JPS5966612A - Dust adhering preventive device in waste heat boiler - Google Patents

Abstract

PURPOSE:To remove or peel off dust easily which is adhered and accumulated on a heat exchanger pipe by a method wherein pipe arranging pitch setting fittings are vertically arranged at the lower end of the bent suspension heat exchanger pipe, a connection shaft is arranged and fixed between the setting fittings and a striking force is applied to the connecting shaft. CONSTITUTION:Pipe arranging pitch setting fittings 12 are vertically arranged at the lower end of the bent heat exchanger pipe 4 through abutment plates 8. Said setting fittings 12 are inserted between projection pieces 13 attached to the connecting shaft 5 and then fixed at the site. There are arranged the fixing shaft 14 and a stopper 15 for preventing a disturbance of pipe arranging pitch in a gas flow direction in the suspended heat exchanger pipe. Dust flowed together with the gas flowing in the heat exchanger plane is, as shown in Fig., processed such that its dust piling S grows along a direction of gas flow A. In turn, a striking force applied to the connection shaft 5 under an operation of the hammer 10 is applied in a direction R perpendicular to the direction A, thus the momentum when the piling S is vibrated off the surface of the heat exchanger pipe becomes high and an efficient dust removal can be performed.

Description

Detailed Description of the Invention In a cement plant, the waste gas discharged from the suspension breheater has a relatively low heat level, but has a huge amount of waste gas, so in order to recover the sensible heat of this waste gas, A heat boiler is provided. The gas contained a large amount of fine powder dust, which adhered and accumulated on the heat transfer tubes of the boiler, inhibiting heat transfer and significantly reducing the performance of the boiler.

Dust attached to the heat exchanger tubes is removed by a combination of a soot blower and a hammering device, but the soot blower has a limited dust removal range due to its structure, and the dust that has adhered to the heat exchanger tubes is dispersed in the form of gold powder particles. When the dust is reattached to the rear heat transfer surface or when the soot blower is activated, the number of dust particles reaching the rear induced blower rapidly increases, causing an overcurrent to flow, causing a trip and halting plant operation. There were drawbacks such as stopping.

In addition, since the soot blower uses compressed air or steam as the injection medium, if the photovoltaic plant is made up of 47'l' of steam generated by the waste heat boiler, the plant efficiency will be reduced.

Furthermore, since conventional hammering devices are installed in the center of the heat exchanger tubes, they cannot be assembled on-site, so the tubes must be integrated at the factory, and as the heat exchanger tubes become larger,
The invention has disadvantages such as difficulty in transportation from the factory to the site, installation on site, and maintenance and inspection.
i, transport and installation of heat transfer i'ii'.

A waste heat boiler that allows easy maintenance and inspection.
.

0-□ □ First, the waste heat boiler incorporated in a conventional cement plant is explained using a gS/diagram.O/ is a waste heat boiler. vinegar/
<7y″″77vh-ta・3 is an induced blower 0
3♂00T discharged from the suspension preheater
- The exhaust gas at 00'C is approximately 260°C in the waste heat boiler.
The dust in the gas discharged from the suspension preheater j, which is cooled to 0 and flows into the downstream equipment via the induced blower 3, is! It is in the form of a fine powder, with 9j% of it being less than μ.
It has a strong agglomeration property, and for example, if it is left unused after passing through the gas (the dust removal device is not activated), it will adhere and accumulate over the entire circumference of the hanging heat exchanger pipe in a few hours, causing a problem in the heat transfer. Due to the dirt on the heating surface, the heat transfer coefficient decreases significantly, making it impossible to obtain the desired boiler performance.At the same time, the gas passage 75E narrows due to the adhesion of dust, which increases the gas flow velocity and causes loss of ventilation inside the boiler. 9.45 Dust attached to the heat transfer tube group is generally removed by a soot blower, but due to the structure The dust removal range is limited, it is impossible to completely remove °C dust over the entire surface of the heat exchanger tube, and the locally removed dust becomes powder-like.
After that, it is entrained by the gas flow and then redeposited on the heat transfer surface)
There are drawbacks such as □, but to compensate for this, a hammering device is used in conjunction with 0°6 Figure 7. Part J [is an example of a hanging type heat exchanger pipe (used in conventional hanging type heat exchanger pipes). 10 collision energy is connected via intermediate shaft 9! to communicate. Is the connecting shaft j welded and fixed to the support plate O? By transmitting impact energy to each heat transfer tube through the contact plate r and causing it to vibrate,
The attached dust is peeled off, naturally falls into a hopper 16, and is discharged by a conveyor/7. Further, the glasses-shaped partition 7 is provided to prevent the tube arrangement □ of the heat transfer tubes from being disturbed in the gas flow direction.

With conventional hammering devices, the connecting part tends to be installed in the center of the heat exchanger tube, making on-site assembly impossible and requiring factory installation. When the heat transfer tubes are converted into a factory sonic unit, if the heat transfer tubes become larger, transportation restrictions may occur, such as weight and dimensions when attached. Furthermore, since the connecting part is located in the center of the heat transfer tube, dust tends to adhere and accumulate, and since people cannot get close to the connecting part, repairs and inspections may be difficult. The biggest drawback is that it cannot be done.

