A composite organic denitrifier and preparation method thereof

Abstract

The present invention discloses a composite organic denitrifier and a preparation method thereof, which relates to the technical field of denitrification, and comprises 50% to 90% of an active organic mixture, 2% to 7% of a flame retardant, 1% to 3% of an emulsifier, 0.1% to 1% of a buffer, and 1% to 5% of a synergist. The active organic mixture is used as the main raw material, there is no ammonia, no ammonia escape will be generated, and the denitrification efficiency is high, the applicable temperature range is wide, and it is safe and environmentally friendly.

Description

Technical Field

[0001] The present invention relates to the technical field of denitration, and in particular to a composite organic denitration agent and a preparation method thereof. Background Art

[0002] Nitrogen oxides (NO X ) is one of the three main air pollutants (smoke, sulfur dioxide, and nitrogen oxides), and its harmfulness is more profound and extensive than that of sulfur dioxide. With the development of the economy and the improvement of environmental protection requirements, it is urgent to effectively control the air pollution caused by the flue gas emissions of various boilers and kilns, especially to remove nitrogen oxides in combustion flue gas and prevent environmental pollution, which has been sharply raised as a global issue.

[0003] Existing cement kilns, glass kilns, gas-fired, coal-fired and biomass-fired boiler SNCR denitrification systems generally have low denitrification efficiency and are difficult to achieve NO X ≤50mg / Nm 3 In addition to the problems with ultra-low emission standards, the SCR denitrification system has high operating costs, short catalyst life, and cannot achieve low-load denitrification. Summary of the invention

[0004] The present invention aims at the above-mentioned technical problems, overcomes the shortcomings of the prior art, and provides a composite organic denitrifier, comprising 50% to 90% of an active organic mixture, 2% to 7% of a flame retardant, 1% to 3% of an emulsifier, 0.1% to 1% of a buffer, and 1% to 5% of a synergist.

[0005] The technical solution further defined in the present invention is:

[0006] The above-mentioned composite organic denitrifier, the active organic mixture is prepared by mixing biological liquid fertilizer, NaOH, biochar, and propyl butyrate in a ratio of 5:2:1:2.

[0007] The flame retardant of the composite organic denitrifier mentioned above mainly includes tris(2-chloroethyl) phosphate.

[0008] The aforementioned composite organic denitrifier, the emulsifier mainly includes Tween80.

[0009] In the aforementioned composite organic denitrifier, the buffer mainly comprises sodium citrate.

[0010] The aforementioned composite organic denitrifier, the synergist mainly includes sodium oxalate.

[0011] Another object of the present invention is to provide a method for preparing a composite organic denitrifier, the specific steps comprising:

[0012] S1. Add NaOH to water, stir evenly, then add bio-liquid fertilizer, continue stirring to dissolve, then add biochar and propyl butyrate, continue stirring until completely dissolved, to obtain an active organic mixture;

[0013] S2. Add flame retardant to the prepared active organic mixture and stir evenly;

[0014] S3, add emulsifier and stir evenly;

[0015] S4, add buffer and stir evenly;

[0016] S5. Add the synergist and stir evenly to obtain the composite organic denitrification agent.

[0017] The beneficial effects of the present invention are: it adopts an ammonia-free organic denitrification method, which is green and environmentally friendly, operates without ammonia, and avoids the adverse effects of free ammonia from the source; there is no safety problem of liquid ammonia storage; when the boiler is running at low load, the flue gas can also achieve ultra-low emissions. It has the advantages of high denitrification efficiency and simple installation, low investment and equivalent to SNCR, and lower operating costs than SCR denitrification process, which can meet the NO reduction requirements of the unit under full load. X ≤50mg / Nm 3 Ultra-low emission standards requirements. DETAILED DESCRIPTION

[0018] This embodiment provides a composite organic denitrification agent and a preparation method thereof, the specific steps of which include:

[0019] S1. Add 2 grams of NaOH to 75 grams of water, stir evenly by hand or machine, add 5 grams of liquid biological fertilizer, continue to stir until dissolved, add 1 gram of powdered biochar (200 mesh) and 2 grams of propyl butyrate, continue to stir until completely dissolved, and obtain an active organic mixture;

[0020] S2. Add 2 g of a commercially available flame retardant whose main component is tris(2-chloroethyl)phosphate to the prepared active organic mixture, and stir it evenly by hand or mechanical stirring;

[0021] S3, add 2 grams of commercially available emulsifier whose main ingredient is Tween80, and stir evenly by manual or mechanical stirring;

[0022] S4, add 0.2 g of a commercially available buffer whose main ingredient is sodium citrate, and stir evenly by manual or mechanical stirring;

[0023] S5. Add 3 grams of a commercially available enhancer whose main ingredient is sodium oxalate, and stir evenly by manual or mechanical stirring to obtain a composite organic denitrifier.

