CN111718688B - Environment-friendly snow-melting agent and production method thereof - Google Patents
Environment-friendly snow-melting agent and production method thereof Download PDFInfo
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Abstract
The invention relates to an environment-friendly snow-melting agent and a production method thereof. The production method of the environment-friendly snow-melting agent comprises the steps of solid-liquid separation of cyclizing liquid, catalytic oxidation treatment, treatment of potassium hydroxide aqueous solution, evaporation concentration and the like. The liquid environment-friendly snow-melting agent and the solid environment-friendly snow-melting agent completely meet the regulations of GB/T23851-. The method for producing the environment-friendly snow melting agent by using the cyclizing liquid generated in the production process of the epichlorohydrin by the glycerol method has the advantages of simple and convenient process flow, easy operation and control, effective utilization of waste resources, obvious social and economic benefits and environmental friendliness.
Description
[ technical field ] A method for producing a semiconductor device
The invention belongs to the technical field of chemical production waste resource utilization. More particularly, the invention relates to an environment-friendly snow melt agent and a production method thereof.
[ background of the invention ]
The ice accumulation on the road surface in winter is always a great problem troubling the road traffic. Because the road surface is covered with ice and snow, the friction between the tire and the ground is reduced, traffic accidents are easily caused, and road traffic paralysis and even major loss of lives and properties are caused in serious cases. In practice, high-grade snow removal in winter mainly depends on mechanical snow removal and snow-melting agent technology to ensure that traffic is opened quickly after snow. The snow-melting agent is irreplaceable to other methods due to high snow-melting efficiency, good effect, simple operation and good anti-icing and anti-skid effects.
The snow-melting agent is a chemical which can lower the freezing point of water and promote the melting of ice and snow, is mainly used for airport, highway, square, parking lot, railway, city street and the like in winter to melt ice and snow and prevent freezing, and mainly comprises the salts of sodium chloride, calcium chloride, magnesium chloride and the like. The snow melting mechanism of the snow melting agent is as follows: (1) after the snow-melting agent is dissolved in water (snow), the freezing point of the snow-melting agent is below zero, for example, after sodium chloride is dissolved in water, the freezing point is-10 ℃, calcium chloride is-20 ℃, and acetates can reach-30 ℃; (2) the dissolution of the salt needs to absorb heat, and simultaneously, the freezing point of the salt water is reduced, so that ice blocks are difficult to form; (3) when the snow-melting agent is dissolved in water, the ion concentration in water increases to lower the vapor pressure of the liquid phase of water, but the vapor pressure of the solid phase of ice does not change, and the ice melts in a state of reaching the vapor pressure of the solid phase of the ice-water mixture.
Since the 20 th century and the 50 th century, western developed countries begin to use the snow-melting agent, the snow-melting agent becomes a main means for maintaining and removing snow, preventing ice and preventing skid of roads in winter, and the snow-removing and skid-preventing agent plays an extremely important and irreplaceable role in snow-removing and skid-preventing work of various countries in the world.
Snow melting agents currently used are largely of two types: the first is a chloride salt type snow-melting agent, which takes one or more of sodium chloride, calcium chloride, magnesium chloride, potassium chloride and the like (generally called deicing salt) as main components, with or without adding corrosion inhibitors. The snow-melting agent has low freezing point, rich resources, low price and good snow-melting effect, and is widely applied to road snow melting with the application proportion of more than 90 percent. The snow-melting agent has great influence on roads, environment and plants, particularly sodium chloride, and the pure calcium snow-melting agent sold in the market at present contains sodium chloride up to 4 percent. The second kind is non-chlorine salt organic matter, which is non-chlorine salt snow melting agent with calcium acetate, magnesium acetate, potassium acetate or several kinds of special organic matter, such as alcohol, urea, etc. as main component. The snow-melting agent has high freezing point, high price and poor snow-melting effect, is used in special areas such as airport runways or bridges with low temperature of more than-10 ℃ in developed countries, has little influence on roads, environment and plants, and is environment-friendly.
The environmental protection is concerned all over the world, and the invention of the snow-melting agent with good ice-melting effect, environmental protection and low price is very necessary to overcome various defects of the existing snow-melting agent. The present inventors have completed the present invention through a large number of experiments and studies.
[ summary of the invention ]
[ problem to be solved ]
The invention aims to provide an environment-friendly snow-melting agent.
The invention also aims to provide a production method of the environment-friendly snow melt agent.
[ solution ]
The invention is realized by the following technical scheme.
The invention relates to a method for producing an environment-friendly snow melting agent by using cyclizing liquid generated in the production process of epichlorohydrin by a glycerol method.
The production method of the environment-friendly snow-melting agent comprises the following steps:
A. solid-liquid separation
Carrying out solid-liquid separation on the cyclized solution to obtain a clear cyclized solution containing an organic compound;
B. catalytic oxidation treatment
Step A, carrying out catalytic oxidation treatment on the clear cyclized liquid containing the organic compound to obtain a calcium chloride solution containing acetic acid;
C. aqueous potassium hydroxide solution treatment
B, treating the calcium chloride solution containing acetic acid with a potassium hydroxide aqueous solution until the pH value is 6-9 to obtain a calcium chloride solution containing potassium acetate;
D. concentrating by evaporation
And C, evaporating and concentrating the calcium chloride solution containing potassium acetate, adding a corrosion inhibitor into the obtained concentrated solution to obtain a liquid environment-friendly snow-melting agent, or treating the liquid environment-friendly snow-melting agent product by a granulation drying system to obtain a solid environment-friendly snow-melting agent.
