CS212255B2 - Method of combustion of materials containing the carbon - Google Patents

Abstract

1510946 Fluidized-bed combustion METALLGES AG 9 July 1976 [5 Sept 1975] 28750/76 Heading F4B A process for combustion under approximately stoichiometric conditions in which carbonaceous material is fed through a lance 7 to a fluidized-bed reactor 1 which is fluidizedby gas supplied through an inlet 8 and by a secondary gas supplied through an inlet 2 or which can be supplied at a plurality of superimposed levels (2a-2d), Fig. 2 (not shown). At least the secondary gas contains oxygen for the combustion of the carbonaceous material in the fluidized bed. The volume ratio of fluidizing gas supplied at 8 to secondary gas supplied at 2 is in the range from 1 : 20 to 2 : 1 and the two gas supplies are adjusted so that suspension density of the fluidized bed above the inlet 2 level is in the range 15 to 100 Kg/M<SP>3</SP>. Solids entrained by the exhaust gas from the fluidized-bed are collected in the separator 6 and are recycled through a conduit 9 back into the reactor 1. Surplus solids produced are withdrawn through a conduit 10. Part of the heat of combustion is dissipated through cooling surfaces 3 in the space above the inlet 2 level. Other heat heat exchange surfaces may be located at positions 4 and 5 in the reactor and separator. Solids discharged from the conduit 10 may be fed to a fluidized-bed cooler 14, which is fluidized by oxygen containing gas which is then fed to the inlet 2. The cooler 14 has cooling registers 13 in which solids are cooled indirectly by gas supplied through a conduit 17 and later fed as fluidizing gas to the inlet 8. Part of this gas supply may be used for pneumatically feeding the carbonaceous material through the lance 7. The combustion process may be carried out under superatmospheric pressure.

Description

The invention also relates to a method for the near-stoichiometric combustion of carbon-containing materials in a fluidized bed, with the reintroduction of the discharged solids into the fluidized bed and the removal of the combustion heat through the cooling surfaces.

Numerous aggregates have already been used to burn carbon-containing materials · Among other things, it is known to use fluidized bed reactors operating in the aforementioned manner ·

In the known methods, it is disadvantageous to work with a relatively low bed height in order to keep the pressure drop within reasonable limits and that the cross-mixing of the solid in the vortex bed is disrupted due to the arrangement of cooling surfaces in the lower reactor space. uneven temperatures, especially overheating and cinder formation, and in addition it is only very imperfect to adapt the operation of the reactor to the current and substantially fluctuating power; or by eliminating individual reactor units.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method which avoids the known, in particular the aforementioned disadvantages, without increasing the cost of the apparatus and the process.

The invention consists essentially in that the combustion is carried out with oxygen-containing gases which are fed in two partial streams at different heights, at least one of which is fed as a secondary gas to one plane or to several planes one above the other. the fluidizing gas and the secondary gas are adjusted in the range between 1:20 and 2: 1-, a fluidized bed having an average slurry value of 15 to 100 kg / m ² is formed above the secondary gas inlet by adjusting the secondary gas velocity and the fluidizing gas / secondary gas ratio; at least a substantial part of the combustion heat is removed by means of cooling surfaces arranged above the secondary gas inlet in the free space of the furnace, the bulk of the carbon-containing material is introduced into the free space below the secondary gas inlet, virtually free of installations; flue gas, a separator and a return line.

The principle of the fluidized bed used in the present invention is essentially characterized in that, unlike a classical fluidized bed in which the dense phase is separated by a distinct density jump from the gas space above it, the distribution ratios in this case are without limit determination layers. There is no jump in density between the dense phase and the dusty space above it, but the solids concentration inside the reactor is constantly decreasing from bottom to top.

They are based on Froude and Archimedes when defining operating conditions

area as follows: at ² µg 0.1 3 3/4. ------- -------- 10 g. d pk - pg optionally 0.1 4 Ar * 100 whereas . g (pk - pg) Ar = —------------- 2 Pg. v ⁴

It means:

u relative gas velocity ø / s

Ar Archimedes coefficient

Pg gas density kg / m 2 pk solid particle density kg / m 2

d. diameter of spherical particle m & p in kinematic viscosity m / s g gravity acceleration m / s

The division of the oxygen-containing gases which are generally necessary for combustion into two partial streams at different heights causes the combustion to be carried out in two stages. This achieves a soft combustion, i.e., combustion without local overheating, which not only ^{ye s} torch consists ^of measurement of slag but zloven sn ^IZI formed ETAK ^acid-d with US ^CART todnoty to below 100 ppm.

