JPH0517162B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an apparatus for recovering the energy of gas generated from a catalyst regeneration tower in a plant for fluid catalytic cracking of crude oil using a catalyst, by generating electricity or the like.

A typical prior art is shown in FIG.
In order to perform fluid catalytic cracking of crude oil, crude oil is supplied from a pump 1 to a reaction tower 3 via a riser 2.
Fluid catalytic cracking of the crude oil is carried out in the reaction column 3, where it is decarburized, and the gas from the reaction column 3 is sent through a pipe 4 to the next main distillation column to obtain high quality gasoline.
A catalyst made of alumina or the like to which carbon has been attached due to the reaction in the reaction tower 3 is sent to a regeneration tower 6 through a pipe 5. Air is sent to the regeneration tower 6 via a pipe 9 from a blower 8 driven by a steam turbine 7 or the like. Therefore, in the regeneration tower 6, the carbon adhering to the catalyst is burned and the catalyst is reactivated. The activated catalyst is transferred from the pipe 5a to the riser 2.
supplied to

Generated gas containing a large amount of carbon monoxide from the regeneration tower 6 is discharged from the top of the regeneration tower 6 through a pipe 10, the catalyst is collected in a cyclone dust collector 11, and collected in a hopper 11a. . Cyclone dust collector 11
The gas generated after being collected in the pipe 12
From there, it passes through a slide valve 13 that controls the flow rate, passes through a multiple orifice 14, and then enters a 2-port slide valve 15.
The water is supplied from the boiler 16 to the cooling pot 17. The generated gas containing a large amount of carbon monoxide is combusted in the boiler 16, and the combustion gas is supplied to a chimney 19 through a pipe 18. The generated gas, which is switched at the two-port slide valve 15, is led to the cooling pot 17 and then to the chimney 19 through the pipe 20, where it is dissipated.

Problems to be Solved by the Invention In the prior art as shown in FIG. energy is recovered. However, boiler 16
The generated gas supplied to the regeneration tower 6 suffers throttling loss in the slide valve 13 and the heat recovery efficiency of the steam process including the boiler 16 is low, so that the energy of the generated gas from the regeneration tower 6 is not sufficiently recovered. It's hard to say.

An object of the present invention is to provide an energy recovery device for gas generated from a regeneration tower in a fluid catalytic cracking plant, by which the energy of gas generated from the regeneration tower can be sufficiently recovered.

Means for Solving the Problems The present invention performs fluid catalytic cracking of crude oil using a catalyst, and guides generated gas from a regeneration tower to a combined cycle facility for regenerating the catalyst, and in this combined cycle facility, the above-mentioned steps are carried out. The generated gas is pressurized in a combustion compressor and combusted in a combustor. The combustion gas from this combustor drives a gas turbine. The exhaust gas from the gas turbine is supplied to an exhaust heat recovery boiler to generate steam. This is an energy recovery device for gas generated from a fluidized catalytic separation device regeneration tower, characterized in that a steam turbine is driven by steam.

In a preferred embodiment, a fuel compressor is driven by power from at least one of the gas turbine and the steam turbine.

The present invention also provides fluid catalytic cracking of crude oil using a catalyst, and the generated gas from a regeneration tower for regenerating the catalyst is lowered in pressure and temperature by an expansion turbine, and then introduced into a combined cycle facility. In cycle equipment, the generated gas is pressurized by a fuel compressor and combusted in a combustor, the combustion gas from the combustor is supplied to a gas turbine to drive it, and the exhaust gas from the gas turbine is sent to an exhaust heat recovery boiler. supply and generate steam,
This is an energy recovery device for gas generated from a fluidized catalytic cracker regeneration tower, which is characterized in that a steam turbine is driven by this steam.

Effect According to the present invention, the gas generated from the regeneration tower is lowered in pressure and temperature by the expansion turbine, further lowered in temperature by the heat exchanger, and then led to the combined cycle equipment. The pressure energy possessed by the generated gas is recovered as electric power or motive power, and is then led to a combined cycle facility where it is recovered as power generation or motive power using a gas turbine and steam turbine, making it possible to use the energy possessed by the generated gas with high efficiency. It becomes possible to collect it. In addition, the fuel compressor of the combined cycle equipment that follows this expansion turbine is equipped with an expansion turbine and a heat exchanger.
Since the gas can be supplied at a lower temperature, the pressure in the fuel compressor can be increased easily and efficiently.

