JP2011007193A - Intake air filter unit for gas turbine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intake air filter unit for a gas turbine, allowing reduction of an installation space for the filter unit without requiring cleaning of an air compressor or the like and filter replacement over a prolonged period of time.SOLUTION: In this intake air filter unit for the gas turbine formed by providing dustproof filters in two or more stages, the filter unit is composed of three stages, that is, a panel-type demister 2, a wind up belt type or windsock type pre-filter 3 and a high performance suction filter 4 for the gas turbine, from an upstream side in an air flow direction, the high performance suction filter for the gas turbine is composed by closely piling low efficiency filtering material and high efficiency filtering material from the upstream side in the air flow direction, filter material area of each filtering material is set in 20-35 m/unit, filtering material of 40-70% filtering efficiency in relation to 0.3 μm diameter particles is arranged in a layer on the upstream side in the air flow direction, filtering material of 90-99.99% filtering efficiency in relation to 0.3 μm diameter particles is arranged in a layer on a downstream side in the air flow direction, and a pressure drop when air volume 50 m/minute is maintained at 150-450 Pa.

Description

  The present invention reduces the generation output by reducing the adhesion of atmospheric dust to an air compressor or the like of a gas turbine plant, and eliminates the need for cleaning the air compressor or replacing a filter over a long period of time. More specifically, the present invention relates to a gas turbine intake filter unit that can reduce the installation space of the filter unit.

As shown in FIG. 8, the gas turbine a sucks outside air b during operation. Since atmospheric dust such as fine dust, rain water, mist, carbon fine particles in exhaust gas, and salt particles floats in the outside air b, such atmospheric dust causes corrosion and contamination inside the gas turbine. In particular, there is a problem in that it adheres to the air compressor c and causes a reduction in the performance of the air compressor c, thereby reducing the power generation output. Therefore, in order to prevent the inhalation of atmospheric dust, a dust collector (filter unit) e for mechanically separating and removing atmospheric dust from the air is provided at the air inlet d of the gas turbine a. is set up. As disclosed in Japanese Patent Application Laid-Open No. 5-106464, the filter unit e includes a coarse filter f made of a filter material of a wound belt glass fiber, and a medium performance filter g in which an ion exchange fiber filter is folded. It is configured in two stages.
In the drawing, h represents a turbine portion of the gas turbine a, and i represents a generator driven by the gas turbine a. Since the conventional gas turbine intake filter unit cannot sufficiently remove atmospheric dust, the power generation output of the gas turbine is reduced, and the dust holding capacity is small, so the filter needs to be replaced twice or three times a year. It becomes. For this reason, there is a demand for a long-life gas turbine intake air filter unit that can be replaced during a periodic inspection of a gas turbine that is required once a year with a highly efficient intake air filter unit that does not reduce power generation output.