Due to the fact that there are practically no installations in the reactor space below the secondary gas supply, a good distribution of the carbon-containing feed material is achieved immediately. Rapid mixing with hot bedding also ensures good ignition of the fuel. Use of carbon-containing material - in the form of fine-grained, average grain diameter 30 to 25 ^ and ^{Get-y l} while in the ^{hill-to-amortized} REITs ^to é real time.

The fluidized bed reactor may have a rectangular, square or circular cross section. The lower part of the reactor may also be conical, which is particularly advantageous for large reactor cross sections and when using an inert gas as a fluidizing gas.

The velocities of the gases present in the fluidized bed reactor are generally greater than 5 m / s at normal pressure and can be as high as 5 m / s. 10 m / s.

The ratio of the diameters to the height of the reactor should be chosen such that the residence time is 0.5 to 0.8 s, preferably 1 to 4 s.

In practice, any gas which would not adversely affect the condition of the flue gas can be used as the fluidizing gas. It is advisable to use inert gases such as recycled flue gases, nitrogen and water vapor. However, in order to intensify the combustion process, it is advantageous if a partial stream of oxygen-containing gases is fed to the reactor as a fluidizing gas.

Thus, in carrying out the process according to the invention, the following two possibilities are possible:

1. An inert gas is used as the fluidizing gas. It is then necessary to introduce the oxygen-containing combustion gas as a secondary gas in at least two planes one above the other.

2. Oxygen-containing gas is used as fluidizing gas. Then it is sufficient to introduce the secondary gas in one plane. It goes without saying that even with this solution the secondary gas supplied can still be divided into several planes.

It is advantageous to provide several secondary gas supply openings in each plane.

In a preferred embodiment of the process according to the invention, the secondary gas is supplied at the highest point at a height of up to 30% of the total height of the fluidized bed reactor, but at least 1 m above the fluidizing gas supply. In this filling, if the secondary gas is supplied in several planes, the operation is adapted to the height position of the highest secondary gas line. The ^HEAD and ^y face ^s is ^d at ^the Tosti-Proceed with the ^L cal ^{- P} free space only ^p ro ^p RVN ^s with ^p and ^L EDGINGPROFILE ^and cold ^p en ^t EME ^R p ^p adhere a reaction between a material containing carbon and a gas containing whether it is supplied as a fluidizing gas or a secondary gas in a plane lying below. On the other hand, it is possible to provide sufficiently large cooling surfaces in the upper space of the reactor above the secondary gas supply.

Further cooling surfaces can be obtained if additional cooling surfaces are provided on the reactor wall. These cooling surfaces may also overlap the wall in the lower region of the reactor, since this does not adversely affect the mixing of solids. The wall itself can also be designed as a cooling surface.

The cooling surfaces are generally formed by rectangular walls of forced-circulation tubes at a clear distance of at least 150 mm, preferably 250 to 500 mm. Such cooling surfaces are also used for wall cooling. The pipe axes are to be parallel to the flow direction of the gas and solids suspension, thereby minimizing erosion. This, however, is associated with a slightly reduced heat transfer per unit of cooling surface compared to the arrangement of the tubes with a horizontal axis and thus perpendicular to the flow direction. However, since in the process according to the invention large cooling surfaces can be provided in the reactor and optionally in the downstream separation and return unit, the reduced heat transfer is irrelevant.

If the carbon-containing materials have only a few, non-combustible fractions, the use of free heat after it is taken from a circulating system made up of a fluidized bed reactor, a trap and a return line is not economical. However, if the content of such proportions is high, it is advantageous to utilize the heat content, which can be accomplished by cooling the solid in a vortex cooler. For an optimum heat balance, according to a longer solution of the process according to the invention, it is advantageous that in the combustion of residual-rich fuels the residues are cooled in a vortex cooler provided with a plurality of successively flowing chambers. or - as a secondary gas, so that the heat content of the solids returns to the combustion process.

