Limestone dust | ScienceGate

This article presents the results of tests of mastic containing mixed filler (limestone dust/hydrated lime) and Fisher-Tropsch synthetic wax. Synthetic wax content was controlled up to 3% (w/w). The ratio of filler in the bitumen was from 0.5 to 3 (w/w), with hydrated lime content of up to 30% w/w. The rheological properties of different mastic compositions were determined with a rheometer equipped with two parallel plates at 60°C using oscillating load. The primary purpose of the article was to determine the nature of mastic stiffness changes in the context of using hydrated lime and synthetic wax as the filler. Consequently, the article proposes a method for evaluation of the critical value of the filler phase in the phase of bitumen modified with synthetic wax. The proposed model of the mathematical function was used to determine the nature of mastic structuring throughout the range of the experiment. The model was also used to determine the critical concentration of the filler in the bitumen phase. It was demonstrated that below the critical filler concentration the mastic behaved in a significantly different manner from the behaviour observed above this critical concentration. When the critical concentration of the filler was exceeded, it resulted in an excessive increase of mastic stiffness, which was considered in the model.

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CHARACTERISTICS OF AEROSOLS IN BEIJING-TIANJIN AREA OF CHINA BY PIXE AND INAA AND IDENTIFICATION OF THEIR SOURCES BY CEB

International Journal of PIXE ◽

10.1142/s0129083592000634 ◽

1992 ◽

Vol 02 (04) ◽

pp. 593-601 ◽

Cited By ~ 6

Author(s):

Sha Yin ◽

Liu Pingsheng ◽

Hu Zhaohui ◽

Zhong Ming ◽

Yang Shaojin ◽

...

Keyword(s):

Coal Combustion ◽

Fine Particles ◽

Motor Vehicle ◽

Chemical Elements ◽

Sea Salt ◽

Soil Dust ◽

Air Filter ◽

X Ray ◽

Sea Salt Aerosol ◽

Limestone Dust

Proton Induced X-ray Emission (PIXE) and Instrumental Neutron Activation Analysis (INAA) techniques were used to measure the contents of 45 elements in 150 air-filter samples collected by cascade impactor with 8 stages at 10 sites in Beijing-Tianjin area of China during the periods of the winter of 1983 and the summer of 1984. It was noticed that the toxic elements such as As, Sb, Se, Pb, Hg, Cu and Ni were mainly enriched in fine particles with diameter less than 2 um. The major seven sources of coal burning, soil dust, oi1 burning, sea-salt aerosol, motor vehicle emission, limestone dust and industrial refuse attributing to the pollution in Tianjin area were identified by Chemical Elements Balance method (CEB). Among them the most important sources were the soil dust and the emission from coal-combustion followed by contributions from limestone and industrial refuse.

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Oil-Sludge Extended Asphalt Mastic Filled with Heavy Oil Fly Ash and Cement Waste for Waterproofing

The Journal of Engineering Research [TJER] ◽

10.24200/tjer.vol11iss2pp27-38 ◽

2014 ◽

Vol 11 (2) ◽

pp. 27

Author(s):

H.I. Al-Abdul Wahhab ◽

M.A. Dalhat

Keyword(s):

Fly Ash ◽

Heavy Oil ◽

Oil Sludge ◽

Cement Kiln ◽

Strength Deterioration ◽

Asphalt Mastic ◽

And Performance ◽

American Society ◽

Oil Fly Ash ◽

Limestone Dust

Recycling as an economic disposal process for many hazardous waste materials has become a popular means of conserving our planet’s scarce and diminishing natural resources. This paper is a study of the influence of oil sludge (OS) on the physical behavior and performance of asphalt filled with heavy oil fly ash (HOFA), cement kiln dust (CKD) and limestone dust (LMD). Conventional asphalt consistency tests in addition to a new bond strength (BS) test were conducted on the modified asphalt mastics. The results were statistically analyzed and assessed in accordance with American Society for Testing and Materials (ASTM) D 332 and ASTM D 449 specifications. Too much OS resulted in strength deterioration of the asphalt mastic, which can be compensated for by filling the mastic with HOFA. OS interacts constructively with the fillers to improve their effectiveness in raising the softening point (SP) and viscosity of the asphalt, and also in reducing its penetration and ductility. Even though sludge mastics hold promise as suitable composites for damp proofing and waterproofing, the resulting low flash point (FP) and SP of some of these mastics make their suitability for roofing applications questionable.

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