According to a preferred embodiment of the present invention, in step A, the cyclizing liquid is CaCl by weight2Calcium chloride of pH 7 to 9 containing 12 to 18% of glycerin, 1.5 to 1.0% of water-insoluble matter, 0.6 to 1.2% of chlorine-containing organic compoundA solution; the chlorine-containing organic compound is glycerol mono-chlorohydrin, dichloropropanol, epichlorohydrin and trichloropropane.
According to another preferred embodiment of the invention, in step a, the solid-liquid separation is carried out using a plate and frame filter press or a microporous filter.
According to another preferred embodiment of the present invention, in the step B, the wet air catalytic oxidation treatment is performed for 0.5 to 1.5 hours by using air under the conditions of a pressure of 0.5 to 2.5MPa and a temperature of 100 to 180 ℃.
According to another preferred embodiment of the invention, in step D, the calcium chloride solution containing potassium acetate is concentrated by evaporation to a calcium chloride content of 33 to 37% by weight.
According to another preferred embodiment of the present invention, in step D, the corrosion inhibitor is one or more corrosion inhibitors selected from sodium hexametaphosphate, sodium gluconate, sodium citrate, zinc dihydrogen phosphate, glucose or maltose.
According to another preferred embodiment of the present invention, in the step D, the amount of the corrosion inhibitor added is 1.0 to 8.0% by weight of the total weight of the concentrated solution.
The invention also relates to a liquid environment-friendly snow-melting agent or a solid environment-friendly snow-melting agent produced by the production method of the environment-friendly snow-melting agent.
According to a preferred embodiment of the invention, the liquid environment-friendly snow-melting agent contains 33-37% of calcium chloride, 3.5-7.0% of potassium acetate and 1.0-8.0% of corrosion inhibitor by weight of the total weight of the liquid environment-friendly snow-melting agent, and does not contain sodium chloride.
According to another preferred embodiment of the invention, the solid environment-friendly snow melting agent contains 72-74% of calcium chloride, 7-15% of potassium acetate and 2-15% of corrosion inhibitor based on the total weight of the solid environment-friendly snow melting agent, does not contain sodium chloride, and is solid spherical particles with the diameter of 3-6 mm.
The present invention will be described in more detail below.
The invention relates to a method for producing an environment-friendly snow melting agent by using cyclizing liquid generated in the production process of epichlorohydrin by a glycerol method.
In the production of epichlorohydrin by a glycerol method, the cyclization step is to perform dehydrochlorination and cyclization reactions on a dichloropropanol mixed solution generated by chlorohydrination reaction of glycerol in a reactive distillation tower under an alkaline condition to generate epichlorohydrin, and the generated epichlorohydrin is subjected to steam stripping by using water vapor. The product at the top of the reactive distillation tower is a crude product of epoxy chloropropane. Said dehydrochlorinating cyclization agent is Ca (OH)2Emulsion, taking part in dehydrochlorination reaction to generate CaCl2. In the dehydrochlorination cyclization reaction, side reactions may occur, the side reaction products are organic compounds containing chlorine such as glycerol mono-chlorohydrin, trichloropropane, unreacted dichloropropanol and a very small amount of epichlorohydrin which is not stripped, part of the organic compounds containing chlorine is hydrolyzed under alkaline conditions to produce glycerol, and dehydrochlorination cyclization agent Ca (OH)2The emulsion contains mainly calcium carbonate water-insoluble substances brought in by lime and unreacted and undissolved Ca (OH)2The solid formed together is also discharged from the bottom of the column, thus obtaining the cyclized liquid produced in the production process of epichlorohydrin by the glycerin method.
The production method of the environment-friendly snow-melting agent comprises the following steps:
A. solid-liquid separation
Carrying out solid-liquid separation on the cyclized solution to obtain a clear cyclized solution containing an organic compound;
the cyclization liquid-solid separation is mainly to remove calcium carbonate and undissolved Ca (OH)2And a small amount of insoluble substances such as iron-magnesium-aluminum oxide and silicate, so as to obtain a clear cyclized liquid. Therefore, the solid-liquid separation can obtain clear cyclized liquid containing organic compounds and filter cakes containing calcium carbonate, and the filter cakes can be used as a filling material of building materials after drying and dispersing treatment, such as the filling material for producing products such as air bricks or dry mortar additives; the clear cyclizing liquid containing the organic compound is a main raw material for producing the environment-friendly snow-melting agent.
The equipment used for the solid-liquid separation in the present invention is a plate-and-frame filter press or a microporous filter, which are currently commercially available products, such as a product sold under the trade name of a full-automatic plate-and-frame filter press by blue source mechanical filter press equipment ltd, and a product sold under the trade name of a microporous filter by apres filtration technology ltd, anhui.
The cyclization solution treated by the invention is CaCl by weight2A calcium chloride solution having a pH of 7 to 9 and containing 12 to 18% of glycerin, 1.5 to 1.0% of water-insoluble matter and 0.6 to 1.2% of a chlorine-containing organic compound;
wherein CaCl2The content is determined according to the analysis method of GB/T26520-2011 industrial calcium chloride; the glycerol content is determined by sodium periodate titration method GB/T132166-91; the content of the water-insoluble substances is determined according to the gravimetric method described in GB/T26520-2011 "determination of content of water-insoluble substances" in Industrial calcium chloride "; the pH was measured by the glass electrode method according to GB/T6904-2008 "measurement of pH in Industrial circulating Cooling Water and boiler Water".
