JPS5947141B2 - Vanadium high temperature corrosion inhibitor additive amount control device - Google Patents

Description

Detailed Description of the Invention The present invention provides an inhibitor for suppressing high-temperature corrosion caused by vanadium (hereinafter abbreviated as V) contained in the fuel in fuel consumption equipment that uses inferior fuel such as heavy oil or crude oil. This invention relates to an addition amount control system when adding to the inside.

In gas turbine equipment that uses inferior fuel such as heavy oil or crude oil, pretreatment of the fuel is generally required in many cases.

The reason is that these inferior fuels contain sodium (N
During combustion, metal elements such as potassium (abbreviated as a), potassium (abbreviated below), and V combine with oxygen and sulfur to produce compounds with low melting points, which weld to the metals in the high-temperature gas passage section of the gas turbine and This is because it corrodes. Regarding Na contained in poor quality fuel, remove it by washing with water before supplying the fuel to the gas turbine combustor, or blend it with high quality fuel that does not contain Na, to reduce the total Treatment is performed to reduce the content of Na to a value where the effect of corrosion can be virtually ignored.

On the other hand, for V, magnesium-based inhibitors (e.g. MgSO4/R
It is necessary to add lH2O (dissolved in silicone oil) to generate a compound consisting of V and Mg and to prevent the formation of the low melting point compound.

Among the above processing methods, a system that blends high-quality oil with fuel containing Na and K is already known, and if the blend ratio and fuel oil pressure after blend control are given as set values, fluctuations in fuel flow rate can be controlled. The present inventors have developed and are operating a system that can completely and automatically track the above.

On the other hand, regarding the control system of V's high-temperature corrosion inhibitor,
Since it was thought that the precision of blending control was not necessary, it was still connected to a simple hand-operated system.

A fuel supply system including the above blend system and V inhibitor addition amount control system will be explained in more detail with reference to FIG.

In Figure 1, 1A is a transfer system for good quality fuel A, 1B is a transfer system for poor fuel B containing Na, K, etc., and 2 is a system for combining fuels A and B and transferring them to the combustor 29 of the gas turbine. A blend transfer system is shown. Each fuel transfer system 1A, 1
B has fuel tanks 3A, 3B1 and transfer pump 4, respectively.
A, 4B, flow rate detector 5A, 5B1 flow rate control valve 6A, 6
B is installed. The blend transfer system 2 includes a flow meter 12, a main fuel pump 25, and a flow rate controller 26 installed in parallel with the pump and opened and closed by a flow rate control signal 27.
is installed. 18 is a V inhibitor added line,
This is installed connected to the blend transfer system 2, and includes a V inhibitor tank 19, a transfer pump 20 and a flow rate controller 22 installed in parallel, a flow meter 24, and a check valve 23.
It consists of

Control of the blend ratio in such a fuel transfer system is
This is done as follows.

The flow rates FMA and FMB of each fuel A and B are determined by the flow rate detector 5A,
5B, and using these flow rate signals, the blend ratio R1 is determined by the calculator 7, and this blend ratio R
1 and the set blend ratio R from the blend ratio setting device 9. are compared by a comparator 8, and the deviation is integrated by an integrator 10,
A part of the integrated output is branched by the computing unit 11 as a deviation signal for fuel A. On the other hand, the pressure after blending is detected by the pressure detector 13, the detected pressure signal P1 is compared with the setting signal PO from the pressure setting device 15 by the comparator 14, the deviation is integrated by the integrator 16, and the output is The integrator 1
0 and the output of the arithmetic unit 11 are multiplied by multipliers 17B and 17A, and the output signal of the multipliers 17A and 17B is used to control the flow rate control valve 6.
Control A and 6B. In this way, by controlling the flow rate control valves 6A and 6B in consideration of the pressure after blending, the flow control valves 6A and 6B can be controlled regardless of pressure fluctuations after blending, that is, regardless of fluctuations in the fuel flow rate required by the gas turbine fuel control system. It becomes possible to keep the blend ratio and the fuel oil pressure after blending constant. On the other hand, the V
The addition amount in the inhibitor addition system 18 is controlled by detecting the vanadium concentration in the fuel stored in the fuel tank 3B in advance with the concentration detector 28, and determining V based on this concentration, the flow rate detected by the flow meter 12, and the blend ratio. Inhibitor flow rate setting signal F.

