Waste spinning alternative fuel treatment and chloride ion detection method for cement production

Abstract

The invention provides a waste spinning alternative fuel treatment and chloride ion detection method for cement production, and belongs to the technical field of alternative fuels. The method comprises the following steps: crushing waste spinning, mixing the crushed waste spinning with zinc oxide and alkali in water at 35-50 DEG C, filtering, and drying to obtain the waste spinning alternative fuel for cement production. The waste spinning is treated in a reasonable mode, the heat value of the waste spinning can be kept unchanged, meanwhile, the chlorine ion content of the waste spinning can be greatly reduced, and control over alternative fuel chlorine ions is achieved; when the treated waste spinning alternative fuel is used for cement production, the content of chloride ions in clinker can be kept within a controllable range. Besides, according to the chloride ion detection method provided by the invention, the content of chloride ions is detected by utilizing existing detection equipment and conventional drugs, additional equipment does not need to be purchased, the use of dangerous chemicals such as potassium thiocyanate and ammonium ferric sulfate is reduced, the operation is simple and convenient, and the cost and space are saved.

Description

Technical Field

[0001] The invention relates to the technical field of alternative fuels, and in particular to a method for processing alternative fuels of waste textiles used in cement production and a method for detecting chloride ions. Background Art

[0002] With the improvement of people's living standards and the change of consumption concepts, the speed of textile renewal has accelerated and the amount of waste textiles generated has increased.

[0003] Compared with coal powder, waste textile has high volatile matter, low ash content, low moisture content, and considerable calorific value, and has good potential as an alternative fuel. Recycling waste textile as an alternative fuel can not only reduce its burden on the environment, realize the effective reuse of resources, and reduce resource waste, but also alleviate the shortage of domestic coal resources to a certain extent. However, when waste textile is burned, it will produce harmful substances such as Cl and S; in particular, the national standard chloride ion limit for cement is 0.06%, and the chlorine content in waste textile is between 0.2-0.6%. If it is not controlled, the use of a large amount of waste textile as an alternative fuel will cause the chloride ion of the clinker to exceed the standard, and the kiln will also have the risk of ring formation. Therefore, the present invention aims to provide a treatment method for treating waste textile so that when it is used as an alternative fuel, the generation and emission of toxic substances such as Cl and S are reduced. Summary of the invention

[0004] In view of the above deficiencies in the prior art, the present invention provides a method for treating waste textiles as an alternative fuel for cement production and detecting chloride ions, which pretreats the waste textiles in a reasonable manner to effectively reduce the chloride ion content thereof.

[0005] To achieve the above purpose, the specific technical solutions of the present invention are as follows:

[0006] In a first aspect, the present invention provides a method for treating waste textile alternative fuel for cement production, wherein the waste textile is crushed and mixed with zinc oxide and alkali in water at 35-50°C, filtered, and dried to obtain waste textile alternative fuel for cement production.

[0007] In view of the prior art, directly burning waste textiles as alternative fuels will cause excessive chloride ion content in clinker. The present invention adopts a reasonable method to pretreat the waste textiles, which can significantly reduce the chloride ion content in the waste textiles while maintaining its calorific value, so as to increase its usage in cement production, reduce production costs, achieve effective recycling of resources, and reduce resource waste.

[0008] Furthermore, the mass ratio of the waste textile, zinc oxide and alkali is 1000:(1-5):(10-30).

[0009] Furthermore, the mass volume ratio of the waste textile to water is 1: (3-10) g / mL.

[0010] Furthermore, the base is potassium hydroxide or sodium hydroxide.

[0011] Furthermore, the mixing time is 2 to 5 h.

[0012] Furthermore, the size of the shredded waste spinning is less than 20 mm.

[0013] Furthermore, the waste textiles include at least one of old clothing, bedding, curtains and carpets.

[0014] In a second aspect, the present invention provides a waste textile alternative fuel obtained by treating with the method.

[0015] In a third aspect, the present invention provides the use of the waste textile alternative fuel in cement production.