In order to meet the above-mentioned demands, the present inventors have proposed a panel type demister or weather louver, a take-up band type or windsock type prefilter, a box type medium performance filter, and a box type high performance filter. However, there is a problem that the intake filter unit becomes large and the installation space and equipment cost increase, and countermeasures are desired. Thus, from the viewpoint of low pressure loss, high efficiency, and long life, it was concluded that a medium performance filter and a high performance filter should be combined, and the prior art related to the combination was referred to, but each had problems. First, for the purpose of reducing the installation space, Japanese Utility Model Publication No. 62-132715 discloses a filter paper having a predetermined ability on the downstream side of the gas flowing in the casing, and has a lower collection ability than the filter paper on the upstream side. Although it has been disclosed that filter paper is provided in multiple stages, there is a problem that the purpose of reducing the installation space cannot be achieved without reducing the filter.
In addition, for the purpose of removing salt particles, Japanese Utility Model Publication No. 3-35373 discloses that a gap holder having a void portion is sandwiched between two filter media having water repellency. This is because even if the particles become water droplets, the droplets are dropped along the back surface of the filter medium on the upstream side, the thickness of the filter medium is increased, and the filter medium area cannot be increased in order to have a lifetime of 8000 hours or more. In addition, there is a problem that the pressure loss increases.
Further, for the purpose of obtaining a high efficiency of filtration efficiency (0.1 μm DOP) of 99.99% or more (so-called ULPA), Japanese Patent Application Laid-Open No. 54-94176 discloses that a filter medium is composed of two layers, A filter medium having a filtration efficiency of 99.97% or more with respect to particles having a particle diameter of 0.3 μm is disposed in the downstream layer, and 99.97 with respect to particles having a particle diameter of 0.3 μm is disposed in the upstream layer. It is disclosed that a filter medium having a filtration efficiency of less than 75% and 75% or more is disposed, and these two layers of filter medium are folded in a zigzag shape in a closely overlapped state. The filter medium is assumed to have two layers from the viewpoint of dimensional constraints and ease of production, but the purpose is high efficiency, and the life is not considered, and when used for gas turbines, the filter medium is clogged quickly. It is necessary to carry out filter replacement 2-3 times a year There is a problem in that that.
Therefore, as disclosed in Japanese Patent Application Laid-Open No. 7-253029, in order to solve the above problems, the applicant closely overlaps the low-efficiency filter medium and the high-efficiency filter medium from the upstream side in the airflow direction. The filter medium has an area of 25 to 35 m ² / unit, and the filter medium has a filtration efficiency of 10 to 70% with respect to particles having a particle diameter of 0.3 μm in the upstream layer with respect to the airflow direction. A high performance filter for gas turbine intake was proposed in which a filter medium was disposed, and a filter medium having a filtration efficiency of 90 to 99.99% with respect to particles having a particle diameter of 0.3 μm was disposed in the downstream layer.
However, although the atmospheric dust used for the initial evaluation had an excellent effect of having a lifetime of 8000 hours or more, when it was re-evaluated with another atmospheric dust, the pressure loss of the filter unit increased rapidly in about 4300 hours. It was found to be a lifetime. The reason for this is that the concentration of fine dust typified by a particle size of 0.3 μm in the atmospheric dust was very high, about 5 times the original, and the load was concentrated on the downstream layer.

JP-A-5-106464 Japanese Utility Model Publication No. 62-132715 Japanese Utility Model Publication No. 3-35373 JP 54-94176 A Japanese Patent Laid-Open No. 7-253029

  For this reason, even atmospheric dust with a high concentration of fine dust represented by a particle size of 0.3 μm ensures a life of 8000 hours or more and prevents atmospheric dust against the air compressor of a conventional gas turbine plant. A gas turbine intake high-performance filter that prevents the reduction of power generation output by reducing adhesion, eliminates the need to clean the air compressor, filter replacement, etc. over a long period of time, and makes the filter unit installation space compact. It aims at providing the filter unit for gas turbine intake using this.

In order to solve the above problems, the gas turbine intake filter unit of the present invention is a gas turbine intake filter unit comprising a plurality of stages of dustproof filters. The dustproof filter is disposed on the panel from the upstream side in the airflow direction. The gas turbine intake high-performance filter consists of a low-efficiency filter medium and a high-efficiency filter medium from the upstream side in the airflow direction. The filter medium structure of each filter medium is 20 to 35 m ² / unit, and the layers upstream of the flow direction are 40 to 70% with respect to the particles having a particle diameter of 0.3 μm. pressure when in arranged filter media filtration efficiency, arranged filter media filtration efficiency of 90 to 99.99% with respect to particles having a particle diameter of 0.3μm is the layer of the downstream side, the air volume 50 m ³ / min It characterized in that the loss was 150～450Pa.
In addition, the filter medium is folded in a zigzag shape so as to be uneven with respect to the air flow direction, and a separator that refracts the sheet into a wave shape is inserted into the folding interval portion, and the refraction wave height of the separator is set to the rear end in the insertion direction. It is preferable that the height on the side is larger than the height on the distal end side in the insertion direction to be tapered, but it is not necessarily limited to the separator type, and may be a mini pleat type or a double pleat type.
In the gas turbine intake filter unit of the present invention, the pre-filter is a blow-off type and has a filter medium area of 2 to 8 m ² / unit.