In the cyclization solution treated by the invention, if CaCl is contained2If the content is less than 12%, the treatment capacity in the processes of catalytic oxidation and evaporation concentration is increased, and the cost for producing the snow-melting agent is increased; if CaCl2The content is higher than 18%, so that the effect of generating acetic acid by catalytic oxidation is influenced; thus, CaCl2The content is preferably 12-18%;
if the content of the glycerol is lower than 0.5%, the content of acetic acid generated by catalytic oxidation is too low, so that the content of potassium acetate in the snow-melting agent is too low, and the using effect of the snow-melting agent is influenced; if the content of the glycerol is higher than 1.0%, the conversion rate of organic compounds oxidized into acetic acid is reduced under the catalytic oxidation condition, so that the oxidation effect is influenced; therefore, a glycerol content of 0.5 to 1.0% is feasible;
if the content of the water-insoluble substance is less than 1.0% or more than 2.0%, the solid-liquid separation of the cyclized liquid is not facilitated; therefore, the content of water-insoluble matter is preferably 1.0 to 2.0%;
the chlorine-containing organic compound is glycerol mono-chlorohydrin (MCH), dichloropropanol (1,3-DCH), Epichlorohydrin (ECH) and Trichloropropane (TCP). The content of the chlorine-containing organic compound in the cyclizing liquid treated according to the present invention is usually 0.6 to 1.2% by weight as measured by gas chromatography. The content of the chlorine-containing organic compound exceeding the above range is not preferable because the content of the chlorine-containing organic compound is less than 0.6%, the amount of acetic acid generated by catalytic oxidation is too small, and the content of potassium acetate in the produced snow-melting agent is too small, resulting in poor ice-melting effect of the snow-melting agent; if the content of the chlorine-containing organic compound is higher than 1.2%, the chlorine-containing organic compound cannot be completely oxidized under the catalytic oxidation condition of the invention, so that the chlorine-containing organic compound is remained in the snow-melting agent product, thereby affecting the quality of the snow-melting agent product, and the snow-melting agent product pollutes the environment after being used, which is not beneficial to environmental protection.
The treatment of the present invention with the cyclized liquid having a pH exceeding the above range is not preferable because the cyclized liquid has a pH of less than 7, and the organic compound is easily oxidized to carbon dioxide and water to a high degree, resulting in poor selectivity of the conversion of the organic compound into acetic acid and a low concentration of acetic acid; when the pH of the cyclized solution is greater than 9, carbon dioxide in the air reacts with Ca (OH) in the solution under the condition of air-introduced oxidation2The reaction produces calcium carbonate, thus leading to fouling and plugging of the oxidation system.
B. Catalytic oxidation treatment
Step A, carrying out catalytic oxidation treatment on the clear cyclized liquid containing the organic compound to obtain a calcium chloride solution containing acetic acid;
according to the invention, the catalytic oxidation treatment of the clear cyclized liquid is mainly aimed at completely oxidizing organic matters in the clear cyclized liquid into acetic acid and only oxidizing a small part of the organic matters into carbon dioxide and water under the controlled oxidation condition.
In the invention, the catalytic oxidation is an advanced oxidation reaction of organic wastewater which is carried out by taking air as an oxidant and taking ferric chloride or ferrous chloride as a catalyst. The advanced oxidation of organic wastewater is a typical wastewater treatment project. The engineer in the field knows that the mechanism of advanced oxidation treatment of organic wastewater is that when oxygen-containing gas exists in wastewater as hydroxyl radical, the organic matter undergoes a series reaction of producing simple carboxylic acid from complex organic matter and then deeply oxidizing into carbon dioxide and water, and in the process, the simple carboxylic acid is a relatively stable intermediate product. The method controls the depth of the series reaction, mainly controls the catalytic oxidation condition to selectively convert organic matters in the wastewater into carboxylic acid in the oxidation process, and the carboxylic acid can not be deeply oxidized into carbon dioxide and water under the catalytic oxidation condition.
In the present invention, the clear cyclized liquid containing an organic compound is subjected to wet air catalytic oxidation treatment for 0.5 to 1.5 hours using air under a pressure of 0.5 to 2.5MPa and a temperature of 100 to 180 ℃.
When the temperature and the time of the catalytic oxidation reaction are in the range, if the pressure of the catalytic oxidation reaction is lower than 0.5MPa, the solution is gasified at the temperature, and the solubility of oxygen in the air in water is influenced, so that the oxidation effect is influenced; if the pressure of the catalytic oxidation reaction is higher than 2.5MPa, most of organic matters in the clear cyclization liquid can be completely oxidized, and the concentration of acetic acid is influenced; therefore, it is reasonable that the pressure of the catalytic oxidation reaction is 0.5 to 2.5MPa, preferably 0.8 to 2.2MPa, more preferably 1.2 to 1.8 MPa;
likewise, when the pressure and time of the catalytic oxidation reaction are within the stated ranges, if the temperature of the catalytic oxidation reaction is below 100 ℃, then most of the organic matter in the clear cyclization serum will not be oxidized; if the temperature of the catalytic oxidation reaction is higher than 180 ℃, most organic matters in the clear cyclization clear solution can be completely oxidized; therefore, the temperature of the catalytic oxidation reaction is suitably 100 to 180 ℃, preferably 120 to 160 ℃, and more preferably 130 to 150 ℃;
when the pressure and temperature of the catalytic oxidation reaction are in the above range, if the time of the catalytic oxidation reaction is shorter than 0.5h, most of the organic matters in the clear cyclization clear solution are not oxidized; if the time of the catalytic oxidation reaction is longer than 1.5h, most of organic matters in the clear cyclized clear liquid are completely oxidized; therefore, the time of the catalytic oxidation reaction is suitably 0.5 to 1.5 hours, preferably 0.8 to 1.2 hours, more preferably 0.9 to 1.0 hour;
preferably, the clear cyclized liquid containing the organic compound is subjected to wet air catalytic oxidation treatment for 0.8 to 1.2 hours by using air under the conditions of the pressure of 0.8 to 2.2MPa and the temperature of 120 to 160 ℃.
