CS239582B1 - Steam Boiler Steam Boiler - Google Patents

Abstract

The invention relates to a steam superheater of a fluidized bed steam boiler, in which the arrangement of individual stages of the steam superheater immersed in the fluidized bed is solved in order to ensure the uniformity of the temperature of the fluidized bed over its entire cross-section. The essence of the invention lies in the fact that groups of superheaters in fluidized beds consist of superheaters (I, II, III, ...), whose coils, covering bundles of coils are immersed in the fluidized bed in a regularly repeated order or in such a way that all coils of the superheaters (I, II, III, ... etc.) are fired in one bundle of coils.

Description

239582

BACKGROUND OF THE INVENTION The present invention relates to a steam superheater, whereby the distribution of heating surface heaters at the focal points of a steam boiler is effected by fluidized combustion in order to ensure an optimal cooling of the fluidized bed. At present, there is an unprecedented interest in using fluid technology to fuse different types of fuels. Indeed, the fluidized bed combustion also allows the use of non-bleaching fuels with a low calorific value for heating and electricity purposes, while maintaining the conditions of so-called "clean combustion", without the consequent disruption of ecological rela- tions in the given landscape area. One of the conditions for ensuring "clean combustion" is also to ensure proper desulfurization. a process which takes place in a fluidized bed in the presence of added suitable additives (limestone, dolomite and the like, binding harmful components of the chemical reaction), thereby avoiding the formation of undesirable sulfur oxides polluting the country's air. However, it should be noted that The optimal desulphurisation process in the fluidized bed combustion is absolutely necessary to maintain the correct combustion temperature in the narrowest possible tolerance range. types of heat exchanger surfaces are also directly influencing the device of constant optimum combustion temperature of the given fuel. In the case of small-scale outbreaks, the cooling of the fluidized bed is reliably ensured by the evaporator tubes.

Problems with maintaining a constant combustion temperature are generated in the power and correspondingly larger fluidized beds in which the heat-released vofluid layer is removed by the tube superheater system. The tubular superheater steam system immersed in the fluidized bed consists of multiple portions providing the working medium to the nominal parameters. However, this does not result in uniform heat dissipation in the fluidized bed with subsequent formation of working at different combustion temperatures exceeding frequently permitted temperature tolerances. In this solution, when the individual steam superheater parts are submerged in the fluidized bed in each focal point, there is a demand for a very complex control of the combustion process in each focal point, consisting in particular of regulating the supply of fuel, primary and secondary air, such as and additive feed. 4

The essence of the steam boiler superheater of the fluidized bed combustion of the feed pipe, the regulation of the inlet and outlet chambers, the snakes and the serpentine bundles, is that the superheater groups in the fluid foci consist of superheaters whose snakes , coated with bundles of snakes, the fluidized bed submerged in a regular repetition or so that all the snake heaters are replaced in one snakes. All superheaters have an inlet and an outlet chamber, while control valves are located in the supply line branches. The advantages of such arrangements of superheaters forming a group of superheaters located in one or more fluidized beds are mainly due to the fact that the removal of heat from the fluidized bed is as uniform as possible to the width of the fluidized bed width, thereby achieving the highest desulphurisation effect, limestone consumption is reduced and overall boiler efficiency is increased.

1 is a schematic cross-sectional view of a fluidized-bed steam boiler in FIG. 1, in section A-A, and FIG. 2 in section B-B, and in section C-C, the same boiler side view. Fig. 3 is a detail of the superheater group locations with inlet pipes. Figs. 4, 5, 6, 7, 12, 14 show examples of the placement of the pre-heaters in front of each other, in Figs. 8, 9, 10, 11, 13, 15 in one embodiment. The saturated steam produced in the boiler body 2 is conveyed through the transfer tubes into a distribution chamber 3 from which the transfer tubes 4 reach the convection pre-heater 5 located in the first combustion draft 6. From the convection heater fi, two or four branches 7 of the steam pipeline in which the regulating fittings 8 are located, steam is transferred to a group of superheaters 1 located in two fluid foci 9 immersed in the fluidized bed 10.

The superheaters 1 consist of a plurality of portions of superheaters I, II, III, as well as superheaters IV, V, VI. These are connected to each other by switching pipes 11, in which the auxiliary injections 12, or in particular the injectors 13 of the superheated steam control system can be placed. Each of the superheaters I, II, III, IV, V, VI, it consists of inlet chambers 14, snakes 15, coil bundles 16 and outlet chambers 17, from which superheated steam is discharged through the outlet pipe 18 to consumers. Snakes 15, or snake bundles 16 pre-sinners. I, II, III, .. are in a fluidized bed 10 submerged in a regular repeating order, for example 1, 2, 3; 1, 2, 3 ... 1, 4, 2, 3; 1,4,2,3, ... or by replacing snakes 14 of all pre-rinsers I, II, III in one trial.

Claims (4)

23 as 82 OBJECT Fluid-fired steam boiler steam superheater consisting of supply line branches, control valves, inlet and outlet chambers, serpentine snakes and coils, characterized in that the superheater groups (1) in fluidized-bed furnaces (9) ) consist of superheaters (I, II, III, ...), whose snakes (15) coated spacers (16) are immersed in the fluidized bed (10) in a regular repetition or so that in one of the dragonflies snakes (16) will take over all snakes (15) of superhighters (I, II, III, ...). VYNALEZU 2. A steam superheater according to claim 1, wherein the superheater group (1) is provided with a convection superheater (5) connected by supply line branches (7) in which control valves (8) are located. . 3. A steam superheater according to claim 1, wherein all superheaters (I, II, III, ...) in both fluid foci (9) have an inlet chamber (14) and an outlet chamber (17). 4 sheets of drawings