As described above, by using the gas turbine intake filter unit invented this time, even when used in an environment where the concentration of fine dust typified by a particle size of 0.3 μm is high, once a year in accordance with laws and regulations. Maintenance work such as filter replacement and compressor cleaning can be reduced. For example, it is possible to replace the filter during regular inspection.
In addition, since a filter having high collection efficiency represented by a HEPA filter (so-called high performance filter) is used, the output reduction of the gas turbine due to adhesion of atmospheric dust can be suppressed, and the intake filter unit can be made compact and saved. Space can be achieved.

Configuration of the gas turbine intake filter unit of the present invention Partial cut front view of a winding band type prefilter Side view of the filter media of a streamer type prefilter Front view of the head of the filter medium Top view of the windsock prefilter High-performance filter perspective view Partial cut plan view of the high performance filter Configuration diagram of conventional gas turbine intake filter unit

  The panel-type demister constituting the gas turbine intake filter unit of the present invention is for preventing rainwater from entering, and there are various known ones. For example, animal and vegetable fibers and synthetic fibers are spring-shaped. It is known that a large number of small elastic bodies are made by curling, and these are coated and bonded with a binder into a plate shape and enclosed in a metal frame. In general, the demister has a thickness of 10 to 50 mm, a filtration efficiency (JIS 8 type, colorimetric method) at a wind speed of 2 m / s of 15 to 60%, and a pressure loss of 10 to 100 Pa. The demister is characterized by low pressure loss, that is, low ventilation resistance and high filtration efficiency against water droplets, and when it becomes dirty, it can be reused by removing it from the frame and washing. Of course, instead of the panel type demister, a refraction type weather louver or the like that prevents intrusion of rainwater by a refraction path can be used.

In addition, as the pre-filter constituting the gas turbine intake filter unit of the present invention, a winding band type or a blower type is used, and the winding band type is formed from a glass fiber filter medium as shown in FIG. The belt-shaped filter medium 10 is stretched so as to block the intake air passage 11, and the feed roll 12 around which the filter medium 10 is wound is installed on the upper side, while the filter medium 10 taken out from the feed roll 12 is provided. A take-up roll 13 is installed at the bottom. In general, the wound belt-shaped prefilter is a nonwoven fabric using glass fiber, polyester fiber, or the like as a filter medium material. The filter medium thickness is 20 to 70 mm, the average fiber diameter is 15 to 60 μm, and the wind speed is 2.5 m / s. The pressure loss is 40 to 80 Pa, the filtration efficiency (JIS 15 species, weight method) is 60 to 90%, and the dust holding capacity is 500 to 1300 g / m ² .
However, since the winding belt-shaped mold requires maintenance of the filter medium winding drive device, the following blow-off mold with a wide filter medium area is preferable for complete maintenance-free.
As shown in FIGS. 3 to 5, the streamer type has a shape in which a large number of bag bodies 21 are made continuous with a filter medium 20, and a head section 24 having a plurality of bars 23 with the filter medium 20 aligned with its opening 22. It attaches to the frame 25 with the screw 26 via.
In this prefilter, the filter medium has an average thickness of 5 to 25 mm, the material is a dry nonwoven fabric of organic fibers such as polyester and acrylic, the average fiber diameter is 5 to 60 μm, the basis weight is 50 to 600 g / m ² , and the wind speed is 2.5 m / s. The pressure loss is 20 to 300 Pa, the efficiency (JIS 15 types, weight method) is 60 to 99%, the filter medium area is 2 to 8 m ² / unit using this filter medium, and the external dimensions are vertical 592 mm × horizontal 592 mm × depth. A 500 mm windsock prefilter was obtained. However, the form is not limited to this, and any shape can be used as long as the filter medium area can be made desired.
When the filter medium area is less than 2 m ² / unit, the desired filter unit life cannot be obtained, and when the filter medium area exceeds 8 m ² / unit, the pressure loss increases, which is not preferable. Accordingly, the filter medium area is preferably ² to 8 m ² / unit.
The filter has a pressure loss of 20 to 80 Pa at an air volume of 50 m ³ / min, an efficiency (JIS 15 type, weight method) of 60 to 99%, and a dust holding capacity of 500 to 4000 g / unit.

