CN104177120A - Preparation method of low-cost light-weight fly ash porous thermal-insulation material - Google Patents
Preparation method of low-cost light-weight fly ash porous thermal-insulation material Download PDFInfo
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- CN104177120A CN104177120A CN201410398632.8A CN201410398632A CN104177120A CN 104177120 A CN104177120 A CN 104177120A CN 201410398632 A CN201410398632 A CN 201410398632A CN 104177120 A CN104177120 A CN 104177120A
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Abstract
The invention relates to a preparation method of a low-cost light-weight fly ash porous thermal-insulation material. The method comprises the following steps: (1) pretreating raw materials; (2) adding fly ash, waste glass powder, clay, water and a thickener into a ball mill, and mixing; (3) adding a foaming agent, and foaming; (4) injecting; (5) stripping, and drying; (6) sintering; and (7) carrying out waterproofing treatment. The porosity of the porous thermal-insulation material is 86.3-94.5%, the volume density is 0.17-0.30 g/cm<3>, the heat conductivity coefficient is 0.04-0.08 W/(m.K), the compression strength is 0.3-1.07 MPa, and the water absorptivity can be lowered to 10%. The thermal-insulation material has the advantages of low heat conductivity, low specific gravity, favorable heat stability, low water absorptivity and the like. By using the industrial waste fly ash as the main raw material, the method provides a low-cost high-added-value simple-technical-process technical line for comprehensive utilization of fly ash.
Description
Technical field
The invention belongs to the lagging material technical field that is applied to civil engineering, be specifically related to a kind of preparation of low cost light flyash porous insulation material.
Background technology
China is energy big country, the generating of present stage is mainly to rely on heat power plant, and heat power plant's burning of coal meeting produces a large amount of flyash, although there is part flyash to be applied to the building fields such as cement concrete, but major part is used as the weighting material in roadbed and pit, environment and human health are caused to very large threat.And China's energy lacks relatively, energy consumption particularly building energy consumes hugely, how effectively to utilize waste material to reduce energy consumption and has just become the one effective ways of promoting economic development.The external-wall heat-insulation material that China uses present stage is mainly organic insulation material, is easy to initiation fire, as the Olympic Sports Center, 08 year Jinan fire, 09 year CCTV's new address building fire etc.But the research and development of inorganic heat insulation material are also in relatively backward status.The lagging material of the appropriate application of China at present remains taking conventional expanded heat insulating pearlite material as main, and persistence is poor, has very large application limitation.Although the report that has some to utilize flyash synthesizing inorganic lagging material at present, the addition content of flyash is all fewer, and sintering temperature is higher, complex process, and therefore cost is higher, and the processing and utilizing to waste and save energy do not have large improvement.
Summary of the invention
The object of the invention is to utilize in a large number trade waste flyash, cullet etc. to develop the low cost lightweight porous heat insulating material of excellent performance, realize the Sustainable development of the energy, and reduce corresponding environmental pollution.
The concrete operation step of preparation low cost light flyash porous insulation material is as follows:
(1) raw materials pretreatment
Flyash, cullet powder and clay are crossed respectively to 100 mesh sieves; Described flyash main component is aluminium sesquioxide and silicon oxide, and described clay main component is aluminium sesquioxide and silicon oxide, and the main component of described cullet powder is silicon oxide and calcium oxide;
(2) batch mixing
80～85 parts of flyash, 10～15 parts of cullet powder, 5～10 parts of clays, 186～233 parts of water and 0.1～0.8 part of thickening material are added in ball mill, the rotating speed of ball mill is 240r/min, ball milling 15～24h, obtains the slurry that stable solid load is 30～40wt%;
(3) foaming
In 100 parts of slurries, add 0.2～0.4 part of whipping agent, stir foaming, mixing speed is not less than 800 r/min, and churning time is not less than 3min, obtains foamed slurry;
(4) slip casting
Foamed slurry is poured in grinding tool, and under normal temperature, static 15～24h, obtains base substrate;
(5) demoulding is dry
Under base substrate normal temperature, be dried to constant weight, obtain porous insulation material base substrate;
(6) sintering
By porous insulation material base substrate high temperature sintering, sintering schedule is: before 650 DEG C, sintering rate is 2 DEG C/min, and is incubated 60min at 650 DEG C, temperature rise rate is 5 DEG C/min after 650 DEG C, until 800～1000 DEG C of outlet temperatures, and be incubated 2～3h, be cooled to room temperature, obtain porous insulation material;
(7) WATER REPELLENT
The laboratory sample that sintering is obtained is removed surface impurity, sprays silica-based waterproof agent at the surface uniform of porous insulation material, and temperature 60 C is dried to constant weight, and the porosity of gained porous insulation material is 86.3～94.5%, and volume density is 0.17～0.30g/cm
3, thermal conductivity is 0.04～0.08W/ (mK), and ultimate compression strength is 0.3～1.07MPa, and water-intake rate can be down to 10%.
