Oxidized kitchen waste grease composite coal flotation agent and preparation method thereof

Abstract

The invention discloses an oxidized kitchen waste grease composite coal flotation agent and a preparation method thereof. The oxidized kitchen waste grease composite coal flotation agent consists of the following components in parts by weight: 30-40 parts of oxidized kitchen waste grease, 20-30 parts of kerosene, 3 parts of oleic acid, 3 parts of sodium oleate, 4 parts of methyl octanoate, 5 parts of dodecyl polyoxyethylene ether and 15-35 parts of water. The preparation process is simple, and the defect of poor stability of the existing composite agent is overcome. The composite agent can maintain long-term stability without stratification at room temperature, does not require additional dispersing and emulsifying equipment, is simple and flexible to use, has a small amount of use, and has obvious effect.

Description

Technical Field

[0001] The invention relates to the technical field of preparation of coal flotation agents, and in particular to an oxidized kitchen waste grease composite coal flotation agent and a preparation method thereof. Background Art

[0002] Flotation is an effective means of sorting fine coal. The flotation process of coal preparation is a complex process involving solution interface chemistry and fluid dynamics. The selection and use of flotation agents are important factors affecting the flotation effect of coal preparation. Commonly used flotation agents for coal preparation include collectors and frothers, as well as some auxiliary agents, such as flocculants and inhibitors. At present, most of the research on flotation agents in China is focused on the synthesis, development and application of high-efficiency frothers, and the research and development of collectors is still in its infancy. In general coal preparation plants, kerosene, light diesel oil, etc. are used as collectors for coal slime flotation. The characteristics of this type of collector are strong hydrophobicity, wide sources, easy preparation, and more experience in use. However, this type of collector has poor dispersibility in coal slime water, large agent consumption, and poor economic benefits. For coal with a high content of fine coal and low metamorphicity, due to its poor floatability and selectivity, the flotation agent consumption is greater. The amount of hydrocarbon oil used in coal flotation is generally 1-2 kg / t. With the rise in oil prices, the cost of flotation reagents will also increase significantly, leading to an increase in flotation costs, which will ultimately affect the economic benefits of coal preparation plants. Therefore, improving reagent performance, reducing reagent dosage, and developing new, efficient, and low-cost synthetic flotation reagents are inevitable development trends in the flotation field.

[0003] Composite flotation agents are a new trend in the development of flotation agents. They have both efficient foaming and collection performance, strong adaptability, fast flotation speed, easy use, and easy automatic control. However, the types of composite flotation agents currently available for coal flotation are too few, the preparation process is complex, the collection performance is not strong, and the stability is poor. They cannot meet the requirements of flotation production in various coal preparation plants, which greatly limits their promotion and application. Therefore, the research of new composite coal flotation agents with low cost, stable performance and excellent performance is of great significance to the further development of the coal flotation field and the construction of a resource-saving society. Summary of the invention

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] The invention provides an oxidized kitchen waste grease composite coal flotation agent, which consists of the following components in parts by weight: 30-40 parts of oxidized kitchen waste grease, 20-30 parts of kerosene, 3 parts of oleic acid, 3 parts of sodium oleate, 4 parts of methyl octanoate, 5 parts of dodecyl polyoxyethylene ether and 15-35 parts of water.

[0006] Preferably, it is composed of the following components in parts by weight: 30 parts of oxidized kitchen waste oil, 30 parts of kerosene, 3 parts of oleic acid, 3 parts of sodium oleate, 4 parts of methyl caprylate, 5 parts of dodecyl polyoxyethylene ether and 25 parts of water.

[0007] Preferably, it is composed of the following components in parts by weight: 40 parts of oxidized kitchen waste grease, 20 parts of kerosene, 3 parts of oleic acid, 3 parts of sodium oleate, 4 parts of methyl octanoate, 5 parts of dodecyl polyoxyethylene ether and 25 parts of water.

[0008] The present invention also provides a method for preparing the above-mentioned medicament, characterized in that it comprises the following steps:

[0009] (1) oxidizing the waste cooking oil by supercritical oxidation technology to obtain oxidized waste cooking oil;

[0010] (2) Under magnetic stirring, add kerosene, oleic acid, sodium oleate, methyl octanoate, dodecyl polyoxyethylene ether and oxidized kitchen waste oil into the reaction container in order according to the proportion, and stir for 5 minutes;

[0011] (3) The temperature and pressure of the reaction are increased, water is used as the supercritical reaction medium, water is prepared into a supercritical fluid under supercritical technology, and the composite flotation agent raw materials are subjected to supercritical mixed emulsification treatment. After the treatment is completed, an emulsified oil-soluble composite coal flotation agent can be obtained.

