RU2814352C1 - Polyfunctional plate heat exchanger - Google Patents

Abstract

FIELD: heat power engineering.

SUBSTANCE: invention relates to heat engineering and can be used in plate heat exchangers for utilization of heat of waste gases and liquids. In polyfunctional plate heat exchanger containing vertical and horizontal channels for cooled and cooling medium, in vertical channels there are complex cleaners, which are vertical baskets with a perforated shell made of stainless material, which length and height are determined by the corresponding dimensions of the vertical channels mounted on the support brackets attached to the lower tube plate, each basket on the sides is equipped with turbulators made in the form of rectangular petals arranged in a staggered order with an inclination at angle of 45° towards flow movement in vertical channels, cavities of baskets are filled with pumice granules made from metallurgical slag with basicity modulus M>1 and granule diameter from 5 to 10 mm, at the top of the vertical channels, above each basket, flushing water distributors are installed, which are pipes perforated from below, connected to a manifold and a flushing water pipeline equipped with a shut-off device, and in the gas line of the cleaned gas there is a drain connection of flushing water.

EFFECT: higher efficiency and reliability of polyfunctional plate heat exchanger.

1 cl, 5 dwg

Description

The present invention relates to heat power engineering, namely, to heat exchange equipment and can be used to recover heat from waste gases and liquids, namely, to recover heat from flue gases of boiler units, industrial furnaces, and ventilation emissions.

A plate heat exchanger is known, including a casing in which a package of heat exchange plates is placed, which form the first spaces (channels) between the plates for the first (cooling) medium (for example, air) and the second spaces (channels) between the plates for the second (cooled) medium. The casing is equipped with tube plates and covers, in which inlet and outlet openings (pipes) are arranged for entering the plate heat exchanger and exiting the heated and cooled media from it, and the heat exchange plates are connected to the casing, tube plates and covers through seals [RF Patent No. 2426965, μl F 28 D 9/00, μl F 28 G 13/00, 2009].

The main disadvantage of the known plate heat exchanger is the absence of devices in the channels that turbulize coolant flows and the impossibility of purifying waste gases from harmful impurities, which reduces the rate of heat exchange between coolants, the environmental characteristics and efficiency of the device.

Closer to the proposed invention is a plate air heater containing a package of flat plates coated with an anti-corrosion coating with turbulizing protrusions (turbulizers), forming channels between each other for heat-exchanging flows of gas and air [A. With. USSR No. 1575062, Mkl. F 28 D9/02, 1990].

The main disadvantages of the known plate air heater are the complexity of its design, due to the need to manufacture plates with turbulent protrusions, the difficulty of cleaning the surfaces of these plates from contaminants (dust particles, ash, soot, etc.) when operating a heat exchanger with dusty coolants, and the inability to clean waste gases from harmful impurities, which reduces its economic and environmental efficiency.

The technical result to which the proposed invention is aimed is to increase the economic and environmental efficiency of a multifunctional plate heat exchanger.

The technical result is achieved by the fact that the proposed multifunctional plate heat exchanger contains a horizontal casing made in the shape of a rectangular parallelepiped, the top, bottom and ends of which are made in the form of upper and lower tube sheets with rectangular holes and two end tube sheets with rectangular holes, a package is placed inside the casing , consisting of heat exchange plates installed between the upper and lower tube sheets and end tube sheets with the formation between themselves of vertical gas channels (cooled medium) communicating with the holes and horizontal air channels (cooling medium) communicating with the holes of the end tube sheets, while , from the ends, top, bottom, the casing is closed by end, top and bottom covers, which are equipped with inlet and outlet pipes, and in the vertical gas channels there are complex purifiers, which are vertical baskets with a perforated shell made of stainless material, the length and height of which are determined correspondingly sized vertical gas channels installed on support brackets attached to the lower tube plate, each basket is equipped with turbulators on the sides, made in the form of rectangular petals, placed in a checkerboard pattern with an angle of 450 in the direction of the gas flow in the channels, the cavity of the baskets filled with pumice granules made from metallurgical slag with a basicity modulus M>1 and a granule diameter from 5 to 10 mm, at the top of the gas channels above each basket there are flush water distributors, which are pipes perforated at the bottom, connected to a flush water collector and a flush water pipeline, equipped with a shut-off device, and a flushing water drain fitting is located in the purified gas pipeline.

The proposed multifunctional plate heat exchanger (MPHE) is shown in Fig. 1–5 (Fig. 1,2 – general view and sections, Figs 3 – 5 complex cleaner, its unit and section).

