Tiro (Antimony-Sulphide) And Potash As Local Substitutes To Imported Barite And Lignosulphate In Drilling Mud Weighting Additives

Transcription

1 International Journal of Engineering & Technology IJET-IJENS Vol: 11 No: Tiro (Antimony-Sulhide) And Potash As Local Sustitutes To Imorted Barite And Lignosulhate In Drilling Mud Weighting Additives Adeayo, Thomas A. Imokhe, Omolegho Det. of Petroleum Engineering, Covenant University, Ota-Ogun, Nigeria Astract A variant of Antimony Sulhide, locally called Tiro (stinite), which has een used locally for centuries y Northern Nigerian women as a eauty roduct was emloyed as a drilling weighting material, due to its weight and aarent health safety, as a sustitute to exensive and imorted Barite. Potash, locally called Kaun, was also used, as a local sustitute to Lignosulhate, as a thinner in drilling. The imlication of using the Tiro and otash were comared with that of arite and Lignosulhate resectively in this research. Results otained show that less weight of Barite is needed for equivalent weight of Tiro as the weight increases and it was also oserved that effect of Barite on H is lower than that of corresonding Tiro. Unfortunately, it was oserved that the effect of Barite on viscosity as weight of Barite in the increases has a dangerous effect on the viscosity of the. In the case of Tiro, viscosity of was maintained until a 5% weight of Tiro in. Viscosity is the measure of the aility of the to susend drill cuttings and clean the well for faster drilling. Maintaining viscosity of drilling is of aramount imortance and for a that is emloyed for drilling dangerous zone, Tiro may e a etter alternative to arite if the safety of the well is of high consideration due to Tiro's lower negative effect on viscosity than arite. For the thinners, it was oserved that oth Lignosulhate and Potash have same reducing influence on weight of u to 1.58% weight comonent of the thinners in the mixture after which the otash caused a drastic reduction in density with increasing weight ercentage of the additive. The two thinners had reducing effect on the H of u to 0.67% weight of additive after which the H of remains constant no matter the increase in ercentage thinner additive weight. While otash caused a decrease of 8.7% in H value, Lignosulhate caused an equivalent 1.6% reduction in H value. This reduction in H y weighting materials is significant ecause it makes the to ecome more acidic and H of a drilling actually affects the erformance of the. Usually H is desirale etween 8.0 and 9.0 for otimum hydration [7]. This gives Potash more relevance than Lignosulhate. Also when there is need to raidly reduce the density due to the ossiility of lost circulation as a result of over-weight, esecially when anormal low ressure zone is encountered during drilling, otash will e a more effective thinner as it caused raid reduction in density. From the oservations and measurements carried out during this research, some model equations were roosed. Keywords-Tiro, Antimony sulhide, Potash, Lignosulhate, drilling, weighting additives and thinners. I. INTRODUCTION Stroud [1] suggested that driller should consider weight more imortantly than the consistency in use at that time. This he stated is due to the hazard of gas-cutting of thick. He also stated that success or failure in drilling a well in the Monroe (La.) gas field deended uon the control of the gas ressure y heavy. Based on various laoratory tests using cement, galena and iron oxide (hematite, Fe O 3 ) as materials for increasing the density of it was discovered that. Iron oxide could e used to raise density to 16 I/gal without an excessive increase in consistency of the thereafter it was used successfully in several fields. In the fall of 19, igment-grade Missouri arite was used as a weighting material to make a heavy. Wayne [] introduced the first thinning agent and it was a mixture of chestnut ark extract and sodium aluminates called Stailite. It was discovered that it was ale to thinned without decreasing the density and also caused a released of entraed gas, therey allowing further increase in weight for higher ressure control. The comosition of the Stailite was later altered to include molecularly dehydrated hoshates as a comonent. Okumo [3] carried out research on the effect of temerature and otash on drilling. They emloyed the rincile and method of factorial design to develo a model. They used the model for rediction of drilling fluid viscosity at varying temeratures. Cassava starch and otassium caronate were used as local additives in the drilling fluid. 3 full factorial design exeriments with variales such as temerature, starch and otash were conducted and corresonding viscosities were otained. Irawan [4] use local additives such as corn cos and sugar cane wastes as viscosifier in drilling using Saraar-147, a synthetic-ased drilling formulation. It was discovered during this study that the lastic viscosity and yield oint of the is directly roortional to the amount of the local additives added to the. Barite is used in aout 77% of rearation worldwide as a weighting agent for water-ased and oil-ased drilling fluids [5]. It is the most imortant weighting additive which