More preferably, the clear cyclized liquid containing the organic compound is subjected to wet air catalytic oxidation treatment for 0.9 to 1.0 hour by using air under the conditions of a pressure of 1.2 to 1.8MPa and a temperature of 130 to 150 ℃.
The apparatus used for the wet air catalytic oxidation treatment is an apparatus generally used in the chemical technical field and sold on the market at present, such as an apparatus sold under the trade name of Fenton oxidation tower by Shandong Kofibrate environmental protection Equipment Co., Ltd or an apparatus sold under the trade name of high efficiency multi-catalytic oxidation tower by Shandong Aibi environmental protection science and technology Co., Ltd.
In the obtained solution containing calcium chloride acetate, the subsequent treatment can be carried out when the content of acetic acid reaches 1.5-3.0%, because the content range of the acetic acid is an important index for selective oxidation of organic matters in the cyclized clear liquid.
The method for measuring the acetic acid content comprises the following steps: analyzing the content of acetate ions by adopting a conventional high performance liquid chromatography, and then converting the content of the acetate ions into the content of acetic acid.
C. Aqueous potassium hydroxide solution treatment
B, treating the calcium chloride solution containing acetic acid with a potassium hydroxide aqueous solution until the pH value is 6-9 to obtain a calcium chloride solution containing potassium acetate;
the main purpose of the treatment with the potassium hydroxide aqueous solution is to neutralize acetic acid in the calcium chloride solution into potassium acetate, which is a main component constituting the environment-friendly snow-melting agent.
In the invention, the calcium chloride solution containing acetic acid is treated by the potassium hydroxide aqueous solution until the pH value is 6-9, which meets the index requirement specified in table 1 in GB/T23851 and 2009 road deicing and snow melting agent, so that the pH value of the calcium chloride solution treated by the potassium hydroxide aqueous solution is suitably 6-9, preferably 6.5-8.2.
In the invention, the content of potassium acetate in the calcium chloride solution is measured by adopting a conventional high performance liquid chromatography, and then the content of the potassium acetate is obtained by converting the content of the acetate ions.
D. Concentrating by evaporation
And C, evaporating and concentrating the calcium chloride solution containing potassium acetate, adding a corrosion inhibitor into the obtained concentrated solution to obtain a liquid environment-friendly snow-melting agent, or treating the liquid environment-friendly snow-melting agent by a granulation drying system to obtain a solid environment-friendly snow-melting agent.
According to the invention, the basic purpose of evaporation concentration of the potassium acetate-containing calcium chloride solution is to increase the salt concentration in the solution and lower the freezing point, and the obtained liquid snow-melting agent product is easy to store at low temperature.
The conditions for the evaporative concentration were as follows: temperature of 65-150 ℃, pressure of 30-400 KPa. The equipment used for the evaporative concentration is a product currently marketed, for example, an evaporation equipment sold under the trade name of multi-effect evaporator by biconic environmental protection equipment ltd.
And (3) evaporating and concentrating the calcium chloride solution containing potassium acetate until the content of calcium chloride is 33-37% by weight. If the content of calcium chloride evaporated and concentrated is lower than 33 percent, the transportation amount of the liquid snow-melting agent product is large; if the calcium chloride content of the evaporation concentration is higher than 37%, the liquid snow-melting agent product can crystallize; therefore, the content of calcium chloride concentrated by evaporation is preferably 33-37%;
in the context of the present invention, a corrosion inhibitor is understood to be a compound which has the effect of preventing or slowing the corrosion of materials.
The main purpose of adding the corrosion inhibitor into the concentrated solution is to reduce the corrosion of the snow-melting agent to basic equipment.
According to the invention, the corrosion inhibitor is one or more corrosion inhibitors selected from sodium hexametaphosphate, sodium gluconate, sodium citrate, zinc dihydrogen phosphate, glucose or maltose. They are all products currently marketed, for example by Suzhou such as Nichikura chemical Co., Ltd under the trade name sodium hexametaphosphate, by Suzhou Jielano chemical Co., Ltd under the trade name sodium gluconate, and by Hunan Virginia Biotech Co., Ltd under the trade name maltose.
According to the invention, the addition amount of the corrosion inhibitor is 1.0-8.0% of the total weight of the concentrated solution. If the addition amount of the corrosion inhibitor is less than 1.0 percent, the corrosion inhibition effect is poor; if the addition amount of the corrosion inhibitor is more than 8.0 percent, the corrosion inhibition rate is not greatly influenced, and the cost is increased; therefore, the amount of the corrosion inhibitor added is 1.0 to 8.0%, preferably 2.0 to 6.0%, and more preferably 3.0 to 5.0%.
