Effect of natural pozzolan on the fresh and hardened cement slurry properties for cementing oil well

2018 ◽  
Vol 15 (4) ◽  
pp. 513-519 ◽  
Author(s):  
Somia Bechar ◽  
Djamal Zerrouki

PurposeWells’ cementing is an important and costly step in the engineering sector for oil and gas well. The purpose of this study was to investigate the use of Algerian natural pozzolan (NP) in order to evaluate the influence of partial substitution of class G cement on slurry properties.Design/methodology/approachNP was characterized by X-ray fluorescence (XRF), scanning electron microscopy/energy-dispersive X-ray (SEM/EDX) and Fourier-transform infra-red spectrometry (FTIR). Their pozzolanic activity was evaluated by measuring the electrical conductivity in aqueous suspensions of pozzolan/calcium hydroxide. The replacement ration cement/NP was 10, 20 and 30 per cent, and the rheological behaviour, compressive strength properties at different ages, elastic properties, X-ray diffraction analysis, rapid chloride penetration, porosity and permeability of all slurries were investigated and compared with a standard sample.FindingsThe obtained results indicated that the replacement with 20 per cent by weight of cement at 21 and 28 days had a higher compressive strength (+30.62 per cent) and lower chloride penetration.Originality/valueThe results show the potential of the use of locally available NP in well cementing.

2021 ◽  
pp. 147-156
Author(s):  
Ali M. Hadi ◽  
Ayad A. Al-Haleem

Cement is a major component in oil and gas drilling operations that is used to maintain the integrity of boreholes by preventing the movement of formation fluids through the annular space and outside the casing. In 2019, Iraq National Oil Company ordered all international oil and gas companies which are working in Iraq to use Iraqi cement (made in Iraq) in all Iraqi oil fields; however, the X-ray fluorescence (XRF) and compressive strength results in this study show that this cement is not matching with American Petroleum Institute (API) standards. During this study, barolift was used to improve the properties of Iraqi cement used in oil wells at high pressure and high temperature (HPHT). Barolift (1 g) was added to cement admixture to evaluate its influence on improving the performance of cement, mainly related to the property of toughness.  Primarily, the quality and quantity of cement contents were determined using X-ray fluorescence. Experiments were conducted to examine the characteristics of the base cement and the cement system containing 1g of barolift, such as thickening time, free water, compressive strength, and porosity. X-ray diffraction (XRD), scanning electron microscope (SEM), and energy dispersive X-ray spectroscopy (EDS) were conducted for analyzing the microstructure of cement powder. The experimental results showed that barolift acted as a retarder and improved the thickening time, slightly increased the free water, enhanced the mechanical properties, reduced the porosity, and aided in scheming new cement slurry to withstand the HPHT conditions. Microstructure analysis showed that barolift particles blocked the capillaries by filling cement spaces and, thus, a denser and stricter cement network was achieved.


2014 ◽  
Vol 692 ◽  
pp. 433-438 ◽  
Author(s):  
Jing Fu Zhang ◽  
Jin Long Yang ◽  
Kai Liu ◽  
Bo Wang ◽  
Rui Xue Hou

Carbon dioxide CO2could corrode the oil well cement paste matrix under agreeable moisture and pressure condition in deep oil wells, which could decrease the compressive strength and damage the annular seal reliability of cement paste matrix. The problem of oil well cement paste matrix corrosion by CO2was researched in the paper for obtain the feasible corrosion prevention technical measures. The microstructure and compressive strength of corroded cement paste matrix were examined by scanning electron microscopeSEMand strength test instrument etc. under different corrosion conditions. The mechanism and effect law of corrosion on oil well cement paste matrix by CO2were analyzed. And the suitable method to protect CO2corrosion in deep oil wells was explored. The results show that the corrosion mechanism of cement paste matrix by CO2was that the wetting phase CO2could generate chemical reaction with original hydration products produced from cement hydration, which CaCO3were developed and the original composition and microstructure of cement paste matrix were destroyed. The compressive strength of corrosion cement paste matrix always was lower than that of un-corrosion cement paste matrix. The compressive strength of corrosion cement paste matrix decreased with increase of curing temperature and differential pressure. The corroded degree of cement paste matrix was intimately related with the compositions of cement slurry. Developing and design anti-corrosive cement slurry should base on effectively improving the compact degree and original strength of cement paste matrix. The compounding additive R designed in the paper could effectively improve the anti-corrosive ability of cement slurry.