2 International Journal of Engineering & Technology IJET-IJENS Vol: 11 No: makes it very exensive. Hence, the need for a research on local and cheaer alternatives. Potash (Kaun) in Nigeria is edile and is defined as a rock salt and an ingredient "usually added to food esecially ulses during cooking for faster tenderisation and to increase the viscosity in Okro and Ewedu sauce. Also used for emulsifying oil and water in some traditional sou"[6] II. METHODOLOGY Simle water ased was reared using.5g of entonite to 350ml of water. Physical roerties of the were carried out to otain the average density, H, gel strength and viscosity at different seeds of viscometer. Varying weights of Tiro, Antimony sulhide, of 5g, 10g, 15g, 0g, 5g and 30g were added to fresh samles and the corresonding density, H and viscosity were measured using alance, H meter and viscometer resectively. Barite was used instead of Tiro as weighting additive and the same tye of measurements were made also. Results otained for the Tiro and that of arite were comared and lotted in Fig Various granulated weights of.5g, 5g, 7.5g and 10g of otash, as local thinners, were added to fresh samles of and corresonding roerties of the were measured as in the case of weighting material. Various weights of.5g, 5g, 7.5g and 10g of lignosulhate, as thinners, were added to fresh samles of and corresonding roerties were measured just like that of otash. Measured results were comared for the otash and the lignosuhate and lotted in Fig.4-6. III. RESULTS The keasure roerties of the as weight of additives are added are resented in Tale 1-6 elow and the data is lotted in Fig.1-6. Tale 1 gives the effect of increasing weight of Tiro and Barite on the density of the drilling while Tale gives the measured effect when the thinners, Potash and Lignosulhate, were used. Tales 3-6 gives the effect of increasing weight of the additives, weighting and thinners, on the viscosity of the drilling using Vann Viscometer. Tale 1: OF ADDITIV E (g) Effect Of Weighting Additives On Mud Density And H TIRO BARITE Tale : Mud Density and H Variation With Weight of Thinner Additives OF ADDITIVE (g) OF LIGNOSULATE POTASH Tale 3: Viscosity And Gel Strength Reading For Tiro Additive GEL ST (10SEC) GEL ST (10 MIN) YEILD POINT

3 Tale 4: Viscosity And Gel Strength Reading For Barite Additive International Journal of Engineering & Technology IJET-IJENS Vol: 11 No: OF GEL ST(10SEC) GEL ST(10 MIN) YEILD POINT Figure 1. Grah of Mud Weight At Various Weight of Additives Tale 5: Viscosity And Gel Strength Reading For Lignosulhate Additive OF GEL ST(10SEC) GEL ST(10 MIN) APP ERENT YEILD POINT Figure. Grah of H Variation With Weight of Additives Tale 6: Viscosity And Gel Strength Reading For Potash Additive OF GEL ST(10SEC) GEL ST(10 MIN) TIELD POINT Effect of weight of addtives on the weight is shown elow in Fig.1 and it was discovered that Barite gave etter weighting strenght than Tiro. Figure 3. Grah of Viscosity Variation With Weight of Additives