[0016] In a fourth aspect, the present invention provides a method for detecting chloride ions in the waste textile alternative fuel, comprising the following steps:

[0017] (1) Weighing a waste textile alternative fuel sample and an aliphatic mixture in a crucible and mixing them evenly to obtain a mixture, then covering the mixture with a certain mass of the aliphatic mixture and performing a burning treatment;

[0018] (2) Transfer the calcined product into a beaker, rinse the inner wall of the crucible with hot water, and pour the rinse liquid into the beaker;

[0019] (3) Filter the mixed solution obtained in step (2), rinse the residue with hot water 1 to 2 times, then transfer the residue into a funnel, and then carefully rinse the filter paper and the residue with hot water until there is no turbidity when tested with a silver nitrate solution;

[0020] (4) Take the liquid in step (3), place it in a beaker, and detect the chloride ion content using automatic potentiometric titration.

[0021] Furthermore, in the mixture, the mass ratio of the waste textile alternative fuel sample to the abrasive mixing agent is 1:4.

[0022] Furthermore, the calcination temperature is 660-700°C and the calcination time is 2-4 h.

[0023] The method for detecting chloride ions in the waste textile alternative fuel is as follows:

[0024] (1) Weigh 1 g of the waste textile alternative fuel sample and 4 g of the axelrod mixture in a crucible and mix them evenly to obtain a mixture. Then cover the mixture with 3 g of the axelrod mixture and calcine it at 660-700 °C for 2-4 h.

[0025] (2) Transfer the calcined product into a 250 mL beaker, rinse the inner wall of the crucible with 50-60 mL of hot water, and pour the rinse into the beaker;

[0026] (3) Filter with qualitative filter paper using the pouring method, rinse the residue with hot water 1 to 2 times, then transfer the residue into a funnel, and then carefully rinse the filter paper and residue with hot water until there is no turbidity when tested with silver nitrate solution; during the filtering and rinsing process, control the volume of the filtrate to 110 mL, and after cooling, adjust the volume to 250 mL and mix well;

[0027] (4) Take the liquid in step (3) (less than 50 mL), place it in a 250 mL dry beaker, and use automatic potentiometric titration to detect the chloride ion content.

[0028] Compared with the prior art, the present invention is beneficial in that:

[0029] (1) The present invention uses a reasonable method to process waste textiles to achieve control of chloride ions in alternative fuels, ensuring that when the waste textiles are used in cement production, the chloride ion content of clinker is within a controllable range; at the same time, it can also increase the use of waste textile alternative fuels in cement production and reduce production costs.

[0030] (2) The chloride ion detection method provided by the present invention utilizes existing detection equipment and conventional drugs to detect the chloride ion content, without the need to purchase additional equipment, thereby reducing the use of hazardous chemicals such as potassium thiocyanate and ammonium ferric sulfate. The method is easy to operate and saves costs and space. DETAILED DESCRIPTION

[0031] The technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. 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.

[0032] The invention provides a method for treating waste textile alternative fuel for cement production, comprising crushing the waste textile, mixing it with zinc oxide and alkali in water at 35-50°C, filtering and drying to obtain the waste textile alternative fuel for cement production.

[0033] In some examples, the mass ratio of the waste textile, zinc oxide, and alkali is 1000:(1-5):(10-30).

[0034] In some examples, the mass volume ratio of the waste textile to water is 1:(3-10) g / mL; in the following specific embodiments, the mass volume ratio of the waste textile to water is 1:5 g / mL.

[0035] In some examples, the base is potassium hydroxide or sodium hydroxide.

[0036] In some examples, the mixing time is 2 to 5 hours.

[0037] In some examples, the size of the shredded waste is less than 20 mm.

[0038] In some examples, the waste textiles include at least one of old clothing, bedding, curtains, and carpets.

[0039] The method for detecting chloride ions in the waste textile alternative fuel is as follows:

[0040] (1) Weigh 1 g of the waste textile alternative fuel sample and 4 g of the axelrod mixture in a crucible and mix them evenly to obtain a mixture. Then cover the mixture with 3 g of the axelrod mixture and calcine it at 660-700 °C for 2-4 h.

[0041] (2) Transfer the calcined product into a 250 mL beaker, rinse the inner wall of the crucible with 50-60 mL of hot water, and pour the rinse into the beaker;

[0042] (3) Filter with qualitative filter paper using the pouring method, rinse the residue with hot water 1 to 2 times, then transfer the residue into a funnel, and then carefully rinse the filter paper and residue with hot water until there is no turbidity when tested with silver nitrate solution; during the filtering and rinsing process, control the volume of the filtrate to 110 mL, and after cooling, adjust the volume to 250 mL and mix well;

[0043] (4) Take less than 50 mL of the liquid in step (3) and place it in a 250 mL dry beaker. Use automatic potentiometric titration to detect the chloride ion content.