2012 ◽  
Vol 730-732 ◽  
pp. 307-312 ◽  
Author(s):  
Ana Cecilia Vieira da Nóbrega ◽  
Antonio Eduardo Martinelli ◽  
Dulce Maria de Araújo Melo ◽  
Marcus Antonio de Freitas Melo ◽  
Julio Cezar de Oliveira Freitas ◽  
...  

Mud acid attack of 14 lbm/gal Portland cement composites with 15 % of nonionic aqueous polyurethane was investigated. Plain Portland hardened cement slurries showed the loss of weight around 23 %. The addition of aqueous polyurethane resulted in longer durability, with reduction around 87 % on the loss of weight without influence on the compressive strength or fratographic. The mechanism is related with the decreased porosity and permeability due to the polymeric net formation on the bulk and minor quantities of Ca+2, preferentially leached to the acidic solution. In this way, Portland-aqueous polyurethane composites are possible solutions to oil well cementing submitted to steam injection and mud acid acidizing operations.


2021 ◽  
Vol 22 (1) ◽  
pp. 1-13
Author(s):  
Amel Habeeb Assi ◽  
Faleh H.M. Almehdawi

This effort is related to describe and assess the performance of the Iraqi cement sample planned for oil well-cementing jobs in Iraq. In this paper, major cementing properties which are thickening time, compressive strength, and free water in addition to the rheological properties and filtration of cement slurry underneath definite circumstances are experimentally tested. The consequences point to that the Iraqi cement after special additives encounter the requests of the API standards and can consequently is used in cementing jobs for oil wells. At this research, there is a comparative investigation established on experimental work on the effectiveness of some additives that considered as waste materials which are silica fume, bauxite, and glass powder, and other conventional additives which are: (SCR -100 Retarder, HR-5, FWCA, Hollow Glass Spheres (HGS) and Halad-9) that currently used in our fields on local Iraqi cement and putting foreign cement results as a governor. Chemical analysis for Iraqi cement, imported cement, and waste materials samples was determined using the X-ray fluorescence (XRF) technique and found minor differences in composition between those samples and depending on the results of X-ray, we selecting the appropriate additives to prepare cement slurry samples. The X-ray fluorescence (XRF) results show that Iraqi Cement has a low value of silica which is about 18.63% while Omani cement about 37.58%. This research examined the potential of micro silica, bauxite, and waste glass powder to produce sustainable cement slurry. The results showed that adding micro silica and bauxite enhances the performance of Iraqi cement but also leads to a slight decrease in thickening time. To avoid this problem, Superplasticizer is used to make the process of cement pumping more easily, in other words, increase thickening time and increase compressive strength. Furthermore, adding glass powder increase the value of compressive strength. Both additives (waste and conventional) are used for the slurry design for achieving better slurry properties, but waste additives increase and enhance Iraqi cement performance than conventional additives, in other words, making it more effective than commercial cement. Depending on the results of the compressive strength test, the optimal concentration of the waste materials used in this research was found, and then the optimal concentration was used to prepare cement samples. The results showed that the use of waste materials to prepare cement slurry is a promising way to improve the efficiency of cement work and to reduce the negative environmental impact resulting from the industry. The results of the program CemCADE proved to be the sample A and C showed good performance through high cement bonding and ideal distribution of fluids designed to accomplish the cementing process.


2019 ◽  
Vol 11 (23) ◽  
pp. 6776 ◽  
Author(s):  
Abdulmalek Ahmed ◽  
Ahmed Abdulhamid Mahmoud ◽  
Salaheldin Elkatatny ◽  
Weiqing Chen