The present invention's useful technique effect compared with prior art embodies in the following areas:
1, the lagging material that prepared by the present invention is taking industrial waste flyash, cullet etc. as main raw material(s), and the addition content of flyash is larger, has both solved environmental problem, again for the comprehensive utilization of flyash provides a kind of high added value method;
2, the present invention combines mechanical foaming and injection forming, and the method that adopts physical mechanical to stir foams, simple to operate, does not introduce the chemical substance of poisonous or contaminate environment, not only cost-saving but also safety and environmental protection; The slurry having foamed is directly poured moulding in gypsum mold into, and technique is simple, with short production cycle; Sintering temperature is lower, greatly reduces the production cost of lagging material;
3, the porous insulation material shape that prepared by the present invention is easier to control, and sample surfaces is smooth, and porosity is 86.3～94.5%, and volume density is 0.17～0.30g/cm
3, thermal conductivity is 0.04～0.08W/ (mK), ultimate compression strength is 0.3～1.07MPa, meets the requirement of lagging material;
4, the present invention is studied the higher problem of the general water-intake rate of inorganic heat insulation material, by spraying silica-based waterproof agent, the water-intake rate of lagging material is down to 10%, meets the demand to lagging material.
Brief description of the drawings
Fig. 1 is the intact sample figure of goods of the present invention.
Fig. 2 is the photo of the scanning electronic microscope (SEM) of embodiment 1 section.
specific implementation method
Below in conjunction with accompanying drawing, by example, the present invention is further described.
Following instance flyash used is all from fuel-burning power plant, Hefei, and main component is aluminium sesquioxide (Al
2o
3) and silicon oxide (SiO
2), clay used is all from locality, Hefei, and main component is aluminium sesquioxide (Al
2o
3) and silicon oxide (SiO
2); Cullet powder is that the glass going out of use obtains through pulverizing, and main component is silicon oxide (SiO
2) and calcium oxide (CaO).
Embodiment 1:
Raw materials used and weight is: flyash 80g, cullet powder 15g, clay 5 g, thickening material sodium polyacrylate 0.5 g, whipping agent sodium lauryl sulphate (K12) 0.3 g, water 186g.
(1) flyash, cullet and clay are crossed respectively to 100 mesh sieves; (2) by filling a prescription flyash, cullet powder, clay, thickening material sodium polyacrylate and water, ball milling 24h in planetary ball mill, the rotating speed of ball mill is 240r/min, is mixed with the slurry that solid load is 35wt%; In ball mill, the ratio of material and abrading-ball is 1:3; For ensureing the mixing space of material, the Intake Quantity of material is 1/3 of ball grinder capacity.(3) take the slurry 100g that ball milling is good, add 0.3g sodium lauryl sulphate, under the rotating speed of 1000r/min, stir 3min, slurry produces a large amount of foams, and volumetric expansion is to 3.3 times of left and right of original volume; (4) foamed slurry is directly poured in gypsum grinding tool, left standstill 24h; (5), by the base substrate demoulding, be at room temperature dried to constant weight; (6) by dried base substrate sintering in high temperature sintering furnace, sintering schedule is: before 650 DEG C, sintering rate is 2 DEG C/min, and is incubated 60min in 650 DEG C, after 650 DEG C, temperature rise rate is 5 DEG C/min, until 1000 DEG C, and be incubated 2h, obtain porous insulation material; (7) by porous material surface Impurity removal, surface uniform sprays silica-based waterproof agent, is placed in the loft drier of 60 DEG C and is dried to constant weight.
