Tobacco soot cleaning agent for biomass-fired steam boiler as well as preparation method and use method of smoke soot cleaning agent

Abstract

The invention relates to a smoke scale cleaning agent for a biomass-fired steam boiler and a preparation method and a use method of the smoke scale cleaning agent, in particular to the smoke scale cleaning agent for the biomass-fired steam boiler and the preparation method and the use method of the smoke scale cleaning agent. The invention aims to solve the problem that an existing cleaning agent cannot synchronously remove high-carbon residues, alkali metal salts and silicon-calcium composite scales. The cleaning agent is prepared from 15-25 parts of sulfamic acid, 10-20 parts of phosphoric acid, 20-30 parts of a composite alkaline descaling agent, 5-10 parts of citric acid and 600 parts of water. The method comprises the following steps: dissolving sulfamic acid, phosphoric acid and citric acid in water, and stirring until the materials are completely dissolved; adding a composite alkaline descaling agent component, and stirring to react for 2 hours at the constant temperature of 60 DEG C; and cooling to room temperature, and standing and curing for 4 hours for use. Aiming at the characteristics of high carbon and multiple minerals of the sugarcane soot, the invention solves the problem of low efficiency of the existing single agent. The invention is applied to the field of boiler soot cleaning agents.

Description

Technical Field

[0001] This invention relates to a cleaning agent for soot from biomass-fired steam boilers, its preparation method, and its application method. Background Technology

[0002] The soot produced by biomass (such as sugarcane) combustion contains a high proportion of carbonaceous residues (incomplete combustion products such as cellulose) and inorganic minerals such as potassium, sodium, silicon, and calcium. Its composition is significantly more complex than that of coal-fired or oil-fired boilers. This type of soot has a combination of strong adhesion (carbonaceous), acid and alkali resistance (silicates), and easily soluble salts (potassium and sodium), making it difficult to completely remove with conventional single acid or alkaline cleaning agents.

[0003] Existing cleaning agents containing quaternary ammonium salts and sodium silicate are mainly designed for silicate soot from coal-fired / oil-fired boilers. However, the high carbon content in sugarcane soot leads to insufficient penetration of the agents, and the problem of secondary deposition of potassium and sodium salts remains unresolved. While phosphoric acid can dissolve metal oxides and form an anti-corrosion film, it is ineffective against carbon residues. Compound alkaline descaling agents (such as sodium hydroxide + sodium carbonate) can saponify carbon scale but cannot dissolve silica-calcium salts. Therefore, there is an urgent need for a cleaning agent that can simultaneously remove high-carbon residues, alkali metal salts, and silica-calcium complex scale, while also ensuring equipment corrosion resistance. Summary of the Invention

[0004] The purpose of this invention is to solve the problem that existing cleaning agents cannot simultaneously remove high-carbon residues, alkali metal salts, and silicon-calcium complex scale, and to provide a biomass-fired steam boiler scale cleaning agent, its preparation method, and its application method.

[0005] The present invention discloses a biomass-fired steam boiler soot cleaning agent, which is composed of 15-25 parts aminosulfonic acid, 10-20 parts phosphoric acid, 20-30 parts compound alkaline descaling agent, 5-10 parts citric acid and 600 parts water by weight.

[0006] A method for preparing a biomass-fired steam boiler soot cleaning agent is as follows: 1. Weigh 15-25 parts of aminosulfonic acid, 10-20 parts of phosphoric acid, 20-30 parts of compound alkaline descaling agent, 5-10 parts of citric acid and 600 parts of water according to the following mass proportions.

[0007] 2. Dissolve aminosulfonic acid, phosphoric acid and citric acid in water, then add the compound alkaline descaling agent, stir at a constant temperature, cool and let stand to mature, and the process is complete.

[0008] The method of using the biomass-fired steam boiler soot cleaning agent is as follows: spray the cleaning agent onto the soot surface, let it stand and penetrate for 30 minutes, and then activate it with steam for 20 minutes.

[0009] The beneficial effects of this invention are:

[0010] This invention first uses an acidic phase (sulfamic acid + phosphoric acid) to dissolve metal oxides and potassium and sodium salts; then, an alkaline phase (sodium hydroxide + sodium carbonate) is used to saponify carbon residues, and surfactants enhance penetration; finally, citric acid is used to inhibit calcium salt redeposition. Furthermore, the passivation film of phosphoric acid and the weak corrosiveness of sulfamic acid reduce equipment damage. This invention addresses the problem of low efficiency of existing single-agent solutions, specifically targeting the high carbon and multi-mineral characteristics of sugarcane soot. Attached Figure Description

[0011] Figure 1 The image shown is of the biomass-fired steam boiler in Example 1 before cleaning.

