Background technology
High-temperature dust removal technology is the visual plant that the field Energy-saving in Industrial Furnaces such as metallurgy, the energy, chemical industry, material, burning reduce discharging.International in the research of high-temperature dust removal technology, mainly contain the forms such as cyclone dust removal, high-temperature electric dedusting, the filtration of ceramic chimney filter, the filtration of metal chimney filter and Bed Filtration.
Middle low temperature cyclone dust collectors (<400 ℃) are widely used, be characterized in simple in structure, processing ease, cheap, but efficiency of dust collection is not high, even the most efficient cyclone dust collectors, for 50 μ m dust, efficiency of dust collection can only reach 96% left and right; To 5 μ m dust, only has 73% left and right; And to 1 μ m, be only 27% left and right.For high-temp. vortex dedusting, it is large that dusty gas viscosity becomes, and the hot properties of particle also changes, and cyclone dust removal effect is poorer.Therefore, even three cyclone dust collectors series connection, dust removing effects can not meet environment protection emission requirement, and cyclone dust collectors can only be as pre-dedusting.
The states such as U.S., moral, Japan are explored for high-temperature dust removal electric cleaner.At present, existing reaching under 650~790 ℃, 570kpa moved the experimental record of 100 hours, and efficiency of dust collection can reach 95%~99.5%.But have that corona discharge is unstable, electrode life is short, to problems such as smoke components sensitivity, high-temperature insulations, in the short time, be difficult to break through.
The outstanding advantages of pottery chimney filter is that filter efficiency is high, and outstanding problem is that availability and reliability are low, exists such as seal failure between tube-to-tube sheet connection; Thermal shock, mechanical shock cause screen pipe brittle failure; The grey bridge squeeze crack screen pipe that expands with heat and contract with cold between pipe; Thermal creep; With composition reaction-sintered or localized hyperthermia's sintering such as alkali metal; The problems such as permanent ash deposition crust.
Metal chimney filter is larger than ceramic chimney filter intensity, thermal conductance good, and filtering layer is thin, and resistance reduces, and outstanding problem is that non-oxidizability, corrosion resistance, temperature tolerance are low, under oxidizing atmosphere heatproof lower than 450 ℃, under reducing atmosphere lower than 600 ℃.
Bed Filtration is high temperature resistant, corrosion-resistant, economical and practical reliable, outstanding problem is to being less than 10 μ m grits, particularly low to submicron particle filter efficiency.
Through research, find, Bed Filtration is high temperature resistant, corrosion-resistant, economical and practical reliable, if can make Bed Filtration bring up to ceramic chimney filter level to micron and submicron particle filter efficiency, so certainly will become the most competitive high-temperature dust removal technology.
Analyze domestic and international Research Literature known, improve Bed Filtration efficiency, must reduce stratum granulosum particle diameter of filter medium, but it is also limited reducing stratum granulosum particle diameter of filter medium.Particle diameter is too little, stratum granulosum pressure drop increases too fast, for moving granular bed, just has to improve stratum granulosum translational speed, cause the changing of the relative positions between particle to produce greatly reentrainment of dust, make on the contrary filter efficiency reduce, and for fixed bed, high pressure drop lower surface muffin is easily bored a hole, make filter efficiency fast-descending, so only depend on, reduce stratum granulosum particle diameter of filter medium, it is limited improving filter efficiency, is difficult to fundamentally solve the inefficient problem of Bed Filtration.
In order fundamentally to solve the inefficient problem of Bed Filtration, University Of Ningbo poplar state grey hair understands multilayer filtering material particle bed steps level filtration new technology, and basic principle is: multilayer filtering material particle bed is comprised of upper and lower two-layer filtrate, also can be comprised of upper, middle and lower three-layer filter.Upper strata filtering material particle is large, space is large, and dust containing capacity is large, pressure drop is low, is deep-bed filtration characteristic, can rise and improve bed dust containing capacity, prolongation cleaning cycle, the effect of protection fine grained layer; Intermediate layer filtering material particle is thinner, is shallow-layer filtering feature (dust infiltrate filtering layer shallow and lack), plays further to protect fine grained layer; Lower floor's filtering material particle is the thinnest; filter material layer surface can form muffin; with dirt filter dirt; be surface filtration characteristic, high efficiency is intercepted and captured micron and submicron particle, particularly because there has been the protection of upper strata filtrate, middle level filtrate; can make the dust concentration that arrives this fine grained layer be reduced to 1/75~1/200 of upper strata filter material layer entrance dust concentration; reduce widely the growth rate of fine grained layer muffin pressure drop, significantly improve the filter efficiency of fine dust, extend cleaning cycle.
