阅读说明：本技术 一种干式trt机组专用的氯化铵阻垢剂及其制备方法 (Ammonium chloride scale inhibitor special for dry TRT unit and preparation method thereof ) 是由 张蓉 曹惠政 王海博 于 2021-08-06 设计创作，主要内容包括：本发明公开了一种干式TRT机组专用的氯化铵阻垢剂及其制备方法与应用,该氯化铵阻垢剂由以下质量百分比的原料组成：醇胺类有机物30-45％,酸性气体脱除剂10-30％,水溶性极性溶剂10-15％,其余量为水,以上组分质量百分比之和为100％；其中醇胺类有机物为单异丙醇胺。本发明制备的氯化铵阻垢剂仅能够直接与氯化铵反应除垢,且该氯化铵阻垢剂具有小分子易汽化、稳定性好等特点,显著的解决了目前高炉煤气出口温度降低工况下传统药剂分子量大,难以汽化,粘连在动叶片,导致机组主轴振动值增大、缩短机组的运行周期的问题。(The invention discloses an ammonium chloride scale inhibitor special for a dry TRT unit, and a preparation method and application thereof, wherein the ammonium chloride scale inhibitor is prepared from the following raw materials in percentage by mass: 30-45% of alcohol amine organic matter, 10-30% of acid gas remover, 10-15% of water-soluble polar solvent and the balance of water, wherein the sum of the mass percentages of the components is 100%; wherein the alcamines organic matter is monoisopropanolamine. The ammonium chloride scale inhibitor prepared by the invention can only directly react with ammonium chloride to remove scale, has the characteristics of easiness in vaporization of small molecules, good stability and the like, and remarkably solves the problems that the traditional medicament has large molecular weight, is difficult to vaporize and is adhered to moving blades under the working condition of reducing the temperature of the gas outlet of the blast furnace at present, so that the vibration value of a main shaft of a unit is increased and the operation period of the unit is shortened.)

1. The special ammonium chloride scale inhibitor for the dry TRT unit is characterized by comprising the following raw materials in percentage by mass:

30-45% of alcohol amine organic matter, 10-30% of acid gas remover, 10-15% of water-soluble polar solvent and the balance of water, wherein the sum of the mass percentages of the components is 100%.

2. The ammonium chloride scale inhibitor special for the dry TRT unit according to claim 1, wherein the alkanolamine organic substance is monoisopropanolamine.

3. The ammonium chloride scale inhibitor special for the dry TRT unit as claimed in claim 1, wherein the acid gas remover is monoethanolamine or diglycolamine or a mixture of monoethanolamine and diglycolamine.

4. The ammonium chloride scale inhibitor special for the dry TRT unit according to claim 1, wherein the water-soluble polar solvent is N, N-dimethylformamide or hexamethylphosphoric triamide or a mixture of the N, N-dimethylformamide and the hexamethylphosphoric triamide.

5. The ammonium chloride scale inhibitor special for the dry TRT unit as claimed in claim 1, wherein the ammonium chloride scale inhibitor is prepared from a mixture of ammonium chloride, ammonium chloride and waterThe concentration of the ammonium chloride scale inhibitor added into blast furnace gas is 80-120 ml/(10)⁴m³)。

6. The preparation method of the ammonium chloride scale inhibitor special for the dry TRT unit according to any one of claims 1 to 5, characterized by comprising the following steps:

s1, adding at least one of N, N-dimethylformamide and hexamethylphosphoric triamide with the mass percentage of 10-15% into the balance of water, and stirring at room temperature until the N, N-dimethylformamide and the hexamethylphosphoric triamide are completely dissolved;

s2, adding 30-45% by mass of monoisopropanolamine into the solution obtained in the step S1, and stirring at room temperature for 20 min;

s3, adding at least one of monoethanolamine and diglycolamine with the mass percentage of 10-30% into the solution obtained in the step S2, and stirring for 30min at constant temperature to fully dissolve the monoethanolamine and diglycolamine to obtain a finished product.

Technical Field

The invention relates to a scale inhibitor, in particular to an ammonium chloride scale inhibitor special for a dry TRT unit and a preparation method thereof.

Background

The blast furnace gas residual pressure turbine power generation device, TRT for short, is mainly used for recovering pressure energy and heat energy of a byproduct (blast furnace gas) generated in the blast furnace smelting process, can recover 30-50% of energy required by a blast furnace blower for power generation, has obvious economic benefit, and is a good energy-saving and environment-friendly device for iron and steel enterprises.

