SU1611419A1 - Method of cleaning waste gases form nitrogen oxides - Google Patents

Abstract

The invention relates to a technology for purifying waste gases from nitrogen oxides, used in heat and power engineering, in the metallurgical and chemical industries, and making it possible to reduce the temperature of the process and reduce the cost of it. Exhaust gases with nitrogen oxide impurities are passed through carbon-containing material, which is a waste from the process of incomplete low-temperature burning of brown coal. The waste contains 80.01-81.31 wt.% Carbon. At 350-450 ° C, almost complete purification from nitrogen oxides is achieved, the impurities of carbon monoxide are not higher than the MPC. 3 tab.

Description

The invention relates to the purification of waste gases from harmful emissions of nitrogen oxides and can be used in heat and power engineering, the chemical and petrochemical industry, ferrous and nonferrous metallurgy.

The purpose of the invention is to reduce the temperature of the process and reduce its cost. An example. The waste composition of the incomplete low temperature process, for example, the vortex burning of brown coal (mechanical burn) is given in Table 1.

Through a layer of burned-out height / J mm, the products of combustion of natural gas are passed at. containing

 ; D /. The concentration of W, before and after the layer, is measured. The contact time of the gases with the layer is C. At the outlet of the layer, the NO content is 0.167 g / nm CO 0.04% by volume.

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As a result of the interaction of nitrogen oxides with carbon annealed, carbon material is heated and nitrogen oxides are reduced to nitrogen and carbon dioxide at 350-450 ° C

C + 2NO

WITH ,, + s,

J 2 Primera. Products of natural gas combustion at 350 ° C are passed through a 75-mm-high mechano-burned layer, the contact time {CQ holding N0 to the layer is -0.370 g / nm, and after the layer - 0.008 g / nm CO 0.1% by volume. one

.Primerz. Products of natural gas, at 3800 ° C, are passed through a 75-mm-high mechano-burned layer, the contact time ° f, the content of NOx to the compositional layer is 0.372 g / nm, and after the layer has not been found, the sensitivity

05

WITH

1611419

ten

15

The set for measuring N0 is 10–5 vol.%, CO 0.1 RB%. I Table 2 presents data on the dependence of the content of nitrogen oxides after- (when the exhaust gases pass through a layer of mechanical burns, depending on the carbon content in the mechanical burned burner (temperature of the experiment is T 380 C).

 EXAMPLE 4. Combustion products of natural gas are passed through a 75 mm-high mechanized bed at a contact time of 1 s. The HOCx content to the layer is 0.369 g / nm, after layer N0 is not detected. However, an insignificant amount of CO (0.2 vol.%) Was found in the gas after walking through the Layer. I froze. The products of combustion of natural gas at iA80 ° C are passed through a mechanically burned bed with a height of 75 mm. Content N0) to layer; 0.370 g / nm contact time (,. 1 s, CO is not detected. After a layer of CO 25

 0.5% by volume

The dependence of the efficiency of cleaning-. Tables of combustion products of natural gas and the amount of carbon monoxide generated from the temperature of their passage through the incineration layer are given in Table 3.

20

 ,

0

15

25

20

As can be seen from Table 3, at a temperature of 350-4500s, almost 100% of the degree of purification of flue gases from III is achieved (which is 150-300 ° C lower than in the known method. At 350 ° C, the CO concentration is 0, 1%, at 450 C - 0.2%, which is below the maximum permissible concentration, and at 480 ° C - 0.5%, which is equal to the minimum permissible concentration of CO emitted into the atmosphere.

Since the fire burner is a waste of the coal combustion process, using it in flue gas cleaning systems for nitrogen oxides will reduce the cost of the process and, in addition, will reduce environmental pollution by waste of thermal power plants, the invention claims

The method of purifying waste gases from nitrogen oxides by contacting with carbonaceous material at elevated temperature, characterized in that, in order to reduce the process temperature and its reduction, the waste of the process of incomplete low-temperature combustion is used as carbon-containing material. brown coal containing 80.01-31.31 wt.% carbon.

Table 1

Content, wt.% In the composition of the components of the hydrogen Hydrogen Nitrogen Sulfur | Ash I Moisture

80.01 0.75 0.170.95 10.9 Else 81.31 0.79 0.23 0.11 12.1 - T a b

--- Conditions of - Content N0, g / nm, with the content, measure C in mechano-burn,%

80.01 I 80.1 G80.77 | 81.2 j 81.31

Before a layer of 0.370 0.369 0.372 0.371 0.369 After a layer of 0.015 0.002 About 0.004 0.023

0.371 0.370 0.372 0.369 0.370

ABOUT

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Claims (1)

2Q Claims The method of purification of exhaust gases from nitrogen oxides by contacting with a carbon-containing material at an elevated temperature, characterized in that, in order to reduce the process temperature and reduce its cost, a waste of the incomplete low-temperature combustion of brown coal containing 80.01-81 is used as a carbon-containing material May 31.% carbon. Table! Content, ι 14s1C "% as a part of components Carbon | hydrogen | Nitrogen | Sulfur | Ash | Moisture 80.01 81.31 0.75 0.79 0.17 0.23 0.95 0.11 10.9 12.1 Rest - ” __________ _ Table 2 Measurement conditions 3 The content of Ν0 _χ , g / nm, C in the mechanical burn, when content,% 80.03 | zo, 1 | 80.77 81.2 | 81.31 Before layer After layer 0.370 0.015 0.369 0.002 0.372  0 0.371 0.004 0.369 0,023 5 1611419 6 t a b l and a 3 t, ° s Content s Ν 0 _χ , g / nm Content CO, g / nm ³ Before layer | After layer Before layer 1 After layer 330 0.371 0.167 0 0.04 350 0.370 0.008 0 0.1 380 0.372 0 0 0.1. 450 0.369 0 0 0.2 480 0.370 0 0 0.5