Glass fiber reinforced plastic waste and sludge co-processing and resource utilization method

Abstract

The invention relates to the technical field of resource utilization, and discloses a glass fiber reinforced plastic waste and sludge co-processing and resource utilization method which comprises the following steps: crushing glass fiber reinforced plastic waste, performing alkali liquor treatment, washing, drying and re-crushing to prepare glass fiber reinforced plastic aggregate with the particle size of 0.3-4mm; mixing the dewatered sludge with quick lime, and carrying out curing treatment to obtain sludge clinker; and uniformly mixing the glass fiber reinforced plastic aggregate, the concrete recycled aggregate, the sludge clinker, cement, fly ash and an alkali activator, and carrying out compression molding and maintenance to obtain the baking-free brick. According to the method, the glass fiber reinforced plastic waste and the sludge are subjected to specific chemical pretreatment, so that the problems that the interfacial compatibility of the glass fiber reinforced plastic and an inorganic cementing material is poor, and direct utilization of the sludge can inhibit hardening of the cementing material and has environmental risks are solved. The method realizes efficient co-processing of two bulk solid wastes, and the prepared baking-free brick has excellent mechanical properties, does not need high-temperature sintering in the whole process, and has the advantages of low energy consumption, controllable cost and environmental friendliness.

Description

Technical Field

[0001] This invention relates to the field of resource utilization technology, specifically to a method for the co-processing and resource utilization of fiberglass waste and sludge. Background Technology

[0002] With the acceleration of my country's industrialization and urbanization, the amount of solid waste generated is increasing daily, and its disposal and resource utilization have become key issues restricting the sustainable development of society and economy and the construction of ecological civilization. Among the many types of solid waste, waste fiberglass (also known as fiber-reinforced plastic, FRP) and municipal sludge are two typical examples that are widely sourced, difficult to dispose of, and have significant environmental impacts.

[0003] Fiberglass reinforced plastic (FRP) is widely used in construction, transportation, chemical, and aerospace industries due to its excellent properties such as lightweight, high strength, and corrosion resistance. However, FRP is a thermosetting composite material, and its matrix resin cannot be remelted and reshaped after cross-linking and curing, making the recycling and disposal of its waste (including production scraps and discarded products) extremely difficult. Currently, the mainstream disposal methods for FRP waste include landfill and incineration. Landfilling not only occupies a large amount of valuable land resources, but FRP is also extremely difficult to degrade under natural conditions, causing long-term potential pollution to soil and groundwater. While incineration can reduce volume and recover some heat energy, its resin components may produce harmful gases such as dioxins during incomplete combustion, causing secondary air pollution. Additionally, the glass fibers may melt and clump at high temperatures, damaging incinerator equipment. Physical recycling, which involves crushing FRP waste into powder or short fibers as filler, is one of the more promising resource recovery methods. However, in the existing technology, the fiberglass powder obtained by direct crushing has a surface coated with hydrophobic resin, which has poor compatibility with inorganic cementitious materials such as cement and low interfacial bonding strength. This limits its dosage in concrete or mortar, and the mechanical properties of the final product often deteriorate, making it difficult to achieve high-value utilization.

[0004] On the other hand, municipal sludge is an inevitable byproduct of urban wastewater treatment, with its output being enormous and increasing year by year. Statistics show that in 2021, my country's annual municipal sludge production reached tens of millions of tons. Sludge has a complex composition, rich in organic matter and nutrients such as nitrogen and phosphorus, but also contaminated with heavy metals, persistent organic pollutants, and pathogenic microorganisms. Improper disposal can easily pose a serious threat to the ecological environment and public health. Currently, sludge disposal methods mainly include landfilling, incineration, land application, and building material utilization. Similar to fiberglass, sludge landfilling and incineration also present problems such as land occupation, secondary pollution, and high energy consumption. Land application is limited by the pollutant content in the sludge, with extremely strict application scope and standard requirements. Using sludge to fire ceramsite or bricks is a resource utilization path, but traditional firing processes generally suffer from high energy consumption, long production cycles, and complex problems such as heavy metal volatilization at high temperatures and flue gas treatment, which contradict the direction of green and low-carbon development.