Next, embodiments of the present invention will be explained with reference to FIGS. 3 to 9. □Pipe arrangement pitch setting fitting/2 is installed vertically at the lower end of the heat transfer tube through the contact plate ♂・Connection shaft! Insert the above-mentioned foot fittings / □ between the protrusion pieces / 3 attached to J and fix them at the J site. □Fixed shaft/4t to prevent disturbance of tube arrangement pitch in the gas flow direction of hanging heat transfer tubes
And, o71r is provided with a stopper is.O, @Figures 6 to 9 show the case of base pattern arrangement, but 4. of staggered arrangement. 'o' shown in the 1st θ to 1st fig.
□Next, the functions and effects of this boiling device will be explained. □・.

□ The gas flowing within the heat transfer surface is uniform because there are no injection pipes of the soot blower, connecting shaft 1 of the normalizing equipment, support plate's top, or spacing piece in the passage. The flow pattern can be realized. In this way, as the gas flows along the heat transfer surface, the dust S deposits S grows in the direction along the gas flow direction A, as shown in Figure 1.・Near, connecting shaft! The impact given by Nohejima 10 to
It is given by turning the finger □, therefore, the heat transfer tube 8tS is
The moment when a dropout is ``shaken'' from the surface becomes larger, and □ more efficient removal of prisoners □ is carried out.

□-Also, set the height of the lower end of each □m pipe bend.
□'72 drawing daytime drawing wS'lt If the lower end height of the bend is the same (
70 and FIG. 1/), it is extremely effective in preventing the phenomenon of bridge formation due to dust.

No./! The figure shows the relationship between the impact position of the hammering device between the upper and lower sides of the hanging heat exchanger tube and the acceleration induced in the heat exchanger tube.According to the experiments conducted by the inventors, the comparison was made with the same impact energy. Then, between the center and the lower end of the tube, the force of the blow that was applied to the lower end (curve υ shown by the solid line in the figure) is
Compared to when hitting the center (the curve shown by the broken line in the figure?),
It was found that the acceleration generated in the heat exchanger tube was large, and it was confirmed that the dust removal effect was large.

In the present invention, the pipe arrangement pitch setting metal fittings are completely vertically installed at the lower end of the bend of the hanging heat exchanger tube, a connecting shaft is interposed between the setting metal fittings, and the connecting shaft is fixed by 7Δ, and a water impinging force is applied to the connecting shaft. By soundly vibrating the heat exchanger tube, the dust that tries to accumulate on the heat exchanger tube can be peeled off and dropped uniformly over the entire length of the tube, so that the dust that tries to accumulate on the heat exchanger tube can be peeled off and fallen evenly over the entire length of the tube. This makes it possible to reduce the frequency of soot blower use and the number of soot blowers installed, without any negative impact on
It also provides a sound effect that reduces transportation costs, construction costs, and operating power costs.

The device aspect of the present invention is made of cement clinker-8, ooo
An overview of an example in which the present invention was used for heat recovery of waste gas from a suspension preheater of 1,000 yen will be described.

The shape of this waste heat boiler is height 7J-', width 'I-', 3m.
, depth/gm, and two large hanging heat exchanger tubes are installed in parallel. With this boiler, the waste gas is cooled from about 3 and θ0C to about Jθ0C at the boiler inlet, and the temperature is 3!θQ at no.
0 tons of C steam was recovered per 4 hours.

This waste heat boiler is equipped with the dust removal device of the present application, and although the soot blower has not been used at all for about 3 months since the start of operation, no dust was observed at all. performance has been maintained, and the main line equipment has achieved good operational results.

[Brief explanation of the drawing]

Figure 1 is a plant layout diagram showing how the waste heat boiler is used.
Figure 2 is a front view of a conventional waste heat boiler dust adhesion prevention device, Figure 3 is its side view, Figure 3 is an enlarged sectional view of its main parts, and Figure 5 is the main parts of Figure 2. FIG. 6 is a front view of one embodiment of the device of the present invention, FIG. 7 is a side view thereof, FIGS. Figures 10 and 72 are enlarged 1/2 enlarged views of essential parts of different embodiments of the uninvented device, and Figure 1/ is part 1 of Figure 1θ: (from ill u41) Fig. 73 is a view from all sides of the part of Fig. 72, Fig. 1 is an explanatory diagram of the arrangement of heat transfer tubes of unit U, Fig. 1 is a view of the main white side of the device. It is a graph diagram for explaining the characteristics. /11. Waste heat boiler, G01. Hanging type corrugated tube type heat transfer tester,
! 01. connection shaft, 610. a support plate, and 08. Our board, Wa 6
1. Inner '1 (IIs/θ41. Hammer, /2., Pipe arrangement pitch setting fitting, i3., Protrusion, /R,., Fixed shaft, /!... Stopper 0 Applicant: Kawasaki Heavy Industries, Ltd.) Co., Ltd. U iJU Concentration Procedures Amendments Director of the Patent Office Kazuo Wakasugi, 3, Relationship with the ILI Correction Case Patent Applicant Address 3-chome, Raiyosaki-cho, Chuo-ku, Kobe City/Number/No. Name (θ22) Name of Kawasaki Heavy Industries Co., Ltd. Agent Address: Kobe 11j Chuo-ku, Aioi-cho, Gu-chome, No. Otsu Contents of correction ■: 1/9! Revise the diagram on the attached sheet. 63- ゝ--y- ' to

Claims (1)

[Claims] In a waste heat boiler that is constructed with hanging type heat exchanger tubes, the tube arrangement pitch setting fittings are all vertically installed at the lower end of the bend of the heat transfer tubes, and a connecting shaft is interposed between the setting fittings. A waste heat boiler with dust cover is characterized in that the heat exchanger tubes are vibrated by applying full impact force to the connecting shaft. 1 prevention device.