SU1368573A1 - Method of using combustible waste of celluloze production - Google Patents

Abstract

The invention relates to the disposal of combustible waste by burning in a fluidized bed; a layer of inert coolant to meet environmental requirements and is aimed at intensifying the process of burning waste cellulose production and improving the efficiency of flue gas cleaning from sulfur oxides in the layer by enhancing heat and mass transfer. After partial dewatering, the waste is fed to the incineration bed in an inert heat transfer fluid. In the surface region of the layer, horizontal encounters are initiated and pairwise brought into shock interaction. jet streams. Many small horizontal opposing jets in the lower part of the layer, ensuring its liquefaction, are also coupled into shock interaction. The use of the shock interaction of many small opposite jets eliminates stagnant zones and obtains a uniform fluidized mass of the layer. j i (L

Description

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The invention relates to the utilization of 1F1I by burning combustible waste from the jyllose industry, for example, dehydrated sulfite stones, wood debarking waste, sewage sludge, and can be used in the power industry for burning low-grade fiber TOPLIV, for example peat.

The purpose of the invention is to intensify the process of burning pulp production waste and to increase the efficiency of flue gas cleaning with tons of sulfur oxides.

The essence of the method consists in supplying combustible materials to the fluidized bed, in which the fluidization of the bed is carried out by introducing into the lower part of the bed a multitude of small horizontal c; dust, brought in pairs to the impact i: oe interaction. In the upper part- and layer to intensify the process- (LOB heat and mass transfer initiating 5pot 1 oriental counter-jet jets, also in pairs driven and shock interaction. Afterburning is carried out over the layer by entering ({acute blow,

i Such a scheme of organization of the process allows by shock interaction of two opposite flows of the mixture: from the upper part of the layer to intensify heat and mass transfer both by increasing the relative speeds, hooks and by developing hydrodynamic efforts, while the residence time of the particle in the active zone depends only on its mass (the greater the mass of the particle, the longer its residence time in the bed), and the temperature level in the bed is governed by the consumption of air for liquefaction (the temperature is greater as the coefficient of excess is closer to unity, air),

The use of the shock interaction of a multitude of small oncoming jets in the lower part of the bed to liquefy the volume of the inert heat carrier allows, on the one hand, to eliminate stagnant zones and, on the other, to obtain a homogeneous fluidized bed mass. If necessary, simultaneously with incineration, to conduct the purification process of dym gases from sulfur oxides (sulfur dioxide) by binding them to the sulphates directly in the layer, the proposed method will allow to increase the degree of purification not only by increasing the mass exchange with increasing relative speeds, but and in connection with the constant renewal of the surfaces during the collision in the upper and lower counter-jet streams, when the reacted surface of the additive fractions consisting of sulphate falls off,

10 Example 1, Utilization of pod-, wood debarking waste in quantities of fOOO kg / h, of which 500 kg / h are the bark after mechanical pressing with a humidity of 65% and

15 500 kg / h - sawdust with a humidity of 40%, Total air flow rate Q BxeixV 2400, where about 1.2 - excess air as compared with theoretically necessary for full combustion of the top 20, V ° 2.0 - theoretical air flow It is necessary to incinerate 1 kg of wood waste.

The air consumption for fluidization (in the lower part of the bed) is

25 1000 at oi 0.5, Air consumption for initiation of counter-jets in the upper part of the layer is 1000 at ci 0.5, and the air-to-ear consumption for an acute blast over the layer

30 tavl 400 when "g 0,2,

Chamotte chips with an average fraction of 2 mm were selected as the inert heat carrier for the bed, and they are poured into the device to a level of 25 n supply of opposing air jets in the upper part of the bed.

When air is supplied to the liquefaction, small opposite horizontal jets in the lower part of the layer are

40 U ust) 16 mm, colliding, are elongated into bubbles and: pressed upward, liquefying the layer located above them. The height of the bed is increased by about 1.7 times, flooding from 45 to 100 mm for the supply of opposing jets of air in the upper part of the bed. To warm up the layer, air for liquefaction is supplied heated to 400 ° C, and after the layer reaches this temperature, pneumatic conveying into it, together with the air of the upper oncoming jets, begins to feed sawdust, which, when burned out, contribute to further temperature increase. When the temperature reaches 600-700 C, the crust from the top starts feeding the crust while simultaneously increasing the air supply to the blast in the upper part of the layer to the calculated speed (60 m / s) and flow rate (1000 nm / h).