And adding a corrosion inhibitor into the concentrated solution to obtain the liquid environment-friendly snow-melting agent.
And (3) treating the liquid environment-friendly snow-melting agent by using a granulation drying system under the conditions of double-effect evaporation concentration and spray fluidized bed granulation to obtain the solid environment-friendly snow-melting agent. The granulation drying system used in the present invention is a product currently marketed, for example, a granulation drying system sold under the trade name of anhydrous calcium chloride granulation kit by Shandong-Hua-Heat engineering Co.
The invention also relates to a liquid environment-friendly snow-melting agent or a solid environment-friendly snow-melting agent produced by the production method of the environment-friendly snow-melting agent.
The liquid environment-friendly snow-melting agent contains 33-37% of calcium chloride, 3.5-7.0% of potassium acetate and 1.0-8.0% of corrosion inhibitor based on the total weight of the liquid environment-friendly snow-melting agent, and does not contain sodium chloride;
the solid environment-friendly snow-melting agent contains 72-74% of calcium chloride, 7-15% of potassium acetate and 2.0-15.0% of corrosion inhibitor by weight of the total weight of the solid environment-friendly snow-melting agent, does not contain sodium chloride, and is solid spherical particles with the diameter of 3-6 mm.
[ advantageous effects ]
The invention has the beneficial effects that: the liquid environment-friendly snow-melting agent and the solid environment-friendly snow-melting agent completely meet the regulations of GB/T23851-. The method for producing the environment-friendly snow melting agent by using the cyclizing liquid generated in the production process of the epichlorohydrin by the glycerol method has the advantages of simple and convenient process flow, easy operation and control, effective utilization of waste resources, obvious social and economic benefits and environmental friendliness.
[ detailed description ] embodiments
The invention will be better understood from the following examples.
Example 1: production of liquid environment-friendly snow-melting agent from cyclizing liquid
The implementation steps of this example are as follows:
A. solid-liquid separation
CaCl was measured in weight using a product sold under the trade name full-automatic plate and frame filter press by blue-source mechanical filter press equipment, Inc2Performing solid-liquid separation on cyclized solution of calcium chloride solution with pH 7, which contains 12% of glycerol, 1.0% of water insoluble substances and 0.6% of chlorinated organic compounds, to obtain clear cyclized solution containing organic compounds;
B. catalytic oxidation treatment
Using equipment sold under the trade name of a high-efficiency multi-element catalytic oxidation tower by Shandong Aibi environmental protection science and technology Limited, performing wet air catalytic oxidation treatment on the clear cyclization solution containing the organic compound for 1.5h by using air under the conditions that the pressure is 0.5MPa and the temperature is 100 ℃ to obtain a calcium chloride solution containing acetic acid;
C. aqueous potassium hydroxide solution treatment
B, treating the calcium chloride solution containing acetic acid by using a potassium hydroxide aqueous solution with the concentration of 5 percent by weight until the pH value is 9.0 to obtain a calcium chloride solution containing potassium acetate;
D. concentrating by evaporation
Step C, performing five-effect evaporation concentration on a calcium chloride solution containing potassium acetate by using evaporation equipment sold by Bicheng environmental protection equipment Limited company in New county under the conditions of 65-150 ℃ and 30-400 KPa until the content of calcium chloride is 37% by weight, adding 8.0% of sodium hexametaphosphate corrosion inhibitor by the total weight of the concentrated solution into the obtained concentrated solution to obtain a liquid environment-friendly snow melting agent, and determining according to the analysis method described in the specification, wherein the liquid environment-friendly snow melting agent contains 37% of calcium chloride, 3.5% of potassium acetate and 8.0% of corrosion inhibitor by the total weight of the liquid environment-friendly snow melting agent and does not contain sodium chloride;
the results of the analysis of the products associated with the various steps of this example are shown in Table 1.
Table 1: the results of analysis of the products associated with each step of this example
Example 2: production of liquid environment-friendly snow-melting agent from cyclizing liquid
The implementation steps of this example are as follows:
A. solid-liquid separation
CaCl will be measured in weight using a product sold under the trade name microporous Filter by the Anhui Precise filtration technology Ltd2Carrying out solid-liquid separation on the cyclized solution of the calcium chloride solution with the pH value of 7.5, the content of which is 14 percent, the content of glycerin is 0.8 percent, the content of water-insoluble substances is 1.5 percent and the content of chlorine-containing organic compounds is 0.9 percent to obtain a clear cyclized solution containing organic compounds;
B. catalytic oxidation treatment
Using equipment sold under the trade name of Fenton oxidation tower by Shandong Kebei environmental protection Equipment GmbH, step A, the clear cyclization solution containing the organic compound is subjected to wet air catalytic oxidation treatment for 1.0h by using air under the conditions of pressure of 1.0MPa and temperature of 150 ℃ to obtain a calcium chloride solution containing acetic acid;
C. aqueous potassium hydroxide solution treatment
B, treating the calcium chloride solution containing acetic acid by using a potassium hydroxide aqueous solution with the concentration of 8 percent by weight until the pH value is 6.0 to obtain a calcium chloride solution containing potassium acetate;
D. concentrating by evaporation
And C, performing five-effect evaporation and concentration on the calcium chloride solution containing potassium acetate by using evaporation equipment sold by Bicheng environmental protection equipment Limited company in New rural province under the conditions of 65-150 ℃ and 30-400 KPa until the content of calcium chloride is 35% by weight, adding 2.0% of sodium gluconate corrosion inhibitor by the total weight of the concentrated solution into the obtained concentrated solution to obtain the liquid environment-friendly snow-melting agent, and determining according to the analysis method described in the specification, wherein the liquid environment-friendly snow-melting agent contains 35% of calcium chloride, 4.5% of potassium acetate and 2.0% of corrosion inhibitor by the total weight of the liquid environment-friendly snow-melting agent and does not contain sodium chloride. The results of the analysis of the products associated with the various steps of this example are shown in Table 2.