The porosity of gained porous insulation material is 90.7%, and volume density is 0.203g/cm
3, thermal conductivity is 0.0624W/ (mK), and ultimate compression strength is 0.73MPa, and water-intake rate is 14%.Obtained sample pictorial diagram is shown in Fig. 1, and Fig. 2 is shown in by the photo of the scanning electronic microscope (SEM) of lightweight porous heat insulating material section.
Embodiment 2:
Raw materials used and weight is: flyash 85g, cullet powder 10g, clay 5 g, thickening material sodium polyacrylate 0.1 g, whipping agent sodium lauryl sulphate (K12) 0.4 g, water 233g.
(1) flyash, cullet and clay are crossed to 100 mesh sieves; (2) by filling a prescription flyash, cullet powder, clay, thickening material sodium polyacrylate and water, ball milling 24h in planetary ball mill, the rotating speed of ball mill is 240r/min, is mixed with the slurry that solid load is 30.2wt%; In ball mill, the ratio of material and abrading-ball is 1:4; For ensureing the mixing space of material, the Intake Quantity of material is 1/4 of ball grinder capacity.(3) take the slurry 100g that ball milling is good, add 0.4g sodium lauryl sulphate, under the rotating speed of 1000r/min, stir 4min, slurry produces a large amount of foams, and volumetric expansion is to 3 times of left and right of original volume; (4) foamed slurry is directly poured in gypsum grinding tool, left standstill 24h; (5), by the base substrate demoulding, be at room temperature dried to constant weight; (6) by dried base substrate sintering in high temperature sintering furnace, sintering schedule is: before 650 DEG C, sintering rate is 2 DEG C/min, and is incubated 60min in 650 DEG C, after 650 DEG C, temperature rise rate is 5 DEG C/min, until 950 DEG C, and be incubated 2h, obtain porous insulation material; (7) by porous material surface Impurity removal, surface uniform sprays silica-based waterproof agent, is placed in the loft drier of 60 DEG C and is dried to constant weight.
The porosity of gained porous insulation material is 93.46%, and volume density is 0.197g/cm3, and thermal conductivity is 0.059W/ (mK), and ultimate compression strength is 0.65MPa, and water-intake rate is 17%.
Embodiment 3:
Raw materials used and weight is: flyash 80g, cullet powder 10g, clay 10 g, thickening material sodium polyacrylate 0.5 g, whipping agent sodium lauryl sulphate (K12) 0.2g, water 233g.
(1) flyash, cullet and clay are crossed to 100 mesh sieves; (2) by filling a prescription flyash, cullet powder, clay, thickening material sodium polyacrylate and water, ball milling 24h in planetary ball mill, the rotating speed of ball mill is 240r/min, is mixed with the slurry that solid load is 31.2wt%; In ball mill, the ratio of material and abrading-ball is 1:3; For ensureing the mixing space of material, the Intake Quantity of material is 1/5 of ball grinder capacity.(3) take the slurry 100g that ball milling is good, add 0.2g Sodium dodecylbenzene sulfonate, under the rotating speed of 1000 r/min, stir 4min, slurry produces a large amount of foams, and volumetric expansion is to 3 times of left and right of original volume; (4) foamed slurry is directly poured in gypsum grinding tool, left standstill 24h; (5), by the base substrate demoulding, be at room temperature dried to constant weight; (6) by dried base substrate sintering in high temperature sintering furnace, sintering schedule is: before 650 DEG C, sintering rate is 2 DEG C/min, and is incubated 60min in 650 DEG C, after 650 DEG C, temperature rise rate is 5 DEG C/min, until 900 DEG C, and be incubated 2h, obtain porous insulation material; (7) by porous material surface Impurity removal, surface uniform sprays silica-based waterproof agent, is placed in the loft drier of 60 DEG C and is dried to constant weight.
