Mine underground multi-working-condition composite phase change material cooling clothes and manufacturing method thereof

Abstract

The invention belongs to the technical field of coal mine underground individual protection, and particularly relates to a mine underground multi-working-condition composite phase change material cooling garment which comprises a cooling garment body, a plurality of cold storage bag side pockets and a plurality of cold storage bags, and the cold storage bag side pockets are arranged at the chest position, the abdomen position and the lower portion of the back of the cooling garment body respectively. The cold storage bag side pocket is used for containing a cold storage bag, and a composite phase change material is packaged in the cold storage bag. The invention further provides a manufacturing method of the mine underground multi-working-condition composite phase change material cooling clothes. The thermal comfort and safety of operators in the high-temperature environment are improved, on-demand regulation and control of the cooling efficiency are achieved through modular design, the effective cooling time is remarkably prolonged, and energy consumption and maintenance cost are reduced. The cooling suit can stably operate under the continuous underground working condition, has good environmental adaptability and reliability, is suitable for different actual working conditions, and has important popularization value and application prospects.

Description

A multi-condition composite phase change material cooling suit for underground mining and its manufacturing method Technical Field

[0001] This invention relates to the field of personal protective equipment technology in coal mines, specifically to a multi-condition composite phase change material cooling suit for underground mining and its manufacturing method. Background Technology

[0002] Due to factors such as ground temperature, mechanical heat dissipation, and poor ventilation, the working environment temperature in coal mines often reaches 28-45℃. Long-term high-temperature work can easily lead to heatstroke, decreased physical strength, and even safety accidents. Therefore, mine cooling suits have become an essential personal protective equipment.

[0003] Currently, mining cooling suits mainly use single organic or inorganic phase change materials as the cold storage core, but there are many technical bottlenecks. For example, single organic phase change materials (such as conventional paraffin wax) have low latent heat of phase change (≤200J / g) and a thermal conductivity of only 0.2-0.3W / (m·K). They are prone to leakage after phase change and have poor flame retardancy (oxygen index ≤21%), which cannot meet the explosion-proof requirements of underground coal mines. Single inorganic phase change materials (such as CaCl2·6H2O) have higher latent heat (240-280J / g), but they suffer from severe supercooling and phase separation. After 50 cycles of use, the latent heat decay rate is higher than 20%, and they are corrosive to the packaging material. At the same time, the interatomic interaction in the phase change material matrix is ​​weak, and the molecular arrangement is disordered during solid-liquid phase change, which leads to the obstruction of the heat transfer core carrier (phonons) movement and intensified scattering, further reducing the thermal conductivity and causing the cooling suit's cold storage-release response to lag. The cooling start-up time is generally greater than 5 minutes.

[0004] Furthermore, the ambient temperature, work intensity, and risk level vary significantly under different working conditions in coal mines: the temperature at the tunneling face is 38-45℃ with high work intensity; the temperature at the longwall face is 32-38℃ with complex operations; and the temperature in the monitoring room / inspection area is 28-32℃ with low work intensity. Existing cooling suits lack targeted design, have complex structures that affect operational flexibility, fail to meet safety standards, and their cooling duration is not matched to the working conditions, making it difficult to balance flexibility, thermal stability, comfort, and energy storage requirements. Summary of the Invention

[0005] To address the aforementioned problems, the present invention aims to provide a multi-condition composite phase change material cooling suit for underground mining and its manufacturing method.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is: a multi-condition composite phase change material cooling suit for underground mining, comprising a cooling suit body, multiple cold storage bag inserts and multiple cold storage bags, wherein cold storage bag inserts are respectively provided on the chest, abdomen and lower back of the cooling suit body, the cold storage bag inserts are used to insert the cold storage bags, and the cold storage bags are encapsulated with composite phase change material.

[0007] Furthermore, the cooling garment body is a sleeveless vest structure, and there are a total of 7 cold storage bag pockets, including 1 on each side of the front chest, 1 on each side of the abdomen, and 3 on the lower back.

[0008] Furthermore, the fabric material of the cooling garment body and the cold storage bag insert is a mining flame-retardant and antistatic polyester-cotton blended fabric. The total weight of the cooling garment body and the cold storage bag insert is ≤0.5kg, and the total weight of the cooling garment body, the cold storage bag insert, and the cold storage bag is ≤1.2kg.

