In recent years, the search for economic and environmentally friendly alternatives has become a global necessity to achieve sustainability and preserve raw materials. From this concept, natural bitumen (NB) derived from sulphur springs is now one of the most promising alternative energy resources for many applications, especially in asphalt pavement construction. Its low price and abundance characterise NB since sulphur springs produce thousands of tonnes of NB annually and are used in very limited fields. Two main objectives were adopted for this work. The first objective is to examine the virgin NB properties from five sulphur springs and compare them with petroleum asphalt. The second objective is to enhance NB properties by applying heat treatment. The experimental results reveal that heat treatment is highly effective in improving the NB properties. This was confirmed by conducting many tests, such as asphalt, Marshall, SEM-EDX, and indirect tensile strength tests. Based on the experimental test outcomes, virgin NB properties do not conform to asphalt specification limits and are unsuitable for flexible roads. Also, MS-NB significantly affected the mechanical properties of the asphalt mixture, as Marshall's stability increased by 41.3% compared to the conventional mixture. In addition, SS-NB was more effective in moisture damage resistance due to increasing the tensile strength ratio by 5.72 % and provided a higher stiffness index than the conventional mixture by 40.36%. In conclusion, the treated NB can successfully be used as a binder material in hot asphalt mixtures. ABSTRAK: Beberapa tahun kebelakangan, pencarian alternatif baharu ekonomi dan mesra alam telah menjadi satu keperluan global bagi mencapai kemampanan dan memelihara bahan mentah. Melalui konsep ini, bitumen asli (NB) yang diperoleh daripada mata air sulfur kini merupakan satu sumber tenaga alternatif yang berguna bagi digunakan dalam pelbagai aplikasi, terutamanya dalam pembinaan turapan asfalt. NB dicirikan oleh harga yang rendah dan kelimpahannya kerana mata air sulfur menghasilkan beribu-ribu tan NB setiap tahun dan digunakan dalam bidang terhad. Dua objektif utama telah dipakai untuk kajian ini. Objektif pertama adalah memeriksa sifat NB dara daripada lima mata air sulfur dan membandingkannya dengan asfalt petroleum. Objektif kedua adalah meningkatkan sifat NB dengan menggunakan rawatan haba. Dapatan eksperimen mendedahkan bahawa rawatan haba sangat berkesan dalam meningkatkan sifat NB. Ini disahkan dengan menjalankan pelbagai ujian, seperti ujian asfalt, ujian Marshall, ujian SEM-EDX, dan ujian kekuatan tegangan tidak langsung. Berdasarkan dapatan eksperimen, sifat NB dara tidak mematuhi had spesifikasi asfalt dan tidak sesuai untuk jalan fleksibel. Selain itu, MS-NB mempunyai kesan ketara pada sifat mekanikal campuran asfalt kerana kestabilan Marshalls meningkat sebanyak 41.3% berbanding campuran konvensional. Tambahan, SS-NB lebih berkesan dalam rintangan kerosakan lembapan kerana meningkatkan nisbah kekuatan tegangan sebanyak 5.72 % dan memberikan indeks kekukuhan yang lebih tinggi daripada campuran konvensional sebanyak 40.36%. Kesimpulannya, NB yang dirawat boleh berjaya digunakan sebagai bahan pengikat dalam campuran asfalt panas.
Experiments were carried out to investigate natural convection heat transfer in an inclined uniformly heated circular cylinder . The effects of surface heat flux and angle of inclination on the temperature and local Nusselt number variations along the cylinder surface are discussed . The investigation covers heat flux range from 92 W/m² to 487 W/m², and angles of inclination 0° ( horizontal) , 30° , 60° and 90° (vertical) . Results show an increase in the natural convection as heat flux increases and as angle of inclination moves from vertical to horizontal position. An empirical equation of average Nusselt number as a function of Rayliegh number was deduced for each angle of inclination .