Embodiment FIG. 1 is a block diagram of an embodiment of the present invention. Components that are the same as those in FIG. 5 described above are given the same reference numerals. In order to perform fluid catalytic cracking of crude oil, the crude oil is passed from pump 1 to riser 2 to reaction column 3.
is supplied to Fluid catalytic cracking of the crude oil is carried out in the reaction tower 3, where it is decarburized, and the gas from the reaction tower 3 is sent through a pipe 4 to the next main distillation tower to obtain high quality gasoline. A catalyst made of alumina or the like to which carbon has been attached due to the reaction in the reaction tower 3 is passed through the pipe 5.
from there to the regeneration tower 6. Air is sent to the regeneration tower 6 from a blower 8 driven by a steam turbine 7 via a pipe 9. Therefore, in the regeneration tower 6, the carbon adhering to the catalyst is burned and the catalyst is reactivated. The activated catalyst is supplied to the riser 2 through the pipe 5a.

Generated gas containing a large amount of carbon monoxide from the regeneration tower 6 is guided from the regeneration tower 6 to a pipe 12 via a pipe 10 and a cyclone precipitator 11, and from the pipe 30 to an expansion turbine equipment 31. It is then supplied to the combined cycle equipment 32. In the expansion turbine equipment 31 , generated gas from the pipe line 30 is guided to the expansion turbine 34 through the regulating valve 33 .
A bias pipe line 35 is connected upstream of the governor valve 33 and downstream of the expansion turbine 34 . A bypass valve 36 that opens and closes is interposed in the bypass pipe line 35 . In this way, the generated gas from the line 30 passes through the expansion turbine 34, thereby reducing its pressure and temperature. A generator 37 is driven by the power of the expansion turbine 34 .

On the other hand, excess gas that cannot be absorbed by the expansion turbine equipment 31 is passed from the pipe line 12 through the slide valve 13 that controls the flow rate, passes through the multiple orifice 14, and is transferred from the two-port slide valve 15 to the cooling pot 17.
supplied to The generated gas is led to a cooling pot 17 and then to a chimney 19 through a pipe 20 to be dissipated.

Further, generated gas from the expansion turbine 34 or from the bypass line 35 via the lines 38, 39, and 40 is supplied to the combined cycle equipment 32 via the heat exchanger 41. In the conduit 39,
A gas holder 42 is connected. The combined cycle equipment 32 basically consists of a fuel compressor device 5
0, a gas turbine device 60, an exhaust heat recovery boiler device 70, and a steam turbine device 80. In the fuel compressor device 50 , the generated gas whose temperature has been lowered in the heat exchanger 41 is guided from a pipe 51 to a low pressure compressor 52 , further via an intercooler 53 to a high pressure compressor 54 . The low pressure compressor 52 and the high pressure compressor 54 each have a surge prevention valve 5.
5, 56 and variable stator vanes 57, 58, and is normally controlled by a pressure adjustment mechanism 59 to maintain the discharge pressure Pc of the high pressure compressor 54 at a predetermined value.

The generated gas from the fuel compressor device 50 is supplied to the combustor 62 from the conduit 110 via the gas fuel control valve 61 of the gas turbine device 60 . The combustor 62 is also supplied with liquid fuel from a liquid fuel control valve 63 via a pipe 64 . Liquid fuel from conduit 64 is used during normal startup and auxiliary combustion. In addition to the gas or liquid fuel, air from the intake pipe 65 is supplied to the combustor 62 by an air compressor 66.
Combustion air compressed and pressurized is supplied. The combustion gas combusted in the combustor 62 is guided to a gas turbine 67 and converted into rotational force, thereby driving the gas turbine device 60.

Exhaust gas from the gas turbine device 60 is passed through the pipe 6
8 to the damper 7 in the exhaust heat recovery boiler device 70
1 and the boiler 73. Exhaust gas from the boiler 73 and excess exhaust gas passing from the pipe line 68 to the damper 72 and the pipe line 95 are dissipated from the chimney 96.

The high-pressure steam generated in the boiler 73 is supplied from a pipe 74 to a steam turbine device 80 via a pipe 113, passes through a speed regulating valve 81, rotates a steam turbine 82, generates power, and connects a condenser 8.
It is discharged to 3.

On the other hand, excess steam that has not been absorbed into the steam turbine device 80 is transferred from the pipe 74 to the flow control valve 111.
via line 112 to the steam consumer.

Furthermore, the condenser 83 of the steam turbine device 80
The steam discharged is cooled by a condenser 83, and the condensed water is sent under pressure by a water supply pump 115 through a pipe and supplied to an intercooler 53.
It is further guided to the heat exchanger 41 via a pipe line, and then supplied to the exhaust heat recovery boiler 73 via a pipe line 117.