[0044] Example 1

[0045] A cement production waste textile (waste carpet) alternative fuel

[0046] The waste textile is crushed into a size less than 20 mm, mixed with zinc oxide and sodium hydroxide in water at 40°C for 3 hours, filtered and dried to obtain waste textile alternative fuel for cement production; wherein the mass ratio of the waste textile, zinc oxide and sodium hydroxide is 1000:5:10.

[0047] Detection of chloride ion content in waste textiles before and after treatment:

[0048] (1) Weigh 1 g of the waste textile sample before and after treatment and mix them with 4 g of the axelrod mixture in a crucible to obtain a mixture, then cover the mixture with 3 g of the axelrod mixture and calcine at 680 °C for 3 h;

[0049] (2) Transfer the calcined product into a 250 mL beaker, rinse the inner wall of the crucible with 50 mL of hot water, and pour the rinse into the beaker;

[0050] (3) Filter with qualitative filter paper using the pouring method, rinse the residue twice with hot water, then transfer the residue into a funnel, and then carefully rinse the filter paper and residue with hot water until there is no turbidity when tested with silver nitrate solution; during the filtering and rinsing process, control the volume of the filtrate to 110 mL, cool it down, make up to 250 mL, and mix well;

[0051] (4) Take 50 mL of the liquid in step (3) and place it in a 250 mL dry beaker. Use automatic potentiometric titration to detect the chloride ion content. The results are shown in Table 1.

[0052] Example 2

[0053] A cement production using waste textiles (old clothes and curtains) as a fuel alternative

[0054] The waste textile is crushed into a size less than 20 mm, mixed with zinc oxide and sodium hydroxide in water at 40°C for 3 hours, filtered and dried to obtain waste textile alternative fuel for cement production; wherein the mass ratio of the waste textile, zinc oxide and sodium hydroxide is 1000:1:30.

[0055] Detection of chloride ion content in waste textiles before and after treatment:

[0056] (1) Weigh 1 g of the waste textile sample before and after treatment and mix them with 4 g of the axelrod mixture in a crucible to obtain a mixture, then cover the mixture with 3 g of the axelrod mixture and calcine at 680 °C for 3 h;

[0057] (2) Transfer the calcined product into a 250 mL beaker, rinse the inner wall of the crucible with 50 mL of hot water, and pour the rinse into the beaker;

[0058] (3) Filter with qualitative filter paper using the pouring method, rinse the residue twice with hot water, then transfer the residue into a funnel, and then carefully rinse the filter paper and residue with hot water until there is no turbidity when tested with silver nitrate solution; during the filtering and rinsing process, control the volume of the filtrate to 110 mL, cool it down, make up to 250 mL, and mix well;

[0059] (4) Take 50 mL of the liquid in step (3) and place it in a 250 mL dry beaker. Use automatic potentiometric titration to detect the chloride ion content. The results are shown in Table 1.

[0060] Comparative Example 1

[0061] A cement production waste textile (waste carpet) alternative fuel

[0062] The waste textile is crushed into a size less than 20 mm, mixed with sodium hydroxide in water at 40°C for 3 hours, filtered, and dried to obtain a waste textile alternative fuel for cement production; wherein the mass ratio of the waste textile to sodium hydroxide is 1000:15.

[0063] The method in Example 1 was used to detect the chloride ion content in the treated waste textiles. The results are shown in Table 1.

[0064] Comparative Example 2

[0065] A cement production waste textile (waste carpet) alternative fuel

[0066] The waste textile is crushed into a size less than 20 mm, mixed with zinc oxide and sodium hydroxide in water at 40°C for 3 hours, filtered and dried to obtain waste textile alternative fuel for cement production; wherein the mass ratio of the waste textile, zinc oxide and sodium hydroxide is 1000:0.5:14.5.

[0067] The method in Example 1 was used to detect the chloride ion content in the treated waste textiles. The results are shown in Table 1.

[0068] Comparative Example 3

[0069] A cement production waste textile (waste carpet) alternative fuel

[0070] The waste textile is crushed into a size less than 20 mm, mixed with zinc oxide and sodium hydroxide in water at 40°C for 3 hours, filtered and dried to obtain waste textile alternative fuel for cement production; wherein the mass ratio of the waste textile, zinc oxide and sodium hydroxide is 1000:6:9.

