JP2007211785A - Suction filter unit for gas turbine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a long life suction filter unit for a gas turbine which is an efficient suction filter unit not to deteriorate power generation output and enables filter replacement at regular inspection of the gas turbine which is mandated to be performed once a year. <P>SOLUTION: In the suction filter unit 5 for the gas turbine provided with a dust filter of a plurality of stages, the dust filter is composed of three stage arrangement of 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 25-35 m<SP>2</SP>/unit, filtering material of 10-70% filtering efficiency in relation to 0.3 μm diameter particles is arranged in a layer of the upstream side in the air flow direction, filtering material of 99.97% filtering efficiency in relation to 0.3 μm diameter particles is arranged in a layer of a downstream side in the air flow direction, and pressure drop at a time of flow rate 50 m<SP>3</SP>/minute is maintained in 15-45 mmAq. <P>COPYRIGHT: (C)2007,JPO&INPIT

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 Patent Document 1, this filter unit e is a two-stage type consisting of a coarse filter f made of a filter material of a take-up type band-like glass fiber and a medium performance filter g in which an ion exchange fiber filter is folded. It is configured. 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.
JP-A-5-106464

  In order to meet the above-mentioned demands, the present inventors have proposed a four-stage type of panel type demister, take-up belt type or windsock type prefilter, box type medium performance filter, and box type high performance filter. There is a problem that the size of the 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 Laid-Open 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. In addition, 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 the 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.

In order to solve the above problems, the high performance filter unit for gas turbine intake of the present invention is a gas turbine intake filter unit in which a plurality of dustproof filters are provided. , A panel type demister, a take-up band type or wind-flow type pre-filter, and a high performance filter for gas turbine intake. The high performance filter for intake of the gas turbine has a low efficiency filter medium from the upstream side in the air flow direction. And high-efficiency filter media are closely stacked, the filter media area of each of these filter media is 25-35 m ² / unit, the upstream layer with respect to the air flow direction, the particles with a particle size of 0.3 μm Te arranged filter media 10% to 70% of filtration efficiency, arranged filter media 99.97% filtration efficiency for particles having a particle diameter of 0.3μm is the layer of the downstream side, of the air flow 50 m ³ / min Characterized in that the pressure loss was 15~45mmAq of. In addition, it is preferable that the said pre filter is a windsock type | mold and a filter medium area is 2-8 m < ² > / unit.

  As described above, according to the gas turbine intake filter unit of the present invention, for example, it is only necessary to replace the filter at the time of a regular inspection once a year by law, so that maintenance work such as filter replacement and compressor cleaning is reduced. Is done. In addition, since a high-performance filter such as a HEPA filter is used, the output of the gas turbine can be reduced due to adhesion of atmospheric dust. In addition, the intake filter unit is compact and space-saving is achieved, and furthermore, the volume of waste such as used filters can be reduced because the filter can be reduced by three stages and one stage compared to a four-stage filter. .

  The panel 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 1 to 10 mmAq. The demister is characterized by low pressure loss, that is, low ventilation resistance and high filtration efficiency with respect to water droplets, and when dirty, it can be reused by removing it from the frame and washing. Of course, as the panel type demister, a refraction type blade type eliminator or the like that prevents rainwater from entering 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 4 to 8 mmAq, the filtration efficiency (JIS 15 type, 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. However, the shape is not limited to this, and any shape may be used as long as the filter medium area can be made as desired. In general, this streamer-type prefilter has a filter medium with a thickness of 10 to 25 mm, a dry nonwoven fabric made of organic fibers such as polyester and acrylic, an average fiber diameter of 20 to 60 μm, a basis weight of 300 to 600 g / m ² , and a wind speed of 2 The pressure loss at 5 m / s is 2 to 8 mmAq, the efficiency (JIS 15 type, weight method) is 60 to 90%, the filter medium area is 2 to 8 m ² / unit using this filter medium, and the external dimensions are vertical 592 mm × A horizontal pre-filter having a horizontal width of 592 mm and a depth of 500 mm was obtained. 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 performance of this filter is such that the pressure loss is 2 to 8 mmAq when the air volume is 50 m ³ / min, the efficiency (JIS 15 type, weight method) is 60 to 90%, and the dust holding capacity is 1000 to 4000 g / unit.