The generator 118 is rotationally driven by the gas turbine device 60 and the steam turbine device 80, and the low pressure and high pressure compressors 52, 54 are also rotationally driven via the speed increasing gear device 119.

Next, a control system that enables the operation of this energy recovery device will be explained. Originally, in a fluid catalytic cracking apparatus, in order to keep the differential pressure between the tops of the reaction tower 3 and the regeneration tower 6 constant, as shown in FIG. The differential pressure Pd at the top of each tower is detected, and the differential pressure control device 130 compares it with the set value Pds output from the differential pressure setting device 124, performs a predetermined calculation, and uses the output to drive the slide valve 13. to control the differential pressure. the result,
The tower top differential pressure Pd is controlled to be Pd=Pds.

Next, in this energy recovery device, as shown in FIG. 124
Input a slightly smaller differential pressure setting signal Pd1 = (Pds - ΔPds) obtained by subtracting the minute deviation signal ΔPds set by the deviation setting device 126 from the differential pressure setting signal Pds from
A predetermined calculation is performed, and the output drives the control valve 33 of the expansion turbine device 31 to control the differential pressure. As a result, the tower top differential pressure Pd is controlled to Pd=Pd1.

In this way, expansion turbine pressure controller 122
Since the differential pressure set value Pd1 = (Pds - ΔPds) is set smaller by ΔPds than the differential pressure set value Pds of the differential pressure control device 130, the slide valve 13 is in a fully closed state under normal operating conditions. It is in a standby state so that it can be opened if the differential pressure at the top of the column becomes abnormally large due to some abnormality.

The bypass valve 36 provided in the expansion turbine equipment 31 is configured to temporarily prevent the top differential pressure Pd from being temporarily abnormal when the load of the generator 37 driven by the expansion turbine 34 is cut off and when the expansion turbine 34 is tripped. It is installed to act as a kind of safety device, such as forcing the valve to open using a feed forward control signal to prevent the valve from becoming too large.

When starting up the combined cycle equipment 32, the steam generated from the boiler 73 is passed through the pipe by steam supplied from the pipe 112 or by auxiliary combustion in the auxiliary combustion furnace 76. 113 to the steam turbine device 80 to drive the shaft system. When this rotational speed increases to a predetermined value, liquid fuel is supplied from the liquid fuel control valve 63 to the gas turbine device 60 to perform combustion in the combustor 62, and the gas turbine device 60 is started. As a result, when the pressure of the generated gas supplied from the fuel compressor device 50 via the pipe line 110 rises sufficiently, the generated gas is supplied via the gas fuel control valve 61 to convert the liquid fuel into Switching to using the generated gas, the gas turbine device 60 enters steady operation.

The exhaust heat recovery boiler device 70 warms up the flow rate of exhaust gas from the gas turbine device 60 via the pipe line 68 by operating two dampers 71 and 72 or by operating an auxiliary combustion furnace 76. At the time when this warm-up is completed, the pipe line 112, the flow control valve 1
11 and the pipe line 74 in this order, the steam supplied is cut off, and the steam from the boiler 73 is supplied to the steam turbine device 80.

The opening degree of the gas fuel control valve 61 provided in the gas turbine device 60 is controlled by the governor 132. The governor 132 responds to the rotational speed of the shaft system, and when driving the generator 118, the rotational speed control function of the governor 132 increases the rotational speed to the synchronous rotational speed of the generator system.
8 are connected to the power system in parallel to enable parallel operation. After this synchronization, the function of the governor 132 is switched from the rotational speed control function to the pressure control function.
The gas fuel control valve 6 is set so that the gas pressure P _F detected by the pressure detector 133 in the conduit 39 becomes the gas pressure set value P _FS set inside the governor 132.
Pressure regulating operation is carried out while controlling 1. If the operation of the gas turbine device 60 is restricted by some external condition, the pressure regulating operation is canceled and the gas turbine device 60 is operated within the range of the restriction conditions.

Flow rate control valve 7 in exhaust heat recovery boiler device 70
5 is controlled by a controller 140.
The controller 140 is given the output from the pressure detector 133 and also given a signal of the pressure P _F1 set by the pressure setting device 141. This pressure set value P _F1 is set to _a value _higher than the gas pressure set value P _FS set inside the governor 132 by _a minute differential pressure ΔP _FS . There is.

In this way, the flow rate of generated gas to the auxiliary combustion furnace 76 is controlled by the function of the controller 140, which is set at a slightly higher pressure P _F1 than the pressure P _F in the pipe line 39. The pressure of the generated gas in line 39 is adjusted to the value P _F1 .