The core that multilayer filtering material particle bed steps level is filtered new technology is: step filters, that is: coarse media filters meal dirt, thin media filtration fine dust, thus reaching high efficiency and low pressure drop, this is that any individual layer filtering material particle bed all can not reach.
The ingenious part that multilayer filtering material particle bed steps level is filtered new technology is: the particle diameter of each metafiltration material successively reduces from top to bottom successively, the grain density of each metafiltration material successively increases from top to bottom successively, make the step filtration successively of each metafiltration material, and can be under same gas speed common fluidisation, deashing is and mixed mutually mutually fast, step strainability is forever constant.Existing several typical granular bed filter dedusting technologies being done to one below simply introduces.
Rake deashing stratum granulosum dirt catcher.This is that a kind of stratum granulosum is positioned over the online fixed bed filtering device of horizontal screen, and its adopts revolution rake to stir filtering layer and in conjunction with return air deashing.Once manufactured and sold by German Munich cleaner company the seventies.Once there were tens cement plants that this filter has been installed.But rake is just bad within approximately 1 year.This device shortcoming is that jam, wearing and tearing easily appear in the transmission mechanism of comb rake, and screen cloth is easily prematured by solids etc.
Dust remover with boiling-particle layer.This is also that a kind of stratum granulosum is positioned over the online fixed bed filtering device of horizontal screen, filter process is similar with single rake, during deashing, blowback air blasts through airflow-distribution board below stratum granulosum with certain flow rate and pressure, make stratum granulosum be fluidization (being fluidized state), the dust that makes to amass in stratum granulosum comes off because colliding between particle, rubbing, and by blowback air-flow, is taken away, and reaches the object of stratum granulosum deashing.Ducon company proposed the gravel bed filter of this fluidization reverse gas cleaning mode in 1970, and had designed several forms, but not commerical test and application.
Cross-flow type moving bed stratum granulosum dirt catcher.Cross-flow type moving bed stratum granulosum dirt catcher is a kind of pattern that moving bed stratum granulosum dirt catcher occurs the earliest, basic principle is, filtrate keeps certain thickness vertical filtering layer under the clamping of screen cloth or venetian blind type plate, and move from top to bottom because of Action of Gravity Field, dusty gas level is passed through stratum granulosum, form cross-current, dust is held back by filtering layer, and gas is purified.In the paper that nineteen ninety-five delivers, report that India is developing a kind of moving bed filter, for the dust removal by filtration of PFBC high-temperature flue gas.The filtrate that is characterized in circulating adopts pneumatic conveying mode, and filtrate is separated by top one inertia separator with dust, and strength carries the ash-laden gas of use to be purified by cyclone dust collectors and sack cleaner two-stage series connection.
Without sieve adverse current mobile layer filter.Without sieve adverse current mobile layer filter, be to be developed by American Studies, filter diameter has reached 4m, has reached the scale of commercial Application.The nineties, hot working research institute of China national Utilities Electric Co. did not research and develop without sieve adverse current mobile layer filter pilot system under country's 95 key scientific and technological projects and the subsidy of state key base research and development planned project yet.
Summary of the invention
The problem existing in order to solve prior art, the invention provides a kind of deduster that can at high temperature reach good dust removing effects.
In order to realize above object, technical scheme of the present invention is as follows: a kind of biomass high-temperature deduster, comprise resistant to elevated temperatures casing, casing has fuel gas inlet, gas outlet and impurity discharging opening, described box inside wall is installed lautertuns and lay filter screen in described lautertuns, above filter screen, be also covered with one deck filter medium to filter impure biological fuel gas, the bottom of described lautertuns has the air compartment that holds clean biological fuel gas, this air compartment is communicated with gas outlet, described gas outlet connects anti-blowpipe, described cabinets cavity is cubic cavity, lautertuns is positioned at the left side, impurity outlet is positioned at following right-hand member.