[0009] Furthermore, a 3-5mm thick heat insulation cotton layer is sewn inside the cold storage bag insert, and anti-slip rubber strips are fixed to the bottom and sides of the inside of the cold storage bag insert. The bag opening is sealed with Velcro.

[0010] Furthermore, the composite phase change material comprises a phase change material composition, a thermally conductive enhancing material, and a composite additive, wherein the phase change material composition comprises a phase change wax and CaC. 6 O, the phase change wax has a phase change temperature of 32-36℃, a latent heat of 210-230 J / g, and CaC 6 The phase transition temperature of O is 28-32℃, and the latent heat is 240-260J / g; the thermal conductivity enhancement material is expanded graphite, and the composite additives include calcium stearate, boric acid and montmorillonite.

[0011] Furthermore, the composite phase change material is suitable for operating conditions with a target latent heat parameter of 240-260 J / g, wherein the mass fractions of the phase change material composition, thermal conductivity enhancement material, and composite additives are: phase change wax: 60%-65%; CaC 6 O: 28%-33%; Expanded graphite: 3%-5%; In the composite additives, calcium stearate: 1.0%; Boric acid: 0.5%; Montmorillonite: 0.5%.

[0012] Furthermore, the composite phase change material is suitable for operating conditions with a target latent heat parameter of 220-240 J / g, wherein the mass fractions of the phase change material composition, thermal conductivity enhancement material, and composite additives are: phase change wax: 65%-70%; CaC 6 O: 23%-28%; Expanded graphite: 4%-6%; In the composite additives, calcium stearate: 0.8%; Boric acid: 0.6%; Montmorillonite: 0.6%.

[0013] Furthermore, the composite phase change material is suitable for operating conditions with a target latent heat parameter of 200-220 J / g, wherein the mass fractions of the phase change material composition, thermal conductivity enhancement material, and composite additives are: phase change wax: 70%-75%; CaC 6 O: 18%-23%; Expanded graphite: 4%-6%; In the composite additives, calcium stearate: 1.2%; Boric acid: 0.4%; Montmorillonite: 0.4%.

