CN2104383U - U-pipe afterheat boiler - Google Patents

Abstract

The utility model discloses a U-shaped pipe waste heat boiler for recovering the heat of the high-temperature technology gas of the outlet of a secondary reforming boiler in a large synthetic ammonia device and comprises a barrel body and a pipe plate on the cylinder body. The pipe plate is provided with a spherical sealing head and a U-shaped pipe bundle fixed on the pipe plate is arranged in the barrel body. The bend pipe section of the U-shaped pipe bundle is positioned on the lower part of the gas charging pipe of the technology gas and through a heat insulating plate is isolated from the gas charging pipe of the technology gas. The U-shaped pipe waste heat boiler can fundamentally solve the problem of the pipe explosion of the waste heat boiler and has the characteristics of simple structure and safety.

Description

U-pipe afterheat boiler

The utility model relates to a kind of boiler, particularly a kind of waste heat boiler that is used for large-scale synthetic ammonia installation recovery high-temperature technology heat.

In large-scale synthetic ammonia installation, adopt vertical U type pipe waste heat boiler to reclaim the heat of secondary reformer outlet high-temperature technology gas.This boiler has compact conformation, big, the series of advantages such as the heat pipe hot expansibility is good, tube sheet good operation conditions of exerting oneself., after this waste heat boiler puts into operation, at U type pipe bend loss pipe explosion accident taking place again and again, causes a whole set of synthetic ammonia installation to stop production.According to statistics, the large-scale synthetic ammonia installation of three covers that China introduces from French Heurtey company is since 1978 go into operation operation, waste heat boiler generation pipe explosion accident adds up to more than 20 time, and each booster only raw material direct losses reaches 400,000 yuan, and loss of income is all more than 1,000,000 yuan; If change the tube bank of U type, then each is worth 250,000 dollars, causes serious economy loss to chemical fertilizer industry.

The purpose of this utility model is to overcome the problem that above-mentioned boiler exists, and proposes a kind of bend loss heat-insulating type U type pipe waste heat boiler, can fundamentally solve waste heat boiler booster problem, has simple in structure, safe and reliable characteristics.

Measuring, the basic reason of prior art U type pipe waste heat boiler generation booster is: when steam water two phase flow passes through U type pipe bend loss, separation of two very easily takes place under the double action of centrifugal force and gravity, and U type pipe bend loss is subjected to directly washing away of import high temperature and high speed process gas flow with exactly standing in the breach, U type pipe bend loss heat intensity is very high, cause the laminated devices heat transfer deterioration takes place in the pipe, thereby cause that violent rising of inside tube wall temperature causes pipe explosion accident.

Therefore, as long as eliminate the phenomenon of U type pipe bend loss generation laminated devices heat transfer deterioration, can solve the booster problem of U type pipe waste heat boiler.

Fig. 1 is a structure principle chart of the present utility model.

Fig. 2 is the structure chart of ring baffle plate of the present utility model (4).

Fig. 3 is the structure chart of circular deflection plate of the present utility model (4a).

Fig. 4 is the structure chart of water distributing plate of the present utility model (11).

With reference to the accompanying drawings structural principle of the present utility model and operation principle are described in detail.

The utility model comprise a cylindrical shell (6) and on tube sheet (9), dispose dome head (13) on the tube sheet (9); The downside of cylindrical shell (6) disposes process gas air inlet pipe (3), the upside of cylindrical shell (6) disposes process gas subordinate line escape pipe (7) and process gas escape pipe (8), be furnished with the U-shaped tube bank (5) that is fixed on the tube sheet (9) in the cylindrical shell (6), be installed with circular deflection plate (4a) and ring baffle plate (4) in the U-shaped tube bank (5); The bend loss of U-shaped tube bank (5) is positioned at the bottom of process gas air inlet pipe (3) and isolated by the thermal insulation board (1) and the process gas air inlet pipe (3) that are through in the U-shaped tube bank (5), disposes annular gas distributor (2) between next stage ring baffle plate and thermal insulation board (1); Volume in the dome head (13) is divided into hydroecium and steam chest by dividing plate (12), the hydroecium side disposes saturation water import (14), the middle part is provided with porous water distributing plate (11), the peripheral opening diameter of porous water distributing plate (11) is greater than the interior opening diameter that encloses, to guarantee the uniformity of water distribution in each U-shaped tube bank, the steam chest side disposes steam water interface outlet (10).

When using the utility model, process gas enters cylindrical shell (6) by process gas air inlet pipe (3) through annular gas distributor (2) and washes away U-shaped tube bank (5), with the working medium in the U-shaped tube bank of heat transferred (5), main flow flows out through process gas escape pipe (8), and a small amount of process gas flows out through subordinate line escape pipe (7); Saturated feedwater flows into hydroecium by saturation water import (14), after distributing, porous water distributing plate (11) enters U-shaped tube bank (5), absorption technique gas heat in the flow process in U-shaped tube bank (5), form the steam-water twin phases mixture, enter again steam chest, and flow out steam chest through steam water interface outlet (10).

This shows, because U type tube bank bend loss of the present utility model is positioned at process gas air inlet pipe bottom, and blocks with thermal insulation board, makes it not washed away by process gas, the level that can make the thermic load of bend loss very little, the wall temperature maintenance is close with intraductal working medium, thus pipe explosion accident can not take place.

Among the figure, (1) is that thermal insulation board, (2) are that annular gas distributor, (3) are that process gas air inlet pipe, (4) are that ring baffle plate, (4a) are that circular deflection plate, (5) are that U-shaped tube bank, (6) are that cylindrical shell, (7) are that process gas subordinate line escape pipe, (8) are that process gas escape pipe, (9) are that tube sheet, (10) are that steam water interface outlet, (11) are that porous water distributing plate, (12) are that dividing plate, (13) are that dome head, (14) are the saturation water imports.

Claims (2)

1, a kind of U type pipe waste heat boiler, comprise a cylindrical shell (6) and on tube sheet (9), dispose dome head (13) on the tube sheet (9), feature of the present utility model is, be furnished with the U type tube bank (5) that is fixed on the tube sheet (9) in the cylindrical shell (6), be installed with circular deflection plate (4a) and ring baffle plate (4) in the U type tube bank (5), the bend loss of U type tube bank (5) is positioned at the bottom of process gas air inlet pipe (3) and isolated with process gas air inlet pipe (3) by the thermal insulation board (1) that is through in the U type tube bank (5), dispose annular gas distributor (2) between next stage ring baffle plate and thermal insulation board (1), the middle part of dome head (13) is provided with porous water distributing plate (11).

2, waste heat boiler according to claim 1 is characterized in that, the peripheral opening diameter of said porous water distributing plate (11) is greater than the interior opening diameter that encloses.

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