[0012] Figure 2 The image shows the biomass-fired steam boiler in Example 1 after cleaning. Detailed Implementation

[0013] The technical solution of the present invention is not limited to the specific embodiments listed below, but also includes any combination of the specific embodiments.

[0014] Specific Implementation Method 1: This implementation method is a biomass-fired steam boiler soot cleaning agent composed of 15-25 parts aminosulfonic acid, 10-20 parts phosphoric acid, 20-30 parts compound alkaline descaling agent, 5-10 parts citric acid and 600 parts water by weight.

[0015] Specific Implementation Method Two: This implementation method is the same as Specific Implementation Method One in that the compound alkaline descaling agent is composed of 10-15 parts sodium hydroxide, 5-10 parts sodium carbonate, and 3-5 parts nonionic surfactant by weight. Everything else is the same as in Specific Implementation Method One.

[0016] Specific Implementation Method Three: This implementation method differs from Specific Implementation Method One or Two in that the cleaning agent is composed of 22 parts by weight of aminosulfonic acid, 15 parts by weight of phosphoric acid, 28 parts by weight of compound alkaline descaling agent, 8 parts by weight of citric acid, and 600 parts by weight of water. Everything else is the same as in Specific Implementation Method One or Two.

[0017] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that the composite alkaline descaling agent is composed of 13 parts sodium hydroxide, 10 parts sodium carbonate, and 5 parts nonionic surfactant by weight. Everything else is the same as in Specific Implementation Methods One to Three.

[0018] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods One to Four in that the nonionic surfactant is a fatty alcohol polyoxyethylene ether. Everything else is the same as in Specific Implementation Methods One to Four.

[0019] The fatty alcohol polyoxyethylene ether has an HLB value of 12-14 and a permeation time of ≤10 minutes (measured according to GB / T 5549 standard).

[0020] Specific Implementation Method Six: The preparation method of a biomass-fired steam boiler soot cleaning agent in this implementation method is as follows: 1. Weigh 15-25 parts of aminosulfonic acid, 10-20 parts of phosphoric acid, 20-30 parts of compound alkaline descaling agent, 5-10 parts of citric acid and 600 parts of water according to the following mass proportions.

[0021] 2. Dissolve aminosulfonic acid, phosphoric acid and citric acid in water, then add the compound alkaline descaling agent, stir at a constant temperature, cool and let stand to mature, and the process is complete.

[0022] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Method Six in that the temperature for constant temperature stirring in step two is 60°C. Everything else is the same as in Specific Implementation Method Six.

[0023] Specific Implementation Method Eight: This implementation method differs from Specific Implementation Method Six or Seven in that: in step two, the plant is left to stand and mature for 4 hours. Everything else is the same as in Specific Implementation Method Six or Seven.

[0024] Specific Implementation Method Nine: The method of using a biomass-fired steam boiler soot cleaning agent in this implementation method is as follows: spray the cleaning agent onto the soot surface, let it stand and penetrate for 30 minutes, and then activate it with steam for 20 minutes.

[0025] Specific Implementation Method Ten: This implementation method differs from Specific Implementation Method Nine in that the mass ratio of cleaning agent to soot is 1:(1-15). Everything else is the same as in Specific Implementation Method Nine.

[0026] The beneficial effects of the present invention are verified using the following embodiments:

[0027] Example 1: The biomass-fired steam boiler soot cleaning agent in this example consists of 22 parts by weight of aminosulfonic acid, 15 parts by weight of phosphoric acid, 28 parts by weight of compound alkaline descaling agent, 8 parts by weight of citric acid, and 600 parts by weight of water. The compound alkaline descaling agent consists of 13 parts by weight of sodium hydroxide, 10 parts by weight of sodium carbonate, and 5 parts by weight of nonionic surfactant.

[0028] The preparation method is as follows: Add aminosulfonic acid, phosphoric acid, compound alkaline descaling agent, citric acid and water in the above proportions. Then dissolve aminosulfonic acid, phosphoric acid and citric acid in water, add compound alkaline descaling agent, stir and react at 60°C for 2 hours, cool the raw materials and let stand for 4 hours to mature, and the process is complete.