[0071] The method in Example 1 was used to detect the chloride ion content in the treated waste textiles. The results are shown in Table 1.

[0072] Table 1: Calorific value and chloride ion content of waste textiles before and after treatment

[0073]

[0074] As can be seen from Table 1, the present invention uses a reasonable method to treat waste textiles, which can significantly reduce its chloride ion content while maintaining its calorific value unchanged; using the treated waste textiles as an alternative fuel for cement production can ensure that the chloride ion content of the clinker is within a controllable range; and at the same time, it can also increase the use of waste textile alternative fuel in cement production to reduce costs. In the process of treating waste textiles, if alkali is used to completely replace zinc oxide (Comparative Example 1), or alkali is used to partially replace zinc oxide (Comparative Example 2), or zinc oxide is used to partially replace alkali (Comparative Example 3), the chloride ion content in the waste textile alternative fuel obtained after treatment is still relatively high.

[0075] The above specific embodiments describe the implementation of the present invention in detail, but the present invention is not limited to the specific details in the above embodiments. Within the scope of the claims and technical concept of the present invention, the technical solution of the present invention can be modified and changed in many simple ways, and these simple modifications all belong to the protection scope of the present invention.

Claims

1. A method for treating waste textiles as an alternative fuel for cement production, characterized in that: The waste textile is crushed and mixed with zinc oxide and alkali in water at 35-50°C, filtered and dried to obtain the waste textile alternative fuel for cement production.

2. A method for treating waste textiles as an alternative fuel for cement production according to claim 1, characterized in that: The mass ratio of the waste textile, zinc oxide and alkali is 1000:(1-5):(10-30).

3. The method for treating waste textile as an alternative fuel for cement production according to claim 1, characterized in that: The alkali is potassium hydroxide or sodium hydroxide.

4. The method for treating waste textile as an alternative fuel for cement production according to claim 1, characterized in that: The mixing time is 2 to 5 h.

5. The method for treating waste textile as an alternative fuel for cement production according to claim 1, characterized in that: The size of the shredded waste is less than 20 mm.

6. The waste textile alternative fuel obtained by the method according to any one of claims 1 to 5.

7. Use of the waste textile alternative fuel as claimed in claim 6 in cement production.

8. A method for detecting chloride ions in waste textile alternative fuels as claimed in claim 6, characterized in that: The following steps are involved: (1) Weighing a waste textile alternative fuel sample and an aliphatic mixture in a crucible and mixing them evenly to obtain a mixture, then covering the mixture with a certain mass of the aliphatic mixture and performing a burning treatment; (2) Transfer the calcined product into a beaker, rinse the inner wall of the crucible with hot water, and pour the rinse liquid into the beaker; (3) filtering the mixed solution obtained in step (2), washing the residue with hot water for 1 to 2 times, then transferring the residue into a funnel, and then washing the filter paper and the residue with hot water until there is no turbidity when tested with a silver nitrate solution; (4) Take the liquid in step (3), place it in a beaker, and detect the chloride ion content using automatic potentiometric titration.

9. The method for detecting chloride ions in waste textile alternative fuel according to claim 8, characterized in that: The burning temperature is 660-700°C and the burning time is 2-4 hours.

10. The method for detecting chloride ions in waste textile alternative fuel according to claim 8, characterized in that: The details are as follows: (1) Weigh 1 g of the waste textile alternative fuel sample and 4 g of the axelrod mixture in a crucible, mix them evenly, then cover them with 3 g of the axelrod mixture, and calcine them at 660-700 °C for 2-4 h; (2) Transfer the calcined product into a 250 mL beaker, rinse the inner wall of the crucible with 50-60 mL of hot water, and pour the rinse into the beaker; (3) Filter with qualitative filter paper using the pouring method, rinse the residue with hot water 1 to 2 times, then transfer the residue into a funnel, and then carefully rinse the filter paper and residue with hot water until there is no turbidity when tested with silver nitrate solution; during the filtering and rinsing process, control the volume of the filtrate to 110 mL, and after cooling, adjust the volume to 250 mL and mix well; (4) Take 50 mL of the liquid in step (3), place it in a 250 mL dry beaker, and use automatic potentiometric titration to detect the chloride ion content.

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