A method for harmless regeneration treatment of waste rock wool

Abstract

The application discloses a harmless regeneration treatment method of waste rock wool, and is characterized by comprising the following steps: (1) mixing waste rock wool with waste alkali liquor, and performing reaction under stirring; (2) adding clay into the reaction product obtained in the step (1), and performing reaction under heating and stirring; (3) uniformly mixing the reaction product obtained in the step (2) with solid waste, and performing reaction under stirring, wherein the solid waste is at least one selected from the group consisting of furnace ash and gasification slag; and finally, building brick materials are obtained through reaction. The method realizes harmless regeneration treatment of waste rock wool in a waste treatment by waste mode through the synergistic treatment of waste rock wool and waste alkali liquor.

Description

Technical Field

[0001] This invention relates to the field of solid waste treatment technology, and in particular to a method for the harmless recycling of waste rock wool. Background Technology

[0002] Rock wool is a common building insulation material, belonging to the category of man-made mineral fiber materials, with a wide range of applications. However, the production and use of rock wool generate a large amount of rock wool waste (referred to as waste rock wool), such as waste cotton boards, waste cotton felts, waste pipe sleeves, and shredded cotton produced during production line cutting. Currently, the main methods for disposing of waste rock wool are landfill and incineration. However, both of these methods not only involve land occupation but also easily pollute the ecological environment. For example, landfill disposal leads to soil and water pollution, while incineration also pollutes the air and soil environment.

[0003] Waste alkali solution generally refers to the waste liquid containing a large amount of pollutants generated during petrochemical production processes, due to the use of alkali solutions to absorb H2S, wash oil products, and pyrolysis gases. Since alkali solutions are also commonly used in the production of fine chemicals, metal processing, and circuit board manufacturing, waste alkali solution is also unavoidably generated. Currently, waste alkali solution is produced in large quantities, has complex compositions, high COD, high pH, ​​and some has an irritating or foul odor. It also contains heavy metals and organic pollutants, posing a significant threat to the environment. Moreover, most industries' waste alkali solution also contains thiols, amines, phenols, and hydrogen sulfide, which are easily absorbed through the skin when the human body comes into contact with these pollutants, causing adverse effects on health. Therefore, properly treating waste alkali solution to ensure it meets discharge standards is of great importance. Currently, waste alkali solution treatment technologies are mainly divided into two categories: achieving discharge standards and reuse. The former mainly involves methods such as neutralization, precipitation, extraction, membrane separation, advanced oxidation, biological methods, and incineration, while the latter mainly involves alkali reuse, acid-base regeneration, and sodium salt recovery. However, due to its complex composition, the treatment of waste alkaline solution remains a challenge and a research hotspot in the field of industrial wastewater treatment. Summary of the Invention

[0004] The first objective of this invention is to provide a method for the harmless regeneration of waste rock wool, which co-processes waste rock wool and waste alkali solution to achieve the harmless regeneration of waste rock wool through a waste-to-waste approach.

[0005] The first objective of this invention is achieved through the following scheme.

[0006] A method for the harmless recycling of waste rock wool includes the following steps:

[0007] (1) Mix waste rock wool with waste alkali solution and react with stirring;

[0008] (2) Add clay to the reaction product obtained in step (1) and react under heating and stirring;

[0009] (3) The reaction product obtained in step (2) is mixed evenly with solid waste and reacted under stirring. The solid waste is selected from at least one of furnace ash and gasification slag. Finally, the reaction yields building brick material.

[0010] The waste alkaline solution described in this invention contains sulfides, and preferably uses waste alkaline solution generated during petrochemical production.

[0011] The clay is formed by the weathering of aluminosilicate minerals on the Earth's surface, and its main components are silicon oxide and aluminum oxide. This invention can use contaminated clay to further achieve the effect of resource utilization of contaminated clay.

[0012] The principle of this invention is as follows:

[0013] ①The main components of waste rock wool are silicon dioxide, ferric oxide and iron oxide. First, it is reacted with waste alkaline solution to produce framework-structured silicate minerals and metasilicic acid.

[0014] ②Since the waste alkaline solution contains inorganic and / or organic sulfides, such as hydrogen sulfide and mercaptans, adding clay in step (2) can react to generate sulfur-containing minerals such as pyrite or siderite, thereby solidifying the clay and fundamentally changing the occurrence form of the most difficult component to treat in the waste alkaline solution - sulfides.

[0015] ③ In step (3), furnace ash and / or gasification slag are used to react with sulfides in the waste alkaline solution to further reduce the activity of sulfides in the waste alkaline solution; at the same time, the furnace ash and gasification slag contain a large amount of amorphous aluminosilicates, which can be used to prepare building materials, and have the advantages of high temperature resistance, light weight and good thermal insulation performance, ensuring that the material obtained by the final reaction of this invention can be made into building bricks that meet the requirements.

