CN111215046A

CN111215046A - Flue gas denitration catalyst

Info

Publication number: CN111215046A
Application number: CN201811413889.0A
Authority: CN
Inventors: 黄辉
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-11-26
Filing date: 2018-11-26
Publication date: 2020-06-02

Abstract

The invention provides a flue gas denitration catalyst, which is used for flue gas denitration and nitrogen oxide removal in the fields of thermal power plants, coal-fired power plants, gas turbine units, waste incineration, steel, petrifaction, internal combustion engine units and the like. The TiO2 is used as a carrier, V2O5 and WO3 are added to the carrier for calendaring and forming, and the porous structure inlet corner part reinforcement and the glass integral fiber reinforcement are adopted, so that the low-temperature denitration efficiency can be improved, the light weight is convenient for construction, the poisoning resistance is improved, the thermal shock resistance is enhanced, and the service life of the catalyst is prolonged. The installation method comprises the following steps: and (5) mounting operation in non-rainy days.

Description

Flue gas denitration catalyst

Technical Field

The invention relates to the technical field of catalysts, in particular to a flue gas denitration and denitrogenation oxide catalyst in the fields of thermal power plants, coal-fired power plants, gas turbine units, waste incineration, steel, petrifaction, internal combustion engine units and the like.

Background

At present, the state has come out of strict control indexes of nitrogen oxides, and the electric power group enters the intensive denitration period. Enterprises adopt a Selective Catalytic Reduction (SCR) method to denitrate smoke, and two catalysts are selected, one is honeycomb type, and the other is plate type. However, some pollutants in the complex flue gas easily cause the catalyst to be poisoned and invalid, the activity of the dust particles is reduced after covering the surface of the catalyst, and meanwhile, SO2 in the flue gas reacts with unreacted HN3 in the flue gas to generate NH4HSO4 and (NH4)2SO4, SO that the corrosion and the blockage of equipment are caused, the catalyst is regenerated early, and the cost is increased.

Disclosure of Invention

The invention aims to overcome the defects of the prior art that pollutants cause catalyst poisoning failure, dust particles cause catalyst activity reduction, and equipment is easy to corrode and block. The invention reduces smoke blockage, prevents catalyst poisoning, enhances abrasion resistance, improves equipment denitration efficiency, prolongs the service life of the catalyst and reduces enterprise cost.

The technical scheme adopted by the invention for solving the technical problems is as follows: the invention has short manufacturing time (usually 2-3 days), adopts TiO2 as a carrier, adds V2O5 and WO3 to carry out calendaring molding, improves the low-temperature denitration efficiency, adopts a porous structure, is light in weight, is convenient for construction, improves the anti-poisoning performance, strengthens the corner part of an inlet, strengthens the integral glass fiber, and enhances the thermal shock resistance.

Poisoning: if the alkali metal ions (Na +, K +, etc.) from the fly ash directly contact with the catalyst, the alkali metal ions adsorbed on the active sites of the catalyst occupy the acid sites on the surface of the catalyst and adhere to the catalyst in the form of soluble substances to react with the active substances in the catalyst, thereby reducing the activity of the catalyst and poisoning the catalyst with the alkali metal. As poisoning is caused by that gaseous As2O3 in flue gas diffuses into the inner pore channels of the catalyst and is subjected to capillary condensation in the capillary pores of the catalyst or reacts with active sites of the catalyst to cause the activity of the catalyst to be reduced. The invention adopts a method for controlling the distribution of catalyst pores to ensure that the inner pores of the catalyst are uniformly distributed so as to control the distribution quantity of capillary pores to reduce capillary condensation. In addition, MoO3 was added to the catalyst to react MoO3 with gaseous As2O3 to reduce As poisoning. Meanwhile, the material has the performances of resisting SO2, halogen (HC, 1HF), alkali metal (Na2O, K2O), heavy metal (As) and the like.