[0012] Preferably, the supercritical oxidation time during oxidation in step (1) is 5-10 min.

[0013] Preferably, the critical pressure during the preparation of the supercritical fluid in step (3) is 22.1 MPa, and the critical temperature is 374°C.

[0014] Preferably, the time for supercritical mixing emulsification treatment in step (3) is 15 min.

[0015] The beneficial effects of the present invention are:

[0016] 1. The present invention adopts kerosene, a hydrocarbon oil with strong hydrophobicity, as a part of the collector composition. The kerosene component has carbon chains of different lengths, so it has strong selectivity. When used in combination with fatty alcohol polyvinyl ether with good foaming performance, the performance of the flotation agent can be greatly enhanced. At the same time, a new type of composite flotation agent is obtained by supercritical mixed emulsification technology. The preparation process is simple, does not involve complicated operations, and is easy to promote industrialization.

[0017] 2. The present invention is realized under supercritical technology. Under this condition, supercritical water has great compressibility, its own diffusion coefficient increases by 7 to 24 times, the dispersibility of the solution is greatly improved, it has good performance of dissolving other substances, and can form a new type of emulsion composite coal flotation agent with long-term stable existence.

[0018] 3. The present invention utilizes supercritical oxidation to oxidize waste cooking oil to produce a large amount of saturated and unsaturated fatty acids. These fatty acids have a wide hydrocarbon chain range, a large capture range, good hydrophobicity, and strong capture ability. Under the promotion of supercritical water, the unsaturated bonds in the fatty acids are converted into corresponding saturated bonds, thereby enhancing their capture ability. The above-mentioned capture agent and kerosene are used in combination, which can, on the one hand, play a synergistic role and reduce the amount of kerosene, thereby saving the amount of fossil energy; on the other hand, the waste cooking oil is effectively decomposed, which can avoid environmental pollution and reduce food safety threats.

[0019] 4. Compared with the existing composite agents, the new composite flotation agent prepared by the present invention has more efficient foaming, better collection performance, strong anti-sludge ability, stable properties, non-sticky foam and easy dissipation, strong adaptability, fast flotation speed, simple agent preparation, and a wide range of raw material sources. It overcomes the defect of poor stability of existing composite agents and can remain stable for a long time without stratification at room temperature.

[0020] 5. The novel composite coal flotation agent prepared by the present invention can be directly added in practical applications without the need for additional dispersing and emulsifying equipment. It is easy and flexible to use, requires a small amount, and has an obvious effect. DETAILED DESCRIPTION

[0021] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] The experimental methods in the following examples without specifying specific conditions were all carried out according to conventional methods and conditions in the art, and the materials used were all commercially available unless otherwise specified. Example

[0023] A composite coal flotation agent, the preparation raw materials of which are composed of the following components in parts by weight: 30 parts of oxidized kitchen waste grease, 30 parts of kerosene, 3 parts of oleic acid, 3 parts of sodium oleate, 4 parts of methyl octanoate, 5 parts of dodecyl polyoxyethylene ether and 25 parts of water.

[0024] Follow the steps below to implement it:

[0025] Step 1: Oxidize the waste cooking oil by supercritical oxidation technology. After oxidation, the waste cooking oil will produce a large amount of fatty acids, which can be used as one of the raw materials for preparing composite coal flotation agents. The supercritical oxidation time is 5-10 minutes.

[0026] Step 2: Under magnetic stirring, add kerosene, oleic acid, sodium oleate, methyl octanoate, dodecyl polyoxyethylene ether and oxidized kitchen waste oil into a reaction container in order according to the proportion, and stir for 5 minutes;

[0027] Step 3, increasing the temperature and pressure of the reaction, using water as a supercritical reaction medium, preparing water into a supercritical fluid under supercritical conditions, and subjecting the raw materials of the new composite flotation agent to supercritical mixing and emulsification treatment. After the treatment, an emulsified oil-soluble composite coal preparation composite flotation agent can be obtained; the supercritical oxidation time is 15 minutes; the critical pressure during the preparation of the supercritical fluid is 22.1 MPa, and the critical temperature is 374°C.

[0028] The new composite coal flotation agent prepared in this example was naturally allowed to stand at room temperature for 48 hours, and was vibrated and shaken at certain intervals to observe whether the agent was stratified and evaluate its stability. The test results showed that the product of the present invention was still stable and not stratified after being allowed to stand at room temperature for 48 hours, and had good stability. Example

[0029] A composite coal flotation agent, the preparation raw materials of which are composed of the following components in parts by weight: 40 parts of oxidized kitchen waste grease, 20 parts of kerosene, 3 parts of oleic acid, 3 parts of sodium oleate, 4 parts of methyl octanoate, 5 parts of dodecyl polyoxyethylene ether and 25 parts of water.