The output from pressure detector 133 is also provided to controller 150. This adjustable type 150 includes:
A signal of pressure P _F2 from pressure setting device 151 is given. This pressure set value P _F2 is set to _{a value} higher than the pressure set value P _F1 input to _the controller 140 by _{the minute differential pressure ΔP SS .} ing. The output from the adjustment type 150 controls the opening degree of the safety valve 152. safety valve 15
2 is a 2-port slide valve 15 and a cooling pot 17
be interposed between. As described above, the gas pressure in the pipe line 39 is controlled by the governor 132 and the two controllers 141 and 15.
0, the gas fuel control valve 61, the flow control valve 75, and the safety valve 152 control each of them, but since each pressure setting value has a differential pressure, normally the gas fuel control valve 61 of the gas turbine device 60 is controlled first. is fully opened and P _F >P _FS , next, the flow control valve 75 of the waste heat boiler device 70 starts controlling. Further, even when the flow rate control valve 75 is close to fully open, the pressure still rises, and when the pressure of the generated gas in the pipe line 39 rises, when P _F >P _F2 ,
The safety valve 152 starts the control and the generated gas is released from the cooling pot 17 through the pipe 20 and out the chimney 19.

Next, regarding the control system of the steam system, the pressure of steam generated from the exhaust heat recovery boiler device 70 via the pipe line 74 is detected by the pressure detector 160, and its output is given to the controller 161. . The adjustment system 161 is connected to the pipe line 113 of the steam turbine device 80.
The opening degree of the regulating valve 81 interposed in the pressure control valve 81 is controlled so that the pressure in the pipe line 74 is kept constant.
When the steam pressure in the pipe line 74 further increases, the controller 170, which is given a steam pressure set value slightly higher than the steam pressure set value of the controller 161, operates to control the opening degree of the flow rate control valve 111. . Steam is thus supplied to the steam consumer via the flow control valve 111 and the line 112.

FIG. 2 shows an expansion turbine device 31 and a combined cycle equipment 32 of the embodiment shown in FIG.
This shows the operating status when both are stopped. In this operating state, gas generated from the cyclone dust collector 11 is guided from the slide valve 13 to the 2-port slide valve 15 via the multiple orifice 14.
It is radiated from the cooling pot 17 through the pipe 20 and from the chimney 19. In this way, safe fluid catalytic cracking operation continues. In FIG. 2, only the portion during operation is shown.

FIG. 3 shows a state in which the expansion turbine equipment 31 is stopped in the embodiment shown in FIG. During this operation, the cyclone dust collector 1
The generated gas from the slide valve 13 is led to the slide valve 15 via the multiple orifice 14, and is further supplied to the combined cycle equipment 32 through the pipe line 39 and the heat exchanger 41.

FIG. 4 shows the operating state when the combined cycle equipment 32 in the embodiment shown in FIG. 1 is stopped. The generated gas from the cyclone dust collector 11 passes through a pipe 30 to an expansion turbine equipment 31.
It is further supplied to the auxiliary combustion furnace 76 of the exhaust heat recovery boiler device 70 via the pipes 38 and 39. The exhaust gas from the auxiliary combustion furnace 76 is given to the boiler 73, and the exhaust gas is led to the chimney 76 through a pipe 75.

In this case, the water supplied from the pump 180 is guided from the condenser 83 to the intercooler 53 and further to the heat exchanger 41, where it is preheated and
17 and is supplied to the boiler 73.

According to such an embodiment, the entire amount of generated gas from the regeneration tower 6 is sent to the expansion turbine device 31, and the flow rate adjusting means such as the speed regulating valve 33 of the expansion turban 34 or the variable stator vane is driven to control the expansion turbine equipment. 31
The operating status of the gas turbine is controlled by the control device 122, and the generated gas whose pressure and temperature have been lowered in the expansion turbine equipment 31 is further cooled by the heat exchanger 41, and then the pressure is increased by the fuel compressor 50, and the gas is supplied to the gas turbine equipment 60 as fuel. supply High temperature exhaust gas generated in the gas turbine device 60 is supplied to the exhaust heat recovery boiler device 70, where steam is generated. The steam is supplied to a steam turbine unit 80 which works with a gas turbine unit 60 to generate a generator 118 which is a load.
The energy can be recovered as electric power or as motive power. Moreover, the water supplied to the exhaust heat recovery boiler device 70 is supplied to the steam turbine device 8
Water supply pump 115 from condenser 83 at 0
The intercooler 53 of the fuel compressor device 50
The high-temperature feed water that is further heated through the heat exchanger 41 and heated in this manner is sent to the boiler 73. In this way, energy recovery for the entire device can be performed with high efficiency. In this way, according to the embodiment of the present invention, the energy contained in the generated gas from the regeneration tower 6 can be effectively recovered in the expansion turbine device 31 and the combined cycle equipment 32. The great advantage is then achieved that energy recovery can be carried out without significant changes to the equipment for fluid catalytic cracking and without any adverse effects on the operation of the equipment. Furthermore, as described in relation to FIGS. 2 to 4, even if at least one of the expansion turbine equipment 31 or the combined cycle equipment 32 becomes abnormal and is disconnected and stopped, the operation of the other one continues. In this case, there will be no adverse effect on the operation of fluid catalytic cracking.