The high-performance filter 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. As a high-efficiency filter medium, 90-99. It is preferable to use one having a filtration efficiency of 99%. 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. In addition, as the low efficiency filter medium, it is preferable to use a filter having a filtration efficiency of 10 to 70% with respect to particles having a particle diameter of 0.3 μm. This is because if it is less than 10%, the burden on the high-efficiency filter medium on the downstream side becomes large, and if it exceeds 70%, the filter medium is clogged quickly. 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 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 5 to 45 mmAq 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 or polyethylene terephthalate, and the filter medium is folded in a zigzag manner. Was inserted into a high-performance filter having a filter medium area of 25 to 35 m ² / unit and outer dimensions of vertical 610 mm × horizontal 610 mm × depth 290 mm. If the area of the filter medium is less than 25 m ² / unit, the pressure loss becomes high 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 preferably 25 to 35 m ² / unit. The performance of this filter is 15 to 45 mmAq in pressure loss when the air volume is 50 m ³ / min, 90 to 99.99% in efficiency (0.3 μm DOP), and 1000 to 3000 g / unit in dust holding capacity.
Select a filter medium area of 25 to 35 m ² / unit and a normal one (21 m ² / unit) that reduces the load of the downstream high-efficiency filter medium for the upstream low-efficiency filter medium. A filter medium having a filtration efficiency of 10 to 70% is selected with respect to 0.3 μm particles, and the filter medium area 25 to 25 so that pressure loss does not increase due to dust passing through the low-efficiency filter medium on the upstream side to the high-efficiency filter medium on the downstream side. A high-efficiency filter medium having a filtration efficiency of 90 to 99.99% with respect to particles having a particle size of 0.3 μm, for example, is selected and arranged so as to be as large as 30 m ² / unit and prevent contamination of the air compressor. I made it. By closely overlapping the low-efficiency filter medium and the high-efficiency filter medium, a large area of the filter medium can be folded into the filter frame without increasing the thickness.
In addition, although the pressure loss at the start of use of the gas turbine increases and the initial power generation output decreases, the compressor does not get dirty, so the gas turbine output does not decrease throughout the year. On the other hand, in the case where the box-type high performance filter is not provided on the most downstream side, the pressure loss at the start of use is low. Since the compressor is contaminated, the power generation output begins to decrease, and as a result, the predetermined output of the gas turbine provided with the box-type high performance filter is lowered halfway.

  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 a casing 1 connected to an intake duct of a gas turbine (not shown), harmful substances such as dust harmful to the continuous operation of the gas turbine are shown. Is removed from the intake air, a three-stage filter unit 5 including a panel type demister 2, a winding band type or blown type prefilter 3, and a high performance filter 4 of the present invention is provided.

  The demister is made by sealing and fixing Saran fiber (Saranlok, registered trademark) in a metal frame, with a rated wind speed of 2.5 m / s, a pressure loss of 3 mmAq, and a filtration efficiency (JIS8, weight method) of 28%. In the casing 1, 16 pieces (length: 610 mm × width: 610 mm × thickness: 35 mm) were installed in the casing 1 (4 rows and 4 stages).

As a pre-filter, the winding belt type has a filter medium with a thickness of 50 mm, a material of glass fiber, an average fiber diameter of 30 μm on the inflow side and a density gradient of 20 μm on the outflow side, and efficiency (JIS 15 types, weight method) of 80%. The performance of the filter using the filter is a self-winding type with a pressure loss of 6 mmAq and a dust holding capacity of 1000 g / m ² at a wind speed of 2.5 m / s, and with ^two external dimensions of 1200 mm in the casing 1 Installed. For the streamer type, the filter medium is a polyester fiber having an average fiber diameter of 35 μm bonded with a vinyl chloride resin to a thickness of 15 mm, a basis weight of 300 g / m ^2, and a pressure loss of 5 mmAq at a wind speed of 2.5 m / s. A filter medium having an efficiency (JIS 15 type, weight method) of 80% was fixed with six folding metal frames to obtain a filter medium area of 4 m ² / unit, outer dimensions of 592 mm × width 592 mm × depth 500 mm. The performance of this filter is that the pressure loss is 5 mmAq when the air volume is 50 m ³ / min, the efficiency (JIS 15 type, weight method) is 80%, the dust holding capacity is 2800 g / unit, and 16 pieces in the casing 1 (4 rows 4 Step) It was set up.