[0005] In summary, existing technologies for the disposal of fiberglass waste and municipal sludge mostly employ single-path treatment, generally suffering from drawbacks such as high disposal costs, high energy consumption, potential secondary pollution, or low added value of resource-based products. Currently, there is a lack of an effective method for the efficient co-processing of these two bulk solid wastes with vastly different properties, and for their resource-based preparation into high-performance products that meet standards in a low-energy-consumption and environmentally friendly manner. Therefore, developing a new technology that enables the "waste-to-waste" co-processing and resource-based utilization of fiberglass waste and sludge has significant practical implications and broad application prospects. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a method for the co-processing and resource utilization of fiberglass waste and sludge. This method solves the problems in existing technologies, such as poor interfacial compatibility between fiberglass waste and inorganic materials leading to low performance of resource-based products, and the difficulty in using sludge directly to inhibit the hardening of cementitious materials and pose environmental risks, thus making it difficult to use both in combination to prepare high-performance non-fired building materials.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for the co-processing and resource utilization of fiberglass waste and sludge, comprising:

[0008] a. Pre-treat fiberglass waste to obtain fiberglass aggregate;

[0009] b. Pre-treat the sludge to obtain a cementitious material containing sludge clinker;

[0010] c. The fiberglass aggregate is mixed with the cementitious material, and then pressed and cured to obtain non-fired bricks.

[0011] Preferably, the step of pre-treating the fiberglass waste in step a specifically includes: crushing the fiberglass waste and then treating it with an alkaline solution to remove some of the resin on the surface of the fiberglass and modify its surface.

[0012] Preferably, the alkaline treatment conditions are as follows: the alkaline solution is a NaOH or KOH solution with a concentration of 5%-18%, the liquid-to-solid ratio is 8:1-15:1, and the reaction temperature is 40℃-90℃.

[0013] Preferably, the pretreatment step of fiberglass waste further includes:

[0014] The material treated with alkali solution is subjected to solid-liquid separation, washing and drying, followed by deep crushing and screening to obtain the fiberglass aggregate with a particle size of 0.3mm-4mm.

[0015] Preferably, the step of pretreating the sludge in step b specifically involves mixing dewatered sludge with lime for slaking treatment to obtain the sludge clinker.

[0016] Preferably, the cementing material is a mixture of the sludge clinker, cement, and fly ash in a preset ratio.

[0017] Preferably, the fiberglass aggregate is mixed with recycled coarse aggregate and recycled fine aggregate for concrete, and then mixed with the cementitious material as a composite aggregate.

[0018] Preferably, in step c, when mixing the fiberglass aggregate with the cementitious material, an alkali activator is also added to activate the cementitious material.

[0019] Preferably, the alkaline activator is a mixture of NaOH and Na2SiO3.

[0020] Preferably, the unfired bricks produced contain the following components by mass percentage: 9.8%-11.6% fiberglass aggregate, 29.4%-34.8% recycled coarse aggregate for concrete, 19.6%-23.2% recycled fine aggregate for concrete, 4-5.5% dewatered sludge, 16-22% cement, and 8-11% fly ash.

[0021] This invention provides a method for the co-processing and resource utilization of fiberglass waste and sludge. It has the following beneficial effects:

[0022] 1. This invention successfully integrates two different types of solid waste into the same product system by using pre-treated fiberglass waste as aggregate and municipal sludge as a component of cementitious material after aging treatment. This provides an effective resource utilization pathway for fiberglass waste and municipal sludge, reducing the risk of environmental pollution.

[0023] 2. This invention uses alkaline solution to pretreat fiberglass waste, which removes some of the resin from its surface and increases surface roughness, thereby improving the interfacial bonding performance between the fiberglass aggregate and the cementitious material. Simultaneously, the alkaline activator activates the sludge clinker and fly ash, contributing to the formation of a stronger cementitious structure. Therefore, the prepared unfired bricks can achieve a compressive strength of up to 15 MPa, and the product performance is stable and reliable.