[0014] This invention also provides a method for manufacturing a multi-condition composite phase change material cooling suit for underground mining, specifically including the following steps: Step 1, manufacturing the cooling suit body and the cold storage bag insert; (1) Manufacturing of mine flame-retardant and antistatic polyester-cotton blended fabric: The mine flame-retardant and antistatic polyester-cotton blended fabric includes the following raw materials, the weight fraction of each raw material is: cotton fiber 60%, polyester fiber 35% and silver-plated nylon conductive fiber 5%, wherein the base material of the silver-plated nylon conductive fiber is nylon 6, silver The coating thickness is 0.3-0.5μm; (2) The raw materials of the above-mentioned flame-retardant and antistatic polyester-cotton blended fabric for mining are mixed according to the proportion and then opened, combed, drawn, roving and spinning processes are carried out to obtain warp and weft yarns; (3) The warp and weft yarns are woven in a 2 / 1 right twill weave with the following weaving parameters: warp density 128-136 ends / 10cm, weft density 60-70 ends / 10cm, and fabric weight: 280-320g / m²; (4) The pre-setting and flame-retardant treatment are carried out in sequence. And antistatic treatment: Among them, the pre-forming temperature is 180-200℃; flame retardant treatment is carried out by impregnation with phosphorus-nitrogen intumescent flame retardant, and the amount added is 5%-8% of the total weight of the fabric; antistatic treatment is carried out by impregnation with quaternary ammonium salt antistatic agent, and the amount added is 1%-3% of the total weight of the fabric; (5) Cut and sew to make cooling garment body and cold storage bag insert: cut the treated mining flame retardant and antistatic polyester-cotton blended fabric according to the shape of cooling garment body and cold storage bag insert, sew it with aramid flame retardant thread, the stitch density is ≥12 stitches / 3cm, sew it into cooling garment body, and sew cold storage bag insert on cooling garment body; Step 2, preparation of cold storage bag; A, raw material pretreatment: expanded graphite pretreatment: place expanded graphite in a vacuum drying oven, vacuum dry for 2h-4h under vacuum degree ≥-0.09MPa and temperature 110-120℃ to completely remove adsorbed moisture and avoid affecting the mixing uniformity; CaC 6 O Pretreatment: CaC 6 O. Grind the mixture in a high-speed pulverizer and pass it through a 200-mesh standard sieve to achieve a particle size ≤50μm; B. Melt and mix: Ingredients: Weigh the corresponding proportions of composite phase change material raw materials according to the target latent heat parameters; Melting and stirring: Add the phase change wax to the reaction vessel and heat it to 60℃-70℃ to completely melt it, then add CaC sequentially. 6 O. Add composite additives and expanded graphite, turn on the mixer, stir at 500 r / min, and stir for 30 min at a constant temperature of 55℃-65℃ to form a preliminary mixed slurry; C. Ultrasonic dispersion: Transfer the preliminary mixed slurry obtained in step B to an ultrasonic device, set the power to 200W-300W, the frequency to 20kHz-40kHz, maintain the temperature at 55℃-65℃, and ultrasonically treat for 30-40 min to form a uniform and stable composite phase change material slurry; D. Molding and encapsulation: Molding: Pour the composite phase change material slurry obtained in step C into a mold, and allow it to cool naturally to room temperature to solidify, obtaining a composite phase change material block; Encapsulation: Encapsulate the obtained composite phase change material block at an encapsulation temperature of 120℃-140℃, with an encapsulation strength ≥50N / 15mm; During encapsulation, a three-layer encapsulation structure is used from the inside out: a polytetrafluoroethylene inner layer, an aluminum foil composite film, and a flame-retardant nylon film. The polytetrafluoroethylene inner layer is used to isolate CaCl2. Corrosion by 6H2O; aluminum foil composite film improves sealing and prevents moisture intrusion; flame-retardant nylon film enhances wear resistance; the inner layer of polytetrafluoroethylene has a thickness of 5μm-10μm; E. After sealing, if there is no leakage and the phase change performance is stable, the cold storage bag is obtained; Step 3: Insert the cold storage bags into the cold storage bag inserts according to the needs of different working conditions, specifically: First working condition, tunneling face: 7 cold storage bags, one cold storage bag is inserted into each cold storage bag insert; Second working condition, longwall face: 5 cold storage bags, one cold storage bag is inserted into each of the left and right sides of the abdomen and the lower back; Third working condition, monitoring room or inspection room: 3 cold storage bags, one cold storage bag is inserted into each of the 3 cold storage bag inserts at the lower back.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The manufacturing process of the cold storage bag of the present invention, through raw material pretreatment, melt mixing and ultrasonic dispersion processes, significantly improves the uniformity and thermal stability of the composite phase change material; and the cold storage bag adopts a multi-layer encapsulation structure, effectively solving the CaC problem. 6 The O-type coating addresses the corrosion problem of metal components while enhancing the sealing and durability of the cold storage bag.

[0016] 2. In the composite phase change material of the present invention, the phase change wax and CaC in the phase change material composition... 6 The combination of these two components complements the latent heat stability of the organic phase (phase change wax) and the inorganic phase (CaC). 6 O) has the advantage of high cold storage capacity.

[0017] Expanded graphite, in this invention, has a particle size of 50μm-100μm and a specific surface area ≥800m² / g. The layered porous structure of expanded graphite forms a continuous thermally conductive network in the system, which not only provides channels for phonon transport, reduces the scattering of phonons by disordered molecular arrangement, and improves thermal conductivity, but also adsorbs phase change components through van der Waals forces, suppressing leakage problems in the solid-liquid phase change process.

[0018] In compound additives, calcium stearate acts as a nucleating agent to effectively reduce CaCl2. The supercooling of 6H2O; boric acid as a phase separation inhibitor, used to suppress the inorganic phase (CaCl2). The stratification phenomenon of 6H2O during recycling; montmorillonite as a stability enhancer is used to enhance the agglomeration stability of the system, improve the recycling performance of the composite phase change material, and ensure that the latent heat decay rate is ≤5% after 500 cycles; the three components in the composite additive are combined in a specific ratio to solve the defects of supercooling and phase separation in single inorganic phase change materials, while improving the structural stability of the composite system.

[0019] 3. This invention achieves precise cooling for different working conditions such as tunneling, mining, and inspection through the design of cold storage bags and the configuration of differentiated cold storage bags under different working conditions. The cooling duration is 3-5 hours, and it is suitable for different ambient temperatures of 28-45℃. It solves the design defects of the existing cooling clothing that is "one-size-fits-all". It not only ensures the cooling needs of heavy physical work, but also avoids the waste of resources in light physical work. It achieves efficient cooling of key parts of the human body and greatly improves the personal protective effectiveness in high-temperature working environments.