4 International Journal of Engineering & Technology IJET-IJENS Vol: 11 No: Figure 4. Grah of H Variation With Weight of Thinners Weight of Additives (g) Figure 5. Grah of Mud Weight Variation With Weights of Thinners Figure 6. Grah of Viscosity Variation With Weight of Thinners. IV. CONCLUSION Effect of added weight of additive on the average H of the is shown in Fig. aove for weighting additives and Fig.4 for thinners. The desirale H of the is etween 5.0 and 8.0 in order not to have adverse effect on elastomers as stated y R & M Energy [8]. The Fig. shows that the Tiro caused a more raid reduction in the highly asic than arite and ring the H near the desired value. There is tremendous increase in staility of entonite clay in when the H is increased from the normal range of to range 10.5 to 11.5 [9] which tends to favour Barite over Tiro. Many users of H as measurement of corrosion fatique of drill ies and casing considered that a H of less than 9.5 will shorten the corrosion fatique of drill stem [10] and this tends to favour Tiro over Barite. Various equations that relate the weight of additives to that of the measured roerties, using the trends of the various measured data, were otained in the course of this research and are stated elow as roosed model equations relating the density to that of weight of additives and also H to the weight of additives. The roosed equations are as follows: i. DENSITY 0.006m 0.01m tiro m 0.00m L m m m L m m Equations 1 to 4 relates the mass of weighting additive to the density where: m = weight of arite added to the m tiro = weight of tiro added to the m = weight of otash added to the m L = weight of lignosulhate added to the ρ = density of. ii H EQUATIONS. H m 0.079m H 0.003mtiro mtiro Where H is the measure H of the. For the thinners, otash and lignosulhate, the H values of the remains constant after the first reduction due to addition of the thinner (Fig. 5). This imlies that the two thinners have no effect on the H values when the amount in is increased and hence can e used without having any adverse effect on the equiment. The conclusion from this research is that Barite gave etter erformance on weight increase and H maintenance than the corresonding weight of Tiro though the difference on the effect of the weight is not much ut the effect on H must e considered. Unfortunately, the arite gave unreliale influence on the viscosity of the while tiro gave etter erformance on density. Tiro is therefore recommended as the referred weighting material ut its use should e comined with the addition of another additive that will maintain the H of the. Moreover, oth otash and lignosulhate roved to e very close sustitute esecially at low ercentage reduction in

5 International Journal of Engineering & Technology IJET-IJENS Vol: 11 No: weight. Potash gave a etter result in H maintenance than the lignosulhate and so is more reliale as a thinner. Further work is recommended on the study of effect of high temerature and ressure on these materials to find out if the same oserved effects will still e otainale inside the well during drilling urose. REFERENCES [1] Stroud, B. K., Alication of Mud-Laden Fluid, Oil Weekly June 5,195,.9-30 [] Wayne, T. B., Treatment of Drilling Fluids, U.S. Patent No.,94,877 (Set.1, 194). [3] Okumo, I. and Isehunwa, O.S, (007): Effect of Temerature and Potash on the viscosity of Simle Drilling Fluids Treated With Cassava Starch. SPE aer ( [4] Sonny Irawan, Ahmad Zakuan Ahmad Azmi and Mohd. Saaid, Corn Cos and Sugar Cane Waste as a Viscosivier in Drilling Fluid, Pertanika J. Sci. & Technol. 17 (1): (009) [5] en.wikiedia.org/wiki/barite [6] Nigerian Recies htt:// [7] Mixing and Using Drilling Mud, htt/ [8] R & M Energy System, Technical Bulletin T0103, Drilling Mud H and Effect on Elastomers,Rev.1, Noveer 19, [9] Amrose, H. A. and A. G. Loomis, Chemical Treatment of Rotary Drilling Fluids - Stailization of Weighted Disersions: Effect of H Value, Ind. Eng. Chem., 1933, 5 (9), [10] Azar, Jamal J., and Lummus, James L, The Effect of Drill Fluid H on Drill Pie Corrosion Fatigue Performance, Fall Meeting of the Society of Petroleum Engineers of AIME, 8 Setemer-1 Octoer 1975, Dallas, Texas AUTHORS PROFILE Adeayo, Thomas Ayotunde is a Lecturer at Covenant University, Ota, Ogun State, Nigeria. Imokhe Omolegho is a recent graduate of Petroleum Engineering Deartment of Covenant University, Ota-Ogun, Nigeria.