In addition, it is advantageous to extract heat from the flue gases of the fluidized bed reactor. This can be done by working with the technique common to steam boilers or by passing the flue gas with a particular advantage as a fluidising gas into a vortex cooler. The vortex cooler, formed, for example, as a Venturi mixer, may have a rectangular, square or circular cross-section and may be formed by tubular walls. The heat exchange can optionally be carried out with a coolant flowing in the tube bundle. Both cooling methods can be used together. The most efficient coolant is water, which is then heated and then fed to evaporate and / or overheat the cooling surfaces of the reactor for high-altitude combustion.

In order to keep the sulfur content low, it is advantageous to carry out - combustion - in the presence of a fine-grained desulfurizer such as lime, dolomite and the like. The desulfurizers, which should also have a granularity of the carbon-containing solid material, are introduced in the simplest manner together with the material.

An increase in the power at a given reactor size can be achieved by using the combustion process according to the invention instead of air with oxygen-enriched air and / or under pressure, preferably up to 20 atp. In contrast to operation with air or operation at normal pressure, it is then necessary to increase the cooling surfaces, for example by installing additional cooling registers in the reactor space above the secondary gas line. When using oxygen enriched air, the density of the suspension in the reactor space above the secondary gas should ^b YT 15 and ^from I ⁰⁰ kg / m, ^m, and ^L in this ^CMD pa e ^{d h} of Buffer ^T and thermal ^eh of current is in ^ETSI and at higher the solids content is achieved by higher heat transfer coefficients.

A particular advantage of the method according to the invention is that it can be easily adapted to the instantaneous power consumption, which in practice varies considerably. According to another feature of the invention, the combustion power is controlled to match the power of the slurry density in the space formed above the secondary gas inlet of the combustion reactor. in the buoyancy.

A certain heat transfer is associated with a certain operating condition at predetermined volumes of fluidizing gas and secondary gas and the resulting medium slurry density. The heat transfer to the cooling surfaces is increased by increasing the suspension density by increasing the amount of fluidizing gas and possibly also the secondary gas. With the increased heat transfer, at virtually constant firing temperatures, the possibility of dissipating the heat generated by the increased combustion capacity is given. The increased oxygen demand required as a result of the increased combustion capacity is automatically provided by using an increased amount of fluidizing gas and optionally a secondary gas to increase the density of the slurry.

Analogously, the combustion power can be controlled by reducing the density of the slurry in the space formed above the secondary gas inlet of the fluidized bed reactor to accommodate the reduced reactor power. Reducing the density of the slurry also reduces heat transfer so that less heat is removed from the reactor. The combustion performance can be reduced. essentially without changing the temperature. '

The carbon-containing material is fed in the usual manner by means of at least one blower pipe, for example by pneumatic blowing. As a result of the favorable mixing, a relatively small number of blowers is sufficient for this and, with the small dimensions of the fluidized-bed reactor, only one blower is sufficient.

Resupply of solid combustion residues entrained by the exhaust gas from the reactor · prov ^{and a} di · C ^yk lonovým separator, or OHY ^b em ^'p rou ^d u ^p l ^y n ^{u, PRICE} EMZ in ^ lation ^P ro ^PE tn ^{s lecture} IV ^and events they may advantageously be provided with cooling surfaces with parallel flow.

Final purification of the gases can be carried out in a conventional manner, for example by means of an electro filter. In this case, it is possible to return the separated solids to the reactor in order to achieve the lowest possible carbon content in the flue gas.

The process according to the invention is particularly suitable for the combustion of all kinds of coal, coal scrubbers, fly ash, bituminous shale, as well as fuel oils and mixtures thereof. When using fuel oil as a carbon-containing material, it is necessary to form a bed of, for example, fine-grained lime or dolomite or other mineral substances.

A great advantage of the process according to the invention is the fact that the combustion of the carbon-containing materials achieves a hitherto unsatisfactory temperature constant by means of the entire circulating system, which consists of a fluidized bed reactor, a trap and a return line. Due to the intense movement of solids, there are no temperature gradients, so 'overheating of individual solid particles is prevented.

