DE3103721A1 - High-temperature gasifier - Google Patents

Abstract

A water-cooled high-temperature gasifier for gasifying coal, wood and other fossil feedstock comprises water-cooled reactor walls with additional cylindrical tubular coils which are arranged in front of the walls and have water flowing through them and which are held against the reactor wall by cell-forming comb-shaped metal sheets. As a result of the cylindrical tubular coils with the comb-shaped sheets which completely or partially hold the slag layer which forms during gasification against the reactor wall even at very high temperature, such a gasification reactor is suitable for protecting the reactor wall against excessive temperatures. The cylindrical tubular coils can be rapidly replaced at certain intervals as a cheap part which is subject to wear.

Description

High-temperature carburetor

The invention relates to a water-cooled high-temperature carburetor for coal and other fossil fuels, in particular an entrained flow or Sleep bath generator with liquid or doughy sleep.

When gasifying soles, wood or other fossil fuels a raw gas is obtained with the help of oxygen and water vapor. The composition of the raw gas depends on the type of feedstock to be gasified, but also on the type and amount of the supplied water vapor and oxygen or the supplied Air.

The optimal reactor temperature (reaction temperature) can also, among other things depend on the Fartoren - ash / flake type - admixtures to be gassed in the Feedstock - heavy hydrocarbons - slag flow behavior at the reactor outlet - partial load behavior of the reactor.

Entrained-flow carburetors can - as high-temperature carburettors - operating temperatures from 1,500-2,800 C.

In terms of heat, the radiation intensity of the gasifying solids becomes - Carbon particles equated with that of a "black body" (approx. Value).

The reactor design must take these operating conditions into account.

Reactor demonstrations, which are supposed to meet these extreme conditions, generally consist of a water-cooled or boiling-water-cooled jacket with a insulating layer in front of it. This insulating layer exists in most of them Cases from a high-temperature-resistant brick lining or rammed earth.

In the medium temperature range of 1,100 - 1,300 OC, the insulating, ceramic layer usually from a more or less thick film of slag coated, which - with appropriate strength - additional insulating effect Has.

At the same time, the slag fur protects the masonry behind it as well as the cooling elements through which water flows from erosion and corrosion in reducing atmosphere and in the presence of alkalis and gas companions, how H2S, Cl2, HC1, H2, CO, C02, N2 etc.

The cooling elements through which water flows - or should for reasons economic efficiency - be carried out in the form of natural circulation evaporative cooling.

However, experience with such systems has shown that the The above mean temperature values up to 1,360 ° C cannot be maintained in practical operation but that temperature peaks of up to 2,800 (e.g. due to inhomogeneous coal flow, due to uneven distribution of coal, high ash melt values, etc.) short-term and be driven in the medium term.

At these high temperatures there is usually a total Destruction of the insulating ceramic lining in front of the cooling jacket.

The insulation layer is then destroyed - due to increased Heat radiation to the cold reactor wall - an increased use of oxygen, e.g. to ensure the schacken runoff temperature.

Temperature-related higher O2 use in the aforementioned sense means but also migration, i.e. ~ deterioration in gas quality and yield.

The water or boiling water which is now exposed to free heat radiation The cooling system can now also be subject to the corrosive attack and be damaged. Breakdowns with long downtimes cannot be ruled out.

The invention is based on the task of creating a system soft prevents the total destruction of the masonry and at least partially Existence of the slag protection film secures.-According to the invention, this is achieved by a special procedure for the arrangement and construction of cooling tubes, which the reactor space form, achieved.

This is done in front of the reactor walls exposed to cooling or boiling water (Cooling wall construction) an additional cylinder pipe spiral through which water or boiling water flows laid with only a slight or 0 slope.

The scope of this measure is usually reduced to the actual one Reactor room with the highest temperature peaks to be expected.

The attachment, i.e. holding of this cylinder tube spiral, takes place by so-called comb plates (welding fins), which are centered or slightly eccentric are welded one behind the other on the outer circumference of the cylinder tube.

This means that these comb plates are used as fastening and holding elements in the radiation shadow of the reactor room ..

There are no critical heat flux densities on these comb and holding irons expected.

Pipe wall, comb plate and cylindrical pipe spiral now form cells, which are filled with ceramic ramming material and - in the event of destruction or dissolution this - be substituted by coal slag.

Thinner coal slag overflows the cylinder tubes - the filling underlying cells.

This slag flow mechanism works on the cooled reactor wall always and regenerating a minimum wall coverage through draining and cell-filling Slag.

The distance between the cylinder tubes (pitch size) is determined ultimately the desired degree of secured slag cover on the reactor wall.

It goes without saying that the amount of slag produced and the slag viscosity are also included further criteria for the thickness of the resulting slag pelt.

According to a further feature of the invention, the Eammbleche with certain gaps from each other welded to the cylinder tube spiral. Of the The distance between the individual Eammblechen is dimensioned so large that -'bei Heat flux densities of 800,000 kcal / m2h and higher - part of the slag by the resulting slits can flow into the next cell below.

According to the invention, the comb plates are offset against one another - welded to the cylinder tube spiral - that the slots are arranged alternately with one another and the slag thus cascades downwards.

The possibility of covering the cooled reactor wall with slag is thus maximized.

The cylindrical tube spiral holding the heat exchange surface of the slag is small, - the heat exchange capacity is correspondingly low.

Since the construction form of the cylinder tube spiral described above is also simple, surprisingly result - in addition to the above according to the invention The desired retained slag layer still has the following additional system advantages: - The risk of corrosion damage to the reactor is eliminated, the same applies to possible risk of erosion.