Large and small wood waste mixed with chamotte crumble heated to 800–900 ° C; the TC into the countercurrent flows in the upper part of the layer are picked up by them, impacted and partially carried into the superlayer space. When a collision goes th furnace burners, is introduced into the layer

Intensive heat exchange between the hot inert heat carrier and fractions of wood waste, which are intensively dried at the same time, is crushed and hot. Large fractions, whose own soaring speed is greater than the speed of the ascending flow, return to the layer after the impact, and the small ones burn in air. sharp blowing over the layer.

Thus, regulation of the residence time of the fuel fractions in the bed is provided. When the initial moisture content of the waste changes, the required temperature level in the bed volume is maintained by changing the air flow rate for fluidization within the limits of the value of the excess air coefficient 0.3-0.7 (on average 0.5) from the theoretically necessary for complete fuel burn-up; the excess, the more the temperature ate.

Example 2. Sulfite alkali is utilized by burning. ka with a sulfur content of 9% per working mass. According to the conditions of observance of the purity of the atmospheric air,

and the sprayed nozzle liquor is ignited.

Head air jets in the upper part of the fluidized bed diameter

15 rum t 50 mm involve a mixture of burning particles of limestone and a burning crater in a counter movement and bring into a collision, which sharply intensifies the burning and the process of bonding.

20 of sulfur oxides, since during the creation of lime fractions, calcium sulphate layers formed by the binding of sulfur dioxide are lost on them. In this way

25, the continuous access of sulfur oxide to the active surface of limestone is maintained, which increases the efficiency of sulfur dioxide trapping and makes it possible to use lime more fully.

Claims (1)

Invention Formula The method of utilization of combustible waste of cellulose production, including their partial dehydration, under the fire and burning in a fluidized bed of an inert heat carrier, in which they initiate horizontal opposing 35 Lime lime with a fraction of 6 mm is used as an inert material and sulfur dioxide binder (SOj). After fluidization with layers of air, as in Example 1, and heating it to 400-450 ° C. In some way, for example, using paradise. The liquor sprayed by the nozzle is ignited. The oncoming jets of air in the upper part of the fluidized bed with a diameter of 50 mm involve a mixture of red-hot limestone particles and a burning liquor in an opposite movement and collide, which sharply intensifies the combustion and sulfur oxide bonding process, as in the collision of limestone fractions Calcium sulphate layers, resulting from the binding of sulfur dioxide, are deposited from them. In this way, Sulfur dioxide is continuously accessible to the limestone active surface, which increases the efficiency of sulfur dioxide capture and allows limestone to be used more fully. Invention Formula The method of disposal of combustible waste cellulose production, including their partial dehydration, feeding and burning in a fluidized bed of an inert heat carrier, in which they initiate horizontal opposing bake the flue gas cleaning from oxide-40 jet streams, ensuring it sulfur catch (bind and withdraw from cycle). The consumption of liquors evaporated to 50% of moisture is 1000 kg / h. The total air flow with an excess of about 1.2 is Q BxcixV 1800 (the designations are the same as in the previous example). Air consumption for liquefaction at. about 0.3 is 450. Air flow to organize counter jet streams in the upper part of the layer at ui 0.7 is 1050 nm / h. The air consumption for a sharp blast at about 0.2 is 300. liquefaction and afterburning of fine fractions using an acute blow, which is due to the fact that, in order to intensify the combustion process and increase the efficiency of flue gas cleaning from sulfur oxides, horizontal opposite jet streams in the surface region of the layer are additionally initiated and them in shock interaction, with horizontal, counter-jet jets, ensuring the liquefaction of the layer, also in pairs result in shock interaction. 50 liquefaction and afterburning of fine fractions using an acute blow, which is due to the fact that, in order to intensify the combustion process and increase the efficiency of flue gas cleaning from sulfur oxides, they additionally initiate horizontal countercurrent jets in the surface region of the layer and in pairs lead them in shock interaction, with horizontal, counter-jet jets, ensuring the liquefaction of the layer, also in pairs result in shock interaction. 0