In a preferred embodiment of the process according to the invention with the addition of a desulfurizer, a high temperature constant also has a positive effect on the desulfurization of the flue gas. This is because the desulphurization agents retain their activity and thus the ability to bind sulfur due to the high temperature constant. The high fineness of the desulfurizer promotes this advantage, since the surface to volume ratio for the sulfur binding rate, determined essentially by the diffusion rate, is particularly favorable.

^{Bp dl} caused by ev ^y n and ^l Cutting moreover enables the ^PL n ^e combustion ^and to the mater ^ial for ohsahuj ^I No ^{larger-carbon} with oxygen whose amount is above the stoichiometric demand pouze.nepatrně. The excess oxygen is generally less than 10%.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a fluidized bed reactor with a cylindrical reactor space; FIG. hover combustion with a cylindrical reactor space and a conical bottom portion; and FIG. 3 is a cross-sectional view of the hover combustion reactor of FIG. 1 with associated devices.

The fluidized bed reactor 6 is provided with cooling surfaces J above the secondary gas line 2. Further cooling surfaces 6, 1 are arranged on the wall of the reactor 6 or the separator 6, which forms a unit with the reactor 6. For the sake of clarity, unlike the preferred embodiment, the cooling tubes are chosen horizontally.

In operation, carbonaceous material, fluidizing gas line 8, and secondary gas line 2 are supplied to the fluidized bed reactor 6 through the lance. In the region between the second pipe and the secondary gas inlet of the fluidizing gas creates a relatively dense fluidized bed and the density of the slurry may reach almost to the material density pypné LO ^from e. Above potrubta 2 ^{to P} ro und ^{A p} lyn RNI is roofs ^H and the suspension of Buffer ^{T 1 to 5-100} g / rn \

The solids discharged with the flue gas from the reactor 6 are separated from the flue gas in the separator

212255 6 and are discharged back via line 2 to reactor 1. Excess solids are discharged via line 60.

The fluidized bed reactor 6 in FIG. 2 is formed with a conical bottom. The secondary gas is supplied here via lines 2a. 2b 2c 2d. which - are arranged at different heights. Other parts otherwise correspond to the embodiment of Fig. 1.

In the embodiment according to FIG. 3, a boiler 11 for waste heat and an electrofilter 64 are connected to the reactor 6 in the flue gas exhaust direction. 0.

In the waste heat boiler 11 formed as a swirl cooler 44. further substantial heat is removed from the flue gas exiting the reactor separator 6. In the electrofilter 12, the flue gas is gently cleaned, whereby the solids present in line 15 are led to line 10 and discharged to a vortex cooler 14.

Whirlpool £ 4. provided with four successively flowing chambers, it is fluidized with ^an acid-containing gas fed through a bran 60. ^The gas ^collects in the housing and is fed through the scoop 2 as a secondary gas to the reactor 6. In the cooling registers, it is effected by means of the gas supplied through the pipe. which optionally contains oxygen, to indirectly cool the solids. The gas exiting the cooling registers 13 is fed to the reactor 6, except for the partial stream of fluidizing gas which is fed through line 8. A separate partial stream is used for pneumatic introduction of the carbon-containing material by means of a blower tube 6.

He did

Using the apparatus of Fig. 1.

Coal with air was combusted using a 1 × 1m and 12m high-altitude combustion reactor (6). The reactor (6) was provided with a cooling surface (60m ²⁾ on all walls. In addition, there were flat perpendicular cooling surfaces of 27 m ² above the pipeline and for the secondary gas. The fuel lance 6 was located 0.2 m above the grate and the secondary gas line 2 was 2.5 m above the grate.

1, t / h of coal having a calorific value of H = 30.0 MJ / kg with a mean grain size of 0.1 mm by means of 150 Nm-air was pneumatically introduced through the lance 2. Grows the reactor was £ fed ⁰⁰⁰ Nm ^ ^/ h conditi ^h uo te ^pl of ^I 3 ⁰⁰ ° C and ^p otrubím 2 da ^LSI CH 4 3 ⁰⁰ Nm ^{P /} h mod ^d uc ^h on straight ^EZ of te ^pl OTE 3 ⁰⁰ ° C. Central ^h US OTA sus ^{t p p} Enzo in free space only ^to rea Toru £ ^p by ^p abrasion ^B im 2 P ^{ro to} undární gas was 300 kg / m, in the space above it was 50 kg / m. The temperature in the entire circulatory system ^was about ⁰ ° C. Zb ^ytky with ^p and ^L s ^{are ck} o ^ e ^ ny in ^dl with ^no network ^for a ^{6-D P and Al,} for ^instance currencies IVa ^d £ back into the reactor. The sub-stream discharged via line 52 was kept large enough to return as much as five times as much residue as there was in the solids reactor per time unit.