In the embodiment described above, the low pressure and high pressure compressors 5
2,54, air compressor 66 and gas turbine 6
Although the steam turbine 7 and the steam turbine 82 are connected to a single shaft system, they may not be connected to each other; for example, the low pressure and high pressure compressors 52, 54 are rotationally driven by a motor or the like. You can do it like this. Further, the blower 7 may be driven by a motor or the like. The expansion turbine equipment 31 may be omitted. The present invention
It can also be implemented to recover the energy of combustible gases generated from other chemical plants.

Effects As described above, according to the present invention, the gas generated from the regeneration tower is compressed and combusted in the fuel compressor, the exhaust gas is used to drive the gas turbine, and the exhaust gas is then heat-recovered in the boiler. . Steam from the boiler is supplied to a steam turbine. In this way, highly efficient heat recovery can be performed. Furthermore, the capacity of the fuel compressor system was reduced by expanding the generated gas from the regeneration tower using the expansion turbine equipment, lowering the pressure, lowering the temperature, and further lowering the temperature in a heat exchanger. Energy can be recovered from gas with even higher efficiency. That is, in the present invention, the gas generated from the regeneration tower is pressurized by a fuel compressor, and then combusted by a combustor of a gas turbine device to recover energy by driving a generator, for example, and
By guiding the high-temperature exhaust gas to the exhaust heat recovery boiler and recovering it as energy, it becomes possible to recover the energy of the generated gas more efficiently than by directly burning the generated gas in the boiler.

[Brief explanation of drawings]

FIG. 1 is a system diagram of an embodiment of the present invention, and FIG. 2 is an expansion turbine device 31 in the embodiment shown in the first diagram.
FIG. 3 is a system diagram showing the operating state when both the combined cycle equipment 32 and the combined cycle equipment 32 are stopped, and FIG. 3 shows the operating state when the expansion turbine equipment 31 in the embodiment defined in FIG. 1 is stopped. FIG. 4 is a system diagram showing the operating state when the combined cycle equipment 32 in the embodiment shown in FIG. 1 is stopped, and FIG. 5 is a system diagram of the prior art. 3... Reaction tower, 6... Regeneration tower, 11... Cyclone dust collector, 14... Multiple orifices, 15...
Slide valve, 17... Cooling pot, 31... Expansion turbine equipment, 32... Combine cycle equipment, 34... Expansion turbine, 42... Gas holder, 50... Fuel compressor device, 52... Low pressure compressor, 53 ... Intercooler, 54 ... High pressure compressor, 60 ... Gas turbine device, 62 ... Combustor, 66 ... Air compressor, 67 ... Gas turbine, 70 ... Exhaust heat recovery boiler device, 73 ... Boiler , 76... auxiliary combustion furnace, 80... steam turbine device, 82... steam turbine, 83... condenser, 119... speed increasing gear device.

Claims (1)

[Claims] 1. Crude oil is subjected to fluid catalytic cracking using a catalyst, and generated gas from a regeneration tower for regenerating the catalyst is led to a combined cycle facility, and in this combined cycle facility, the generated gas is subjected to fuel compression. The combustion gas from the combustor drives a gas turbine, the exhaust gas from the gas turbine is supplied to an exhaust heat recovery boiler to generate steam, and this steam is used to generate steam. An energy recovery device for gas generated from a fluid catalytic cracker regeneration tower, which drives a turbine. 2. A fuel compressor is driven by the power of at least one of the gas turbine and the steam turbine. Energy recovery device. 3. Crude oil is subjected to fluidized catalytic cracking using a catalyst, and the gas generated from the regeneration tower for regenerating the catalyst is lowered in pressure and temperature by an expansion turbine, and then guided to a combined cycle facility. The generated gas is pressurized by a fuel compressor and combusted in a combustor, the combustion gas from the combustor drives a gas turbine, and the exhaust gas from the gas turbine is supplied to an exhaust heat recovery boiler to generate steam. An energy recovery device for gas generated from a regeneration tower of a fluid catalytic cracker, characterized in that a steam turbine is driven by the steam.