The PFPTO consists of a horizontal casing 1, made in the form of a rectangular parallelepiped, the top, bottom and ends of which are made in the form of upper 2 and lower tube sheets 3 with rectangular holes 4 and two end tube sheets 5, 6 with rectangular holes 7, inside the casing 1 is placed package 8 consisting of heat exchange plates 9 installed between the upper and lower tube sheets 2 and 3 and the end tube sheets 5 and 6 with the formation of vertical gas channels (cooled medium) 10 between them, communicating with holes 4 and horizontal air channels (cooled medium) 11, communicating with the holes 7 of the end tube plates 5 and 6, while at the ends, top, bottom, the casing 1 is closed with end caps 12, 13 and top and bottom covers 14, 15, which are equipped with inlet and outlet pipes 16, 17 and 18 , 19, respectively, and in the vertical channels 10 there are complex cleaners 20, which are vertical baskets with a perforated shell 21 made of stainless material, the length and height of which are determined by the corresponding dimensions of the vertical channels 10, installed on support brackets 22 attached to the lower pipe board 3, each basket 20 is equipped with turbulators 23 on the sides, made in the form of rectangular petals, placed in a checkerboard pattern with an angle of 450 in the direction of the gas flow in channels 10 (up), the cavities of the baskets 20 are filled with pumice granules 24 made from metallurgical slags with a basicity modulus M>1 and a granule diameter from 5 to 10 mm, at the top of the channels 10 above each basket 20 there are wash water distributors 25, which are pipes perforated from below, connected to a wash water collector 26 and a wash water pipeline 27, equipped with a shut-off valve device 28, and in the purified gas pipeline there is a flushing water drain fitting (in Fig. 1–5 not shown).

The operation of the proposed PFPHE is based on the use of granulated slag pumice 24 and turbulizers 23, made in the form of rectangular petals, placed in a checkerboard pattern with an angle of 450 towards the movement of the gas flow in channels 10, as an adsorbent for harmful components of waste gases. made from basic metallurgical slags, it is a material with a highly porous mechanically strong structure (compressive strength up to 2.7 MPa), consisting of calcium oxide, silicon oxide, aluminum oxide and partly magnesium oxide (CaO, SiO2, Al2O3, MnO) c basicity module M>1 [Building materials. Directory. Ed. Boldyreva A. S. et al. – M.: Stroyizd., 1989, p. 423; Domokeev A.K. Construction materials. – M.: Higher. school, 1989, p. 163]. The high value of the basicity modulus gives the slag pumice granules 24 basic properties that allow them to adsorb on their surface substances with acidic properties, which include harmful impurities that are present in exhaust gases (NOx, SOx, COx), and the high porosity of their structure allows the use slag pumice granules as an effective sound-absorbing material [V. N. Bogoslovsky and others. Heating and ventilation, Part II.–M.; Stroyizdat, 1978, p. 391]. In addition, based on their composition, slag pumice granules are resistant to the corrosive effects of acidic components of waste gases, are widely available and cheap. The use of turbulators 23, made in the form of rectangular petals, placed in a checkerboard pattern with an inclination at an angle of 450 towards the movement of the gas flow in the channels 10 allows you to direct the gas flow into the cavity of the basket 20 filled with granules of blast furnace slag and turbulize the gas flow, which simultaneously ensures its cleaning and increases the rate of heat transfer.

The installation of complex purifiers 20 in the vertical channels 10 is carried out with the end cover 12 removed on the support brackets 22, on which the position of the baskets 20 is fixed in such a way as to ensure the required open cross-section of the channels 10 for the passage of waste gases and the petals of the turbulators 23 do not touch the heat exchange plates 9 (clamps not shown in Fig. 1–5). Next, box 1 is connected to the end cover 13 and the upper and lower covers 14 and 15 (fastening points are not shown in Fig. 1–5).

