JPS6185541A - Gas turbine generating plant using dirty gas containing hydrogen sulfide as fuel - Google Patents

Abstract

PURPOSE:To effectively use dirty gas by desulfiding and drying the dirty gas in advance together with burning it under pressure by compression. CONSTITUTION:Dirty gas containing hydrogen sulfide is supplied from a pipe passage 15 to a gas heat exchanger 16b first, then it is desulfided by means of a wet desulfiding equipment 18. It is supplied again to the gas heat exchanger 16b and pressurized through compression by a compressor 20, and then it is supplied to a combustor 22. With this contrivance, low-temperature corrosion can be prevented, while the dirty gas can be used effectively as gas turbine fuel.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a gas turbine power generation plant that uses dirty gas containing hydrogen sulfide as fuel, such as that emitted from a carbon black manufacturing process. [Prior Art] In general, the gas emitted from the carbon black manufacturing process, so-called tail gas, contains a considerable amount of hydrogen sulfide and usually 4
It is an extremely dirty gas with a water content of 0 to 50 g and a low calorific value.In order to reuse this dirty tail gas containing hydrogen sulfide, at most a water pipe boiler 2- There was no other way to use it as fuel. In other words, Figure 3 shows a conventional water tube boiler configuration that uses this kind of dirty gas containing hydrogen sulfide as fuel. 0 In this figure 3,
A water tube boiler 1 having an economizer 2 is supplied with tail gas as a fuel through a conduit 3 together with combustion air from a conduit 4 to be combusted, and is then supplied through a conduit 5 through the entirety of the economizer 2. The water thus obtained is heated and the steam thus obtained is supplied to, for example, a steam turbine power generation plant through a pipe 6 for use, and the exhaust gas discharged from a pipe T through an economizer 2 Due to environmental regulations, it is first desulfurized by a wet desulfurization device 8, and then reheated by a 77 taverner 9 to vaporize moisture, and then discharged into the atmosphere through a chimney 10. Sochiru.

Therefore, in the past, when dirty tail gas was used as fuel for a water tube boiler and the generated steam was used to operate a steam turbine power plant,
Desulfurization equipment 8 is required for flue gas treatment, which not only increases equipment costs but also requires poor plant assistance, and since it contains hydrogen sulfide, the outlet temperature of economizer 2 cannot be lowered much due to low-temperature corrosion problems. Therefore, naturally, the gay 2 efficiency will also decrease.Moreover, the exhaust gas that has passed through the desulfurizer 8 has high humidity and produces white smoke, especially in the winter, so the afterburner 9 is Disadvantages include the need to reheat to a level that does not produce white smoke.

[Summary of the invention]

In view of these conventional drawbacks, this invention uses dirty tail gas containing hydrogen sulfide and a low calorific value as fuel, desulfurizes and dries this gas in advance, compresses it under pressure, and combusts it. The present invention provides a gas turbine power generation plant in which a gas turbine is rotationally driven using a gas turbine.

〔Example〕

Hereinafter, one embodiment of the gas turbine power generation plant according to the present invention will be explained in detail with reference to FIGS. FIG. 1 is a block configuration diagram of a gas turbine power generation plant.

That is, in FIG. 1, the reference numeral 11 indicates a gas turbine power generation device, which has a known configuration consisting of a compressor 12, a gas turbine 13, and a generator 14, which are arranged coaxially and interlocked. It is.

Further, the tail gas used as fuel is once supplied to the gas heat exchanger 16 from the pipe 15, and then desulfurized through the wet desulfurization device 18 in the pipe 17, and then supplied to the gas heat exchanger 16 again. Then, it is introduced into a compressor 20 through a conduit 19 and compressed under pressure. At this stage, the tail gas initially supplied to the gas heat exchanger 16 has the desired sensible heat in itself, and is desulfurized by the wet desulfurization device 18 to remove a large amount of moisture. The tail gas after desulfurization, which has become a wet gas containing
Since it is not preferable to introduce the gas into the next stage compressor 20 in order to protect the compressor 20, the gas heat exchanger 16 is used to exchange heat with the tail gas before desulfurization. The subsequent tail gas is dried to the extent that it can be introduced into the compressor 20 to form a dry gas.Then, at this stage, the tail gas is desulfurized.

Regarding the dry S and subsequent pressurization and compressing processes, the desulfurization treatment of the tail gas in the wet desulfurization device 18 is such that the tail gas itself has been lowered in temperature by heat exchange in the gas heat exchanger 16, and is then sent to the wet desulfurization device 18. The gas inlet temperature of the wet desulfurizer 18 is sufficiently lower than that of the conventional example shown in FIG. In addition, the thermal energy required to turn wet gas into dry gas is extremely small, and all that is needed is to utilize the sensible heat possessed by the gas itself. Compared to the conventional example, there is an advantage that there is no need to waste heat energy just to prevent white smoke emission, and that the temperature is not affected by changes in atmospheric temperature.

