CN203370463U

CN203370463U - Flue gas denitrator of coal fired boiler

Info

Publication number: CN203370463U
Application number: CN201320373650.1U
Authority: CN
Inventors: 谢海天; 谢承坤
Original assignee: ANHUI LONGSHAN ENVIRONMENT ENGINEERING Co Ltd
Current assignee: ANHUI LONGSHAN ENVIRONMENT ENGINEERING Co Ltd
Priority date: 2013-06-27
Filing date: 2013-06-27
Publication date: 2014-01-01
Anticipated expiration: 2023-06-27

Abstract

The utility model relates to a flue gas denitrator of a coal fired boiler. The flue gas denitrator comprises a barrel body (1) and a thermal insulation layer on the barrel body (1), wherein two ends of the barrel body (1) are connected with a flue gas inlet pipe (5) and a flue gas outlet pipe (6), and the flue gas inlet pipe is provided with an expansion joint (7) and a flange (8). The flue gas denitrator is characterized in that the barrel body (1) is internally provided with at least three layers of plate type catalyst layers (2), the plate type catalyst layers (2) are parallel crapy V2O5 catalyst plates vertically loaded on a stainless steel grid the porosity of which is more than or equal to 80%, the distance between the catalyst plates is more than or equal to 5mm, steam soot blowers (3) are arranged below the first catalyst layer and the second catalyst layer at least, and an ammonia gas ejector (4) is arranged on the section of the flue gas inlet pipe (5). The denitrator is a bypass and is connected in front of a boiler flue heat exchanger (10) in series, and the high temperature of the initial flue gas is used for reduction and denitration. According to the flue gas denitrator, the number of layers of the catalyst can be set according to the denitration requirement, the flue resistance is reduced by regulating the plate distance, dust blocking is avoided, the denitration efficiency in one denitrator is more than or equal to 80%, so that the GB13223-2003 standard code is met.

Description

A kind of fire coal boiler fume denitrator

One, technical field

The utility model relates to a kind of flue purifier of boiler, specifically a kind of fire coal boiler fume denitrator.

Two, background technology

Reduction denitration method (SCR), Here it is aerial O are used in the fire coal boiler fume denitration mostly ₂(oxygen) and catalyst vanadic anhydride (V ₂o ₅) effect under, with reducing agent (NH ₃), by the NO in flue gas _xbe reduced into harmless nitrogen (N ₂) and water (H ₂o) a kind of method of denitration.

Reduction reaction formula: 4NO+4NH ₃+ O ₂→ 6H ₂o+4N ₂

The temperature that the SCR method is suitable is 250-400 ℃.

Current V ₂o ₅catalyst is cellular.For improving denitration efficiency, multilayer must be set.Reduce resistance and increase but the multilayer flux is set, the flue gas circulation is not smooth, affects burning smoke efficiency, can only arrange at most at present two-layer, yet two-layer catalyst denitration effect can not meet the regulation of GB13223-2003 " fossil-fuel power plant atmospheric pollutant emission standard ".

Three, summary of the invention

The utility model is for the defect of prior art, aim to provide a kind of efficient fire coal boiler fume denitrator, what is called efficiently completes denitrification process exactly in a denitrator, and technical problem to be solved is to improve the pattern of catalyst to reduce the resistance to flue gas.

This denitrator as shown in Figure 1, comprise that (it is known technology that the equipment of being heated is incubated for heat-insulation layer on cylindrical shell 1 and cylindrical shell 1, therefore not signal in Fig. 1), two ends at cylindrical shell 1 connect flue gas inlet tube 5 and the smoke outlet tube 6 with expansion joint 7 and flange 8, flange 8 is for movable connection, the effect of expansion joint 7 has two, one, increases the intensity of airduct, and the 2nd, the deformation that compensation wind pipe causes because expanding with heat and contract with cold.This denitrator difference with the prior art is at the interior setting of cylindrical shell 1 three ply board formula catalyst layer 2 at least, described board-like catalyst layer 2 be on the stainless steel aperture plate of porosity>=80% vertical the and parallel storing of load be with crisp V ₂o ₅catalyst plates, the gap formed because of gauffer between plate and plate is exhaust gases passes, the not only unimpeded but also anti-obstruction of this flue, distance between plates>=5mm, as shown in Figure 2.Below at least first and second is two-layer (counting from top to bottom) catalyst layer is provided with steam sootblowers 3.Be provided with ammonia injector 4 on the cross section of flue gas inlet tube 5.