The high performance filter for gas turbine intake used in the filter unit for gas turbine intake of the present invention is obtained by a combination of a high efficiency filter medium and a low efficiency filter medium. The high efficiency filter medium has a particle size of 0.3 μm. A filter having a filtration efficiency of 90 to 99.99% based on the particles is used.
If it is less than 90%, dust adhesion of the compressor of the gas turbine cannot be prevented, and if it exceeds 99.99%, it is effective for preventing dust adhesion, but pressure loss increases and life is shortened. It is because it produces.
Moreover, as a low efficiency filter medium, the thing of the filtration efficiency of 40 to 70% is used with respect to the particle | grains with a particle size of 0.3 micrometer. This is because the load of the high-efficiency filter medium on the downstream side becomes large in the case of atmospheric dust with a high concentration of fine dust represented by a particle size of 0.3 μm if it is less than 40%, and the mesh of the filter medium if it exceeds 70%. This is because there is a problem that clogging is accelerated.
These high-efficiency filter media 30a and low-efficiency filter media 30b are closely overlapped and folded in a zigzag shape so as to be uneven with respect to the flow direction of the intake air in order to increase the filter media area. A separator 33 is inserted into the frame 31 via a sealing material 32, and a sheet 33 is bent into a wavy interval portion.
As shown in the figure, by using a so-called inclined separator in which the wave height of the refraction of the separator 33 is formed in a tapered shape by making the height H1 on the rear end side in the insertion direction larger than the height on the front end side H2 in the insertion direction. The filter can have high airflow and high performance as compared with a normal separator in which the wave height of refraction is made uniform over the entire length.
This high-performance filter generally has a total thickness of each filter medium of 0.4 to 2.0 mm, a basis weight of 100 to 200 g / m ² , a pressure loss of 50 to 450 Pa at a wind speed of 5.3 cm / s, and an efficiency. (0.3 μm DOP) is 90 to 99.9%, and the separator is made of metal foil such as aluminum or stainless steel, paper such as craft or synthetic fiber, synthetic resin film such as polyarylate, polyethylene terephthalate, etc. When a folding separator is inserted and the outer dimensions are vertical 610 mm × width 610 mm × depth 290 mm, the filter medium area is 25 to 35 m ² / unit, and when the outer dimensions are vertical 594 mm × width 594 mm × depth 290 mm, the filter medium area is 20 to A high-performance filter of 30 m ² / unit was used. If the area of the filter medium is less than 20 m ² / unit, the pressure loss increases and the life is shortened. If the area exceeds 35 m ² / unit, there is a problem that the distance between the filter medium and the filter medium cannot be maintained. Therefore, the filter medium area is 20 to 35 m ² / unit.
The performance of this filter is such that the pressure loss at an air flow rate of 50 m ³ / min is 150 to 450 Pa, the efficiency (0.3 μm DOP) is 90 to 99.99%, and the dust holding capacity is 1000 to 3000 g / unit.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 shows an embodiment of a gas turbine intake filter unit according to the present invention, in which dust harmful to the continuous operation of the gas turbine is removed from the intake air in a casing 1 installed in the intake duct of the gas turbine. For this purpose, a three-stage filter unit 5 comprising a weather louver 2, a blow-off type prefilter 3, and a high performance filter 4 of the present invention is provided.

  The weather louver 2 is formed by bending a metal plate into a substantially U-shaped cross section so as to prevent the intrusion of rainwater. The pressure loss is about 20 Pa for a wind speed of about 2.5 m / s. One unit having a raindrop collection efficiency of 88% (weight method) and an outer diameter of about 2600 mm in length, 3300 mm in width, and about 200 mm in depth was installed in the casing 1.

The prefilter 3 is a nonwoven fabric filter material made of polyester fiber (average fiber diameter 19 μm, average weight 330 g / m ² , average thickness 18 mm) is folded into six piles, fixed with a metal frame, and the filter medium area is 4 m ² / unit. Using a filter having dimensions of 592 mm in length, 592 mm in width, and 500 mm in depth, 20 units (4 stages × 5 rows) were installed in the casing 1. The performance of this prefilter is such that the initial pressure loss is about 60 Pa and the collection efficiency (JIS 15 seed powder, weight method) is 98% with respect to the used air volume of about 50 m ³ / min.