Under the given operating conditions, the heat transfer coefficient of 120 N / m-deg was reached. From price ^Number Qty ^BC ivedeného EPLA ^{t 9,} the second 1 ° ⁶ W ^{would be} taken away 5 ^, Q. W ⁶ W ^{for a BE} productions ^y that steam at 60 bars through the cooling surfaces. Heat utilization was 99%, carbon monoxide content in flue gas was less than 0.1%.

Example 2 using the apparatus of Fig. 1.

The coal was burned with oxygen-enriched air. For this purpose, the above-described fluidized-bed reactor 6 was used, with the cooling surface in the upper 22 area of the reactor 6 being increased to 37 m 2. In addition, a 15 m cooling surface was installed in the separator 6 on the walls.

When operating at full load was pneumatically fed 2.7 t / h of coal _with a calorific value H = 30 MJ / kg os ^{class d} e n ^s zrnltosU ^0.1 mm using ^I 3 °° ^P Nm ^{/ h} nu ^ply is 60% of the drawbar . ^{b h} is about em ^alkyl sliko of te 3 ^p ture ⁰⁰ ° C. ^The grate of the reactor ^{d with d} eno weighing ^4,700 Nm ^p / h nu ^ply is ^{60% of the} drawbar. Shah of ^b to ^{y Li} to the heat-te _ 30 ° C and ^p bran ^d m and ^d £ ^l s ⁱ c ^{h 3100} Nm ^ ^/ h · nu ^ply also having ^{a 60%} by Shah ^b · ^j ob. sl k ^{y s} te to the ^pl OTE 3 · ⁰⁰ ° C. Medium density sus Enzo ^P in ^P ros ^t oru ^would la ^p of the ^{t dp} ru ^{running in} m 2 ^p r ^o n ^y sekundártá pl of about 3 to ^{00 g /} rn ^P in Horray area REA ^kt oru about 1. ⁹⁰ kg / m ^P. Te ^p lota throughout both ^H aligns correctly with ^{the syndrome} and it ^was about 85 ⁰ C. ^p · Z evnýc ^{methacrylate h} e ^{d for} the ^d loučenýc ^h in Ovako lu ^No 6 from the exhaust gas to the reactor 1 is returned solids so that reflux was eight times the reactor content was ^{characterized} residue thereinto via line 10th

O

Under these operating conditions a heat transfer coefficient of 290 W / m ' Of ce ew ^{h o f} the amount stv ^s operational status ^BC it ^é te ^pl and ^23.4. 1 ⁰ ® ^{W would} have paid ^18.7 . ^W 10® ^on the production ^{of E} with ^yl é steam at 60 bars through the cooling surfaces.

Due to the reduced power input, the plant should operate at one third of steam production.

No changes to the reactor I at the installed cooling air 4, the second inlet coal sn ^iz ene to ^0,9 t ^{/ h} and ^at the ^ADE in ^both N ^{and P} dip dmýc ^h AC ^and trubty stouž 2 ^ o I ^{00 P} mod Nm ^d uchu. The quantity of fluidizing gas and secondary gas of unchanged quality was reduced to 400 mm ^{P /} h, ^or about ^p and d 2 ^of the ^{'200 P} Nm ^/ h.

Under the mentioned conditions, the solids concentration in the lower space of the reactor 1

3 increase about. to 53 ^{0 kg /} m and ^P in the headspace rea oru ^kt 1 is reduced to about ³⁰ k ^g / m. ^p řestup TE and ^PL is reduced to ^{100 W /} m ² deg.

Thus, the power input could be adjusted by varying the amount of coal supplied and by feeding the fluidizing gas and the secondary gas. The solids content in the whole reactor, and te ^pl J. Oto ⁸⁵⁰ ° ^C * 10 ° C in both ^h o ^s m systomu ziistoty ^{unchanged y N} N o.

Switching to increased power or full load was possible in the shortest possible time.