[0020] 4. Both the cooling suit body and the cold storage bag of this invention meet the requirements for flame retardancy and antistatic properties in underground coal mines, with an oxygen index ≥32% and a surface resistivity of 10. 6 -10 9 Ω, having passed the vertical combustion test, produces no static sparks, making it suitable for underground gas and dust environments, and solving the problem of insufficient safety performance of existing cooling suits.

[0021] 5. The cooling garment of this invention has a simple manufacturing process, and the steps such as ultrasonic dispersion and heat sealing are easy to scale up industrially; the cold storage bag can be repeatedly replaced and used, the garment fabric is wear-resistant and corrosion-resistant, and the overall service life is long; the insert-pocket design facilitates the replacement and maintenance of the cold storage bag, reduces the cost of use, and is suitable for large-scale promotion in underground coal mines.

[0022] 6. The cooling suit of the present invention has the advantages of wearing comfort and work compatibility, with an overall weight of ≤1.2kg and an air permeability of ≥500mm / s, avoiding stuffiness.

[0023] In summary, this invention not only improves the thermal comfort and safety of workers in high-temperature environments, but also achieves on-demand adjustment of cooling efficiency through modular design, significantly extending the effective cooling time and reducing energy consumption and maintenance costs. This cooling suit can operate stably under continuous underground working conditions, possessing good environmental adaptability and reliability, and is suitable for various actual working conditions, demonstrating significant promotional value and application prospects. Attached Figure Description

[0024] Figure 1 is a front structural schematic diagram of a multi-condition composite phase change material cooling suit for underground mining according to the present invention; Figure 2 is a back structural schematic diagram of a multi-condition composite phase change material cooling suit for underground mining according to the present invention; In the figures, 1-cooling suit body; 2-cold storage bag insert; 3-cold storage bag. Detailed Implementation

[0025] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the invention.

[0026] Example 1: As shown in Figures 1-2, a multi-condition composite phase change material cooling suit for underground mining includes a cooling suit body 1, multiple cold storage bag inserts 2 and multiple cold storage bags 3. Cold storage bag inserts 2 are respectively provided on the chest, abdomen and lower back of the cooling suit body 1. The cold storage bag inserts 2 are used to put the cold storage bags 3 into the cold storage bags. The cold storage bags 3 are encapsulated with composite phase change material.

[0027] The cooling garment body 1 is a sleeveless vest structure. It contains seven cold-storage pockets 2: one on each side of the front chest, one on each side of the abdomen, and three on the lower back. This covers the core heat dissipation area of ​​the human body.

[0028] The material of the cooling garment body 1 and the cold storage bag insert 2 is a mining flame-retardant and antistatic polyester-cotton blend fabric. The total weight of the cooling garment body 1 and the cold storage bag insert 2 is ≤0.5kg, and the total weight of the cooling garment body 1, the cold storage bag insert 2 and the cold storage bag 3 is ≤1.2kg.

[0029] The inner side of the cold storage bag insert 2 is sewn with a 3-5mm thick heat insulation cotton layer to reduce the diffusion of cold energy to non-target areas and prolong the cooling duration. Anti-slip rubber strips are fixed to the bottom and sides of the inner side of the cold storage bag insert 2, and the bag opening is sealed with Velcro. A single cold storage bag insert 2 can bear a weight of ≥1kg, adapting to the weight of the cold storage bag 3 and operational impacts. The composite phase change material includes a phase change material composition, a thermally conductive enhancing material, and composite additives. The phase change material composition includes phase change wax and CaC. 6 O, the phase change wax has a phase change temperature of 32-36℃, a latent heat of 210-230 J / g, and CaC 6 The phase transition temperature of O is 28-32℃, and the latent heat is 240-260J / g; the thermal conductivity enhancement material is expanded graphite, and the composite additives include calcium stearate, boric acid and montmorillonite.

[0030] The composite phase change material is suitable for operating conditions with a target latent heat parameter of 240 J / g. The mass fractions of the phase change material composition, thermal conductivity enhancement material, and composite additives are as follows: phase change wax: 60%; CaC... 6 O: 33%; Expanded graphite: 5%; In the composite additives, calcium stearate: 1.0%; Boric acid: 0.5%; Montmorillonite: 0.5%.

[0031] Example 2: The difference from Example 1 is that the composite phase change material is suitable for a target latent heat parameter of 260 J / g. The mass fractions of the phase change material composition, thermal conductivity enhancement material, and composite additives are as follows: phase change wax: 65%; CaC... 6 O: 30%; Expanded graphite: 3%; In the composite additives, calcium stearate: 1.0%; Boric acid: 0.5%; Montmorillonite: 0.5%.

