SE434883B - SET TO OPERATE A COMBINED GAS ANTURBIN INSTALLATION AND COMBINED GAS ANTURBIN INSTALLATION FOR USE OF THE SET - Google Patents

Description

Eoov214 ~'s sensors which sense the temperature in the bed or of the gas which leaves the bed at substantially the same temperature as the prevailing bed. Control devices in the system regulate the water supply in dependence on a signal coming from the sensor or sensors.

The invention also relates to the method of operating and regulating the plant. the temperature of the bed with increased fuel supply at temperature below the so-called laying temperature To by cooling the bed by directly introducing water into the bed. The fuel supply increases with increased air supply when the ambient temperature drops. in such a way that the excess air factor 1 is kept substantially constant. the lowest. allowed., Oh min. The corrosion richness of the steam generation tubes in the fluidized bed 'determines the value of Ämin.

JL, G “o IBG s available air volume (kg / s) no = air volume in kg needed to burn 1 kg fuel 3 = fuel quantity (kg / s) Minimum permissible value min is tested and depends on combustion chamber design, fuel, bed material, etc. Usually Q, à is 1.5.

The water can be supplied to the fluidized bed together with fuel. Coal peat powder can be suspended in water into a so-called slurry and introduced into the fluidized bed through nozzles provided for this purpose.

The invention describes: xäzmare with reference to the accompanying figures. Fig. 1 schematically shows a ventilation system, Fig. 2 a bed included in the power plant, Fig. 3 a bar graph of bed temperature, Fig. 4 a diagram of the relationship between the excess air and the ambient temperature when the invention is not applied and Fig. The relationship between ambient temperature and removable. the effect.

In the figures. 1 and 2, 1 denotes a pressure vessel enclosing a combustion chamber 2 with a fluidized bed 3. In it. there is a pipe loop. 4 which is surrounded by the bed material.

The gas turbine part plants contain a high-pressure turbine 6 which drives a high-pressure compressor 5 and a low-pressure turbine 7 connected in series with a turbine which drives a low-pressure compressor 8. A starter motor 10 is connected to the high-pressure compressor. In the line 11 between the low-pressure compressor 8 and the high-pressure compressor 5 there is an intermediate generator 12. Furthermore, there is a power turbine 13, which drives a generator 19.

The high-pressure compressor 5 is connected to the pressure nozzle 1 with a line 14. The burner 2 is on. its outlet side is connected to a high-pressure turbine 6 by a line 15. Between the lines 14 and 15 there is a line 16 with a valve 17, through which compressor air can be mixed with combustion gases in order to regulate the power of the plant. The high pressure turbine 6 and the low pressure turbine 7 are connected to each other through the line 18. The low pressure turbine 7 is connected to the inlet turbine 15 by a line 20. The steam turbine part contains a steam turbine 21 which drives a generator 22. Condensate from the turbine 21 condenser 22 is pumped by the feed water pump 25 through the line 24 to the feed water pre-heater 25 and was then laid through the line 26 to the pipe loop 4 in the combustion chamber 2. Steam is generated here. which is fed to the turbine 21 through the line 27. The exhaust gases from the power turbine 15 are led to the feed water for the heater 2§ through the line 28.

The combustion chamber 2 divides the pressure vessel 1 into two separate chambers 30 and 31. Compressed air from the high-pressure compressor is supplied to the lower chamber 50 and is blown in through the muzzstyok 32 in the combustion chamber 2 and keeps the bed material in the bed 5 in a fluidized state. Fuel is supplied through the line 53. A pressurized water tank 54 stands through a line 35 with a control valve 56 in connection with nozzles 57 Through which water can be sprayed directly into the bed 5 and thereby on its evaporation cool the bed 3. Water injection regulated depending on the bed temperatures. A sensor 58 senses the temperature and a signal is applied to the controller 40 * via the line 41. Depending on this signal, the device 40 controls the valve 56 and thus the amount of water supplied to the bed. The sensor 58 may be located in or above the bed 5, since the combustion gases leaving the bed 3 have approximately the same temperature as this.

High efficiency in a combined gas-vapor cycle accelerator of the type described with combustion in a fluidized bed at elevated pressure, 10-16 bar, is a reason for the great interest in this. A total system efficiency of over 40% can be achieved. Another advantage is that combustion can take place at low temperature, 800-850 ° C, so. that melt ash can be avoided. Particles that accompany combustion gases from the bed are "dry" and therefore do not have a tendency to stick to a treatment plant, for example of the oyclone type. For gas turbines, sufficiently efficient purification can be achieved and reduce the risk of deposits. turbine blades are available.