And (3) sintering: the crystal form of TiO2 in the catalyst is changed due to CaO in the dust, so that the particles are enlarged, the surface area is reduced, and the activity is reduced; CaO and SO3 generate CaSO4, the surface volume of the CaSO4 is increased, the CaSO4 expands, the CaSO and the SO are bonded with each other to form a bridge, the surface of the catalyst is shielded, and the catalyst can be sintered when exposed to a high-temperature environment of more than 450 ℃ for a long time. The regeneration rate of the catalyst after sintering is almost zero. The addition of WO3 according to the invention minimizes sintering of the catalyst. Under the condition of using high-sulfur coal, the catalyst should be large in pore size, wall thickness and sectional area, the pressure drop is small when smoke passes through, dust particles can smoothly pass through, deposition is not easy to generate, and CaSO4 is generated.

Corrosion resistance: the invention adopts ceramic fiber as a carrier, the corner part of the inlet is reinforced, the integral glass fiber is used for reinforcing the edge of the top end of the catalyst, the hardness and toughness of the edge of the catalyst are improved, the mechanical stability is good, the erosion abrasion is resistant, and the base material and the carrier have stronger mechanical abrasion resistance and thermal shock resistance.

And (3) designing the aperture: the range of the number of holes of the present invention: 15 to 88/cell; pore diameter: 5.2mm-20 mm; the hole height is as follows: 3mm-9 mm; thickness: 0.4mm-1mm, so that the denitration catalyst has low resistance (operation cost is saved), and the micropore distribution is proper, so that the stable denitration performance is achieved, and the catalyst poisoning can be effectively avoided.

Compared with the prior art, the invention has the advantages and beneficial effects that: the most appropriate micropore volume is adopted, so that the denitration performance and the wear-resisting strength reach the optimal balance point; the most suitable micropore distribution is designed to achieve stable denitration performance; the most appropriate active ingredients are adopted, SO that the denitration rate is ensured, and the conversion rate of SO2/SO3 is effectively inhibited; by adding the third component, the increase of the conversion rate of SO2/SO3 in the running process is effectively inhibited; the activity of the product is uniform, and even if the surface is abraded, the activity of the rest part is not changed; the resistance is low, and the operation cost is saved; low temperature and high activity, and high NOx removal rate; high water resistance;

high temperature corrosion resistance; high mechanical strength and heat resistance; long service life, low running cost and great economic and social benefits.

Detailed Description

The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art.

Example 1

The catalyst module is installed in rainy days, the storage place is also considered well, and the installation operation is stopped in rainy days. During installation, an operation method is adopted to avoid damage to the catalyst caused by factors such as tools, metal fragments, electric welding sparks and the like, and supervision and management are thoroughly enhanced. Fixing a carrying Jig tool (Lifting Jig) on a carrying Hole (Lifting Hole) on the catalyst, hoisting the Lifting Jig tool (Lifting Jig) fixed on the Lifting Hole into the reactor from an above-ground crane, hoisting the fixed Lifting Jig tool (Lifting Jig) by the crane to the inside of the reactor too fast, carefully avoiding collision with other modules, and forbidding urgent acceleration or urgent stop by using a stable route as far as possible. The catalyst module moves towards the inside of the reactor and is distributed and installed by using a balance rail, and the catalyst module always moves in a horizontal state.

It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. The utility model provides a flue gas denitration catalyst, is used for flue gas denitration nitrogen oxide removal catalysts such as steam power plant, coal-fired power plant, gas turbine unit, msw incineration, steel, petrochemical industry, internal-combustion engine group, and the manufacturing time is short, has added V2O5 and WO3 calendering molding in using TiO2 as the carrier, adopts porous structure, and the enhancement of entrance corner portion and the whole fiber reinforcement of glass, characterized by: the low-temperature denitration efficiency is improved, the light weight is convenient for construction, the poisoning resistance is improved, and the thermal shock resistance is enhanced.

2. The catalyst of claim 1, wherein: the number of holes is 15 to 88 per unit; the aperture is 5.2mm-20 mm; the height of the hole is 3mm-9 mm; the thickness is 0.4mm-1mm, and the micropore distribution is suitable, so that the stable denitration performance is achieved, the catalyst poisoning can be effectively avoided, the low-resistance characteristic is achieved, and the operation cost is saved.

3. The metallic paint according to claim 1, wherein: the most appropriate active ingredients are adopted, SO that the denitration rate is ensured, and the increase of the conversion rate of SO2/SO3 in the operation process is effectively inhibited; the activity of the product is uniform, and even if the surface is abraded, the activity of the rest part is not changed; the NOx removal rate is high; high water resistance.