[0016] This invention achieves the co-treatment of waste rock wool using waste alkaline solution through waste-to-waste treatment. The entire process generates zero waste (no new waste or waste liquid is produced) and zero landfill, realizing the harmless treatment of waste rock wool. Moreover, bricks made from the building brick material obtained by this invention meet the standard requirements of GB / T 5101-2017 "Ordinary Sintering Machines" and can be used in the construction industry, realizing the resource utilization of waste and waste liquid.

[0017] In step (1), the mass ratio of waste rock wool to waste alkali solution is 0.5-2:1-4, preferably 1:1.5.

[0018] In step (1), it is preferable to react for 2 to 2.5 hours with stirring.

[0019] In step (1), the waste rock wool is first dried and dehydrated, then crushed into granules, and then mixed with waste alkali solution for reaction.

[0020] In step (2), the ratio of the added clay mass to the total mass of waste rock wool and waste alkali solution is 1-2:1-1.5.

[0021] In step (2), the heating temperature is 150-180℃ and the reaction time is 0.5h.

[0022] In step (3), the ratio of the mass of added solid waste to the mass of the reaction product in step (2) is 1:0.8 to 1.5, that is, the ratio of the mass of added solid waste to the total mass of waste rock wool, waste alkali solution and clay is 1:0.8 to 1.5.

[0023] In step (3), the solid waste is selected from at least one of furnace ash and gasification slag. When the solid waste is a combination of furnace ash and gasification slag, there is no limitation on the mass ratio of the two, which can be 2:1, 1:1, 1:2, or 1:3. The reaction time in step (3) is preferably 2 hours.

[0024] Preferably, to simplify the entire recycling process, steps (2) and (3) can be carried out simultaneously. That is, clay and solid waste are added to the reaction product obtained in step (1), and the reaction is carried out under heating and stirring to obtain building brick material; wherein, the heating temperature is 150-180℃, and the reaction time is 2-2.5h. This invention confirms that carrying out steps (2) and (3) simultaneously can also achieve the purpose of this invention.

[0025] Furthermore, since the present invention does not require a reaction temperature in step (1), in order to optimize the process flow, the reaction device can be heated at the beginning of the regeneration process, that is, at the beginning of the reaction in step (1), so as to maintain the reaction temperature required in step (2) until the final reaction yields building brick material.

[0026] Furthermore, the present invention also includes step (4), which involves pressing and molding the building brick material obtained in step (3) and sintering it at high temperature to obtain sintered bricks. The pressing and molding and high-temperature sintering can be performed using conventional methods in the art.

[0027] Compared with the prior art, the present invention has the following beneficial effects.

[0028] This invention achieves ultra-low-cost treatment of waste rock wool through a waste-to-waste approach. Furthermore, it is a zero-waste, zero-landfill, and harmless recycling method, achieving cost reduction and efficiency improvement. Moreover, this invention can effectively treat waste alkaline solutions, furnace ash, and gasification slag, providing a new method for the recycling of these waste liquids and wastes.

[0029] This invention regenerates waste rock wool to obtain building brick materials, which not only reduces the harmfulness of waste but also realizes the resource utilization of waste. Detailed Implementation

[0030] The present invention will be further described below through specific embodiments.

[0031] Example 1

[0032] (1) After the collected waste rock wool is dried and dehydrated, it is crushed into granules by a crusher, placed in a ball mill, and the collected waste alkali solution is added. The mixture is heated to 150°C and stirred for 2 hours. The mass ratio of waste rock wool to alkali solution is 1:1.5. The waste alkali solution is generated during the petrochemical production process.

[0033] (2) After the reaction in step (1) is completed, clay and gasification slag are added and stirred at 150°C for 2.5 hours. The ratio of the mass of clay added to the total mass of waste rock wool and waste alkali is 1:1, and the ratio of the mass of gasification slag added to the mass of other raw materials is 1:1. Finally, the reaction yields building brick materials.

[0034] (3) Building bricks are obtained by pressing and high-temperature sintering.

[0035] The tested bricks meet the national standard GB / T 5101-2017 "Ordinary Sintering".

[0036] Example 2

[0037] (1) After the collected waste rock wool is dried and dehydrated, it is crushed into granules by a crusher, placed in a ball mill, and the collected waste alkali solution is added. The mixture is heated to 180°C and stirred for 2.5 hours. The mass ratio of waste rock wool to alkali solution is 1:1. The waste alkali solution is generated during the petrochemical production process.

[0038] (2) After the reaction in step (1) is completed, clay and furnace ash are added and stirred at 180°C for 2 hours; wherein, the mass ratio of clay added to the total mass of waste rock wool and waste alkali solution is 1:1.5, and the mass ratio of furnace ash added to the mass of other raw materials is 1:1; finally, the reaction yields building brick materials.

[0039] (3) Building bricks are obtained by pressing and high-temperature sintering.

[0040] The tested bricks meet the national standard GB / T 5101-2017 "Ordinary Sintering".