[0032] Example 3: The difference from Example 1 is that the composite phase change material is suitable for a target latent heat parameter of 250 J / g. The mass fractions of the phase change material composition, thermal conductivity enhancement material, and composite additives are as follows: phase change wax: 65%; CaC... 6 O: 28%; Expanded graphite: 5%; In the composite additives, calcium stearate: 1.0%; Boric acid: 0.5%; Montmorillonite: 0.5%.

[0033] Example 4: The difference from Example 1 is that the composite phase change material is suitable for a target latent heat parameter of 220 J / g. The mass fractions of the phase change material composition, thermal conductivity enhancement material, and composite additives are as follows: phase change wax: 70%; CaC... 6 O: 23%; Expanded graphite: 5%; In the composite additives, calcium stearate: 0.8%; Boric acid: 0.6%; Montmorillonite: 0.6%.

[0034] Example 5: The difference from Example 4 is that the composite phase change material is suitable for a target latent heat parameter of 240 J / g. The mass fractions of the phase change material composition, thermal conductivity enhancement material, and composite additives are: phase change wax: 65%; CaC... 6 O: 27%; Expanded graphite: 6%; In the composite additives, calcium stearate: 0.8%; Boric acid: 0.6%; Montmorillonite: 0.6%.

[0035] Example 6: The difference from Example 4 is that the composite phase change material is suitable for a target latent heat parameter of 230 J / g. The mass fractions of the phase change material composition, thermal conductivity enhancement material, and composite additives are as follows: phase change wax: 66%; CaC... 6 O: 28%; Expanded graphite: 4%; In the composite additives, calcium stearate: 0.8%; Boric acid: 0.6%; Montmorillonite: 0.6%.

[0036] Example 7: The difference from Example 1 is that the composite phase change material is suitable for a target latent heat parameter of 200 J / g, wherein the mass fractions of the phase change material composition, thermal conductivity enhancement material, and composite additives are: phase change wax: 70%; CaC 6 O: 23%; Expanded graphite: 5%; In the composite additives, calcium stearate: 1.2%; Boric acid: 0.4%; Montmorillonite: 0.4%.

[0037] Example 8: The difference from Example 1 is that the composite phase change material is suitable for a target latent heat parameter of 210 J / g, wherein the mass fractions of the phase change material composition, thermal conductivity enhancement material, and composite additives are: phase change wax: 75%; CaC 6 O: 19%; Expanded graphite: 4%; In the composite additives, calcium stearate: 1.2%; Boric acid: 0.4%; Montmorillonite: 0.4%.

[0038] Example 9: The difference from Example 1 is that the composite phase change material is suitable for a target latent heat parameter of 220 J / g, wherein the mass fractions of the phase change material composition, thermal conductivity enhancement material, and composite additives are: phase change wax: 74%; CaC 6 O: 18%; Expanded graphite: 6%; In the composite additives, calcium stearate: 1.2%; Boric acid: 0.4%; Montmorillonite: 0.4%.

[0039] The composite phase change materials in Examples 1 to 9 of this invention exhibit the following properties: thermal conductivity can reach 0.9-1.5 W / (m·K), which is 3-5 times higher than that of single phase change wax; phonon transmission efficiency is increased by more than 40%; cooling response time is shortened to ≤5 min, solving the problems of poor thermal conductivity and lag in existing materials; supercooling is ≤3℃; latent heat decay rate is ≤5% after 500 cycles; there is no leakage or corrosion, overcoming the stability defects of single materials.