Table 2: the results of analysis of the products associated with each step of this example
Example 3: production of liquid environment-friendly snow-melting agent from cyclizing liquid
The implementation steps of this example are as follows:
A. solid-liquid separation
CaCl was measured in weight using a plate and frame filter press sold under the trade name full-automatic plate and frame filter press by blue-source mechanical filter press equipment, Inc2Carrying out solid-liquid separation on the cyclized solution of the calcium chloride solution with the pH value of 8.6, the content of which is 12 percent, the content of glycerin is 1.0 percent, the content of water-insoluble substances is 1.4 percent and the content of chlorinated organic compounds is 1.2 percent to obtain a clear cyclized solution containing organic compounds;
B. catalytic oxidation treatment
Using equipment sold under the trade name of Fenton oxidation tower by Shandong Kebei environmental protection Equipment GmbH, the clear cyclized liquid containing the organic compound in the step A is subjected to wet air catalytic oxidation treatment for 0.8h by using air under the conditions of the pressure of 2.0MPa and the temperature of 160 ℃ to obtain a calcium chloride solution containing acetic acid;
C. aqueous potassium hydroxide solution treatment
B, treating the calcium chloride solution containing acetic acid by using a potassium hydroxide aqueous solution with the concentration of 12 percent by weight until the pH value is 7.0 to obtain a calcium chloride solution containing potassium acetate;
D. concentrating by evaporation
And C, performing five-effect evaporation and concentration on the calcium chloride solution containing potassium acetate by using evaporation equipment sold by Bicheng environmental protection equipment Limited company in New rural area under the conditions of 65-150 ℃ and 30-400 KPa until the content of calcium chloride is 33% by weight, adding 4.0% of sodium citrate corrosion inhibitor by the total weight of the concentrated solution into the obtained concentrated solution to obtain the liquid environment-friendly snow-melting agent, and determining according to the analysis method described in the specification, wherein the liquid environment-friendly snow-melting agent contains 33% of calcium chloride, 7% of potassium acetate and 4.0% of corrosion inhibitor by the total weight of the liquid environment-friendly snow-melting agent and does not contain sodium chloride.
The results of the analysis of the products associated with the various steps of this example are shown in Table 3.
Table 3: the results of analysis of the products associated with each step of this example
Example 4: production of solid environment-friendly snow-melting agent from cyclizing liquid
The implementation steps of this example are as follows:
A. solid-liquid separation
CaCl was measured in weight using a plate and frame filter press sold under the trade name full-automatic plate and frame filter press by blue-source mechanical filter press equipment, Inc2Performing solid-liquid separation on cyclized solution of calcium chloride solution with pH of 8.2, the content of which is 18%, the content of glycerol is 0.8%, the content of water-insoluble substances is 2.0%, and the content of chlorinated organic compounds is 0.8%, to obtain clear cyclized solution containing organic compounds;
B. catalytic oxidation treatment
Using equipment sold under the trade name of a high-efficiency multi-element catalytic oxidation tower by Shandong Aibi environmental protection science and technology Limited, carrying out wet air catalytic oxidation treatment on the clear cyclization solution containing the organic compound in the step A for 0.5h by using air under the conditions of the pressure of 2.5MPa and the temperature of 180 ℃ to obtain a calcium chloride solution containing acetic acid;
C. aqueous potassium hydroxide solution treatment
B, treating the calcium chloride solution containing acetic acid by using a potassium hydroxide aqueous solution with the concentration of 15 percent by weight until the pH value is 8.0 to obtain a calcium chloride solution containing potassium acetate;
D. concentrating by evaporation
Step C, performing five-effect evaporation concentration on the calcium chloride solution containing potassium acetate by using evaporation equipment sold by Bicheng environmental protection equipment Limited company in New county under the conditions of 65-150 ℃ and 30-400 KPa until the content of calcium chloride is 36% by weight, adding 7.5% of zinc dihydrogen phosphate corrosion inhibitor by the total weight of the concentrated solution into the obtained concentrated solution to obtain a liquid environment-friendly snow-melting agent, and determining according to the analysis method described in the specification, wherein the liquid environment-friendly snow-melting agent contains 36% of calcium chloride, 3.5% of potassium acetate and 7.5% of corrosion inhibitor by the total weight of the liquid environment-friendly snow-melting agent, and does not contain sodium chloride;
a granulation drying system sold by Shandong Hua thermal engineering Limited company under the trade name of anhydrous calcium chloride granulation complete equipment allows the liquid environment-friendly snow-melting agent to obtain the solid environment-friendly snow-melting agent under the conditions of double-effect evaporation concentration and spray fluidized bed granulation. The solid environment-friendly snow-melting agent contains 72 percent of calcium chloride, 7 percent of potassium acetate and 15 percent of corrosion inhibitor based on the total weight of the solid environment-friendly snow-melting agent, and is solid spherical particles with the diameter of 3-6 mm. The results of the analysis of the products associated with the various steps of this example are shown in Table 4.