The high-performance filter is a low-efficiency filter medium (thickness 0.3 mm, basis weight 60 g / m ² , filtration efficiency (0.3 μm DOP) 15%, pressure loss 0.9 mmAq, average fiber diameter 2.0 μm, glass fiber and organic fiber) Wet nonwoven fabric) and a high-efficiency filter medium (thickness 0.4 mm, basis weight 70 g / m ² , filtration efficiency (0.3 μm DOP) 99.97%, pressure loss 28 mmAq glass fiber wet nonwoven fabric with an average fiber diameter of 0.8 μm) They are closely overlapped and folded, and an aluminum foil inclined separator is inserted into a zigzag folded type (box type). The filter has a pressure loss of 33 mmAq, a dust holding capacity of 2000 g / unit, a filtration efficiency (0. 3 μm DOP) 99.97% is obtained. Sixteen (four rows and four stages) having an outer diameter of 610 mm × width 610 mm × depth 290 mm obtained in this manner were installed in the casing 1. In addition, when the high-efficiency filter medium and the low-efficiency filter medium are separately installed in two stages as a 610 mm × 610 mm × 290 mm filter as in the past, the pressure loss becomes as high as 38 mmAq. By closely overlapping the efficiency filter media, the structural resistance is lowered, which can contribute to the reduction of the pressure loss of the filter unit.

  A pre-filter using a take-up band type is Example 1 and a wind-sink type is used as Example 2. Further, without using the demister, the take-up band pre-filter and the high-performance filter The high-performance filter of Conventional Example 1 and Example 1 is a single-layered high-performance filter of Conventional Example 1 and Example 1, which is a two-stage box-type medium-performance filter that removes the high-efficiency filter medium and contains only the low-efficiency filter medium. A box-type medium-performance filter and a box-type high-performance filter, which have four stages, are each configured as a gas turbine intake filter unit as Comparative Example 1, and external air is allowed to flow continuously through these gas turbine intake filter units. Subsequently, the gas turbine output reduction during that period was tested, and the space saving of the installation space was evaluated. The structure of each intake filter unit is shown in Table 1 below, and the test results are shown in Table 2 below.

  As is apparent from the above table, as described in Japanese Patent Application Laid-Open No. 5-106464, the conventional two-stage type of winding strip type pre-filter and box type medium performance filter has a gas turbine for long-time use. Is reduced by about 10%. Further, since the filter is clogged and its life is shortened, it is necessary to replace the filter and clean the compressor 2-3 times a year. In Comparative Example 1, the efficiency of gas turbine output reduction is as high as 99.97%, preventing dust from adhering to the compressor, extending the filter life, and replacing the filter once a year. However, the demister, pre-filter, medium performance filter, and high performance filter are four-stage type, and the installation space for the filter becomes enormous, and the equipment cost increases. On the other hand, in the first embodiment of the present invention, a medium performance filter and a high performance filter can be combined, and in the conventional four-stage type, a filter unit having a length of 3300 mm can be saved at 2300 mm and approximately 1000 mm in space. Since the filtration efficiency is excellent as in Comparative Example 1, it is possible to prevent the dust from adhering to the compressor, and the dust holding capacity is larger than that of Comparative Example 1 due to the low pressure loss, resulting in a longer life of the filter. However, since the prefilter is a take-up belt type and automatic, maintenance inspection of the drive unit is necessary due to the drive device. Further, in the second embodiment of the present invention, the prefilter of the first embodiment is made into a blow-off type, so that the output of the gas turbine can be prevented from being reduced, space saving can be achieved, and maintenance free for 8000 hours or more 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 of conventional gas turbine intake filter unit

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Casing 2 Panel type | mold demister 3 Winding strip | belt-shaped type | mold or a windsock 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 32 Seal material 33 Separator

Claims (2)

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 is in close contact with the low-efficiency filter medium and the high-efficiency filter medium from the upstream side in the airflow direction, and the filter medium area of each of these filter media is 25 to 35 m ² / The filter medium is a base, and the upstream layer with respect to the airflow direction is provided with a filter medium having a filtration efficiency of 10 to 70% with respect to particles having a particle diameter of 0.3 μm, and the downstream layer has a particle diameter. arranged filter medium 0.3 [mu] m 99.97% filtration efficiency for particles, the filter for a gas turbine inlet air, characterized in that the pressure loss when the air volume 50 m ³ / min was 15~45mmAq Knit. ^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.

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