[0024] 3. This invention employs a non-firing process, which, compared to traditional sintering processes, eliminates the need for high-temperature calcination, significantly reducing energy consumption and carbon dioxide emissions during production. Furthermore, this invention extensively utilizes solid waste such as fiberglass waste, municipal sludge, recycled aggregates, and fly ash, replacing natural sand and gravel and some cement, thus conserving primary mineral resources and reducing production costs. Attached Figure Description

[0025] Figure 1 This is a process flow diagram for preparing fiberglass fines from fiberglass waste according to the present invention;

[0026] Figure 2 This is a flow chart of the co-processing technology for fiberglass fines and sludge of the present invention. Detailed Implementation

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Please see the appendix Figure 1 - Appendix Figure 2 This invention provides a method for the co-processing and resource utilization of fiberglass waste and sludge, comprising:

[0029] Two types of solid waste with different sources and properties, namely fiberglass waste and urban dewatered sludge, are transformed into aggregate components and cementitious material components required for the preparation of non-fired bricks through a series of targeted pretreatment steps. Then, through optimized proportioning design, mixing, molding and curing, environmentally friendly non-fired bricks that meet the requirements of building use are finally produced, realizing the efficient synergistic treatment and resource utilization of two bulk solid wastes.

[0030] Reference Figure 1 The pretreatment process of fiberglass waste in this invention, namely step a of preparing fiberglass aggregate, is as follows: First, the collected waste fiberglass products or production scraps are initially crushed by equipment such as jaw crusher or hammer crusher to obtain fiberglass fragments with a particle size of 1cm to 2cm.

[0031] Subsequently, the fiberglass scraps were placed in a reactor equipped with a stirrer for alkaline treatment. The purpose of this step is to hydrolyze and remove some of the cured resin coating the fiberglass surface using a strong alkaline environment, while simultaneously etching the exposed fiberglass surface to increase its surface roughness and the number of hydrophilic hydroxyl groups, thereby enhancing its interfacial adhesion to inorganic cementitious materials. The alkaline solution used is either sodium hydroxide (NaOH) or potassium hydroxide (KOH) solution, with a mass concentration controlled between 5% and 18%. The liquid-to-solid ratio (by mass) of the alkaline solution to the fiberglass scraps is 8:1 to 15:1. The reaction is carried out at a temperature of 40°C to 90°C for 1 to 6 hours, maintaining a stirring intensity sufficient to uniformly suspend the solid particles in the liquid phase. By controlling these conditions, a resin removal rate of 10% to 30% can be achieved.

[0032] After the alkaline treatment, the slurry in the reactor is separated using solid-liquid separation equipment such as a plate and frame filter press to obtain recyclable alkaline solution and filter residue. The resulting filter residue is washed using a three-stage countercurrent washing process at room temperature to remove residual alkaline solution and dissolved organic matter. The washing liquid from the third-stage washing process is used to prepare the new alkaline solution, while the pH value of the washing liquid discharged from the first-stage washing process is controlled to be less than or equal to 7 to ensure the neutrality of the filter residue. The washed filter residue is then sent to an oven or drying kiln and dried at 60℃ to 90℃ for 3 to 6 hours until its residual moisture content is less than or equal to 5%, yielding pretreated fiberglass coarse material.

[0033] The dried fiberglass coarse material is deeply crushed using equipment such as a ball mill or impact crusher, and then classified by a screening system to obtain fine fiberglass material with a particle size distribution in the range of 0.3 mm to 4 mm. This fine fiberglass material is used as an aggregate component in this invention.

[0034] To optimize the aggregate gradation of the final product and improve the density and mechanical properties of the unfired bricks, this invention combines the aforementioned fiberglass fine aggregate with recycled coarse aggregate and recycled fine aggregate for concrete. The recycled coarse aggregate for concrete has a particle size of 5mm to 10mm, and the recycled fine aggregate for concrete has a particle size of 0.3mm to 5mm. The three are mixed in a mass ratio of 1:3:2 to obtain the composite aggregate for preparing unfired bricks.