Recently a large number of extensive studies have amassed that describe the removal of dyes from water and wastewater using natural adsorbents and modified materials. Methyl orange dye is found in wastewater streams from various industries that include textiles, plastics, printing and paper among other sources. This article reviews methyl orange adsorption onto natural and modified materials. Despite many techniques available, adsorption stands out for efficient water and wastewater treatment for its ease of operation, flexibility and large-scale removal of colorants. It also has a significant potential for regeneration recovery and recycling of adsorbents in comparison to other water treatment methods. The adsorbents described herein were
... Show MoreWater scarcity is one of the most important problems facing humanity in various fields such as economics, industry, agriculture, and tourism. This may push people to use low-quality water like industrial-wastewater. The application of some chemical compounds to get rid of heavy metals such as cadmium is an environmentally harmful approach. It is well-known that heavy metals as cadmium may induce harmful problems when present in water and invade to soil, plants and food chain of a human being. In this case, man will be forced to use the low quality water in irrigation. Application of natural materials instead of chemicals to remove cadmium from polluted water is an environmental friendly approach. Attention was drawn in this research wor
... Show MoreFrequently, Load associated mode of failure (rutting and fatigue) as well as, occasionally, moisture damage in some sections poorly drained are the main failure types found in some of the newly constructed road within Baghdad as well as other cities in Iraq. The use of hydrated lime in pavement construction could be one of the possible steps taken in the direction of improving pavement performance and meeting the required standards. In this study, the mechanistic properties of asphalt concrete mixes modified with hydrated lime as a partial replacement of limestone dust mineral filler were evaluated. Seven replacement rates were used; 0, 0.5, 1, 1.5, 2, 2.5 and 3 percent by weight of aggregate. Asphalt concrete mixes were prepared at their
... Show MoreNatural dye sensitized solar cell was prepared using strawberry and pomegranate dyes with anatase nanocrystalline titanium dioxide powder. A study of the optical properties of the two dyes, involving the absorption spectrum was determined in the visible region. I-V characteristics under illumination were performed. The results showed that the two prepared dye sensitized solar cells have acceptable values efficiency about (0.94 with Fill factor (45)) and (0.74 with Fill factor (44)) for strawberry and pomegranate dyes, respectively.
In this study, the turbulent buoyancy driven fluid flow and heat transfer in a differentially heated rectangular enclosure filled with water is quantified numerically. The two dimensional governing differential equations are discretized using the finite volume method. SIMPLE algorithm is employed to obtain stabilized solution for high Rayleigh numbers by a computational code written in FORTRAN language. A parametric study is undertaken and the effect of Rayleigh numbers (1010 to 1014), the aspect ratio (30, 40 and 50), and the tilt angle (10o to 170o ) on fluid flow and heat transfer are investigated. The results of the adopted model in the present work is compared with previously published results and a qualitative agreement and a good
... Show MoreFrequently, Load associated mode of failure (rutting and fatigue) as well as, occasionally, moisture damage in some sections poorly drained are the main failure types found in some of the newly constructed road within Baghdad as well as other cities in Iraq. The use of hydrated lime in pavement construction could be one of the possible steps taken in the direction of improving pavement performance and meeting the required standards. In this study, the mechanistic properties of asphalt concrete mixes modified with hydrated lime as a partial replacement of limestone dust mineral filler were evaluated. Seven replacement rates were used; 0,0.5, 1, 1.5, 2, 2.5 and 3 percent by weight of aggregate. Asphalt concrete mixes were prepared at their
... Show MoreWarm mix asphalt (WMA) is relatively a new technology which enables the production and compaction of asphalt concrete mixtures at temperatures 15-40 °C lower than that of traditional hot mix asphalt HMA. In the present work, six asphalt concrete mixtures were produced in the mix plant (1 ton each) in six different batches. Half of these mixes were WMA and the other half were HMA. Three types of fillers (limestone dust, Portland cement and hydrated lime) were used for each type of mix. Samples were then taken from these patches and transferred to lab for performance testing which includes: Marshall characteristics, moisture susceptibility (indirect tension test), resilient modulus, permanent deformation (axial repeated load test)
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