The porosity of gained porous insulation material is 85.76%, and volume density is 0.294g/cm
3, thermal conductivity is 0.0673W/ (mK), and ultimate compression strength is 0.93MPa, and water-intake rate is 11%.
Embodiment 4:
Raw materials used and weight is: flyash 85g, cullet powder 10g, clay 5 g, thickening material sodium polyacrylate 0.8 g, whipping agent sodium lauryl sulphate (K12) 0.2g, water 186g.
(1) flyash, cullet and clay are crossed to 100 mesh sieves; (2) by filling a prescription flyash, cullet powder, clay, thickening material sodium polyacrylate and water, ball milling 24h in planetary ball mill, the rotating speed of ball mill is 240r/min, is mixed with the slurry that solid load is 35.1wt%; In ball mill, the ratio of material and abrading-ball is 1:5; For ensureing the mixing space of material, the Intake Quantity of material is 1/3 of ball grinder capacity.(3) take the slurry 100g that ball milling is good, add 0.2g sodium lauryl sulphate, under the rotating speed of 1000 r/min, stir 5min, slurry produces a large amount of foams, and volumetric expansion is to 3.2 times of left and right of original volume; (4) foamed slurry is directly poured in gypsum grinding tool, left standstill 24h; (5), by the base substrate demoulding, be at room temperature dried to constant weight; (6) by dried base substrate sintering in high temperature sintering furnace, sintering schedule is: before 650 DEG C, sintering rate is 2 DEG C/min, and is incubated 60min in 650 DEG C, after 650 DEG C, temperature rise rate is 5 DEG C/min, until 850 DEG C, and be incubated 2 hours, obtain porous insulation material; (7) by porous material surface Impurity removal, surface uniform sprays silica-based waterproof agent, is placed in the loft drier of 60 DEG C and is dried to constant weight.
The porosity of gained porous insulation material is 90.09%, and volume density is 0.264g/cm
3, thermal conductivity is 0.0657W/ (mK), ultimate compression strength is 0.67MPa.Water-intake rate is 13%.
Claims (6)
1. a preparation method for low cost light flyash porous insulation material, is characterized in that: concrete preparation manipulation step is as follows:
(1) raw materials pretreatment
Flyash, cullet powder and clay are crossed respectively to 100 mesh sieves; Described flyash main component is aluminium sesquioxide and silicon oxide, and described clay main component is aluminium sesquioxide and silicon oxide, and the main component of described cullet powder is silicon oxide and calcium oxide;
(2) batch mixing
80～85 parts of flyash, 10～15 parts of cullet powder, 5～10 parts of clays, 186～233 parts of water and 0.1～0.8 part of thickening material are added in ball mill, the rotating speed of ball mill is 240r/min, ball milling 15～24h, obtains the slurry that stable solid load is 30～40wt%;
(3) foaming
In 100 parts of slurries, add 0.2～0.4 part of whipping agent, stir foaming, mixing speed is not less than 800 r/min, and churning time is not less than 3min, obtains foamed slurry;
(4) slip casting
Foamed slurry is poured in grinding tool, and under normal temperature, static 15～24h, obtains base substrate;
(5) demoulding is dry
Under base substrate normal temperature, be dried to constant weight, obtain porous insulation material base substrate;
(6) sintering
By porous insulation material base substrate high temperature sintering, sintering schedule is: before 650 DEG C, sintering rate is 2 DEG C/min, and is incubated 60min at 650 DEG C, temperature rise rate is 5 DEG C/min after 650 DEG C, until 800～1000 DEG C of outlet temperatures, and be incubated 2～3h, be cooled to room temperature, obtain porous insulation material;
(7) WATER REPELLENT
The laboratory sample that sintering is obtained is removed surface impurity, sprays silica-based waterproof agent at the surface uniform of porous insulation material, and temperature 60 C is dried to constant weight, and the porosity of gained porous insulation material is 86.3～94.5%, and volume density is 0.17～0.30g/cm
3, thermal conductivity is 0.04～0.08W/ (mK), and ultimate compression strength is 0.3～1.07MPa, and water-intake rate can be down to 10%.