[0035] The sludge pretreatment process in this invention, specifically step b, of preparing a cementitious material containing sludge clinker, is as follows: Urban dewatered sludge with a moisture content of 60% or less is mechanically stirred with quicklime in a mixer. The amount of quicklime added is 5% to 10% of the mass of the dewatered sludge. The mixed material is then hydrated at 50°C to 70°C for 1 to 3 hours. This process utilizes the high temperature and strongly alkaline environment generated by lime digestion to achieve sterilization and disinfection of the sludge, degradation of some organic matter, and preliminary stabilization of heavy metals, resulting in sludge clinker.

[0036] The obtained sludge clinker, P.O42.5 ordinary Portland cement, and Grade I or II fly ash were mixed as components of the cementitious material. The three were uniformly mixed at a mass ratio of 0.5:2:1 to obtain a composite cementitious material. In this system, cement serves as the main hydration and hardening material, fly ash provides pozzolanic activity, and sludge clinker serves as a resource-based filler and part of the active component.

[0037] In step c of preparing the non-fired bricks, to further activate the potential activity of components such as fly ash in the composite cementitious material, this invention introduces an alkali activator. This alkali activator is composed of an aqueous solution of sodium hydroxide (NaOH) and sodium silicate (Na2SiO3), wherein the mass ratio of sodium hydroxide to sodium silicate is 1:1 to 1:1.5. The amount of alkali activator added is determined according to the mass of the composite cementitious material, and the relationship is shown in the following formula:

[0038] ;

[0039] in, The mass of the added alkaline activator;

[0040] The total mass of the composite cementitious materials used;

[0041] The activator dosage coefficient ranges from 10% to 18%.

[0042] The final preparation process of the non-fired bricks is as follows: The aforementioned composite aggregate, composite cementitious material, and alkali activator calculated according to the above formula are placed together in a forced mixer for thorough and uniform mixing. The uniformly mixed material is then fed into a non-fired brick press and pressed into standard-sized brick blanks under a preset pressure. The formed brick blanks are then placed in a standard curing room and cured for 28 days at a temperature of 20±2℃ and a relative humidity of not less than 95%. After the curing period, finished non-fired bricks with qualified performance indicators are obtained, and their 28-day compressive strength can reach more than 15MPa. By precisely controlling the proportions of each raw material, the final unfired bricks contain the following original components by mass percentage: 9.8%-11.6% fiberglass aggregate, 29.4%-34.8% recycled coarse aggregate for concrete, 19.6%-23.2% recycled fine aggregate for concrete, 4-5.5% dewatered sludge, 16-22% cement, and 8-11% fly ash.

[0043] Example 1

[0044] Raw material pretreatment: Take 12.5 kg of waste fiberglass scraps, crush them initially, and react them with 125 kg of 10% NaOH solution at 80℃ for 2 hours. After separation, washing, and drying, 11 kg of fine fiberglass material with a particle size of 0.3 mm-4 mm is obtained. Separately, take 10 kg of dewatered sludge with a moisture content of 60% (4 kg dry weight), add 0.8 kg of quicklime (8% wet weight), and slake it at 60℃ for 2 hours.

[0045] Raw material preparation: Mix 11 kg of fiberglass fine aggregate, 33 kg of recycled coarse aggregate for concrete, and 22 kg of recycled fine aggregate for concrete to obtain 66 kg of composite aggregate. Mix hydrated sludge (4.8 kg dry basis) with 16 kg of cement and 8 kg of fly ash to obtain 28.8 kg of composite cementitious material.

[0046] Preparation: Prepare an alkali activator with a NaOH to Na2SiO3 mass ratio of 1:1.2. Use 15% (4.32 kg) of the composite cementitious material as the activator dosage. Mix the composite aggregate, composite cementitious material, and alkali activator evenly, press into shape, and cure for 28 days according to standard.

[0047] Product Analysis: Calculations show that the mass percentages of the solid components (approximately 94.8 kg dry basis) in the finished unfired bricks are as follows: fiberglass aggregate 11.6%, recycled coarse aggregate 34.8%, recycled fine aggregate 23.2%, dewatered sludge (dry basis) 4.2%, cement 16.9%, and fly ash 8.4%. All components are within the range described in the claims. Testing showed that the 28-day average compressive strength of this batch of unfired bricks is 17.2 MPa.