In deep hydrocarbon development wells, cement slurry with high density is required to effectively balance the high-pressure formations. The increase in the slurry density could be achieved by adding different heavy materials. In this study, the effect of the weighting materials (barite, hematite, and ilmenite) on the properties of Saudi Class G cement matrix of vertical homogeneity, compressive strength, porosity, and permeability was evaluated. Three cement slurries were weighted with barite, hematite, and ilmenite, and cured at 294 °F and 3000 psi for 24 h. All slurries have the same concentration of the different additives except the weighting material. The amount of weighting material used in every slurry was determined based on the targeted density of 18 lbm/gal. The results of this study revealed that the most vertically homogenous cement matrix was the ilmenite-weighted sample with a vertical variation of 17.6% compared to 20.2 and 24.8% for hematite- and barite-weighted cement, respectively. This is attributed to the small particle size of the ilmenite. The medical computerized tomography (CT) scan confirmed that the ilmenite-weighted sample is the most homogeneous, with a narrow range of density variation vertically along the sample. Hematite-weighted cement showed the highest compressive strength of 55.3 MPa, and the barite- and ilmenite-weighted cement compressive strengths are each 18.4 and 36.7% less than the compressive strength of the hematite-weighted cement, respectively. Barite-weighted cement has the lowest porosity and permeability of 6.1% and 18.9 mD, respectively. The maximum particle size of ilmenite used in this study is less than 42 μm to ensure no abrasion effect on the drilling system, and it minimized the solids segregation while maintaining a compressive strength that is higher than the minimum acceptable strength, which is the recommended weighting material for Saudi Class G cement.


2019 ◽  
Vol 10 (2) ◽  
pp. 319-325
Author(s):  
Ghulam Abbas ◽  
Sonny Irawan ◽  
Khalil Rehman Memon ◽  
Javed Khan

AbstractCellulose-based polymers have been successfully used in many areas of petroleum engineering especially in enhanced oil recovery drilling fluid, fracturing and cementing. This paper presents the application of cellulose-based polymer in oil well cementing. These polymers work as multifunctional additive in cement slurry that reduce the quantity of additives and lessen the operational cost of cementing operation. The viscosity of cellulose polymers such as hydroxyethyl cellulose (HEC), carboxymethylcellulose (CMC) and hydroxypropyl methylcellulose (HPMC) has been determined at various temperatures to evaluate the thermal degradation. Moreover, polymers are incorporated in cement slurry to evaluate the properties and affect in cement slurry at 90 °C. The API properties like rheology, free water separation, fluid loss and compressive strength of slurries with and without polymer have been determined at 90 °C. The experimental results showed that the viscosity of HPMC polymer was enhanced at 90 °C than other cellulose-based polymers. The comparative and experimental analyses showed that the implementation of cellulose-based polymers improves the API properties of cement slurry at 90 °C. The increased viscosity of these polymers showed high rheology that was adjusted by adding dispersant which optimizes the rheology of slurry. Further, improved API properties, i.e., zero free water separation, none sedimentation, less than 50 ml/30 min fluid loss and high compressive strength, were obtained through HEC, CMC and HPMC polymer. It is concluded that cellulose-based polymers are efficient and effective in cement slurry that work as multifunctional additive and improve API properties and cement durability. The cellulose-based polymers work as multifunctional additive that reduces the quantity of other additives in cement slurry and ultimately reduces the operational cost of cementing operation. The comparative analysis of this study opens the window for petroleum industry for proper selection of cellulose-based polymer in designing of cement slurry.


Energies ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4683
Author(s):  
Elayne A. Araújo ◽  
Thaine T. Caminha ◽  
Evanice M. Paiva ◽  
Raphael R. Silva ◽  
Júlio Cézar O. Freitas ◽  
...  

Oil well cleanup fluids (pre-flushes) are intermediate fluids pumped ahead of the cement slurry; they are able to clean the well walls by removing the filter cake formed by the drilling fluid, and leave the surface water-wet. This work’s main objective was to use biodegradable microemulsion systems as cleanup fluids in order to reduce the environmental impact. Three microemulsion systems were formulated, each composed of an oil phase, a surfactant and three different aqueous phases: glycerol, glycerol:water (mass ratio 1:1), and fresh water. The results show that all microemulsion systems were effective with 100% filter cake removal, with a removal time of less than 60 s. The wettability test and fluid compatibility analyses exhibited advantageous performances, without phase separation, variations in viscosity, gelation, or flocculation. The compressive strength and X-ray diffractometry (XRD) analysis showed the influence of the glycerol on the cement slurry properties, with the compressive strength resistance ranging from 8.0 to 10.7 MPa, and resulted in the formation of portlandite.