[0024] The test was conducted on a 60t / h gas boiler in a steel plant and achieved the expected results. This boiler uses blast furnace gas and coke oven gas as fuel, adopts SNCR denitrification method, and uses 20% concentration ammonia water as denitrification agent. Two spray guns are set on each side of the furnace. The initial NO X The content is less than 50mg / Nm³ for a long time, and the denitrification device is basically in a state of suspension. In order to achieve the expected effect, the fuel ratio of the boiler is adjusted, the proportion of coke oven gas is increased, and the initial NO X The content was adjusted to 80-100 mg / Nm³. The test was conducted in ton barrels. The pump and spray gun used the existing SNCR denitrification device. The specific flue gas parameters are as follows:

[0025] Table 1 Existing parameters of boiler flue gas

[0026] project unit parameter Remark Boiler size 60t / h Furnace type Gas boiler fuel Boiler gas, coke oven gas Smoke volume (maximum) <![CDATA[Nm 3 / h]]> 90000 Furnace smoke temperature ℃ 800-900 <![CDATA[NO X Initial Concentration]]> <![CDATA[mg / m 3 ]]> 80-100 Oxygen content % ≤3

[0027] After the denitrification agent of the present invention is added, the flue gas parameters are as follows:

[0028] Table 2 Flue gas parameters after denitrification

[0029] project unit parameter Remark Furnace smoke temperature ℃ 800-900 <![CDATA[NO X Concentration after purification]]> <![CDATA[mg / m 3 ]]> 30-50 Stable time 30min <![CDATA[NO X Minimum concentration]]> <![CDATA[mg / m 3 ]]> 15-20 Increase the amount of denitrification agent, stabilization time 10min Denitrification agent consumption Kg / h 70-100 Maximum consumption: 150Kg / h Denitrification efficiency % 50-85 Expected Results achieve

[0030] It can be seen from the above table that the denitrification agent of the present invention can achieve a higher denitrification efficiency and the expected effect is obvious. The limit consumption in the table refers to increasing the amount of denitrification agent, NO X Denitrification agent consumption when emission concentration is less than 20mg / Nm³. By adjusting the boiler load, when the furnace temperature is 700-800℃, NO X The emission concentration can also be guaranteed to be stable below 50mg / Nm³.

[0031] Compared with the prior art, the present invention uses an active organic mixture as the main raw material, has no ammonia, and will not produce ammonia escape. It has the characteristics of high denitrification efficiency, wide applicable temperature range, safety and environmental protection.

[0032] In addition to the above embodiments, the present invention may also have other implementation modes. Any technical solution formed by equivalent replacement or equivalent transformation falls within the protection scope required by the present invention.

Claims

1. A composite organic denitrifier, characterized in that: It includes 50% to 90% of active organic mixture, 2% to 7% of flame retardant, 1% to 3% of emulsifier, 0.1% to 1% of buffer, and 1% to 5% of synergist; The active organic mixture is prepared by mixing biological liquid fertilizer, NaOH, biochar, and propyl butyrate in a ratio of 5:2:1:2; The flame retardant mainly includes tris(2-chloroethyl)phosphate; The buffer mainly includes sodium citrate; The synergist mainly includes sodium oxalate.

2. A composite organic denitrifier according to claim 1, characterized in that: The emulsifier mainly includes Tween80.

3. A method for preparing a composite organic denitrifier, characterized in that: Applied to claim 1 or 2, the specific steps include: S1. Add NaOH to water, stir evenly, then add bio-liquid fertilizer, continue stirring to dissolve, then add biochar and propyl butyrate, continue stirring until completely dissolved, to obtain an active organic mixture; S2. Add flame retardant to the prepared active organic mixture and stir evenly; S3, add emulsifier and stir evenly; S4, add buffer and stir evenly; S5. Add the synergist and stir evenly to obtain the composite organic denitrification agent.