The proposed PFPTO works as follows. The cooled medium, for example, flue gases, enters through the inlet pipe 18, is distributed through the holes 4 of the tube sheet 2 and is directed into the vertical gas channels 10 of the package 8, when moving through which the flue gases are cooled as a result of heat exchange to a given temperature through heat exchange plates 9 with a cooling environment, for example, outside air moving through horizontal air channels 11, after which the cooled flue gases are removed from the heat exchanger through the holes 4 of the tube sheet 3 and through the pipe 19. At the same time, air (cooling medium) is supplied from the side through pipe 16 and air holes 7 into the horizontal air channels 11 of package 8, and is heated from t0 to tG as a result of heat exchange through heat exchange plates 9 with cooled gases moving through vertical channels 10, after whereby the heated air through the air holes 7 of the tube sheet 6 enters the pipe 17, from where it is supplied to the consumer. At the same time, the petals of the turbulators 23, connected to the perforated basket 21 of the complex purifiers 20 at an angle of 450 relative to the plane of their lateral surface, direct the gas flow into the volume of slag pumice granules, where it is purified from harmful gaseous (NOx, SOx, COx) and solid impurities, turbulize it, which at the same time makes it possible to purify gases from harmful components and increase the rate of heat transfer between gas and air flows. In addition, the presence of turbulators 23 located in the core of the flue gas flow ensures turbulence of the entire flow reaching the walls of the channels 10 themselves, which prevents the deposition of solid impurities on them and further increases the efficiency of heat transfer and the effective operation life of the PFPHE.

When the activity of granules 24 decreases, they are subjected to regeneration. The regeneration process consists of cleaning the surface and pores of slag pumice granules 24 from fine particles and adsorbed molecules of harmful impurities and is carried out by washing the granules 24 from the wash water distributors 25 with water supplied through the wash water collector 26 connected to the wash water pipeline 27 with the shut-off device 28 open. and removing dirty water from baskets 21 through pipe 18 and the flushing water drain fitting in the purified gas pipeline (not shown in Fig. 1–5).

Replacement of spent granular slag is carried out by removing the cover 12 and removing the baskets 21, in which the spent granules 24 are replaced with fresh ones and then installing the filled baskets 21 into the vertical channels 10 and the cover 12 (attachment points in Fig. 1–5 are not shown).

The dimensions of the PFPHE, the total volume of slag pumice granules 24, the number of baskets 21, their length, height and width, the width of gas and air channels 10, 11, the flow rate of flushing water are determined depending on the power of the heat exchanger and the required degree of purification of waste gases.

The mutual perpendicular arrangement of the air 10 and gas 11 channels in the PFPHE allows the heat exchange process to be carried out according to a cross pattern of coolant movement, which provides a fairly high driving force for heat transfer and is widely used in air heaters for steam generators [Thermal calculation of industrial steam generators. Ed. Chastukhina V.I. – Kyiv: Vishcha School, 1980, p. 50], makes it possible to significantly simplify the design of covers 12, 13, 14, 15 (the internal cavity of the covers does not need to be divided by partitions into air and gas channels) and reduce their weight, significantly reduce aerodynamic resistance compared to known plate heat exchangers with cover designs for direct flow and counterflow flow patterns for coolants.

Thus, the design of the proposed PFPHE makes it possible, by installing complex purifiers equipped with petal turbulators and ensuring cross-motion of heat exchanging media in the channels, to increase its efficiency and reliability compared to known plate heat exchangers.

The work was carried out within the framework of the development program of the Federal State Budgetary Educational Institution of Higher Education "Southwestern State University" of the project "Priority 2030".

Claims (1)

A plate heat exchanger with inserted turbulators, containing a casing equipped with tube plates and covers, inlet and outlet pipes for the inlet and outlet of heat exchanging media, in which is placed a package consisting of heat exchange plates with turbulators, which form channels for the cooled and cooling medium and are connected to the casing , tube sheets and covers, characterized in that the casing is made horizontal in the shape of a rectangular parallelepiped, the upper, lower and end tube sheets are made with rectangular holes for the cooling and cooled medium, the channels of the cooled medium are connected to the holes of the upper and lower tube sheets and are directed vertically, the channels of the cooling medium are connected to the rectangular holes of the end tube plates and are directed horizontally; complex purifiers are installed in the vertical channels, which are vertical baskets with a perforated shell made of stainless material, the length and height of which are determined by the corresponding dimensions of the vertical channels, installed on support brackets attached to the lower tube plate, each basket is equipped with turbulators on the sides, made in the form of rectangular petals, placed in a checkerboard pattern with an angle of 45° in the direction of flow in vertical channels, the cavities of the baskets are filled with pumice granules made from metallurgical slag with a basicity modulus M>1 and granule diameter from 5 to 10 mm, at the top of the vertical channels above each basket there are flushing water distributors, which are pipes perforated from below, connected to a collector and a flushing water pipeline equipped with a shut-off device, and in the purified gas pipeline there is a flushing drain fitting water.