[0030] The preparation method is the same as that of Example 1, except that the formula is changed to that of Example 2.

[0031] The composite coal flotation agents with good performance were prepared by using Examples 1-2, and the flotation test phenomena and effect comparison were carried out by using the composite coal flotation agents prepared by Examples 1-2 and the traditional non-polar hydrocarbon oil collectors to illustrate the good effect of Examples 1-5. The specific process is as follows:

[0032] Step 1: Add low-rank coal slurry (25% ash content) with a particle size of less than 0.5 mm into the flotation tank, add tap water to adjust the slurry, and stir for 1-2 minutes;

[0033] Step 2: Add collector (dosage 1.5 kg / t) to the slurry in step 1, stir for 2 min, then add frother and stir for 0.5 min;

[0034] Step 3: Bubbles are added to the ore pulp of step 2 for flotation. The flotation time is 3 min, and the flotation product is obtained and compared with the traditional non-polar hydrocarbon oil collector;

[0035] In step 3, when the dosage of the reagent is the same, it is observed that the new composite collector prepared by the present invention has better dispersibility in the ore pulp, faster flotation rate, stronger foam stability and easier dissipation, and the clean coal yield is improved to varying degrees compared with the traditional non-polar hydrocarbon oil collector.

[0036] The specific experimental data are as follows:

[0037] Example 1: The recovery rate of clean coal combustibles is 82%, and the clean coal ash content is 12.5%;

[0038] Example 2: The recovery rate of clean coal combustibles is 78%, and the clean coal ash content is 11.2%;

[0039] Traditional hydrocarbon oil reagents: The recovery rate of clean coal combustibles is 60%, and the clean coal ash content is 11.5%.

[0040] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for preparing a composite coal flotation agent made of oxidized kitchen waste oil. It is characterized in that The agent is composed of the following components in parts by weight: 30-40 parts of oxidized kitchen waste grease, 20-30 parts of kerosene, 3 parts of oleic acid, 3 parts of sodium oleate, 4 parts of methyl octanoate, 5 parts of dodecyl polyoxyethylene ether and 15-35 parts of water. The specific preparation method includes: (1) oxidizing the waste cooking oil by supercritical oxidation technology to obtain oxidized waste cooking oil; (2) Under magnetic stirring, add kerosene, oleic acid, sodium oleate, methyl octanoate, dodecyl polyoxyethylene ether and oxidized kitchen waste oil into the reaction container in order according to the proportion, and stir for 5 minutes; (3) The temperature and pressure of the reaction are increased, water is used as the supercritical reaction medium, water is prepared into a supercritical fluid under supercritical technology, and the composite flotation agent raw materials are subjected to supercritical mixed emulsification treatment. After the treatment is completed, an emulsified oil-soluble composite coal flotation agent can be obtained.

2. The method for preparing the composite coal flotation agent of oxidized kitchen waste oil as claimed in claim 1, It is characterized in that The agent is composed of the following components in parts by weight: 30 parts of oxidized kitchen waste grease, 30 parts of kerosene, 3 parts of oleic acid, 3 parts of sodium oleate, 4 parts of methyl octanoate, 5 parts of dodecyl polyoxyethylene ether and 25 parts of water.

3. The method for preparing the composite coal flotation agent of oxidized kitchen waste oil as claimed in claim 1, It is characterized in that The agent is composed of the following components in parts by weight: 40 parts of oxidized kitchen waste grease, 20 parts of kerosene, 3 parts of oleic acid, 3 parts of sodium oleate, 4 parts of methyl octanoate, 5 parts of dodecyl polyoxyethylene ether and 25 parts of water.

4. The method for preparing the composite coal flotation agent of oxidized kitchen waste oil as claimed in claim 1, It is characterized in that The supercritical oxidation time during oxidation in step (1) is 5-10 min.

5. The method for preparing the composite coal flotation agent of oxidized kitchen waste oil as claimed in claim 1, It is characterized in that The critical pressure during the preparation of the supercritical fluid in step (3) is 22.1 MPa and the critical temperature is 374 °C.

6. The method for preparing the composite coal flotation agent of oxidized kitchen waste oil as claimed in claim 1, It is characterized in that The time of supercritical mixing emulsification treatment in step (3) is 15 min.