[0048] Example 2

[0049] Raw material pretreatment: Take 12 kg of waste fiberglass scraps, crush them initially, and react them with 96 kg of 5% NaOH solution (liquid-solid ratio 8:1) at 40℃ for 6 hours. After treatment, 10 kg of fine fiberglass material with a particle size of 0.3 mm-4 mm is obtained. Separately, take 13.75 kg of dewatered sludge with a moisture content of 60% (dry weight 5.5 kg), add 0.69 kg of quicklime (5% wet weight), and slake it at 50℃ for 3 hours.

[0050] Raw material preparation: Mix 10kg of fiberglass fine aggregate, 30kg of recycled coarse aggregate for concrete, and 20kg of recycled fine aggregate for concrete to obtain 60kg of composite aggregate. Mix the matured sludge (6.19kg dry basis) with 22kg of cement and 11kg of fly ash to obtain 39.19kg of composite cementitious material.

[0051] Preparation: Prepare an alkaline activator, wherein the mass ratio of NaOH to Na2SiO3 is 1:1. Take 10% (3.92 kg) of the composite cementitious material as the activator dosage. Mix all materials evenly, press into shape, and cure for 28 days according to standard.

[0052] Product Analysis: Calculations show that the mass percentages of each solid component (approximately 99.19 kg dry basis) in the finished unfired bricks are as follows: fiberglass aggregate 10.1%, recycled coarse aggregate 30.2%, recycled fine aggregate 20.2%, dewatered sludge (dry basis) 5.5%, cement 22.2%, and fly ash 11.1%. All components are within or near the scope of the claims. Testing revealed that the 28-day average compressive strength of this batch of unfired bricks is 15.3 MPa.

[0053] Example 3

[0054] Raw material pretreatment: Take 15 kg of waste fiberglass scraps, crush them initially, and react them with 225 kg of 18% KOH solution (liquid-solid ratio 15:1) at 90℃ for 1 hour. After treatment, 11.5 kg of fine fiberglass material with a particle size of 0.3 mm-4 mm is obtained. Separately, take 10 kg of dewatered sludge with a moisture content of 60% (dry weight 4 kg), add 1.0 kg of quicklime (10% of wet weight), and slake it at 70℃ for 1 hour.

[0055] Raw material preparation: Mix 11.5 kg of fiberglass fine aggregate, 34.5 kg of recycled coarse aggregate for concrete, and 23 kg of recycled fine aggregate for concrete to obtain 69 kg of composite aggregate. Mix 5 kg of hydrated sludge (dry basis) with 16 kg of cement and 8 kg of fly ash to obtain 29 kg of composite cementitious material.

[0056] Preparation: Prepare an alkaline activator with a NaOH to Na2SiO3 mass ratio of 1:1.5. Use 18% (5.22 kg) of the composite cementitious material as the activator dosage. Mix all materials thoroughly, press into shape, and cure for 28 days according to standard conditions.

[0057] Product Analysis: Calculations show that the mass percentages of each solid component (approximately 98 kg dry basis) in the finished unfired bricks are as follows: fiberglass aggregate 11.7%, recycled coarse aggregate 35.2%, recycled fine aggregate 23.5%, dewatered sludge (dry basis) 4.1%, cement 16.3%, and fly ash 8.2%. All components are within or near the scope of the claims. Testing revealed that the 28-day average compressive strength of this batch of unfired bricks is 18.8 MPa.

[0058] Comparative example:

[0059] Raw material preparation and processing: (1) Take 12.5 kg of waste fiberglass scraps, the same as in Example 1, and physically crush and screen them to directly obtain 12.5 kg of fiberglass fines with a particle size of 0.3 mm-4 mm. This process does not involve any alkaline treatment. (2) Take 10 kg of dewatered sludge with a moisture content of 60% (dry weight 4 kg), the same as in Example 1, and use it directly as an admixture without any lime slaking treatment.

[0060] Raw material preparation:

[0061] (1) Mix 12.5 kg of untreated fiberglass fine aggregate, 33 kg of recycled coarse aggregate for concrete and 22 kg of recycled fine aggregate for concrete to obtain 67.5 kg of composite aggregate.

[0062] (2) Mix the uncured dewatered sludge (4 kg dry basis) with 24 kg cement. To maintain a similar total cementitious material content as in Example 1, no fly ash was added in this comparative example.