The high-performance filter 4 collects a glass fiber paper filter with a collection efficiency of about 40% for particles with a particle size of 0.3 μm on the upstream side in the airflow direction, and for particles with a particle size of 0.3 μm on the downstream side. A glass fiber paper filter medium with an efficiency of about 97% is closely stacked, an aluminum foil separator is inserted and folded in a zigzag shape, the filter medium area is 25 m ² / unit, and the external dimensions are 610 mm long × 610 mm wide × 290 mm deep. A filter was used, and 20 units (4 stages × 5 rows) were installed in the casing 1. The performance of this high-performance filter is an initial pressure loss of about 250 Pa and a collection efficiency (counting method, target 0.3 μm particles) of 97% with respect to an operating air volume of about 50 m ³ / min.

The gas turbine intake filter unit 5 of the present embodiment, which is composed of the weather louver 2, the pre-filter 3 and the high-performance filter 4, has the same weather louver 2, pre-filter 3 and upstream filter medium with a particle size of 0. It consists of a glass fiber paper filter medium with a collection efficiency of about 15% for 3 μm particles and a high-performance filter closely packed with 97% glass fiber paper filter medium for particles with a particle diameter of 0.3 μm on the downstream side. As a comparative example, the filter unit for intake air having an average weight concentration of about 0.13 mg / m ³ and an average number concentration of particles having a particle size of 0.3 to 0.5 μm is 500,000 / 0.1 cf. Continue to continuously flow outside air with a high concentration of fine dust, and during that period the output of the gas turbine decreases and the filter life (until the pressure loss reaches 686 Pa) Were evaluated for such time). The configuration of each of the intake filter units is shown in Table 1 below, and the test results are shown in Table 2.

As can be seen from Table 2, the configuration of the comparative example gives good results in terms of prevention of gas turbine output reduction, space saving, and maintenance, but the fine dust typified by a particle size of 0.3 μm. When used in a high-concentration environment, the lifetime is shortened to 4300 hours, and the filter needs to be replaced about twice a year.
In contrast, the configuration of the embodiment of the present invention can prevent gas turbine output from decreasing and save space even when used in an environment where the concentration of fine dust represented by a particle size of 0.3 μm is high. In addition, maintenance-free for 8000 hours (equivalent to one year) or more can be achieved.

  Since it is possible to provide a filter unit for gas turbine intake that prevents a decrease in power generation output and does not require cleaning of an air compressor or the like and replacement of a filter for a long time, it has industrial applicability.

DESCRIPTION OF SYMBOLS 1 Casing 2 Weather louver 3 Winding band type or wind-flow type pre filter 4 High performance filter 5 Gas turbine intake filter unit 30a High efficiency filter medium 30b Low efficiency filter medium 31 Frame body 32 Seal material 33 Separator

Claims (3)

In a gas turbine intake filter unit having a plurality of dustproof filters, the dustproof filter is a panel type demister, a take-up band type or blown type prefilter, and a high performance filter for gas turbine intake from the upstream side in the air flow direction. The high-performance filter for gas turbine intake has a low-efficiency filter medium and a high-efficiency filter medium closely stacked from the upstream side in the airflow direction, and the filter medium area of each of these filter media is 20 to 35 m ² / unit. The filter medium is configured such that a filter medium having a filtration efficiency of 40 to 70% with respect to particles having a particle diameter of 0.3 μm is disposed in the upstream layer with respect to the air flow direction, and a particle diameter of 0.3 μm is disposed in the downstream layer. 90 to 99.99% filtration arranged filter media efficiency, the filter for a gas turbine inlet air, characterized in that the pressure loss when the air volume 50 m ³ / min was 150~450Pa against particles Knit.   The filter medium is folded in a zigzag shape so as to be uneven with respect to the airflow direction, and a separator that refracts the sheet into a corrugated shape is inserted into the folding interval, and the refraction wave height of the separator is set to a height on the rear end side in the insertion direction. 2. The gas turbine intake filter unit according to claim 1, wherein the filter unit has a taper shape with a height larger than a height at a distal end side in the insertion direction. ^2. The gas turbine intake filter unit according to claim 1, wherein the prefilter is a blow-off type and has a filter medium area of 2 to 8 m ² / unit.

Images