection efficiency difference 99.61% and 91.56% of cloud formula dust pelletizing system and air purifier.
Experiment 3: laboratory the present invention is to the clean-up effect of vehicle exhaust
In order to study cloud formula dust collection method to the clean-up effect of vehicle exhaust, in test, the charging aperture of automobile engine tail gas outlet with cloud formula dust pelletizing system is connected, and a certain proportion of alkaline solution is added in the solution of mist generator, utilize the negative pressure of air-introduced machine, the tail gas produced by engine, successively by mist generator, germination district, cloud formula deduster, measures fine particle, CO, NO and SO respectively in exit
2concentration, and calculate its removal efficiency.Removal efficiency is as shown in the table.
As can be seen from the table, cloud formula dust collection method can reach 98% to the removal efficiency of fine particle in vehicle exhaust, and can remove NO, SO completely
2deng pernicious gas.
As can be seen from the Comparative result analysis of above three tests, the scope of application of the present invention is very wide, has more considerable dust removing effects at industrial production, indoor air purification, automobile exhaust pollution in administering, and obvious to the collecting effect of fine particle PM2.5.For increasing of fine particle in current air, we have to pay attention to its impact on human body health.But the dust arrester efficiency existed at present is generally low, especially very pessimistic to the removal of fine particle (PM2.5).Cloud formula dust pelletizing system has abandoned in traditional dust collection method the principle and method filtering and adhere to, makes full use of " cloud " physics, first makes fine particle particle size growth, promote that it is effectively collected.Can say that the progress of important breakthrough is played in the collection of cloud formula dust pelletizing system to PM2.5.