The medium of the TRT unit is dedusted coal gas from the top of the blast furnace, and a certain amount of dust and saturated steam can be remained in the gas phase medium although dry dedusting is adopted. Besides, the coal gas also contains oil mist which can not be completely removed by dust-removing equipment and several acidic gases (for example, H) produced by impure blast furnace raw material₂S、HCl、CO₂Etc.). Therefore, the gas-steam-solid multiphase flow finally enters the TRT unit. After the coal gas enters the TRT unit, the flow rate and the temperature are obviously reduced due to expansion work, and acid gas in the coal gas is dissolved in condensed water to form a layer of micro-thin acid water film on the surface of the blade, so that the surface of the blade is corroded and damaged. The surface smoothness of the corroded metal is reduced sharply, so that corrosion products, oil dirt, dust and the like are easier to attach to the blades, and meanwhile, due to the reduction of the temperature, the flow speed, the pressure and the like of the coal gas, the complexity of the coal gas is as follows: NH (NH)₄ ⁺、Cl^-And the like, and various inorganic compound crystals can be formed by synthesis reaction, and the inorganic compound crystals can be attached to the metal surface, and can adsorb impurities in the coal gas to form charged particles with larger particle size. All the charged micro particles can be attached to parts such as moving blades, static blades, inlet and outlet pipelines of the TRT set to form a scaling phenomenon, and the dynamic balance of the TRT set is damaged due to uneven scaling, so that the generating power of the TRT set is reduced, the vibration value of a main shaft is continuously increased until the TRT set automatically jumps and stops, and the device is frequently overhauled. In order to effectively prolong the overhaul period of the device and improve the power generation power of the device, the scale inhibitor is a mature solution at present.

But with changes in the field conditions, specifically: along with the further improvement of the utilization rate of heat energy in the blast furnace ironmaking link, the temperature of a blast furnace gas outlet (TRT inlet) is obviously reduced, and the mature TRT scale inhibitor in the existing market contains macromolecular organic matters such as imidazoline or organic phosphate. Under the condition that the TRT inlet temperature is remarkably reduced, macromolecular organic matters enter a front-end gas pipeline, work is done along with gas expansion, after the temperature of blast furnace gas is further reduced, the macromolecular organic matters are difficult to vaporize, the temperature is reduced, and the flowability is also poor, so that the macromolecular organic matters are easily adhered to TRT moving blades, and the vibration value of a main shaft of a unit is increased continuously, and the operation period of the unit is shortened. In order to ensure the stable operation of the TRT unit on site, avoid blast furnace damping down caused by TRT unit failure and increase the operation cost of iron and steel enterprises, the development of a scale inhibitor suitable for the working condition that the temperature of a blast furnace gas outlet is obviously reduced is urgently needed.

In view of the above, the inventor provides an ammonium chloride scale inhibitor special for a dry TRT unit and a preparation method thereof through a plurality of research and development tests by virtue of experience and practice of related industries for many years, so as to overcome the defects in the prior art.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides an ammonium chloride scale inhibitor special for a dry TRT unit and a preparation method thereof.

The purpose of the invention is realized by the following technical scheme:

an ammonium chloride scale inhibitor special for a dry TRT unit comprises the following raw materials in percentage by mass:

30-45% of alcohol amine organic matter, 10-30% of acid gas remover, 10-15% of water-soluble polar solvent and the balance of water, wherein the sum of the mass percentages of the components is 100%.

Further, the alkanolamine organic substance is monoisopropanolamine.

Further, the acid gas remover is monoethanolamine or diglycolamine or a mixture of monoethanolamine and diglycolamine.

Further, the water-soluble polar solvent is N, N-dimethylformamide or hexamethylphosphoric triamide or a mixture of the two.

Furthermore, the concentration of the ammonium chloride scale inhibitor added into the blast furnace gas is 80-120 ml/(10)⁴m³)。

A preparation method of an ammonium chloride scale inhibitor special for a dry TRT unit comprises the following steps:

s1, adding at least one of N, N-dimethylformamide and hexamethylphosphoric triamide with the mass percentage of 10-15% into the balance of water, and stirring at room temperature until the N, N-dimethylformamide and the hexamethylphosphoric triamide are completely dissolved;

s2, adding 30-45% by mass of monoisopropanolamine into the solution obtained in the step S1, and stirring at room temperature for 20 min;

s3, adding at least one of monoethanol amine and diglycolamine with the mass percent of 10-30% into the solution obtained in the step S2, and stirring at constant temperature for 30min to fully dissolve the mixture to obtain the finished product.