This denitrator is connected on the place ahead of chimney heat exchanger 10 on the flue of coal-burning boiler as bypass, as shown in Figure 4.The initial flue gas that contains a large amount of dust that namely boiler 9 burnings generate is through emptying by chimney 14 after heat exchanger 10, deduster 11, air-introduced machine 12, devulcanizer 13 purifications successively again after denitration is processed.The effect of heat exchanger 10 is that the air of boiler 9 is supplied with in preheating by blower fan 15a.

The purpose of layout is to utilize the high temperature of initial flue gas to be reduced denitration like this.Shortcoming is to carry out ash disposal to catalyst layer.

This denitrator compact conformation, floor space is little, is conducive to the flue gas denitrification system design of newly-built and reconstruction boiler and arranges, safe and reliable to operation.The number of plies of catalyst can be set according to the needs of boiler size and denitration, and the size by the adjustable plate spacing to be to reduce flue resistance, this flue can guarantee the unimpeded and anti-dust obstruction of flue gas, can guarantee again the denitration efficiency in a denitrator.This denitrator denitration rate>=80%, the escaping of ammonia≤3%, SO ₂oxygenation efficiency≤1%, can meet the GB13223-2003 standard code.Catalyst is greater than 24000h service life.

Four, accompanying drawing explanation

Fig. 1 is this denitrator structural representation.The flow direction of figure hollow core arrow signal flue gas.

Fig. 2 is board-like catalyst layer top view.

Fig. 3 is the stereogram of board-like catalyst layer.

Fig. 4 is the schematic layout pattern of this denitrator in the boiler flue system.

Five, the specific embodiment

By reference to the accompanying drawings, non-limiting examples is described below.

1, the preparation of board-like catalyst layer, as shown in Figure 2 and Figure 3.

Get the TiO that porosity is 88.5% ₂the stainless steel aperture plate is as carrier, and on it, the vertical and parallel storing of load is with crisp V ₂o ₅catalyst plates, distance between plates 6mm.Some catalyst plates form 180 * 180 * 300mm square, and one deck catalyst is put one.

Get commercially available V ₂o ₅catalyst powder be rolled into the lath that 0.7mm is thick after organic silicon adhesive mixes, before not yet solidifying, mold pressing once, forms the discontinuous gauffer again, after demoulding drying, is to be with crisp V ₂o ₅catalyst plates.

2, the processing of denitrator, as shown in Figure 1.

With ordinary carbon steel processing cylindrical shell 1, flue gas inlet tube 5 and smoke outlet tube 6, external application blanket of glass wool or rock wool heat-preservation.The length and width of the cross section of cylindrical shell 1 and catalyst square adapt.Being reserved with two holes on cylindrical shell 1 sidewall, is the steam-gas inlet of steam sootblowers 3.At pipe 5 and expansion joint 7 and the flange 8 that is connected use that compensation use is arranged on pipe 6.Cylindrical shell 1 and 5 movable connections of pipe, with easy maintenance and replacement catalyst layer 2.

At the interior three ply board formula catalyst layer 2 that arranges of cylindrical shell 1.Catalyst plates between layers has the antarafacial angle, is beneficial to flue gas and fully contacts with catalyst.Below the 1st and the 2nd layer, steam sootblowers 3 is set.

Ammonia injector 4 is set on the cross section of flue gas inlet tube 5.

3, the layout of denitrator in flue system, as shown in Figure 4.

In existing flue system, the place ahead of heat exchanger 10 separates flue with dividing plate, in the place ahead of dividing plate flue upper shed, with de-cigarette device flue gas inlet tube 5, be connected, be connected with smoke outlet tube 6 in the flue upper shed of the rear of dividing plate, make denitrator form a bypass and be connected on flue.

Other layouts in former flue system are constant, as are blower fan 15a, the 15b of boiler 9 air feeds, and after heat exchanger 10, sack cleaner 11, air-introduced machine 12, devulcanizer 13 and the

chimney

14,16 of series connection are the steam house steward.

This reducing agent ammonia is used the liquefied ammonia of gasification, and liquefied ammonia is sent to ammonia injector 4 by blower fan 19 from storage tank 17 after evaporimeter 18 gasifications.

Claims

1. a fire coal boiler fume denitrator, comprise the heat-insulation layer on cylindrical shell (1) and cylindrical shell (1), two ends at cylindrical shell (1) connect flue gas inlet tube (5) and the smoke outlet tube (6) with expansion joint (7) and flange (8), it is characterized in that: at least three ply board formula catalyst layer (2) is set in cylindrical shell (1), described board-like catalyst layer (2) be on the stainless steel aperture plate of porosity>=80% vertical the and parallel storing of load be with crisp V ₂o ₅catalyst plates, distance between plates>=5mm; Be provided with steam sootblowers (3) below first and second two catalyst layers at least; Be provided with ammonia injector (4) on the cross section of flue gas inlet tube (5).