As described above, the tail gas after desulfurization and drying that has been pressurized and compressed by the compressor 20 is supplied to the combustor 22 from the pipe 21, and is also compressed and compressed separately through the compressor 12. The combustion air is supplied from the pipe 23 and combusted, and the combustion gas causes the gas turbine 1
3 to rotationally drive the same congressor 12,
In addition, the power generation function of the generator 14 is obtained. Subsequently, the combustion exhaust gas that operated the gas turbine 13 is transferred to the pipe 2.
The exhaust heat of the combustion exhaust gas is introduced into the exhaust heat recovery boiler 25 from the combustion exhaust gas 4, and after being sufficiently recovered, it is discharged into the atmosphere from the chimney 2T through the pipe 26.

Again, in the exhaust heat recovery boiler 25, the exhaust gas after combustion has already been desulfurized before combustion, so the exhaust heat recovery in the exhaust heat recovery boiler 25 is not possible due to low-temperature corrosion caused by sulfuric acid. As mentioned earlier, reheating of the combustion exhaust gas to prevent white smoke emission as in the conventional example shown in Fig. 3 is almost impossible. In this way, an extremely high overall plant efficiency can be obtained. Incidentally, the exhaust heat recovery efficiency in the exhaust heat recovery boiler 25 is shown in FIG. This Fig. 2 is a heat recovery characteristic diagram with the vertical axis as temperature T and the horizontal axis as exchange heat iQ, where the symbol TP is the exhaust heat recovery boiler gas inlet temperature, T fz ,
Similarly, T rz is the outlet temperature, W is the flow rate of steam generated by the exhaust heat recovery boiler, and δT and ΔT' are the pinch points, and the smaller the minimum temperature difference between the heating side and the heated side, the larger the boiler heat transfer surface. is the minimum economical temperature difference.

δT can be designed at the sonominimum point, ΔT
The recovery efficiency is improved compared to '. In this way, the outlet gas temperature T' of the exhaust heat recovery boiler in cases where low-temperature corrosion is common as in the conventional example described above! When comparing these two, Tf'1) TP! From this relationship, it can be seen how effective the exhaust heat recovery efficiency is in this example.

[Effects of the Invention] As detailed above, according to the present invention, dirty tail gas with a low calorific value containing hydrogen sulfide, which is discharged from the carbon black manufacturing process, is used as fuel, and this gas is desulfurized in advance. By drying the gas, compressing it under pressure, and combusting it, this combustion gas is used to drive a gas turbine. Due to its simple device configuration, it can be effectively used as the ninth fuel in gas turbine power generation plants, and it also has features such as being able to completely recover exhaust heat from combustion exhaust gas to the maximum extent possible.

[Brief explanation of the drawing]

FIG. 1 is a block configuration diagram showing an overview of an embodiment of a gas turbine power generation plant according to the present invention, FIG. 2 is a characteristic diagram illustrating the exhaust heat recovery efficiency of the same exhaust heat recovery boiler, and FIG. FIG. 3 is a block diagram schematically showing a conventional water tube boiler that uses dirty gas containing hydrogen sulfide as fuel. 11.Gas turbine generator, 12.φ・Compressor? , 13...-gas turbine, 14...-generator, 16-fist/fist gas heat exchanger, 18--wet desulfurization equipment, 20---compressor, 22...- combustor , 25...Exhaust heat recovery boiler. Patent mountain applicant Mitsui Engineering & Shipbuilding Co., Ltd.

Claims (1)

[Claims] It has a gas turbine power generation device in which a compressor, a gas turbine, and a generator are arranged so that they can be linked together on the same axis, a heat exchanger, and a wet desulfurization device, and the tail gas containing hydrogen sulfide is transferred from the heat exchanger to the wet desulfurization device. Desulfurization and drying means for tail gas which is desulfurized through a desulfurization device and then converted into dry gas by a heat exchanger; a compressor for pressurizing and compressing the desulfurized and dried gas; and a compressor for compressing the desulfurized and dried gas; a combustor that combusts the gas turbine along with pressurized combustion air from the compressor of the gas turbine power generator; a means for rotationally driving the gas turbine with the combustion gas; and an exhaust heat recovery system that recovers exhaust heat from the exhaust gas that has passed through the gas turbine. A gas turbine power generation plant that uses dirty gas containing hydrogen sulfide as fuel, and is characterized by being equipped with a boiler.