scholarly journals Preparation of Magnesia Insulation Materials by Calcination of Walnut Shell Powder by Silica Sol Impregnation

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Chi Kang ◽  
Guohua Li ◽  
Jishuo Han ◽  
Shujiang Chen ◽  
Lin Tian ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Bulk Density ◽  
Compression Strength ◽  
Silica Sol ◽  
Walnut Shell ◽  
Insulation Material ◽  
Potassium Oleate ◽  
Foaming Agent ◽  
Increasing Trend ◽  
Shell Powder

In this paper, magnesia porous aggregate was prepared by the foaming method with potassium oleate as the foaming agent. Secondly, the walnut shell powder was impregnated with the silica sol as the pore forming agent, and then, a new magnesia insulation material was prepared by 1300°C sintering. By changing the amount of the walnut shell powder added, the mechanical properties and thermal properties of the materials after sintering were studied. The results show that the sample with 10% walnut shell powder impregnated without the silica sol has a compression strength of 12 MPa. A sample with 10% walnut shell powder treated with the silica sol has a compression strength of 18 MPa. With the increase in the amount of the walnut shell powder added after impregnation, the bulk density, compression strength, and thermal conductivity of the sample all showed a decreasing trend, and the apparent porosity showed an increasing trend. When the additive amount is 20%, the bulk density of the sample is 1.029 g/cm3, and the thermal conductivity is 0.382 W/m K (1050°C).

Preparation foam brick from Iraqi local clay

2020 ◽  
Vol 10 ◽  
Author(s):  
Mahasin F.hadi Al –Kadhemi ◽  
Enas Muhi Hadi ◽  
Rawabi Abdullrazzaq
Keyword(s):  
Thermal Conductivity ◽  
Compressive Strength ◽  
Thermal Insulation ◽  
Firing Temperature ◽  
Compression Strength ◽  
Weight Ratio ◽  
Kaolin Clay ◽  
Local Clay ◽  
Mixture Ratio ◽  
Foaming Agent

Background: In this present study for preparing foam brick by utilization of local kaolin clay and foaming agent for building and, thermal insulation and construction applications. Methods: This paper deals with the development of foam bricks by independent several of variables are (clay mixture ratio, foam solution ratio, forming mixture ratio and firing temperature), so it has been fixing one of this variable randomly and change another gradually regular and then optimum value to return randomly and thus after that select optimum values of these parameter to produce foam bricks this variables are clay mixture ratio (Mullit:Kaolin ratio is 20:80,40:60 and 60:40 weight ratio), Agent solution ratio (foam agent:water ratio is 0.5:20 ,1:20,1.5:20, 2.5:20,3.5:20 and 4.5:20 weight ratio) and forming mixture ratio (clay mixture:foam solution ratio is 45.5:54.5, 48.87:51.13, 51.14:48.86, 53.51:46.49 and 55.6:44.4 weight ratio). Results: Porosity, thermal conductivity and compression strength has been investigated at (9050,1050)ºC, SEM and XRD also carried out at specimen firing at 950ºC .the results show that optimum foam bricks obtained with 60:40 weight ratio of mullite:kaolin, 1.5:20 and 2.5:20 weight ratio of agent : water respectively and forming mixture ratio was (51.14:48.86 )at 950ºC. Conclusion: The specimens prepared in this way have apparent porosity (as high as 0.46%), exhibiting considerable compressive strength (exceeding 5MPa) and low thermal conductivity (about 0.36 (W/m k)).

Preparative Techniques and its Performance of Chemically Foamed Cement Paste

2013 ◽  
Vol 690-693 ◽  
pp. 700-703
Author(s):  
Xin Wei Ma ◽  
Xue Ying Li
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Bulk Density ◽  
Cement Paste ◽  
Expanded Polystyrene ◽  
Mechanical And Thermal Properties ◽  
Insulation Material ◽  
Light Weight ◽  
Preparation Process ◽  
Composite Walls

The foamed cement paste (FCP) is a kind of inorganic insulation material. It is characterized by its light weight, heat-insulating and fire-proofing properties, and the thermal conductivity is close to that of expanded polystyrene (EPS). The foamed cement paste is achieved by means of chemical reaction. The mixture proportion, the preparation process, mechanical and thermal properties are investigated in this paper. The results show that properly mixed paste foams stably, and the bulk density could be controlled. The hardened FCP could be used as insulating filler material in composite walls, as well as blocks for Thermal insulation walls.

scholarly journals Thermal, Physical and Mechanical Performance of Orange Peel Boards: A New Recycled Material for Building Application

2021 ◽  
Vol 13 (14) ◽  
pp. 7945
Author(s):  
Matteo Vitale ◽  
María del Mar Barbero-Barrera ◽  
Santi Maria Cascone
Keyword(s):  
Thermal Conductivity ◽  
Bending Strength ◽  
Mechanical Performance ◽  
Orange Peel ◽  
Insulation Material ◽  
Orange Peels ◽  
Orange Fruit ◽  
Citrus Waste ◽  
Absorption Thickness ◽  
Loss Of Strength