Table 4: the results of analysis of the products associated with each step of this example
Example 5: production of solid environment-friendly snow-melting agent from cyclizing liquid
The implementation steps of this example are as follows:
A. solid-liquid separation
CaCl by weight was measured using a plate and frame filter press sold under the trade name full-automatic plate and frame filter press by blue-source mechanical filter press equipment, Inc., or a microporous filter sold under the trade name microporous filter by Aphan's Progress filtration technology, Inc2Carrying out solid-liquid separation on cyclized liquid of calcium chloride solution with the content of 12%, the content of glycerin of 1.0%, the content of water insoluble substance of 1.2% and the content of chlorinated organic compound of pH9.0 to obtain clear cyclized liquid containing organic compound;
B. catalytic oxidation treatment
Using equipment sold under the trade name of Fenton oxidation tower by Shandong Kebei environmental protection Equipment GmbH, the clear cyclized liquid containing the organic compound in the step A is subjected to wet air catalytic oxidation treatment for 1.0h by using air under the conditions of the pressure of 2.0MPa and the temperature of 150 ℃ to obtain a calcium chloride solution containing acetic acid;
C. aqueous potassium hydroxide solution treatment
B, treating the calcium chloride solution containing acetic acid by using a potassium hydroxide aqueous solution with the concentration of 10 percent by weight until the pH value is 6.5 to obtain a calcium chloride solution containing potassium acetate;
D. concentrating by evaporation
Step C, performing five-effect evaporation concentration on the calcium chloride solution containing potassium acetate by using evaporation equipment sold by Bicheng environmental protection equipment Limited company in New county under the conditions of 65-150 ℃ and 30-400 KPa until the content of calcium chloride is 34.6% by weight, adding 5.0% of glucose corrosion inhibitor by the total weight of the concentrated solution into the obtained concentrated solution to obtain a liquid environment-friendly snow-melting agent, and determining according to the analysis method described in the specification, wherein the liquid environment-friendly snow-melting agent contains 34.6% of calcium chloride, 7.0% of potassium acetate and 5.0% of corrosion inhibitor by the total weight of the liquid environment-friendly snow-melting agent and does not contain sodium chloride;
a granulation drying system sold by Shandong Hua thermal engineering Limited company under the trade name of anhydrous calcium chloride granulation complete equipment allows the liquid environment-friendly snow-melting agent to obtain the solid environment-friendly snow-melting agent under the conditions of double-effect evaporation concentration and spray fluidized bed granulation. The solid environment-friendly snow melting agent contains 74 percent of calcium chloride, 15 percent of potassium acetate and 10 percent of corrosion inhibitor based on the total weight of the solid environment-friendly snow melting agent, and is solid spherical particles with the diameter of 3-6 mm. The results of the analysis of the products associated with the various steps of this example are shown in Table 5.
Table 5: the results of analysis of the products associated with each step of this example
Example 6: production of solid environment-friendly snow-melting agent from cyclizing liquid
The implementation steps of this example are as follows:
A. solid-liquid separation
CaCl was measured in weight using a microfilter sold under the trade name microfilter by Aprepris filtration technology, Inc., Anhui2Performing solid-liquid separation on the cyclized solution of the calcium chloride solution with the pH value of 7.6, the content of which is 15 percent, the content of glycerin is 0.6 percent, the content of water-insoluble substances is 1.8 percent and the content of chlorine-containing organic compounds is 0.8 percent to obtain a clear cyclized solution containing organic compounds;
B. catalytic oxidation treatment
Using equipment sold under the trade name of a high-efficiency multi-element catalytic oxidation tower by Shandong Aibi environmental protection science and technology Limited, performing wet air catalytic oxidation treatment on the clear cyclization solution containing the organic compound for 1.3h by using air under the conditions that the pressure is 0.8MPa and the temperature is 120 ℃ to obtain a calcium chloride solution containing acetic acid;
C. aqueous potassium hydroxide solution treatment
B, treating the calcium chloride solution containing acetic acid by using a potassium hydroxide aqueous solution with the concentration of 14 percent by weight until the pH value is 8.2 to obtain a calcium chloride solution containing potassium acetate;
D. concentrating by evaporation
Step C, performing five-effect evaporation concentration on a calcium chloride solution containing potassium acetate by using evaporation equipment sold by Bicheng environmental protection equipment Limited company in New county under the conditions of 65-150 ℃ and 30-400 KPa until the content of calcium chloride is 34% by weight, adding 1.0% maltose corrosion inhibitor into the obtained concentrated solution by the total weight of the concentrated solution to obtain a liquid environment-friendly snow-melting agent, and determining according to the analysis method described in the specification, wherein the liquid environment-friendly snow-melting agent contains 34% of calcium chloride, 3.5% of potassium acetate and 1.0% of corrosion inhibitor by the total weight of the liquid environment-friendly snow-melting agent and does not contain sodium chloride;
a granulation drying system sold by Shandong Hua thermal engineering Limited company under the trade name of anhydrous calcium chloride granulation complete equipment allows the liquid environment-friendly snow-melting agent to obtain the solid environment-friendly snow-melting agent under the conditions of double-effect evaporation concentration and spray fluidized bed granulation. The solid environment-friendly snow melting agent contains 74 percent of calcium chloride, 7.9 percent of potassium acetate and 2.0 percent of corrosion inhibitor based on the total weight of the solid environment-friendly snow melting agent, and the solid environment-friendly snow melting agent is solid spherical particles with the diameter of 3-6 mm. The results of the analysis of the products associated with the various steps of this example are shown in Table 6.