[0063] (3) No additional alkaline activator was added.

[0064] Preparation process: The above-mentioned composite aggregate, cement, and uncured dewatered sludge were placed in a mixer, and an appropriate amount of water was added for mixing until homogeneous. The mixture was then pressed into shape and cured for 28 days under the same standard conditions as in Example 1.

[0065] Test Example 1: Comparison Test of the Technical Effects of the Embodiments of the Invention and the Comparative Example

[0066] To verify the significant advancement of the present invention compared to methods without key pretreatment steps, the performance of the unfired brick samples prepared in Examples 1, 2, and 3 was compared with that of the unfired brick sample prepared in Comparative Example 1. The core indicator tested was the 28-day average compressive strength, while the appearance and water stability of the samples were also observed. The test results are summarized in Table 1.

[0067] Table 1 Comparison of data between embodiments of the present invention and comparative examples.

[0068] test group Fiberglass pretreatment sludge pretreatment 28-day average compressive strength (MPa) Appearance and stability Comparative Example 1 Physical crushing only, without alkali treatment. No lime slaking was performed 7.8 It has a loose surface, an unpleasant odor, and peels off at the edges after soaking in water. Example 1 Alkali treatment (10% NaOH, 80℃) Lime slaking (8% addition, 60℃) 17.2 The surface is dense, odorless, and the structure remains intact after soaking in water. Example 2 Alkali treatment (5% NaOH, 40℃) Lime slaking (5% addition, 50℃) 15.3 The surface is dense, odorless, and the structure remains intact after soaking in water. Example 3 Alkali treatment (18% KOH, 90℃) Lime slaking (10% addition, 70℃) 18.8 The surface is dense, odorless, and the structure remains intact after soaking in water.

[0069] As can be clearly seen from the data in Table 1, the 28-day compressive strength of the non-fired bricks prepared in Examples 1, 2, and 3 of this invention is significantly higher than that of Comparative Example 1, with the strength value being more than twice that of Comparative Example 1, and all exceeding the performance requirement of 15 MPa. Furthermore, the appearance quality and water stability of the example samples are also far superior to those of the comparative example samples.

[0070] This result strongly demonstrates the necessity and effectiveness of the key technical steps included in this invention. Specifically:

[0071] Alkali pretreatment of fiberglass effectively removes the hydrophobic resin layer on the surface of fiberglass and modifies its surface, greatly improving its interfacial compatibility and bonding strength with inorganic cementitious materials, transforming it from a structural defect into an effective aggregate component.

[0072] Lime slaking treatment of sludge: The sludge was effectively stabilized and rendered harmless, eliminating the negative impact of organic matter on the hydration reaction of cementitious materials, and endowing the sludge with a certain degree of activity, enabling it to participate as a beneficial component in the construction of the cementitious system.

[0073] Therefore, this test case fully demonstrates that the present invention can solve the problem of low performance caused by simple physical mixing in the prior art by performing specific synergistic pretreatment on two types of solid waste.

[0074] Test Example 2: Performance and Process Condition Comparison Test of Different Embodiments of the Invention

[0075] To determine the preferred range of process parameters in the technical solution of this invention, the results of Examples 1, 2, and 3 under different process parameters were compared and analyzed. The comparison aims to evaluate the comprehensive impact of different parameter combinations on the final product performance and process economy. The comparison results are summarized in Table 2.

[0076] Table 2 Comparison of performance and process conditions of different embodiments of the present invention

[0077] Comparison items Example 1 Example 2 Example 3 Alkali treatment conditions 10% NaOH, 80℃, 2h 5% NaOH, 40℃, 6h 18% KOH, 90℃, 1h sludge maturation conditions 8% lime, 60℃, 2h 5% lime, 50℃, 3h 10% lime, 70℃, 1h Alkali activator dosage 0.15 0.1 0.18 28-day average compressive strength (MPa) 17.2 15.3 18.8 Overall evaluation Excellent performance, mild processing conditions, and a balance between cost and energy consumption. It meets basic performance requirements, has the lowest cost and energy consumption, but offers little performance margin. It boasts the best performance, but requires stringent manufacturing conditions, resulting in the highest cost and energy consumption.