Further, described lautertuns is comprised of Turbogrid plates, side plate and the swash plate with grid, the Turbogrid plates that side plate connection level is laid and the swash plate of inclination, and Turbogrid plates, side plate and swash plate enclose with box inside and surround air compartment.
Described side plate is mutually vertical with Turbogrid plates, and swash plate and horizontal angle are 10~20 °.
Described side plate is also connected with guide plate.
Described side plate, swash plate and guide plate insulation material parcel are wherein.
Described anti-blowpipe is provided with switch valve.
Between the gas outlet of described anti-blowpipe and switch valve, offer blowback entrance.
Described casing top offers the mouth that gives out of gas, and at mouthful installation explosionproof water seal device that gives out of gas.
Described box inside is provided with preheating burner near fuel gas inlet place.
Compared with prior art, the present invention owing to being provided with lautertuns in casing, and the air compartment of lautertuns is communicated with gas outlet, and gas outlet connects anti-blowpipe.When impure biological fuel gas is in entering casing, big and heavy impurity sedimentation exports in impurity, and light thin impurity still follows combustion gas through lautertuns, and under the obstruct of filter medium, light thin Impurity deposition is in filter medium top layer, through the clean combustion gas of filtering, enter air compartment, by gas outlet, discharged; When impurity is excessively deposited on filter medium top layer, pressure drop is increased, even affect upstream equipment and normally move, now, by to the reverse non-combustible gas that is blown into of anti-blowpipe, make the impurity of deposition hike up and drop to impurity outlet, reach the object that impurity is stopped up in automatic removing.Compared with manually when remove stopping up impurity, in the need casing of etc.ing, temperature is reduced to and is applicable to the manual work temperature method of operation again, and the present invention can realize automatic removing obstruction operation, more convenient and quicker, less manpower under the condition of high temperature.
The specific embodiment
As shown in Figure 1, hot precipitator is comprised of casing 1, lautertuns 2, filter screen 3, explosionproof water seal 5 and anti-blowpipe 6.The inner chamber of casing 1 is cubic cavity, casing top offers fuel gas inlet 7, casing left side opening is provided with gas outlet 8, lower box takes over and offers impurity discharging opening 9, the left inside side of casing is installed two cover lautertuns 2, and gas outlet 8 connects anti-blowpipe 6, and anti-blowpipe is provided with stop valve 10, between stop valve 10 and gas outlet 8, offer blowback entrance 20, impurity discharging opening 9 connects discharge bucket 21.
As shown in Figure 2, lautertuns is by Turbogrid plates 11, skeleton with build material 14 and form.Turbogrid plates 11 are horizontally disposed with, and for laying the punctulate filtration part of tool, it sparsely offers grid 16, and the area of grid 16 is at least 9.0cm
2.Skeleton is connected to form by side plate 13, swash plate 12 and guide plate 15.Side plate 13 vertically arranges, and its same side is connected with Turbogrid plates 11 and swash plate 12, swash plate 12 be positioned at Turbogrid plates 11 below, swash plate 12 is positioned at the lower end of side plate 13.Swash plate 12 becomes 15 ° of angles with horizontal line face.The end face of the medial surface of the bottom surface of Turbogrid plates 11, side plate 13 and swash plate 12 surrounds a semi-enclosed air compartment 22 jointly, and air compartment 22 is communicated with gas outlet 8.The upper end of side plate 13 connects the guide plate 15 of inclination, and guide plate is outward-dipping.In order to strengthen the intensity of skeleton and high temperature resistant, skeleton need wrap up one layer of heat preservation and build material 14.As shown in Figure 3, the overall width of lautertuns is 1 meter to 3 meters, and inside side 17 is all closely attached on before and after casing, side 18 is closely attached on the left inside side of casing and forms filter element.Turbogrid plates 11 are laid one deck filter screen 3 above, pore diameter 1mm left and right on filter screen, and spread quartz sand 4 as filter medium at filter screen.
In order to prevent from occurring HTHP in casing and to cause danger, at casing top, also offer diffusion mouth 19, and at diffusion mouth 19, explosionproof water seal device 5 is installed.For the temperature at deduster initial operating stage approaches biological fuel gas temperature as early as possible, thereby light in advance the object that the combustion gas that enters deduster reaches preheating deduster, near fuel gas inlet place, be provided with burner 23.