[0041] Example 3

[0042] (1) After the collected waste rock wool is dried and dehydrated, it is crushed into granules by a crusher, placed in a ball mill, and the collected waste alkali solution is added. The mixture is heated to 180°C and stirred for 2.5 hours. The mass ratio of waste rock wool to alkali solution is 1:1. The waste alkali solution is generated during the petrochemical production process.

[0043] (2) After the reaction in step (1) is completed, clay and furnace ash are added respectively, and the mixture is stirred at 180°C for 2.5 hours. The ratio of the mass of clay added to the total mass of waste rock wool and waste alkali is 1:1.5, and the ratio of the mass of gasification slag added to the mass of other raw materials is 1:1.5. Finally, the reaction yields building brick materials.

[0044] (3) Building bricks are obtained by pressing and high-temperature sintering.

[0045] The tested bricks meet the national standard GB / T 5101-2017 "Ordinary Sintering".

[0046] Example 4

[0047] (1) After the collected waste rock wool is dried and dehydrated, it is crushed into granules by a crusher, placed in a ball mill, and the collected waste alkali solution is added. The mixture is heated to 160°C and stirred for 2.5 hours. The mass ratio of waste rock wool to alkali solution is 1:2. The waste alkali solution is generated during the petrochemical production process.

[0048] (2) After the reaction in step (1) is completed, add clay, stir evenly, and stir and react at 160℃ for 0.5h; wherein, the mass ratio of clay added to the total mass of waste rock wool and waste alkali solution is 1:2.

[0049] (3) After the reaction in step (2) is completed, gasification slag and furnace ash are added and stirred for 2 hours; wherein, the total mass of gasification slag and furnace ash added is in the ratio of the mass of other raw materials to 1:0.8, and the mass ratio of gasification slag and furnace ash is 1:1; finally, the reaction yields building brick material.

[0050] (4) Building bricks are obtained by pressing and high-temperature sintering. The bricks are tested and found to conform to the national standard GB / T 5101-2017 "Ordinary Sintering".

[0051] Furthermore, the bricks prepared in Examples 1 to 4 above were tested. The chemical composition of the bricks showed that the mass percentage of SiO2 was between 60 and 70%, the mass percentage of Al2O3 was between 10 and 20%, the mass percentage of Fe2O3 was between 5 and 10%, the mass percentage of CaO was less than 8%, the mass percentage of MgO was less than 3%, and the mass percentage of SO3 (sulfur gangue) was less than 1%.

[0052] Meanwhile, the heavy metal content in the bricks produced was found to be below the corresponding control limits for heavy metals in the "Soil Environmental Quality Standard for Construction Land Soil Pollution Risk Control (Trial)" (GB36600-2018). In other words, the bricks produced by this invention pose no safety or environmental hazards and can be sold and used with confidence.

[0053] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be noted that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for the harmless recycling of waste rock wool, characterized in that, Includes the following steps: (1) The waste rock wool and waste alkali solution are mixed and reacted under stirring; the waste alkali solution contains sulfides; (2) Add clay to the reaction product obtained in step (1) and react under heating and stirring; (3) The reaction product obtained in step (2) is mixed evenly with solid waste and reacted under stirring. The solid waste is selected from at least one of furnace ash and gasification slag. Finally, the reaction yields building brick material.

2. The method for harmless regeneration of waste rock wool according to claim 1, characterized in that, Simultaneously, the reactions in steps (2) and (3) are carried out, that is, clay and solid waste are added to the reaction product obtained in step (1), and the reaction is carried out under heating and stirring to obtain building brick material.

3. The method for harmless recycling of waste rock wool according to claim 1 or 2, characterized in that, The mass ratio of waste rock wool to waste alkali solution is 0.5~2:1~4.

4. The method for harmless recycling of waste rock wool according to claim 3, characterized in that, The ratio of the added clay mass to the total mass of waste rock wool and waste alkali solution is 1~2:1~1.

5.

5. The method for harmless recycling of waste rock wool according to claim 4, characterized in that, The ratio of the added solid waste mass to the total mass of waste rock wool, waste alkali solution and clay is 1:0.8~1.

5.

6. The method for harmless recycling of waste rock wool according to claim 5, characterized in that, in The heating temperature in step (2) is 150~180℃; when the reactions in steps (2) and (3) are carried out simultaneously, the heating temperature is also 150~180℃.

7. The method for harmless recycling of waste rock wool according to claim 6, characterized in that, The reaction time for step (1) is 2~2.5h, the reaction time for step (2) is 0.5h, and the reaction time for step (3) is 2h; when steps (2) and (3) are carried out simultaneously, the reaction time is 2~2.5h.

8. The method for harmless recycling of waste rock wool according to claim 7, characterized in that, It also includes step (4), which involves pressing the building brick material obtained in step (3) into shape and sintering it at high temperature to obtain sintered bricks.