Compared with the prior art, the technical scheme provided by the invention has the following beneficial effects:

the ammonium chloride scale inhibitor prepared by the invention is in a liquid state, the dosage of the ammonium chloride scale inhibitor is related to the scaling degree of a TRT unit, and the general use concentration is 80-120 ml/(10)⁴m³) The adding method is characterized in that a metering pump is used for injecting the ammonium chloride scale inhibitor into a gas pipeline in a vein injection mode, and the ammonium chloride scale inhibitor has the characteristics of easiness in vaporization of small molecules, good stability and the like, is mixed with gas immediately and is vaporized immediately under the action of waste heat of the gas, monoisopropanolamine in the ammonium chloride scale inhibitor is eutectic with inorganic salt crystals in the gas or adsorbed on the surface of crystals, crystal lattices are distorted, and the crystallization behaviors and orientation of the inorganic salts such as ammonium chloride and the like are damaged; the shape and the size of the crystal are changed, the three-dimensional network structure formed by intercrystalline bonding is avoided, the continuous formation and development of the crystal are prevented, and the salt crystal in the coal gas is prevented from being deposited on the blades, the rotors and other parts of the unit; meanwhile, the acid gas remover follows the principle that small molecules are easy to vaporize, so that on one hand, the acid gas remover can better capture and absorb acid gas in blast furnace gas, and has a certain corrosion inhibition effect on the whole TRT unit due to acid gas corrosion; on the other hand, the presence of an acid gas-removing agent isThe contact interface of monoisopropanolamine and ammonium chloride is maintained to be still in an alkaline environment, and scale inhibition is facilitated in the alkaline environment; the water-soluble polar solvent ensures that monoisopropanolamine reacts with ammonium chloride, and the acidic gas remover and the acidic gas in the coal gas generate organic matters which are then instantly dissolved in the polar organic solvent, so that the phenomenon that the vibration value of a main shaft of a unit is increased due to the adhesion of byproducts to moving blades is avoided. After the ammonium chloride scale inhibitor is adopted, the operation period of the TRT unit can be obviously prolonged, and the income of enterprises is obviously improved.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described below by specific examples. It is to be understood that such description is merely illustrative and not restrictive of the scope of the invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.

The invention provides an ammonium chloride scale inhibitor special for a dry TRT unit, which comprises the following raw materials in percentage by mass: 30-45% of alcohol amine organic matter, 10-30% of acid gas remover, 10-15% of water-soluble polar solvent and the balance of water, wherein the sum of the mass percentages of the components is 100%.

The alkanolamine organic matter used in the invention is monoisopropanolamine, which cannot be vaporized in a low-temperature environment compared with a bisimizoline macromolecular structure, and particularly, in TRT, the gas temperature is in a descending trend, so that a macromolecular system is not suitable for use. The monoisopropanolamine is used for achieving the effect of vaporization by utilizing the small molecular weight, and then the traditional monoisopropanolamine is used for a scouring agent, an antistatic agent, a dyeing assistant and a fiber wetting agent, and under the working condition of ammonium chloride, the monoisopropanolamine can directly react with the ammonium chloride to achieve the effects of scale inhibition and scale removal.

The acid gas remover is at least one of monoethanolamine and diglycolamine, and also follows the principle that small molecules are easy to vaporize, so that the scale inhibitor can better capture and absorb acid gas in blast furnace gas, and has a certain corrosion inhibition effect on the whole TRT unit due to corrosion of the acid gas.

The water-soluble polar solvent is at least one of N, N-dimethylformamide and hexamethylphosphoric triamide, and the use of the water-soluble polar solvent can ensure that the acidic gas remover and the acidic gas in the coal gas generate organic matters and then are instantly dissolved in the polar organic solvent, so that the phenomenon that the vibration value of a main shaft of a unit is increased due to the adhesion of byproducts to moving blades is avoided.