More than 124 million tons of oranges are consumed in the world annually. Transformation of orange fruit generates a huge quantity of waste, largely composed of peels. Some attempts to reuse by-products derived from citrus waste have been proposed for energy production, nutrient source or pharmaceutical, food and cosmetic industries. However, their use in the building sector had not been researched. In this study, orange peels, in five different ratios, from 100% of wet peels to 75% and from 0% of dry peels to 25%, were submitted to a thermo-compression procedure. They were evaluated according to their physical (bulk density, water absorption, thickness swelling, surface soundness and thermal conductivity) and mechanical properties (bending strength and modulus of elasticity). The results showed that orange peels can be used as thermal insulation material. The addition of dried peels makes the structure of the board heterogeneous and thus increases its porosity and causes the loss of strength. Hence, the board with the sole use of wet peel, whose thermal conductivity is 0.065 W/mK while flexural strength is 0.09 MPa, is recommended.

Studies on Thermal Property of Silica Aerogel/Epoxy Composite

2007 ◽  
Vol 546-549 ◽  
pp. 1581-1584 ◽  
Author(s):  
Jiu Peng Zhao ◽  
Deng Teng Ge ◽  
Sai Lei Zhang ◽  
Xi Long Wei
Keyword(s):  
Thermal Conductivity ◽  
Thermal Property ◽  
Epoxy Resin ◽  
Silica Aerogel ◽  
Epoxy Composite ◽  
Transfer Model ◽  
Insulation Material ◽  
Thermal Transfer ◽  
Heat Distortion Temperature ◽  
Ft Ir

Silica aerogel/epoxy composite, a kind of efficient thermal insulation material, was prepared by doping silica aerogel of different sizes into epoxy resin through thermocuring process. The results of thermal experiments showed that silica aerogel/epoxy composite had a lower thermal conductivity (0.105W/(m·k) at 60 wt% silica aerogel) and higher serviceability temperature (Martens heat distortion temperature: 160°C at 20 wt% silica aerogel). In addition, the composite doping larger size (0.2-2mm) of silica aerogel particle had lower thermal conductivity and higher Martens heat distortion temperature. Based on the results of SEM and FT-IR, the thermal transfer model was established. Thermal transfer mechanism and the reasons of higher Martens heat distortion temperature have been discussed respectively.

Measuring the Thermo-Technical Parameters of Autoclaved Aerated Concrete

2016 ◽  
Vol 824 ◽  
pp. 100-107 ◽  
Author(s):  
Alena Struhárová
Keyword(s):  
Thermal Conductivity ◽  
Moisture Content ◽  
Physical Properties ◽  
Bulk Density ◽  
Capillary Absorption ◽  
Measuring Device ◽  
Technical Parameters ◽  
Autoclaved Aerated Concrete ◽  
Aerated Concrete ◽  
Technical Properties

Bulk density and moisture content are factors that significantly affect the physical properties of autoclaved aerated concrete (AAC) including thermal conductivity and other thermo-technical characteristics. This article shows the results of measurements of compressive strength, capillary absorption, water absorption and porosity of AAC (ash on fluidized fly ash) at different bulk density and also the results of thermal conductivity of AAC at different bulk density and variable moisture content of the material. The thermo-technical properties were measured using the Isomet 2104, a portable measuring device. Acquired results demonstrate dependence of physical properties including thermal conductivity of AAC on bulk density and moisture content. The reliability and accuracy of the method of measuring was also shown.

USE OF THE MICROWAVE ENERGY FOR ALUMINUM WASTE FOAMING

2019 ◽  
Vol 25 (4) ◽  
pp. 43-49
Author(s):  
LUCIAN PAUNESCU ◽  
MARIUS FLORIN DRAGOESCU ◽  
SORIN MIRCEA AXINTE ◽  
ANA CASANDRA SEBE
Keyword(s):  
Thermal Conductivity ◽  
Compressive Strength ◽  
Porous Structure ◽  
Powder Mixture ◽  
Aluminum Foam ◽  
Fine Powder ◽  
Microwave Energy ◽  
Raw Material ◽  
Foaming Agent ◽  
Foaming Process

The paper presents an aluminum foam experimental technique using the microwave energy. The raw material was recycling aluminum waste processed by ecological melting and gas atomizing to obtain the fine powder required in the foaming process. The powder mixture was completed with dolomite as a foaming agent. The products had a fine and homogeneous porous structure (pore size between 0.4-0.9 mm). The density (1.17-1.19 g/cm3), the compressive strength (6.83-7.01 MPa) and the thermal conductivity (5.71-5.84 W/m·K) had values almost similar to the foams made by conventional methods.