A further advantage is that sulfur in the fuel can react "dry" with a suitably selected bed material, eg dolomite, and thereby is absorbed by it to form gypsum and is removed together with ash from the fuel and spent bed material. Dispersion of sulfur compounds with the flue gases. can thus be prevented 10 15 20 25 35 soo? 21a ~ s 4 A particularly great advantage is that coal can be burned completely at so. low temperature as 800 = 850 ° C., that the temperature in the fluidized bed must be kept within tight. limits involve certain problems which, however, can be eliminated by the invention, Fig; 5 illustrates this. The temperature of the bed 3 should be kept within the interval A43. Within the interval B-C, combustion can be maintained but reduces the absorption of sulfur and turbine power and decreases the degree of heating. above level A, ash melts, which can form lumps that clog air and fuel nozzles or that can form droplets that accompany the combustion gases and settle in the cleaner and on. hmbinskovlæ. Because the ambient temperature drops below the so-called lay-out temperature '29 and the density of the air and thus the mass flow through the compressors increases, 25% the oxygen that is available for combustion. This. Oxygen can only be used to a very small extent for the combustion of an increased amount of fuel, unless cooling of the bed can be increased. The cycle effect of the anxiety loop is largely constant and increased combustion causes the temperature of the bed to rise rapidly to an impermissible level. The excess air factor rises as illustrated in row 4. The excess air factor Ä has been deposited on the vertical axis and the external air point T. To = + 50 ° C. At the laying temperature ratio Ä = 1.5. at Ä below 1.5, the atmosphere in the bed becomes reducing and corrosion is obtained. tubes in the bed. Å = 1.5 is thus it. lowest. excess air vector that can be allowed. Without increased cooling, the supply of fuel cannot be increased in proportion to the amount of oxygen available at temperatures below To. The value of Ä rises as the sloping solid line A63 shows. Reduced power is obtained with both the gas turbine part and the steam turbine part.

Fig. 5 shows the delivered power of the power supply, ie the power emitted by the steam turbine 21 and the power turbine 13 of the gas turbine part, the steam turbine 21 emits a substantially constant power between -3000 and + 30 ° C. Thereafter, the effect decreases with increasing ambient temperature. See curve ABC. The power gas turbine 15 emits an effect which is the difference between the curves. DEF and ABC in case the invention is not applied in the operation of the plant. When the ambient temperature drops below the ambient temperature so -_ ~ ~ + 30 ° C, the effect rises slightly through the small air flow. over TO Junker effect on. Due to the fact that a reduced amount of oxygen is available for combustion and the fuel supply must be reduced so that Å does not junk. below the permissible value. In the case where the invention is applied in the operation of the coil, the ln-sfthirbine emits an effect which is the difference between the quarks GEF and ABC. The additional effect that can be obtained by applying the invention is the difference between the parts GE and DE. This additional effect is achieved

Claims (4)

eoov214 ~ zt by adding water to the bed 5 at its predecessorxxgg cools the bed and enables 'increased fuel supply at unchanged' bedtænpaIG-tW. The increased mass flow through the * steering wheel and fuel supply and the increased energy supply through increased combustion give the increased output power. PÅTENTEAV A method of operating a combined gas-steam turbine plant in which gas for the gas turbine and steam for the steam turbine is generated in a) common combustion chamber with combustion in a fluidized bed, and in which b one is used for the gas turbine during operation at the so-called extraction temperature , so. that the right amount of gas at the selected outlet mixing temperature gives full power utilization of the turbine wax, is characterized by the fact that the excess air falcon at decreasing ambient temperature and consequent increasing air tightness and increasing air flow is regulated by increasing the fuel and at the same time the bed temperature is regulated by injecting water or water vapor into the bed (3), so that unauthorized agitation of the bed temperature is prevented due to the increased fuel supply. 2. A method according to claim 1, characterized in that water is supplied to such a large number that the hoisting phase (A) and the bath temperature are maintained at a substantially unchanged level with increased fuel supply. 3. 5. A method according to claim 1, characterized in that water supplied to the net (5) contains fuel suspended in the water. A combined gas-steam engine plant for using the method according to claim 1, in which gas for a gas turbine (13) and steam for a steam turbine (21) is generated in a common well (1) with combustion of the fuel in a fluidized bed (3). ), in which plant b a (1) is adapted to the gas turbine (15) so. that it gives the required amount of gas for the gas turbine (15) for a specified power at a certain temperature, usually + 50 ° G. characterized in that the plant contains a sensor ('58) for determining the bed temperature, a sigmal treatment means (42) which compares the actual value of the temperature with the setpoint and when the setpoint is exceeded via. a regulator (40) provides for the injection of water or water vapor into the bed (3) depending on the temperature difference for lowering the bed temperature.