The driver calculates the amount, applies it to the flow controller 22 by operating the V inhibitor flow rate setting device 21, and checks with the flow meter 24 whether the flow rate is flowing according to the set value. . The amount of inhibitor added is 60001/Hr for fuel containing 2 to 5 ppm(7)V.
When it is flowing, it is about 21/Hr. Such a V inhibitor addition amount control system controls the V inhibitor addition amount to the V in the fuel when the fuel flow rate and blend ratio are kept unchanged.
This is effective because the amount can be set to match the amount of V suppressor, but if the flow rate and blend ratio change, it is necessary to calculate the necessary amount of V suppressor added each time and reset the amount. If the fuel flow rate or blend ratio changes over a short period of time, it is impossible to accurately set the amount of inhibitor added.

Furthermore, calculation of the V inhibitor addition amount itself requires some skill, as it is necessary to know the blend ratio, the fuel flow rate measured by the flow meter 12, and the V concentration in fuel B. There's a problem. In addition, currently, even if the addition ratio of the V inhibitor slightly exceeds the specified value, the effect is limited to an increase in the ash content in the combustion gas, so the maximum fuel flow rate must be assumed in advance and the flow rate setting device 21 The method used is to adjust the amount of V inhibitor added two or three times to fix the setting to the amount of V inhibitor added that corresponds to that value, but if the content in the fuel is less than the set amount, expensive inhibitors may be added. On the other hand, when the amount of V in the fuel increases, the amount of ash generated by untreated V increases, and this ash becomes a problem as a source of pollution. Since the gas adheres to the high-temperature gas section (for example, accumulates in the nozzle section and reduces the cross-sectional area of the flow path), this causes a problem in that maintenance intervals for these sections are shortened.

The purpose of the present invention is to eliminate the drawbacks of the conventional V inhibitor addition system, and to provide a V suppressor that can maintain the optimum amount of V inhibitor even if the fuel flow rate, V concentration in the fuel, etc. fluctuate. The purpose of the present invention is to provide a system for controlling the amount of additive added.

In order to achieve this objective, the V inhibitor addition amount control system according to the present invention uses the V inhibitor addition amount control system based on the flow rate signal of inferior fuel and the V concentration signal
The present invention is characterized in that it includes a calculation device that determines the required addition amount of the inhibitor, and a flow rate control device that controls the addition amount of the V inhibitor based on the output of the calculation device.

Next, an embodiment of the V-inhibitor addition amount control system according to the present invention will be described with reference to FIG. 2, taking a gas turbine fuel supply system as an example.

In FIG. 2, the blending system for poor fuel and good fuel is the same as in FIG. 1, and the same parts in other systems are given the same reference numerals. Reference numeral 30 indicates a signal path for transmitting a flow rate signal FMB detected by the flow rate detector 5B of inferior fuel containing V; 31 indicates a unit V concentration in fuel B (for example, 1 ppm);
) is a constant device that gives a conversion rate between the fuel flow rate and the amount of V suppressant added per unit (for example, M
FM depending on the size of n in gSO4/NH2O
The flow rate signal of B is multiplied by an arbitrary coefficient k.

33 is the V concentration C detected in advance by the V concentration detector 28;

This is a V concentration setting device. 32 is this V concentration signal C.

and the V-inhibitor addition amount signal F1 which is the output of the constant unit 31, and the output signal Q of this multiplier 32 is the required addition amount signal of the V-inhibitor. That is, the required addition amount signal Q is expressed by the following formula.゛ι ▲ 1i1Vυ star ι
' “ ↓ ▲▼Todoroki D- ゜Vυ34 is the required addition amount signal Q and the flow rate detector 3 installed in the V inhibitor addition line.
This is a comparator that compares the flow rate signal FMD of No.6.

35 is a flow rate controller installed in parallel with the V inhibitor transfer pump 20, and is controlled by the output signal of the comparator 34 so that the difference between the output of the comparator, that is, the signal Q and FMD becomes zero. It is something.

In this example, the flow rate and V concentration of inferior fuel containing V are detected to determine the necessary amount of V inhibitor added.
Since the necessary addition amount is secured regardless of the blend ratio or fuel flow rate, there is no need to consider the blend ratio, and once the V concentration signal is given, the fuel flow rate can be adjusted due to fluctuations in the turbine load, etc. Even if it fluctuates, the amount of V inhibitor added can be continuously controlled.