2. the preparation method of a kind of low cost light flyash porous insulation material according to claim 1, is characterized in that: described cullet powder is that the glass going out of use obtains through pulverizing.
3. the preparation method of a kind of low cost light flyash porous insulation material according to claim 1, is characterized in that: the described thickening material of step (2) is sodium polyacrylate or Xylo-Mucine.
4. the preparation method of a kind of low cost light flyash porous insulation material according to claim 1, is characterized in that: the described whipping agent of step (3) is sodium lauryl sulphate or Sodium dodecylbenzene sulfonate.
5. the preparation method of a kind of low cost light flyash porous insulation material according to claim 1, is characterized in that: in the ball mill of step (2), the ratio of material and abrading-ball is 1:3～1:5; For ensureing the mixing space of material, the Intake Quantity of material is 1/3～1/5 of ball grinder capacity.
6. the preparation method of a kind of low cost light flyash porous insulation material according to claim 1, is characterized in that: the mould described in step (4) is gypsum mold.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104650519A (en) * | 2015-03-13 | 2015-05-27 | 苏州能华节能环保科技有限公司 | Porous environment-friendly material and preparation method thereof |
| CN105621891A (en) * | 2015-12-30 | 2016-06-01 | 成都汇华英建筑材料有限公司 | Vitrification foam glass particle and preparation method thereof |
| CN105693278A (en) * | 2016-03-18 | 2016-06-22 | 张平 | Efficient energy-saving environment-friendly heat preservation material and preparing method thereof |
| CN106284710A (en) * | 2016-07-29 | 2017-01-04 | 上海轩颂建筑科技有限公司 | A kind of Novel silicate external-wall heat-insulation material |
| CN107098724A (en) * | 2017-04-28 | 2017-08-29 | 四川翊森热能科技有限责任公司 | The preparation technology of environment protecting thermal insulating material |
| CN113460338A (en) * | 2021-07-02 | 2021-10-01 | 上海航天测控通信研究所 | Multifunctional antenna gravity unloading device |
| CN114573322A (en) * | 2020-12-02 | 2022-06-03 | 河南省大成建设工程有限公司 | Inorganic heat-insulating material |
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| CN1165836A (en) * | 1996-05-16 | 1997-11-26 | 林白 | Foaming shaped compound material |
| CN101550021A (en) * | 2009-05-11 | 2009-10-07 | 大连理工大学 | Method for preparing light spume multi-hole bricks with fly ash |
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2014
- 2014-08-14 CN CN201410398632.8A patent/CN104177120B/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN1165836A (en) * | 1996-05-16 | 1997-11-26 | 林白 | Foaming shaped compound material |
| CN101550021A (en) * | 2009-05-11 | 2009-10-07 | 大连理工大学 | Method for preparing light spume multi-hole bricks with fly ash |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104650519A (en) * | 2015-03-13 | 2015-05-27 | 苏州能华节能环保科技有限公司 | Porous environment-friendly material and preparation method thereof |
| CN105621891A (en) * | 2015-12-30 | 2016-06-01 | 成都汇华英建筑材料有限公司 | Vitrification foam glass particle and preparation method thereof |
| CN105693278A (en) * | 2016-03-18 | 2016-06-22 | 张平 | Efficient energy-saving environment-friendly heat preservation material and preparing method thereof |
| CN106284710A (en) * | 2016-07-29 | 2017-01-04 | 上海轩颂建筑科技有限公司 | A kind of Novel silicate external-wall heat-insulation material |
| CN106284710B (en) * | 2016-07-29 | 2019-06-21 | 上海轩颂建筑科技有限公司 | A kind of silicate external-wall heat-insulation material |
| CN107098724A (en) * | 2017-04-28 | 2017-08-29 | 四川翊森热能科技有限责任公司 | The preparation technology of environment protecting thermal insulating material |
| CN114573322A (en) * | 2020-12-02 | 2022-06-03 | 河南省大成建设工程有限公司 | Inorganic heat-insulating material |
| CN113460338A (en) * | 2021-07-02 | 2021-10-01 | 上海航天测控通信研究所 | Multifunctional antenna gravity unloading device |
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