Cryogenic thermal insulating and mechanical properties of rigid polyurethane foams blown with hydrofluoroolefin: Effect of perfluoroalkane

2021 ◽  
pp. 0021955X2110626
Author(s):  
Tae Seok Kim ◽  
Yeongbeom Lee ◽  
Chul Hyun Hwang ◽  
Kwang Ho Song ◽  
Woo Nyon Kim
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Thermal Stability ◽  
Cell Size ◽  
Thermal Insulation ◽  
Coefficient Of Thermal Expansion ◽  
Lower Surface ◽  
Polyurethane Foams ◽  
Insulation Material ◽  
Pu Foams

The effect of perfluoroalkane (PFA) on the morphology, thermal conductivity, mechanical properties and thermal stability of rigid polyurethane (PU) foams was investigated under ambient and cryogenic conditions. The PU foams were blown with hydrofluorolefin. Morphological results showed that the minimum cell size (153 μm) was observed when the PFA content was 1.0 part per hundred polyols by weight (php). This was due to the lower surface tension of the mixed polyol solution when the PFA content was 1.0 php. The thermal conductivity of PU foams measured under ambient (0.0215 W/mK) and cryogenic (0.0179 W/mK at −100°C) conditions reached a minimum when the PFA content was 1.0 php. The low value of thermal conductivity was a result of the small cell size of the foams. The above results suggest that PFA acted as a nucleating agent to enhanced the thermal insulation properties of PU foams. The compressive and shear strengths of the PU foams did not appreciably change with PFA content at either −170°C or 20°C. However, it shows that the mechanical strengths at −170°C and 20°C for the PU foams meet the specification. Coefficient of thermal expansion, and thermal shock tests of the PU foams showed enough thermal stability for the LNG carrier’s operation temperature. Therefore, it is suggested that the PU foams blown by HFO with the PFA addition can be used as a thermal insulation material for a conventional LNG carrier.

scholarly journals Thermal Performance of Oil Palm Fibre and Paper Pulp as the Insulation Materials

2014 ◽  
Vol 5 (2) ◽  
pp. 22-28
Author(s):  
S.H. Ibrahim ◽  
Sia W.K. ◽  
A. Baharun ◽  
M.N.M. Nawi ◽  
R. Affandi
Keyword(s):  
Thermal Conductivity ◽  
Thermal Performance ◽  
Oil Palm ◽  
Total Density ◽  
Insulation Material ◽  
Paper Pulp ◽  
Particle Board ◽  
Environment Impact ◽  
Palm Fiber ◽  
Insulation Materials

 Energy consumption for residential use in Malaysia is keep increasing yearly in order to maintain the internal thermal comfort of the building. Roof insulation material plays a vital role in improving the thermal comforts of the building while reduce the cooling load of the building. Oil palm industry in Malaysia had grown aggressively over the past few decades. Tons of oil palm waste had produced during the process such as empty fruit bunch fiber. Another waste material that available and easy to obtain is paper. Paper is a valuable material that can be recycled. Waste paper comes from different sources such as newspaper, office and printing papers. This study will take advantage of the available resources which could contribute to reduce the environment impact. The aim of this study is to investigate the thermal performance of roof insulation materials using mixture of oil palm fiber and paper pulp with different ratio and thickness. This study found that the thermal performance of the paper pulp is slightly better compare to the oil palm fiber. Thermal conductivity of the particle board reduces around 4.1% by adding the 10% of paper pulp into the total density of the particle board. By adding 75% of paper pulp, the thermal conductivity of the particle board could be reduced to 24.6% compare to the oil palm fiber board under the similar condition. Therefore, from this study, it could be concluded that paper pulp has high potential to be used as a building insulation material.

scholarly journals Thermal insulation properties of green vacuum insulation panel using wood fiber as core material

BioResources ◽  
2019 ◽  
Vol 14 (2) ◽  
pp. 3339-3351 ◽  
Author(s):  
Baowen Wang ◽  
Zhihui Li ◽  
Xinglai Qi ◽  
Nairong Chen ◽  
Qinzhi Zeng ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Bulk Density ◽  
Thermal Insulation ◽  
Wood Fiber ◽  
Core Material ◽  
High Porosity ◽  
Total Thermal Conductivity ◽  
Wood Fibers ◽  
Vacuum Insulation ◽  
Vacuum Insulation Panel

Wood fibers were prepared as core materials for a vacuum insulation panel (VIP) via a dry molding process. The morphology of the wood fibers and the microstructure, pore structure, transmittance, and thermal conductivity of the wood fiber VIP were tested. The results showed that the wood fibers had excellent thermal insulation properties and formed a porous structure by interweaving with one another. The optimum bulk density that led to a low-cost and highly thermally efficient wood fiber VIP was 180 kg/m3 to 200 kg/m3. The bulk density of the wood fiber VIP was 200 kg/m3, with a high porosity of 78%, a fine pore size of 112.8 μm, and a total pore volume of 7.0 cm3·g-1. The initial total thermal conductivity of the wood fiber VIP was 9.4 mW/(m·K) at 25 °C. The thermal conductivity of the VIP increased with increasing ambient temperature. These results were relatively good compared to the thermal insulation performance of current biomass VIPs, so the use of wood fiber as a VIP core material has broad application prospects.

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