Table 6: the results of analysis of the products associated with each step of this example
Test example 1:
the test mode of this test example is as follows:
the snow and ice melting capabilities of the liquid environment-friendly snow melting agent and the solid environment-friendly snow melting agent prepared in examples 1-6 were tested according to the method and the steps specified in the determination of the snow and ice melting capabilities of the GB/T23851 and 2017 snow melting agent 6.5.3.2.2 type II snow melting agent. The results of these tests are listed in table 7.
Table 7: the invention relates to a relative snow-melting and ice-thawing capability test result of an environment-friendly snow-melting agent
In the table: the relative snow and ice melting capacity is calculated according to the following formula:
the test result of the test example 1 shows that the relative snow-melting and ice-thawing capacity of the snow-melting agent product produced by the method can meet the index requirement that the relative snow-melting and ice-thawing capacity is more than or equal to 90% specified in table 1 of GB/T23851 and 2017 snow-melting agent.
Test example 2: carbon steel corrosion rate test
The test mode of this test example is as follows:
the carbon steel corrosion rates of the liquid environment-friendly snow-melting agent and the solid environment-friendly snow-melting agent prepared in examples 1-6 were tested according to the method and the steps specified in the carbon steel corrosion rate of GB/T23851 and 2017 snow-melting agent 6.8. The results of these tests are listed in table 8.
Table 8: the invention relates to a carbon steel corrosion rate test result of an environment-friendly snow-melting agent
The test result of the embodiment 6 shows that the carbon steel corrosion rates of the liquid environment-friendly snow-melting agent and the solid environment-friendly snow-melting agent prepared in the embodiments 1-6 of the invention can meet the index requirement that the carbon steel corrosion rate is less than or equal to 0.11mm/a specified in GB/T23851 and 2017 snow-melting agent in Table 1.
Claims (9)
1. The method for producing the environment-friendly snow melting agent from the cyclized liquid generated in the production process of epichlorohydrin by a glycerol method is characterized by comprising the following steps:
A. solid-liquid separation
Carrying out solid-liquid separation on the cyclized solution to obtain a clear cyclized solution containing an organic compound;
the cyclizing solution is CaCl by weight2A calcium chloride solution having a pH of 7 to 9 and containing 12 to 18% of glycerin, 1.5 to 1.0% of water-insoluble matter and 0.6 to 1.2% of a chlorine-containing organic compound; the chlorine-containing organic compound is glycerol mono-chlorohydrin, dichloropropanol, epichlorohydrin and trichloropropane;
B. catalytic oxidation treatment
Step A, carrying out catalytic oxidation treatment on the clear cyclized liquid containing the organic compound to obtain a calcium chloride solution containing acetic acid;
C. aqueous potassium hydroxide solution treatment
B, treating the calcium chloride solution containing acetic acid with a potassium hydroxide aqueous solution until the pH value is 6-9 to obtain a calcium chloride solution containing potassium acetate;
D. concentrating by evaporation
And C, evaporating and concentrating the calcium chloride solution containing potassium acetate, adding a corrosion inhibitor into the obtained concentrated solution to obtain a liquid environment-friendly snow-melting agent, or treating the liquid environment-friendly snow-melting agent product by a granulation drying system to obtain a solid environment-friendly snow-melting agent.
2. The method for producing an environment-friendly snow-melting agent as defined in claim 1, wherein in the step A, solid-liquid separation is carried out using a plate-and-frame filter press or a microporous filter.
3. The method for producing an environment-friendly snow-melting agent as claimed in claim 1, wherein in the step B, wet air catalytic oxidation treatment is performed for 0.5 to 1.5 hours by using air under the conditions of a pressure of 0.5 to 2.5MPa and a temperature of 100 to 180 ℃.
4. The method for producing an environment-friendly snow-melting agent as claimed in claim 1, wherein in step D, the calcium chloride solution containing potassium acetate is evaporated and concentrated to a calcium chloride content of 33 to 37% by weight.
5. The method for producing an environment-friendly snow melt agent as claimed in claim 1, wherein in the step D, the corrosion inhibitor is one or more corrosion inhibitors selected from sodium hexametaphosphate, sodium gluconate, sodium citrate, zinc dihydrogen phosphate, glucose or maltose.
6. The method for producing an environment-friendly snow-melting agent as claimed in claim 1, wherein in the step D, the amount of the corrosion inhibitor added is 1.0-8.0% by weight of the total weight of the concentrated solution.
7. The liquid environment-friendly snow-melting agent or the solid environment-friendly snow-melting agent produced by the production method of the environment-friendly snow-melting agent according to any one of claims 1 to 6.
8. The environment-friendly snow-melting agent as claimed in claim 7, wherein the liquid environment-friendly snow-melting agent comprises 33-37% of calcium chloride, 3.5-7.0% of potassium acetate and 1.0-8.0% of corrosion inhibitor by weight of the total weight of the liquid environment-friendly snow-melting agent, and does not contain sodium chloride.
9. The environment-friendly snow-melting agent as claimed in claim 7, wherein the solid environment-friendly snow-melting agent comprises 72-74% of calcium chloride, 7-15% of potassium acetate and 2-15% of corrosion inhibitor by weight of the total solid environment-friendly snow-melting agent, and the solid environment-friendly snow-melting agent is solid spherical particles with a diameter of 3-6 mm and does not contain sodium chloride.
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