[0029] Comparative Example 1: The cleaning agent consisted of 20 parts by weight of quaternary ammonium salt, 10 parts by weight of sodium silicate and 600 parts by weight of water.

[0030] Comparative Example 2: A single phosphoric acid solution (20%) with a mass concentration of phosphate.

[0031] Comparative Example 3: The cleaning agent consisted of 20 parts by weight of aminosulfonic acid, 15 parts by weight of phosphoric acid and 600 parts by weight of water.

[0032] The cleaning effect was tested using the cleaning agents from the examples and comparative examples. The cleaning agents were sprayed onto the surface of the soot, allowed to stand and penetrate for 30 minutes, and then activated with steam at 60°C for 20 minutes. The cleaning results are shown in Table 1.

[0033] Soot sample: taken from the convection tube of a sugarcane boiler in a sugar factory. The composition was confirmed by Agilent 630 infrared spectroscopy: carbon 35%, K2O 15%, SiO2 20%, CaO 10%. 304 stainless steel test piece (50×50×2mm) with a 2mm thick soot coating on the surface.

[0034] Table 1

[0035] Group Carbon residue rate Potassium and sodium removal rate Silicon and calcium removal rate <![CDATA[Metal corrosion rate (g / m 2 ·h)]]> Example ≤5％ ≥98％ ≥90％ ≤0.2 Comparative Example 1 28％ 85％ 40％ 0.5 Comparative Example 2 32％ 92％ 65％ 0.3 Comparative Example 3 31％ 88％ 57％ 0.5

[0036] Experimental results show that the present invention significantly improves the removal rate of composite soot through component synergy, and the corrosion rate is lower than the industry standard (0.5 g / m³). 2 ·h).

[0037] The cleaning agent used in this example was used to clean a sugarcane bagasse-fired boiler at a sugar factory. Before and after images are shown below. Figure 1 and 2 As shown, this demonstrates the thorough removal effect of the cleaning agent on sticky carbon deposits.

Claims

1. A biomass-fired steam boiler soot cleaning agent, characterized in that... The cleaning agent is composed of 15-25 parts aminosulfonic acid, 10-20 parts phosphoric acid, 20-30 parts compound alkaline descaling agent, 5-10 parts citric acid and 600 parts water by weight.

2. The biomass-fired steam boiler soot cleaning agent according to claim 1, characterized in that... The compound alkaline descaling agent is composed of 10-15 parts sodium hydroxide, 5-10 parts sodium carbonate and 3-5 parts nonionic surfactant by weight.

3. The biomass-fired steam boiler soot cleaning agent according to claim 1, characterized in that, The cleaning agent is composed of 22 parts aminosulfonic acid, 15 parts phosphoric acid, 28 parts compound alkaline descaling agent, 8 parts citric acid and 600 parts water by weight.

4. The biomass-fired steam boiler soot cleaning agent according to claim 3, characterized in that, The composite alkaline descaling agent is composed of 13 parts sodium hydroxide, 10 parts sodium carbonate and 5 parts nonionic surfactant by weight.

5. The biomass-fired steam boiler soot cleaning agent according to claim 1, characterized in that, The nonionic surfactant is a fatty alcohol polyoxyethylene ether.

6. The preparation method of a biomass-fired steam boiler soot cleaning agent as described in claim 1, characterized in that... The preparation method is as follows:

1. Weigh 15-25 parts of aminosulfonic acid, 10-20 parts of phosphoric acid, 20-30 parts of compound alkaline descaling agent, 5-10 parts of citric acid and 600 parts of water according to the following mass proportions; 2. Dissolve aminosulfonic acid, phosphoric acid and citric acid in water, then add the compound alkaline descaling agent, stir at a constant temperature, cool and let stand to mature, and the process is complete.

7. The method for preparing a biomass-fired steam boiler soot cleaning agent according to claim 6, characterized in that, The temperature for constant temperature stirring in step two is 60℃.

8. The method for preparing a biomass-fired steam boiler soot cleaning agent according to claim 6, characterized in that, In step two, let it stand and mature for 4 hours.

9. The method of using a biomass-fired steam boiler soot cleaning agent as described in claim 1, characterized in that, The method of use is as follows: spray the cleaning agent onto the surface of the soot, let it stand and penetrate for 30 minutes, and then activate it with steam for 20 minutes.

10. The method of using a biomass-fired steam boiler soot cleaning agent according to claim 9, characterized in that... The mass ratio of cleaning agent to soot is 1:(1-15).

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