[0078] Validity verification: All three examples successfully produced qualified non-fired bricks with a compressive strength exceeding 15 MPa, proving that the process parameter range claimed by this invention is effective.

[0079] Performance Comparison: Example 3, using the highest level of reaction conditions (highest temperature, highest alkali concentration, highest activator dosage), achieved the highest compressive strength (18.8 MPa). Example 2, using the lowest level of reaction conditions, also achieved a compressive strength (15.3 MPa) that met the acceptable standard, but with a smaller performance margin. Example 1, using intermediate-level process parameters, achieved a compressive strength of 17.2 MPa, demonstrating excellent performance and sufficient quality assurance margin.

[0080] Economic and Feasibility Analysis: While Example 3 exhibits the best performance, its higher reaction temperature, higher chemical concentration, and higher dosage imply higher energy consumption and raw material costs. Example 2 has the lowest cost and energy consumption, but its proximity to the lower performance limit may pose certain quality control risks in large-scale industrial production. Example 1 offers relatively mild and easily controllable process conditions, with energy consumption and cost falling between the two, achieving a good balance between high product performance and production economy.

[0081] In summary, the combination of process parameters in Example 1 achieves optimized configuration of production costs and energy consumption while ensuring sufficient margin in product performance.

[0082] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for the co-processing and resource utilization of fiberglass waste and sludge, characterized in that, include: a. Pre-treat fiberglass waste to obtain fiberglass aggregate; b. Pre-treat the sludge to obtain a cementitious material containing sludge clinker; c. The fiberglass aggregate is mixed with the cementitious material, and then pressed and cured to obtain non-fired bricks.

2. The method for co-processing and resource utilization of fiberglass waste and sludge according to claim 1, characterized in that, The pretreatment of fiberglass waste in step a specifically includes: crushing the fiberglass waste and then treating it with alkaline solution to remove some of the resin on the surface of the fiberglass and modify its surface.

3. The method for co-processing and resource utilization of fiberglass waste and sludge according to claim 1, characterized in that, The conditions for alkaline treatment are as follows: the alkaline solution is NaOH or KOH solution with a concentration of 5%-18%, the liquid-to-solid ratio is 8:1-15:1, and the reaction temperature is 40℃-90℃.

4. The method for co-processing and resource utilization of fiberglass waste and sludge according to claim 2, characterized in that, The pretreatment steps for fiberglass waste also include: The material treated with alkali solution is subjected to solid-liquid separation, washing and drying, followed by deep crushing and screening to obtain the fiberglass aggregate with a particle size of 0.3mm-4mm.

5. The method for co-processing and resource utilization of fiberglass waste and sludge according to claim 1, characterized in that, The specific steps of pretreating the sludge in step b are as follows: mixing dewatered sludge with lime for slaking treatment to obtain the sludge clinker.

6. The method for co-processing and resource utilization of fiberglass waste and sludge according to claim 1, characterized in that, The cementitious material is a mixture of sludge clinker, cement and fly ash in a preset ratio.

7. The method for co-processing and resource utilization of fiberglass waste and sludge according to claim 1, characterized in that, After the fiberglass aggregate is mixed with recycled coarse aggregate and recycled fine aggregate for concrete, it is mixed with the cementitious material as a composite aggregate.

8. The method for co-processing and resource utilization of fiberglass waste and sludge according to claim 1, characterized in that, In step c, when the fiberglass aggregate is mixed with the cementitious material, an alkali activator is also added to activate the cementitious material.

9. The method for co-processing and resource utilization of fiberglass waste and sludge according to claim 8, characterized in that, The alkaline activator is a mixture of NaOH and Na2SiO3.

10. The method for co-processing and resource utilization of fiberglass waste and sludge according to claim 1, characterized in that, The unfired bricks produced contain the following components by mass percentage: 9.8%-11.6% fiberglass aggregate, 29.4%-34.8% recycled coarse aggregate for concrete, 19.6%-23.2% recycled fine aggregate for concrete, 4-5.5% dewatered sludge, 16-22% cement, and 8-11% fly ash.

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