SU1237243A1 - Method of cleaning gases from nitrogen oxides - Google Patents

Description

The invention relates to methods for sanitizing ventilation emissions containing nitrogen oxides, and can be applied in the chemical and other industries.

The purpose of the invention is to reduce the consumption of urea.

Example. At the pilot plant, a solution containing 5-10% urea solution and up to 0.3-0.5% sulfamic acid heated to 75-80 ° C was used as an absorbent with the following process parameters:

Performance

gas m / h 900 Concentration

 N0 at the inlet, g / m 0.5-5.4 Hydraulic resistance of the absorber, kgf 1.4 Gas velocity in the cross section of the packed layer, m / s 3.0 Density 1

irrigation, l / m 0.35 Temperature of gas entering. For purification, C 20-34

five

0

five

An electrically heated container was used to heat the absorbent, while simultaneously using a mixture to prepare the working solution.

Urea and sulfamic acid are introduced into the water in dry form in calculated portions.

The working solution for irrigation was supplied from the electrically heated tank by the pump according to the scheme: tank — inertial filter absorber — tank.

At the same time, nitrogen oxides were reduced to nitrogen; Sulfamic acid was also involved in the reduction with the formation of nitrogen and sulfuric acid, which prevents the formation of explosive nitrates.

The degree of reduction of nitrogen oxides with an aqueous solution of a mixture of urea and sulfamic acid, depending on the temperature, is presented in the table.

The consumption of urea at 99.8% degree of purification from NOy was 0.82 tons, and sulfamic acid was 0.03 tons per I t of neutralized NOy.

The concentration of nitrogen oxides, g / m

at the entrance to the absorber

2.26 3.16 5.06

at the outlet of the absorber

0.014 0.035 0.010

Compiler G.Vinokurova Editor L.Pchelinska Tehred L.Oleinik Proofreader T.Kolb

3222/8

Circulation 663 Subscription

VNIIPI USSR State Committee

for inventions and discoveries N3035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, Projecto st., 4

1237243

Table continuation

The degree of reduction of nitrogen oxides.

Initial degree of oxidation is N0,

99.4 98.9 99.8

76 76 78

Claims (2)

1. METHOD FOR CLEANING GASES FROM NITROGEN OXIDES by treating with a heated aqueous solution of urea with sulfuric acid; 2. The method according to π, 1, o tl and h is thin with the fact that they use urea and sulfamic acid concentrations of 5-10 and 0.3-0.5 wt.%, Respectively, at a solution temperature of 75-80 ^{< ?} WITH. £ (L with: to with <1 to with > 1237243