Browsing by Author "Katende, Allan"

Now showing 1 - 8 of 8
  • Thumbnail Image
    Item
    A comprehensive investigation on the performance of durian rind as a lost circulation material in water based drilling mud
    (Petroleum, 2019) Majid, Nor Fatin Fatihah; Katende, Allan; Ismail, Issham; Sagala, Farad; Md Sharif, Norshila; Yunus, Mohd Azizi Che
    Oil and gas operators worldwide are expecting service companies to deliver integrated techniques to minimize, if not prevent, drilling problems. Drilling fluids perform vital functions to ensure the success of drilling operations. The technical challenges often associated with water-based drilling fluids are loss of critical properties, such as fluid loss control and rheology, under demanding conditions, such as in drilling deeper, high-temperature and high-pressure wells. Fluid loss during drilling operations has a very significant effect in both reservoir formation damage and monetary terms. The use of durian rind (DR) as a new additive in controlling lost circulation would provide another opportunity to reduce waste and avoid pollution. Therefore, DR was used to improve the rheological properties of water-based mud, and it was prepared for use as a fluid loss additive. For a better understanding of the influence of pectin on drilling mud properties, the rheological evaluation of untreated DR was compared to that of mud samples containing treated DR. The pectin in DR was extracted using four different solvents, namely, ethanol, methanol, sodium hydroxide and hydrogen peroxide, and the most effective solvent to remove the pectin was then determined. The Fourier transform infrared spectroscopy (FTIR) results showed that NaOH was the best solvent for removing pectin from DR. Thermogravimetric analysis (TGA) was used to determine the thermal stability of DR before and after treatments. The TGA results demonstrated that the treated DR had improved thermal stability compared to untreated DR. The sizes of DR used were coarse, medium, and fine. The untreated DR presented better rheological properties than the treated DR. The experimental investigation showed that a concentration of 20 lb/bbl of intermediate-sized DR was the best concentration among the tested samples.
  • Thumbnail Image
    Item
    A Critical review of Low Salinity Water Flooding: Mechanism, Laboratory and Field Application
    (Journal of Molecular Liquids, 2019) Katende, Allan; Sagala, Farad
    Low-salinity water flooding (LSW) is a promising new technique for enhancing oil recovery (EOR) in both sandstone and carbonate reservoirs. The potential of LSW has drawn the attention of the oil industry in the past decade. Along with the few successful field applications of LSW, various studies in this field in recent years have been conducted mainly at the lab scale. The main objective of this critical review was to investigate the potential of this EOR technique in improving oil recovery and the mechanism under which it operates. As a result, various mechanisms have been proposed. However, no consensus on the dominant mechanism(s) in neither sandstones nor carbonate reservoirs has been reported, and the oil industry is continuing to discover the leading effects. Herein, we provide the chronicle of LSW, analysis of the proposed mechanisms of enhancing oil recovery using LSW in recent findings, some laboratory observations, and finally, some successful field applications. From this review, despite the promising potential justified by both laboratory studies and field applications, there exists a large number of unsuccessful field case studies. LSW is viewed as an immature EOR technique with many ambiguities because definitive conclusions about which mechanism(s) is responsible for improving oil recovery remains elusive and a bewilderment to the oil industry.
  • Thumbnail Image
    Item
    The Effect of WAG Ratio and Oil Density on Oil Recovery by Immiscible Water Alternating Gas Flooding
    (American Journal of Science and Technology, 2017) Anuar, Nur Ain Binti Mohd; Yunan, Mat Hussin; Sagala, Farad; Katende, Allan
    An Enhanced Oil Recovery (EOR) method named Immiscible Water-Alternating-Gas (IWAG) is one of the well-established methods for improving oil recovery in reservoirs. IWAG injection combines both improved displacement efficiency of the gas flooding with an improved macroscopic sweep by water injection. The objective of this study is to investigate the effect of Water-Alternating-Gas (WAG) ratio and oil density on residual oil recovery during IWAG flooding process using dimensions of a real reservoir. A series of six injections were conducted at WAG ratio of 1:1, 1:2, 1:3 and oil densities of 0.72 g/cc, 0.81 g/cc, 0.88 g/cc with flow rate of 1 cc/min for every injection. In this study, a secondary recovery method, which is water-flooding, had been conducted first and continued with immiscible gas-flooding before the start of IWAG to determine the overall recovery factor that can be increased with the utilization of IWAG as an EOR tertiary method. Water flooding had resulted in good oil recovery, which was about 36%–50% Oil Initially In Place (OIIP). Meanwhile immiscible gas-flooding had resulted in only 1% –3% OIIP. The results showed that a WAG ratio of 1:1 was the optimal ratio since the tertiary oil recovery using IWAG was 8% and total 45% of OIIP whereas oil density of 0.72 g/cc was the optimal density which gave 9% of oil recovery using IWAG and total 64% of OIIP. The experimental outcome additionally demonstrated that the IWAG method becomes more efficient in equal water and gas slug ratio which is favourable for low oil density. This is because water and gas help in both microscopic and macroscopic sweep efficiency whereas the mobility of low oil density is higher and flows with low resistance.