Example 3

Using the apparatus of Fig. 1.

The fuel oil with air was combusted at elevated pressure. The described fluidized bed reactor 1 was provided with a total cooling area of 132 m &lt; -1 &gt;. Of this, 60 m on the walls of the reactor space 1, 25 m on the separator walls 6 and 47 m were in the free space of the reactor 6 above the secondary gas line. There was sufficient limestone in the reactor as bedding material.

1.5 t / h of fuel oil with a net calorific value of 40.2 MJ / kg with a content of 3.2 wt. open. In addition, 278 · kg / h of limestone containing about 97% by weight of CaCO, with an average grain size of 0.1 to 0.2 mm, were introduced pneumatically as bedding and desulphurizer corresponding to a molar ratio of 1.8 moles per mole of sulfur contained in fuel oil, with 50 Nm ^P air.

^R by ^{TEM was} a malfunction ^of no 1 ⁰ 5 ⁰⁰ Nn ^{P /} ha ^p abrasion ^{is running} m £ ^P ro selkundéir ^ ^p l ^y n ⁷⁰⁰⁰ Nm ^{p /} h of air ot ^L and ^K with ^{a 5 b} ar ^and te ^pl ot ³⁰⁰ ° C. V ^'Both calls ^é m systomu ^was not ^p Lot 85 ⁰ ° C. ^{The solids collection} through line 10 and the solids return line through line 2 corresponded to approximately eight times the solids contained in the reactor 7.

For these operating conditions, being in the reactor space 1 via line 2 below the secondary gas mean suspension density of 300 kg / m and ^P in the reactor space 1 above the conduit 2 for sekumd ^and R m ^d l ^{p y} n of ⁶⁰ kg / лг. Ou ^{S or} N ^{IT l} e Prestop Topla ol ^{To a} 1 ^{50 W /} m ² deg. ^For ERN ce ^ ^{s p} comprises supplying it to ^p Ia MNOZSTOM 1 .1 ^{0 8.6} ® were used ¹¹ ° 4.10® q ^{CR beP} and ^Ry pressure of 0 bar ⁶ by means of cooling surfaces formed tubes.

Fuel utilization was 99%. The carbon monoxide content of the flue gas was below 0.1 vol%, the nitric oxide content was below 100 ppm and 90% desulfurization was achieved.

Example 4

Using the apparatus of Fig. 3.

Coal scrubbers were burned with oxygen-enriched air. The fluidized-bed reactor 1 described in Example 1 was provided with cooling surfaces on the walls of 60 m ^{2 *} , in the upper space of the reactor 1 58 m ² and in the separator of 25 m ² .

Coal scrubbers with an ash content of 67% by weight, 30% by weight of combustible material, 3% by weight of moisture, a mean grain size of 0.08 mm and a net calorific value of 8.4 MJ / kg with a flow of 1000 Nm ^ ^/ h were introduced into the blowing tube X. Ravn ^{P s} with him ^b Shah gas ⁶⁰ vol.% acid-ku te ^pl Oto 45 ^0C. Zavdáno grate ^was about ⁴⁰⁰⁰ Nm @ h selkun ^¹H RN ^gives the ^ply nu straight ^from Shah ^b with ⁶⁰ vol.% Acetic ^phorous u · te ^pl Oto 450 ° C.

Tredny ^{S h t} of Buffer and suspended in the space ^{P dp} otrubím ^yl X b and about ²⁵⁰ Kg ^/ m ^ and ^P ros ^t oru abrasion over ^P X ^B im about. 70 kg / ^m .

Overhead ash removal per unit time was ten times the reactor content the first ^I C ^s The remaining ^part was ^y N ^{and a valyl-abrasion is running} m £ 0th Te ^pl of ^T and throughout ob ^EH b ^s ^ m sys him ^by La, and ^p and ⁸⁵⁰ ° C.

The hot, non-flammable residue carried by line 10 was fed to a vortex cooler 14 which was provided with four chambers and connected cooling registers 11 immersed in individual chambers. ^J and ^K of ^{fluoroborate driver} for ^No. n ^¹H the ^ply nu b ^y lo ^p ou ^zit about ²⁷⁰⁰ Nm ^ ^/ h of gas containing 60 vol.% Acetic ^phorous ua is not ^at m ^é it c ^ and d ^ and ⁵⁰⁰⁰ nm ^{J /} h ^ply nu same ^condition in both ^cases, ADEC ^h ohWtýc ^h at 45 ° ^C and close ^Aad ěnýc ^HD of rea ^kt oru 1 I ^to about selcun ^ RRA ^p l ^y n and ^FL at ^{the driver} for ^{N NU ply} n, optionally as transport gas.