In addition, since a constant unit 31 is provided before the multiplier 32 and the coefficient is changed depending on the type of inhibitor to be added,
It is possible to obtain the amount of v-inhibitor added that suits the actual situation. Furthermore, in order to realize the system of this embodiment, the flow rate signal of the flow rate detector 5B is branched, and the constant device 31. Multiplier 32
, a relatively simple modification of adding a comparator 34 is required, and furthermore, the detector 12 for detecting the fuel flow rate after blending is not required, so it is very attractive from an economical point of view. The embodiment shown in FIG. 2 describes an example in which the present invention is applied to a blending system that has a large economic effect. , or Na,K
It can also be adopted in a fuel supply system consisting only of fuel containing only a small amount of An example in this case is shown in FIG. In this case, it is necessary to install a flow rate detector 5B exclusively for controlling the amount of V inhibitor added, but the control method is the same as the embodiment shown in Fig. 2, and the optimum amount of V inhibitor added is ensured. The same effect can be achieved in that The present invention is not limited to the above-mentioned embodiments, and various modifications are possible.
For example, it is also possible to obtain the relationship between the operation amount of the flow rate controller 35 and the V inhibitor flow rate in advance, and operate the flow rate controller 35 using the output of the multiplier 32 itself. Further, if the composition of the V suppressor is constant, the constant device 31 is not necessarily necessary. Further, the present invention can be applied to fuel consumption devices other than gas turbine combustors. As described above, the V inhibitor addition amount control system according to the present invention includes a calculation device that calculates the necessary addition amount of the V inhibitor from the flow rate of inferior fuel containing V and the V concentration, and a calculation device that calculates the necessary addition amount of the V inhibitor based on the output of the calculation device. This system consists of a flow rate controller that controls the amount of V inhibitor added to the fuel, and the optimum amount of V inhibitor added is ensured regardless of fluctuations in fuel flow rate. There is no need to waste due to too much or ash due to too little, making it possible to prevent pollution problems and extend maintenance work intervals.

The present invention exhibits greater effects as the V concentration in the fuel increases.

[Brief explanation of the drawing]

Fig. 1 is a system diagram showing a V-inhibitor addition system including a conventional blend system, Fig. 2 is a system diagram showing an embodiment of the V-inhibitor addition system according to the present invention, and Fig. 3 is a system diagram showing an embodiment of the V-inhibitor addition system according to the present invention. It is a system diagram showing an example. 3A...Good quality fuel tank, 3B...Poor fuel tank, 4A, 4B...Fuel pump, 5
A, 5B, 36...Flow rate detector, 6A, 6B・
...Flow rate control valve, 19...V inhibitor tank, 20...V inhibitor transfer pump, 25...
... Main fuel pump, 26, 35 ... Flow rate controller, 29 ... Combustor, 31 ... Constant device, 32 ... Multiplier, 33...Concentration setting device, 34...Comparator.

Claims (1)

[Scope of Claims] 1. A fuel transfer system that transfers fuel to the combustion chamber of a gas turbine, a flow rate detector that detects the flow rate of fuel flowing through the transfer system, and an inhibitor addition that adds a vanadium inhibitor to the transfer system. system, a calculation means for calculating a necessary addition amount of vanadium high temperature corrosion inhibitor from a fuel flow rate detection value signal from the detector and a pre-detected vanadium concentration value supplied through the transfer system, and the calculation device. a flow rate control means for controlling the amount of vanadium high-temperature inhibitor added by the inhibitor addition system based on the output signal of the vanadium high-temperature corrosion inhibitor addition amount control device. 2. A fuel transfer system that transfers fuel to the combustion chamber of a gas turbine, a first supply system that is provided upstream of the transfer system and supplies good quality oil that does not contain vanadium to the transfer system, and a first supply system that supplies poor quality oil that contains vanadium. , a second supply system that supplies blended fuel with high-quality oil to the transfer system, a flow rate detector that detects the flow rate of fuel flowing through the second supply system, and an inhibitor that adds a vanadium inhibitor to the transfer system. an addition system; a calculation means for calculating the required addition amount of the vanadium high-temperature corrosion inhibitor from a fuel flow rate detection value signal from the detector and a pre-detected vanadium concentration value supplied through the transfer system; A vanadium high-temperature corrosion inhibitor addition amount control device comprising: a flow rate control means for controlling the addition amount of vanadium high-temperature inhibitor by the above-mentioned inhibitor addition system based on an output signal of the device. 3. The calculation means is characterized by comprising a constant device that gives an arbitrary conversion rate to the vanadium concentration value in the fuel, and a multiplier that multiplies the output signal of the constant device by the vanadium concentration signal in the fuel. A vanadium high-temperature corrosion inhibitor addition amount control device according to claim 2. 4. The control device according to claim 2, wherein the inhibitor addition system has its own negative feedback control system.