Akademik Veri Yönetim Sistemi
Tezin Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Petrol ve Doğal Gaz Mühendisliği Bölümü, Türkiye
Tezin Onay Tarihi: 2014
Öğrenci: ÖZGE RAMAZANOĞLU
Eş Danışman: SERHAT AKIN, İSMAİL ÖZGÜR YAMAN
Özet:In the petroleum industry, oil well cements are used in the form of slurries during the construction of oil or natural gas wells. Preserving the integrity of the well and the casing, providing zonal isolation are some of the uses of these special cements. Oil well cement slurries used in the petroleum industry are subjected to different exposure conditions than ordinary Portland cement slurries used in the construction industry. Therefore, oil well cements are required to possess different engineering properties than ordinary Portland cements. During their usage, these cements often interact with various chloride sources either from the water that is being used in the preparation of the slurries, or sometimes intentionally used as an additive to achieve required properties. Therefore, there is a need to identify the effects of chlorides from different sources on the properties of oil well cements. This study presents an experimental program that investigates the effects of different chloride sources on the properties of slurries prepared by class G cement. In the experimental program, a total of 22 cement slurries containing KCl, CaCl2 and NaCl at various amounts are prepared. A control cement slurry with no salt addition is used as a reference. Cement slurries used in all experiments are prepared with the same water/cement ratio (0.44) as stated for Class G cement in API Specification 10A. The experiments that are carried out according to API Spec 10A for the conditions of medium depth oil wells include free fluid content, thickening time, compressive strength and rheology of cement slurries. As a result of the experimental program, it was observed that different chloride sources have different effects on cement slurries’ properties. The effect of salt concentration is very clear on thickening time, compressive strength and rheological properties when compared with the free fluid properties. It is seen that, CaCl2 is the most effective accelerator when compared to other chloride sources. However, when used in higher amounts, it negatively affects the flow properties of the slurries. NaCl is also an effective accelerator when used in lower amounts. On the other hand, when used in higher amounts it rather works as a retarder. KCl, on the other hand, works rather as a dispersant to improve the flow properties of the slurries. The optimum amount depends on the cement properties.