[0040] Example 10: This example provides a method for manufacturing a multi-condition composite phase change material cooling suit for underground mining, specifically including the following steps: Step 1, manufacturing the cooling suit body 1 and the cold storage bag insert 2; (1) Manufacturing of the mine flame retardant and antistatic polyester-cotton blended fabric: The mine flame retardant and antistatic polyester-cotton blended fabric includes the following raw materials, the weight fraction of each raw material is: cotton fiber 60%, polyester fiber 35% and silver-plated nylon conductive fiber 5%, wherein the base material of the silver-plated nylon conductive fiber is nylon 6, the silver plating thickness is 0.3-0.5μm, and the volume resistivity is ≤10 -2 Ω cm; (2) The raw materials of the above-mentioned flame-retardant and antistatic polyester-cotton blended fabric for mining are mixed according to the proportion and then subjected to opening, combing, drawing, roving and spinning processes to obtain warp and weft yarns; (3) The warp and weft yarns are woven in a 2 / 1 right twill weave, with warp yarns of 16S / 1 single yarn and weft yarns of 16S / 1 single yarn. The weaving parameters are warp density of 128-136 ends / 10cm, weft density of 60-70 ends / 10cm, and fabric weight of 280-320g / m²; (4) The pre-setting, flame-retardant treatment and antistatic treatment are carried out in sequence: the pre-setting temperature is 180-200℃. ℃; Flame retardant treatment uses phosphorus-nitrogen intumescent flame retardant (such as PyrovatexCP) for impregnation, with an addition amount of 5%-8% of the total fabric weight, ensuring the fabric's oxygen index ≥32%; Antistatic treatment uses quaternary ammonium salt antistatic agent for impregnation, with an addition amount of 1%-3% of the total fabric weight; The treated mining flame retardant and antistatic polyester-cotton blended fabric was tested, and the test results are as follows: ① Mechanical property test: warp breaking strength ≥800N, weft breaking strength ≥700N; ② Safety performance: oxygen index ≥32%, surface resistivity 1 -1 Ω; ③ Comfort performance: air permeability ≥500mm / s; ④ Flame retardant performance: meets the Class A requirements of GB8965.1-2020 "Flame Retardant Protective Clothing".

[0041] (5) The cooling garment body 1 and the cold storage bag insert 2 are made by cutting and sewing: The mining flame-retardant and antistatic polyester-cotton blended fabric is cut and treated according to the shape of the cooling garment body 1 and the cold storage bag insert 2. It is sewn with aramid flame-retardant thread with a stitch density of ≥12 stitches / 3cm to make the cooling garment body 1. The cold storage bag insert 2 is sewn on the cooling garment body 1. The edge of the cold storage bag insert 2 is double-stitched with a stitch density of ≥12 stitches / 10cm. The dimensions of the sewn cold storage bag insert 2 are: length 11cm, height 16cm, width 2.5cm; Step 2, preparation of cold storage bag 3; A, raw material pretreatment: expanded graphite pretreatment: the expanded graphite is placed in a vacuum drying oven and vacuum dried for 2h-4h under vacuum conditions of ≥-0.09MPa and temperature of 110-120℃ to completely remove the adsorbed moisture and avoid affecting the mixing uniformity; CaC 6 O Pretreatment: CaC 6 O. Grind the mixture in a high-speed pulverizer and pass it through a 200-mesh standard sieve to achieve a particle size ≤50μm; B. Melt and mix: Ingredients: Weigh the corresponding proportions of composite phase change material raw materials according to the target latent heat parameters in Examples 1 to 9; Melting and stirring: Add the phase change wax to the reaction vessel and heat it to 60℃-70℃ to completely melt it, then add CaC sequentially. 6 O. Add composite additives and expanded graphite, turn on the mixer, stir at 500 r / min, and stir for 30 min at a constant temperature of 55℃-65℃ to form a preliminary mixed slurry; C. Ultrasonic dispersion: Transfer the preliminary mixed slurry obtained in step B to an ultrasonic device, set the power to 200W-300W, the frequency to 20kHz-40kHz, maintain the temperature at 55℃-65℃, and ultrasonically treat for 30 min-40 min to form a uniform and stable composite phase change material slurry; D. Molding and encapsulation: Molding: The slurry obtained in step C... The composite phase change material slurry was poured into a mold with dimensions of 11cm in length, 16cm in height, and 2.5cm in width. It was then allowed to cool naturally to room temperature and solidify, resulting in a composite phase change material block. The block was then encapsulated at 120℃-140℃ with a sealing strength ≥50N / 15mm. The cold storage bag 3 had dimensions of 10cm in length, 15cm in height, and 2cm in width. The encapsulation employed a three-layer structure: an inner PTFE layer, an aluminum foil composite film, and a flame-retardant nylon film. The PTFE inner layer was used to isolate CaCl2. Corrosion by 6H2O; aluminum foil composite film improves sealing and prevents moisture intrusion; flame-retardant nylon film enhances wear resistance; the inner layer of polytetrafluoroethylene has a thickness of 5μm-10μm; E. After sealing, it is tested to be leak-free and have stable phase change performance, thus obtaining the cold storage bag 3; the testing method is: after sealing, immerse the cold storage bag 3 in water for 30 minutes, and it is qualified if there is no leakage, ensuring no risk of corrosion and leakage during use; Step 3: Insert the cold storage bag 3 into the cold storage according to the requirements of different working conditions. Specifically, in the case of the inserted bag 2, there are: the first working condition, the tunneling face: there are 7 cold storage bags 3, and one cold storage bag 3 is inserted into each cold storage bag 2; the second working condition, the mining face: there are 5 cold storage bags 3, and one cold storage bag 3 is inserted into each of the left and right sides of the abdomen and the lower back of each cold storage bag 2; the third working condition, the monitoring room or inspection room: there are 3 cold storage bags 3, and one cold storage bag 3 is inserted into each of the 3 cold storage bag 2 in the lower back.