- The reactor can be operated by means of evaporative cooling - in natural circulation will. The system becomes more economical due to more cost-effective construction, elimination the circulation pumps and circulation pump line.

- The heat dissipation from the reactor is lower, the use of oxygen occurs more optimally.

- The simple cylinder tube spiral can be made of high-alloy, corrosion-resistant Material hergestell.t, whereby the material for this boiler technical - external to be seen - cooling coil is not necessarily below the one that requires a permit for steam boiler construction Materials must fall.

- Instead of high-alloy steels, standard materials used in steam boiler construction can be used are used, which are corrimuniert.

- The cylinder tube spiral can be extracted from the steam / water circuit (with separate cooling) '.

- The cylinder tube spiral can in the present simple design are viewed as wearing parts, with the possibility of inexpensive replacement, for revision work.

In the drawings - Fig. 1 - 3 - is the subject of the invention shown.

Fig. 1: Process and integration of the cylinder tube spiral system in Gasification reactor.

Fig. 2: Arrangement and mounting of the cylinder tube spiral with illustration of the slag flow.

Fig. 3: Detailed drawing of the pipe arrangement and connection with representation the comb plates.

In Fig. 1, the integration of the system cylinder tube spiral 10 is in Gasification reactor shown. The cooling walls 1 enclose the interior of the reactor 2.

The water is supplied by natural circulation through the downpipes 7; the steam-water mixture is transferred to the evaporation drum 5 through the overflow tube 6 fed.

In the example shown, the coil is for the Slag holder included in the main cooling circuit of the reactor.

A recirculation pump 8 conveys a partial flow of the circulating water via a heat exchanger 9 into the cylinder tube coil 10; the heated water will fed back to the evaporation drum 5 via line 11.

Through the heat exchanger 9, the cooling water can be approx.

30 - 40 tJ above the corresponding boiling point. By means of a thermometer - installed in the line 11 - the water can be heated be controlled: This water heating can be used as indicator serve for the respectively built-up slag pelt. After the respective measuring processes, (e.g. once a week, or after load changes) the heat exchanger 9 be switched off again. The gasification burner 3 was shown schematically, likewise the slag outlet (4).

Fig. 2 shows the arrangement and mounting of the cylinder tube spiral 1.0 showing the slag flow. The reactor space 2 is welded gas-tight Pipe walls formed with an "outer" insulation 13 behind them, consisting made of glass wool mats. The cylinder tube 10 forms with the membrane tube wall 1 the o.a. Cells 14 which are filled by the slag film.

In Fig. 3 is shown the detailed drawing of the drilling assembly and - Connection with the comb plates: In front of the reactor wall 1, formed from gas-tight with one another welded tubes, the cylinder tube 10, which in turn by comb plates 15 is welded to the wall. You comb plate O15 with gaps 16, 17 to the Cylinder tube welded and form the openings described if the size is appropriate for the slag passage.

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Claims (12)

Claims 1) High temperature carburetor for throat, wood or other fossil feedstocks, water-cooled; the reactor space, consisting of gas-tight with each other welded pipe walls d a d u r k h e k e n n e n e c h n e t that before the water-cooled Reactor walls (1) a cylinder pipe coil (10) through which water flows. 2) high-temperature carburetor according to claim 1, d a d u r c.h g e k e It is noted that the cylinder tube coil (10) with or without Incline is mounted. 3) high temperature carburetor according to claim 1 and 2 d a d u r c h g It is not noted that the cylinder tube spiral (10) is formed with cells Comb plates (15) is mounted on the reactor wall (1). 4) high-temperature carburetor according to claim 1 - -3 d a d u r c h g e it is not shown that the comb plates (15) are attached to the cylinder tube spiral (10) be welded that this with the reactor wall (1) - consisting of. gastight with each other welded pipes - cells (14) form. 53 high-temperature carburetor according to claim 1 - 4 d a d. u r c h g e it is not indicated that the comb plates (15) are spaced accordingly the cylinder tube spiral (10) are welded, in such a way that these slag passage slots (16, 17) form. 6) High-temperature carburetor according to claim 1 - 5 d a d u r c h g e k It is noted that the slag passage slots (16, 17) at the respective one below the other arranged cylinder pipe coils (10) are welded offset and form a slag flow cascade. 7) high temperature carburetor according to claim 1 - 6 d a d u r c h g e k e n n n z e i c h n e t that the cylinder tube spiral ('10) 'for the purpose of simpler assembly and disassembly from cylinder segments with individual water passages is formed. 8) High-temperature carburetor according to claim 1 - 7 d a d u r c h g e It is not possible to say that the cylinder tube spiral (10) is formed from partial segments overlapping in the area of the pipe bends, i.e. arranged in a cascade. 9) high temperature carburetor according to claim 1 - 8 d a d u r c h ge.k It is noted that the comb plates (15) only with the cylinder tube spiral (10) are welded and attached to detachable connectors on the pipe wall (1) can. 10) high temperature carburetor according to claim 1 - 9 d a d u r c h g e it is not indicated that between the circulation pump (8) and the cylinder spiral (10) a heat exchanger (9) is connected. 11) high-temperature carburetor according to claim 1 - 10 d a d u r c h g e It is not indicated that the cylinder tube spiral (10) enters the reactor cooling circuit is involved. 12) high temperature carburetor according to claim 1-11 d a d u r c h g It is not noted that the cylinder tube spiral (10) does not enter the reactor cooling circuit integrated, but connected to a separate external heat exchanger is.