^RL him Avy unnecessary ^to b n ^{yl characterized as} CZ Vol ^{IR eh} also cools the TE ^{14 PR} and ^{PL E} 15 ot ⁰ ° C. ^From AT ^E c ^h a reward ^greater than ^{p to} b ^{y d z} axis lo eno product ^{i l} te e ^BC ESTs ^p u ^t EPLA 2 ^{00 W /} m? deg. ^Of ce em pMvedenéto Quantity ^{lk s p} la te ^22.6. ®W ^{was 10} s ^s u ^{ITO 16.6.} W ^{LOS for the} production of the ^{p y y} ares rt ^l battery ⁶⁰ ares ^{b p} dip cooling surfaces.

SUBJECT OF THE INVENTION

Claims (12)

cooling surfaces. SUBJECT OF THE INVENTION 1. A method of combusting carbonaceous materials in a fluidized bed, re-introducing entrained solids into a fluidized bed and dissipating combustion heat through cooling surfaces, characterized in that: - the combustion is carried out with oxygen-containing gases supplied in two partial streams at different heights; wherein at least one stream is fed as a secondary gas to one or more planes one above the other, the volume ratio of fluidizing gas to secondary gas is adjusted in the range between 1:20 to 2: 1, formed above the secondary gas supply by adjusting the secondary gas velocity; the ratio of fluidizing gas and ^to un ^can RN ^¹H the ^ply Nu ^{IRI and} TRS ^t va axis ^t's Publications ^and density of ^a suspension of ¹ 5 and ^from the ¹⁰⁰ kg / m \ NEJM ^{e d p} o ^d substantial part of heat of combustion is dissipated through cooling surfaces arranged above the secondary gas supply in the free space of the reactor, the bulk of the material The carbon-containing reactor is introduced into the reactor free space under a secondary gas supply, practically free of built-up installations, and the solids are removed from the circulating system formed from the fluidized bed reactor, the trap and the return line. 2. A process according to claim 1, characterized in that a partial stream of oxygen-containing gases is fed to the fluidized bed combustion reactor as a fluidizing gas. 3. A method according to items 1 and 2, characterized in that:. The secondary gas is introduced at the highest point at a height of up to 30% of the total height of the fluidized bed reactor, at least 1 m above the fluidizing gas supply. 4. A method according to any one of claims 1 to 3, characterized in that the combustion heat is removed by cooling surfaces arranged on the walls of the fluidized bed reactor. Method according to one of Claims 1 to 4, characterized in that the cooling is carried out by means of cooling surfaces consisting of tubes parallel to the flow direction of the slurry of gas and solids and connected by means of bridges. . 6. A process as claimed in any one of claims 1 to 5, characterized in that the combustion is effected into residues. The fuel-rich residues are cooled in a vortex cooler, provided, in particular, with a plurality of chambers flowing in succession, during heating by a gas-fired fluidized bed reactor as a fluidizing gas and / or a secondary gas. 7. A method according to any one of claims 1 to 6, characterized in that:. the flue gases combusted in the fluidized bed reactor are introduced as fluidizing gas into the vortex cooler and cooled by heat exchange with the refrigerant flowing in the cooling surfaces. 8. A process as claimed in any one of claims 1 to 7, wherein the combustion process is carried out with the introduction of a fine-grained desulphurizer. 9. A method according to any one of claims 1 to 8, wherein the combustion process is carried out with oxygen-enriched air. 10. The method according to items 1, in particular up to 2.0 MPa. 1 to 9, characterized in that the combustion process is carried out under pressure 11. A method according to any one of claims 1 to 10, wherein the combustion power is controlled by a suppens density in the space formed above the secondary gas inlet of the fluidized bed reactor. 12. The method of claim 11, wherein the combustion power for reduced power is controlled by reducing the density of the slurry in the space formed above the secondary gas inlet of the fluidized bed reactor.