[0042] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A multi-condition composite phase change material cooling suit for underground mining, characterized in that: The garment includes a cooling suit body, multiple cold storage bag inserts, and multiple cold storage bags. Cold storage bag inserts are provided on the front chest, abdomen, and lower back of the cooling suit body. The cold storage bag inserts are used to insert the cold storage bags, and the cold storage bags are encapsulated with composite phase change material.

2. The multi-condition composite phase change material cooling suit for underground mining as described in claim 1, characterized in that: The cooling garment body is a sleeveless vest structure, and there are a total of 7 cold storage bag pockets, including 1 on each side of the front chest, 1 on each side of the abdomen, and 3 on the lower back.

3. The multi-condition composite phase change material cooling suit for underground mining as described in claim 1, characterized in that: The material of the cooling garment body and the cold storage bag insert is a mining flame-retardant and antistatic polyester-cotton blend fabric. The total weight of the cooling garment body and the cold storage bag insert is ≤0.5kg, and the total weight of the cooling garment body, the cold storage bag insert, and the cold storage bag is ≤1.2kg.

4. The multi-condition composite phase change material cooling suit for underground mining as described in claim 1, characterized in that: The inner side of the cold storage bag insert is sewn with a 3-5mm thick heat insulation cotton layer, and anti-slip rubber strips are fixed to the bottom and sides of the inner side of the cold storage bag insert. The bag opening is sealed with Velcro.

5. The multi-condition composite phase change material cooling suit for underground mining as described in claim 1, characterized in that: The composite phase change material comprises a phase change material composition, a thermally conductive enhancing material, and a composite additive. The phase change material composition comprises a phase change wax and CaC. 6 O, the phase change wax has a phase change temperature of 32-36℃, a latent heat of 210-230 J / g, and CaC 6 The phase transition temperature of O is 28-32℃, and the latent heat is 240-260J / g; the thermal conductivity enhancement material is expanded graphite, and the composite additives include calcium stearate, boric acid and montmorillonite.

6. The multi-condition composite phase change material cooling suit for underground mining as described in claim 5, characterized in that: The composite phase change material is suitable for operating conditions with a target latent heat parameter of 240-260 J / g. The mass fractions of the phase change material composition, thermal conductivity enhancing material, and composite additives are as follows: phase change wax: 60%-65%; CaC... 6 O: 28%-33%; Expanded graphite: 3%-5%; In the composite additives, calcium stearate: 1.0%; Boric acid: 0.5%; Montmorillonite: 0.5%.

7. The multi-condition composite phase change material cooling suit for underground mining as described in claim 5, characterized in that: The composite phase change material is suitable for operating conditions with a target latent heat parameter of 220-240 J / g. The mass fractions of the phase change material composition, thermal conductivity enhancement material, and composite additives are as follows: phase change wax: 65%-70%; CaC... 6 O: 23%-28%; Expanded graphite: 4%-6%; In the composite additives, calcium stearate: 0.8%; Boric acid: 0.6%; Montmorillonite: 0.6%.

8. The multi-condition composite phase change material cooling suit for underground mining as described in claim 5, characterized in that: The composite phase change material is suitable for operating conditions with a target latent heat parameter of 200-220 J / g. The mass fractions of the phase change material composition, thermal conductivity enhancing material, and composite additives are as follows: phase change wax: 70%-75%; CaC... 6 O: 18%-23%; Expanded graphite: 4%-6%; In the composite additives, calcium stearate: 1.2%; Boric acid: 0.4%; Montmorillonite: 0.4%.