  • Thumbnail Image
    Item
    Experimental Investigation of Cuttings Lifting Efficiency Using Low and High Density Polyethylene Beads in Different Hole Angles
    (J Mater Sci Appl, 2017) Tan, Tin Yi; Katende, Allan; Sagala, Farad; Mugisa, John
    This study investigates the impact of low and high density polyethylene beads on wellbore cleaning using water-based mud at different hole angles of 0°, 60°, and 90°. The polyethylene beads concertation is varied from 1 to 5% by volume. Experimental investigations were accomplished using 11ft long acrylic concentric annulus flow test section with a 1.80in casing inner diameter equipped with a fixed inner pipe of 0.85in as the outer diameter. A total of 66 runs were completed using sand of size ranging from 1.18 – 2.00mm and density of 2.65 g/cc. Mud density and viscosity were maintained at 10 ppg and 7cp respectively, in a flow velocity of 0.80m/s. The densities of low and high density polyethylene beads were 0.92 g/cc and 0.96 g/cc respectively while their size was 3mm in spherical shape. The introduction of polyethylene beads were found to be more efficient in the vertical hole in which the incremental cuttings transport ratio was more than 15% being registered. This was due to sufficient buoyancy force provided by the low density polyethylene beads to counteract the gravity force and reduce the slip velocity of cuttings due to their low densities. In addition, the impulsive force due to collision between beads and sand enabled the cuttings to be lifted more efficiently.
  • Thumbnail Image
    Item
    Experimental Investigation of the Effect of Drill Pipe Rotation on Improving Hole Cleaning using Water-based Mud Enriched with Polypropylene Beads in Vertical and Horizontal Wellbores
    (Journal of Petroleum Science and Engineering, 2019) Heshamudin, Nursyafiqah S.; Katende, Allan; Rashid, Halimatun A.; Ismail, Issham; Sagala, Farad; Samsuri, Ariffin
    Field experience has shown that the inefficient transport of small cuttings is a main factor contributing to excessive drag and torque during the drilling of a deviated hole; however, very little is known about the transport behavior of small cuttings. This experimental study investigates the effect of different polypropylene bead concentrations in water-based mud (WBM) on hole cleaning, along with the effects of cutting size, drill pipe rotation, and hole inclination angle. A total of 160 runs were performed using an experimental rig consisting of a 13 ft (3.96 m) long casing with a 2 in (50.8 mm) Inner Diameter (ID) and a rotary inner pipe with a 0.8 in (20 mm) Outer Diameter (OD). Four cutting size ranges, namely, 0.5–1.0 mm, 1.0–1.4 mm, 1.4–1.7 mm, and 1.7–2.0 mm, with a density of 2400 kg/ were tested in WBM with varying polypropylene bead concentrations ranging from 0 to 8 ppb. The concentric annulus flow test section was changed to vertical and horizontal angles with pipe rotation from 0 to 150 rpm. The mud density and viscosity were maintained at 10 ppg and 16 cp, respectively, under a flow velocity of 3.48 m/s (Reynolds number of 6620). The results indicate that smaller cuttings are easier to transport at all pipe rotations and polypropylene bead concentrations in both vertical and horizontal holes. The optimal pipe rotational speed was found to be 60 rpm. In this study, polypropylene beads undeniably enhanced the mud carrying capacity by significantly increasing the cutting transport ratio (CTR) by up to 16.57% in vertical holes and 15.73% in horizontal holes.