The concentration of the ammonium chloride scale inhibitor added into blast furnace gas is 80-120 ml/(10)⁴ m³)。

In conclusion, the invention utilizes the reaction of monoisopropanolamine and ammonium chloride to destroy the crystallization behavior and orientation of inorganic salts such as ammonium chloride and the like, change the shape and size of crystals, avoid intercrystalline bonding to form a three-dimensional network structure, prevent the continuous formation and development of the crystals, and prevent salt crystals in gas from depositing on the blades, rotors and other parts of a unit; the acidic absorbent provides an alkaline environment to ensure high reaction efficiency of monoisopropanolamine and ammonium chloride, and absorbs acidic gas in a coal gas medium; the water-soluble polar molecules are mainly used for dissolving organic salts and the like generated in the first two reactions, so that secondary scaling on the blades is avoided. Therefore, the three raw materials of the invention are consistent and compatible, and the scale inhibition effect cannot be achieved by only using one of the raw materials alone because: monoisopropanolamine can react with ammonium chloride well under the alkaline environment, so that an acid gas absorbent is needed to absorb acid gas in coal gas to provide the alkaline environment; ② if the monoisopropanolamine, the acidic absorbent, the ammonium chloride and the by-products generated by the acidic gas are not dissolved by the water-soluble polar solvent, the secondary products will stay on the leaves, and the scale inhibition effect can not be achieved.

A preparation method of an ammonium chloride scale inhibitor special for a dry TRT unit comprises the following steps:

s1, adding at least one of N, N-dimethylformamide and hexamethylphosphoric triamide with the mass percentage of 10-15% into the balance of water, and stirring at room temperature until the N, N-dimethylformamide and the hexamethylphosphoric triamide are completely dissolved;

s2, adding 30-45% by mass of monoisopropanolamine into the solution obtained in the step S1, and stirring at room temperature for 20 min;

s3, adding at least one of monoethanol amine and diglycolamine with the mass percent of 10-30% into the solution obtained in the step S2, and stirring at constant temperature for 30min to fully dissolve the mixture to obtain the finished product.

The present invention will be described in detail with reference to specific examples, but the present invention is not limited thereto, and the following examples are all prepared by the above-mentioned preparation method.

Example 1

The embodiment provides an ammonium chloride scale inhibitor special for a dry TRT unit, which is prepared from the following raw materials in parts by weight: 45% of monoisopropanolamine, 10% of monoethanolamine, 15% of N, N-dimethylformamide and the balance of water, wherein the sum of the mass percentages of the components is 100%. Because the temperature of the TRT inlet at the site is reduced from 150 ℃ to 90 ℃, the cover is overhauled and uncovered during the use process of the original medicament at the site to find that a large amount of tar substances are adhered to the moving blades, and the adding concentration of blast furnace gas is 80-120ml/(10 ml)⁴m³) After the ammonium chloride scale inhibitor prepared by the invention is used, the vibration value of the main shaft of the unit is stable in the same period, and the moving blades do not find tar substances after the cover is opened.

Example 2

The embodiment provides an ammonium chloride scale inhibitor special for a dry TRT unit, which is prepared from the following raw materials in parts by weight: 38 percent of monoisopropanolamine, 30 percent of monoethanolamine, 10 percent of hexamethylphosphoric triamide and the balance of water, wherein the sum of the mass percentages of the components is 100 percent. Before the scale inhibitor is not added on site, the unit blades are seriously corroded after the cover is opened, and the adding concentration of the blast furnace gas is 80-120ml/(10 ml)⁴m³) After the ammonium chloride scale inhibitor prepared by the invention is used, the vibration value of the main shaft of the unit is stable in the same period, and the blade is not obviously corroded by acid after the cover is opened.

Example 3:

the embodiment provides an ammonium chloride scale inhibitor special for a dry TRT unit, which is prepared from the following raw materials in parts by weight: 30 percent of monoisopropanolamine, 20 percent of monoethanolamine, 13 percent of hexamethylphosphoric triamide and the balance of water, wherein the sum of the mass percentages of the components is100 percent. Before adding scale inhibitor on site, the main shaft vibration value of the unit is larger, the shutdown maintenance period is 2 weeks, and the adding concentration of blast furnace gas is 80-120 ml/(10)⁴m³) After the ammonium chloride scale inhibitor prepared by the invention is operated for 4 months, the vibration value of the main shaft of the unit is still stable.

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all should be considered as belonging to the protection scope of the invention.