9. A method for manufacturing a multi-condition composite phase change material cooling suit for underground mining as described in any one of claims 1-8, characterized in that, Specifically, the following steps are included: Step 1: Making the cooling garment body and the cold storage bag insert; (1) Making the mine flame retardant and antistatic polyester-cotton blended fabric: The mine flame retardant and antistatic polyester-cotton blended fabric includes the following raw materials, the weight fraction of each raw material is: 60% cotton fiber, 35% polyester fiber and 5% silver-plated nylon conductive fiber, wherein the base material of the silver-plated nylon conductive fiber is nylon 6, and the silver plating thickness is 0.3-0.5μm; (2) After mixing the raw materials of the above-mentioned mine flame retardant and antistatic polyester-cotton blended fabric according to the ratio, the opening, combing, drawing, roving and spinning processes are carried out to obtain warp and weft yarns; (3) The warp and weft yarns are woven in a 2 / 1 right twill weave, the weaving parameters are warp density 128-136 ends / 10cm, weft density 60-70 ends / 10cm, and fabric weight: 280-320g / m²; (4) The pre-forming, flame retardant treatment and antistatic treatment are carried out in sequence: wherein, the pre-forming temperature is 180- 200℃; flame retardant treatment is carried out by impregnation with phosphorus-nitrogen intumescent flame retardant, and the amount added is 5%-8% of the total weight of the fabric; antistatic treatment is carried out by impregnation with quaternary ammonium salt antistatic agent, and the amount added is 1%-3% of the total weight of the fabric; (5) the cooling garment body and cold storage bag insert are made by cutting and sewing: the mining flame retardant and antistatic polyester-cotton blended fabric after cutting and treatment according to the shape of the cooling garment body and the cold storage bag insert is sewn with aramid flame retardant thread, the stitch density is ≥12 stitches / 3cm, and the cooling garment body is sewn, and the cold storage bag insert is sewn on the cooling garment body; Step 2, preparation of cold storage bag; A, raw material pretreatment: expanded graphite pretreatment: the expanded graphite is placed in a vacuum drying oven and vacuum dried for 2h-4h under vacuum degree ≥-0.09MPa and temperature 110-120℃ to completely remove adsorbed moisture and avoid affecting the mixing uniformity; CaC 6 O Pretreatment: CaC 6 O. Grind the material in a high-speed pulverizer and pass it through a 200-mesh standard sieve to achieve a particle size ≤50μm; B. Melt and mix: Ingredients: Weigh the composite phase change material raw materials in the corresponding proportions according to claim 6, 7, or 8, based on the target latent heat parameters; Melting and stirring: Add the phase change wax to the reaction vessel and heat it to 60℃-70℃ to completely melt it, then add CaC sequentially. 6 O. Add composite additives and expanded graphite, turn on the mixer, stir at 500 r / min, and stir for 30 min at a constant temperature of 55℃-65℃ to form a preliminary mixed slurry; C. Ultrasonic dispersion: Transfer the preliminary mixed slurry obtained in step B to an ultrasonic device, set the power to 200W-300W, the frequency to 20kHz-40kHz, maintain the temperature at 55℃-65℃, and ultrasonically treat for 30-40 min to form a uniform and stable composite phase change material slurry; D. Molding and encapsulation: Molding: Pour the composite phase change material slurry obtained in step C into a mold, and allow it to cool naturally to room temperature to solidify, obtaining a composite phase change material block; Encapsulation: Encapsulate the obtained composite phase change material block at an encapsulation temperature of 120℃-140℃, with an encapsulation strength ≥50N / 15mm; During encapsulation, a three-layer encapsulation structure is used from the inside out: a polytetrafluoroethylene inner layer, an aluminum foil composite film, and a flame-retardant nylon film. The polytetrafluoroethylene inner layer is used to isolate CaCl2. Corrosion by 6H2O; aluminum foil composite film improves sealing and prevents moisture intrusion; flame-retardant nylon film enhances wear resistance; the inner layer of polytetrafluoroethylene has a thickness of 5μm-10μm; E. After sealing, if there is no leakage and the phase change performance is stable, the cold storage bag is obtained; Step 3: Insert the cold storage bags into the cold storage bag inserts according to the needs of different working conditions, specifically: First working condition, tunneling face: 7 cold storage bags, one cold storage bag is inserted into each cold storage bag insert; Second working condition, longwall face: 5 cold storage bags, one cold storage bag is inserted into each of the left and right sides of the abdomen and the lower back; Third working condition, monitoring room or inspection room: 3 cold storage bags, one cold storage bag is inserted into each of the 3 cold storage bag inserts at the lower back.

Images