Study on Strength & Durability of Concrete by Partial Replacement of Fine & Coarse Aggregates using Marble, Granite & Spent Fire Brick Waste
Concrete is the most undisputable and indispensable material being used in infrastructure development throughout the world. The objective of this paper is to utilize marble, granite and Spent Fire Brick waste of different sizes in the manufacturing of concrete bricks, with partial replacement of conventional coarse and fine aggregates with Marble, Granite and Spent Fire Brick waste content up to 20%.The produced bricks are tested for physical and mechanical properties according to the requirements of the American Standards for Testing Materials (ASTM) and the INDIAN Code. The test results revealed that the recycled products have physical and mechanical properties that qualify them for use in the building sector.
Geological and technical characterisation of Iscehisar (Afyon-Turkey) marble deposits and the impact of marble waste on environmental pollution.
Turkey, due to its location in the Alpine-Himalayan belt, has numerous marble deposits. More than 250 marble types with different colours and patterns have been produced from these deposits and one hundred of these are well known around the world. One such well-known marble type is Afyon-Iscehisar. Afyon-Iscehisar is Palaeozoic in age and has been quarried since the era of the Roman empire. The Afyon region is known as one of the most important marble production and processing centres in Turkey. The Afyon province, which possesses 3.5% of exploitable marble reserves (3,872,000,000 tonne) in Turkey, yields 9% of the total marble block production. The 409 marble processing plants in Afyon produce 19% of the total slab in Turkey. As a result of marble production activities, approximately 340,000 tonne of marble waste has accumulated in the area. While some of these unshaped marble blocks are re-used and returned to the economy, the majority are discarded. There are two waste marble storage fields located in the Afyon-Iscehisar region. All of the solid and fine-grained marble waste is stored in waste marble storage fields in Susuz Boğazi and in the nearby Iscehisar marble quarries. The ecological effects of the marble waste, which were once discharged everywhere and exhibited visual pollution, has now been reduced to a minimal level.
Prevention of Barite Sag in Oil-Based Drilling Fluids Using a Mixture of Barite and Ilmenite as Weighting Material
Drilling high-pressure high-temperature (HPHT) wells requires a special fluid formulation that is capable of controlling the high pressure and is stable under the high downhole temperature. Barite-weighted fluids are common for such purpose because of the good properties of barite, its low cost, and its availability. However, solids settlement is a major problem encountered with this type of fluids, especially at elevated downhole temperatures. This phenomenon is known as barite sag, and it is encountered in vertical and directional wells under static or dynamic conditions leading to serious well control issues. This study aims to evaluate the use of barite-ilmenite mixture as a weighting agent to prevent solids sag in oil-based muds at elevated temperatures. Sag test was conducted under static conditions (vertical and inclined) at 350 °F and under dynamic conditions at 120 °F to determine the optimum ilmenite concentration. Afterward, a complete evaluation of the drilling fluid was performed by monitoring density, electrical stability, rheological and viscoelastic properties, and filtration performance to study the impact of adding ilmenite on drilling fluid performance. The results of this study showed that adding ilmenite reduces sag tendency, and only 40 wt.% ilmenite (from the total weighting material) was adequate to eliminate barite sag under both static and dynamic conditions with a sag factor of around 0.51. Adding ilmenite enhanced the rheological and viscoelastic properties and the suspension of solid particles in the drilling fluid, which confirmed sag test results. Adding ilmenite slightly increased the density of the drilling fluid, with a slight decrease in the electrical stability within the acceptable range of field applications. Moreover, a minor improvement in the filtration performance of the drilling fluid and filter cake sealing properties was observed with the combined weighting agent. The findings of this study provide a practical solution to the barite sag issue in oil-based fluids using a combination of barite and ilmenite powder as a weighting agent to drill HPHT oil and gas wells safely and efficiently with such type of fluids.