  • Thumbnail Image
    Item
    Improving Hole Cleaning using Low Density Polyethylene Beads at Different Mud Circulation Rates in Different Hole Angles
    (Journal of Natural Gas Science and Engineering, 2019) Yeu, Wong Jenn; Katende, Allan; Sagala, Farad; Ismail, Issham
    In oil and gas exploration and development, drilling a hole is one of the first and most expensive operations. The continuous demand from industry to reduce costs and operational problems has resulted in numerous innovative drilling technologies that allow us to drill directionally. Nevertheless, hole cleaning has become a problematic issue in directional drilling because drill cuttings tend to be deposited on the lower side of the deviated hole. Excess accumulation of cuttings significantly reduces the rate of penetration and indirectly increases the operational cost. To improve the cuttings transport efficiency in a deviated hole, low-density polyethylene (LDPE) beads were introduced into water-based mud for hole cleaning. LDPE beads travel rapidly through the mud column due to buoyancy and move the cuttings forward by drag and collision. The interaction between the LDPE beads and cuttings facilitates the cuttings transport process and prevents the cuttings from settling. In this study, different concentrations of LDPE beads (i.e., 1% to 5% by volume) and different flow rates (i.e., 0.4 L/s, 0.6 L/s, and 1.0 L/s) were used to determine the effects on cuttings transport efficiency. In addition, the hole angle was varied from vertical to horizontal to evaluate the significance of LDPE beads in assisting in transporting cuttings. The results denote that more cuttings can be removed from a hole with higher concentrations of LDPE beads in water-based mud. This finding is due to the higher frequency of collisions, which in turn produces larger impulsive force. In addition, the improvement in cuttings transport efficiency enabled by LDPE beads is more significant in a vertical hole than in a highly deviated hole. In summary, LDPE beads are a promising additive for drilling mud to effectively remove drilled cuttings from a hole.
  • Thumbnail Image
    Item
    Improving the Performance of Oil Based Mud and Water Based Mud in a High Temperature Hole using Nanosilica Nanoparticles
    (Colloids and surfaces A: physicochemical and engineering aspects, 2019) Katende, Allan; Sagala, Farad; Norhafizuddin, Hussein; Ismail, Muhamad S.
    Oil-based mud (OBM), a non-Newtonian fluid, is known for its superior performance in drilling complex wells as well as combating potential drilling complications. However, the good performance may degrade under certain circumstances especially because of the impact of chemical instability at an elevated temperature. The same phenomenon occurs for water-based mud (WBM) when it is used in drilling under high temperature conditions. To prevent this degradation from occurring, numerous studies on utilizing nanoparticles to formulate smart fluids for drilling operations are being conducted worldwide. Hence, this study aims to evaluate the performance of nanosilica (NS) as a fluid loss reducer and a rheological property improver in both OBM and WBM systems at high temperature conditions. This study focuses on the impacts of different nanosilica concentrations, varying from 0.5 ppb to 1.5 ppb, and different mud weights of 9 ppg and 12 pg as well as different aging temperatures, ranging from ambient temperature to 300 °F, on the rheological performance of OBM and WBM. All the rheological properties are measured at ambient temperature, and additionally tests, including lubricity, electrical stability, and high-pressure high-temperature filtration measurements, are conducted, and rheological models are obtained. The performance of nanosilica is then studied by comparing each of the nanosilica-enhanced mud systems with the corresponding basic mud system, taking the fluid loss and rheological properties as the benchmark parameters. Nanosilica shows a positive impact on OBM and WBM, as the presence of nanosilica in the mud systems can effectively improve almost all their rheological properties.
  • Thumbnail Image
    Item
    Performance of Polyethylene and Polypropylene Beads towards Drill Cuttings Transportation in Horizontal Wellbore
    (Journal of Petroleum Science and Engineering, 2018) Hakim, Hadyan; Katende, Allan; Sagala, Farad; Ismail, Issham; Nsamba, Hussein
    Drilled cuttings removal is critical in drilling operations, especially in horizontal wells. These cuttings are postulated to be among the possible causes of many costly complications, such as mechanical pipe sticking, bore hole instability, drag and torque. This study proposes a new approach that uses polymer beads as a mud additive to improve cutting transportation. In this study, the effect of the concentration of polyethylene (PE) and polypropylene (PP) polymer beads on cuttings transport efficiency (CTE) in water-based mud in a horizontal wellbore was investigated. Experiments were conducted in a lab-scale flow loop equipped with a 13-ft (3.96 m) test section consisting of a concentric annulus acrylic outer casing (2 in. ID) and a static inner PVC drill string (0.79 in. OD). A total of 150 tests were conducted using 10 ppg water based mud (WBM) with 1%–5% by vol. Concentrations of polymer beads (PE and PP) were added at a range of 8–9.5 cp. Six different sizes of drilled cuttings ranging from 0.5 to 4.0 mm were used as samples to determine the CTE at a constant 0.69 m/s average annular fluid velocity. The results revealed that CTE increased with the increase of polymer bead concentrations and that PP is better compared to PE overall due to its low density. The highest CTE was recorded at a 5% concentration of water-based mud polypropylene (WBMPP), which is approximately 96% for cutting sizes of 0.50mm–0.99 mm.