2021 ◽  
Author(s):  
Ayoub AZIZ ◽  
Abdellah BENZAOUAK ◽  
Abdelilah BELLIL ◽  
Thamer ALOMAYRI ◽  
Iz-Eddine EL AMRANI EL HASSANI ◽  
...  

Abstract The geopolymer preparation based on natural pozzolan is a promising route. Thus, improving the physicochemical properties of these geopolymers by adding other volcanic rocks merits investigation. The present work aims to study the effect of perlite addition, as an acidic volcanic rock, on the physico-chemical and microstructural properties of geopolymers based on pozzolan (basic volcanic rock). The perlite proportion varied between 0 and 50%. A mixture of sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) was used as an alkaline activator. The perlite effect on the physico-mechanical properties of the synthesized geopolymers was evaluated by the compressive strength (Rc), P-wave velocity (Vp), bulk density (D), and porosity (P). The microstructural aspects have been explored by X-ray Diffractometry (XRD), Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), and Energy-Dispersive X-ray spectroscopy (EDS). The results highlight the possibility of obtaining an eco-efficient geopolymer, with compressive strength of up to 50 MPa at 28 days by partially replacing the pozzolan by 40% of the perlite, due to the formation of more amorphous N-A-S-H type gel. However, the excessive content (over 40%) of perlite had a negative effect on the development of the compressive strength and microstructure of the pozzolan-based geopolymer, which was related to the formation of zeolitic phases in the geopolymer matrix. This study confirms the promise of using pozzolan-perlite-based geopolymers as sustainable building materials, which could significantly promote the development of geo-resources and environmental protection in the construction sector.


2014 ◽  
Vol 941-944 ◽  
pp. 1441-1444 ◽  
Author(s):  
Jing Fu Zhang ◽  
Kai Liu ◽  
Rui Xue Hou ◽  
Bo Wang ◽  
Jin Long Yang

The compressive strength of oil well cement would be damaged by high temperature in deep oil wells, which was caused by the obvious change of the components and microstructure of cement hydration products. The adaptability of common oil well cement for cementing under higher temperatures was confined by above reasons. Characteristics of development and change of compressive strength of Class G oil well cement were studied under different temperatures by using Static Gel Strength Analyzer and High Temperature-High Pressure curing chamber. The influence law of temperature and silica sands on compressive strength was analyzed. The results showed that the critical temperatures at which the compressive strength begun to decline were about 110°C and 150°C respectively; The compressive strength increased with curing time during the initial period and would reduced after it reached a certain value when temperature exceeded 110°C; For cement with silica sands, the compressive strength development trend was in the shape of two-stage form with increase of curing time within the range of 110~150°C, but for 160~200°C temperature range the development form was in the shape of single stage; The reasonable amounts of silica sands which would be added to cement slurry to enhance the compressive strength of hardening paste were determined to be 30%~40%.


2016 ◽  
Vol 841 ◽  
pp. 148-156 ◽  
Author(s):  
Alagu Karthik Valliappan ◽  
Raja Rajeswary Suppiah ◽  
Sonny Irawan ◽  
Ridho Bayuaji

For many years, Ordinary Portland Cement (OPC) is used in oil well cementing operation. But the OPC gets degraded in the acidic environment because of having poor mechanical characteristics. A new technology called geopolymeric cement system is developed from the secondary byproducts of the industry to replace the conventional cement slurry in oil well cementing operation. This study focus on the preparation of cement slurry with new formulation using fly ash and alkali binders at two sodium hydroxide treatment methods with various concentrations of NaOH solution and analyzing the prepared cement slurry for compressive strength, defiance to acid and fluid loss amount. Different cement slurry compositions made of 70:30 fly ash to alkaline activator ratios with 10, 12, 14 Molar NaOH solution with two sodium hydroxide treatment methods of direct addition and mixing after one day soaking of NaOH were prepared and cured for 24 hours at a temperature of 80°C and pressure 3000 psi. The obtained cement specimens were tested for compressive strength, resistance towards acid and density. Then based on the results, geopolymer can be considered as alternative for Class G cement in oil well cementing operation due to its high compressive strength and high acid resistance.


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