Global Journal of Researches in Engineering, G: Industrial Engineering, Volume 23 Issue 2

Table 4 shows the p-values that determine whether the effects are significant or insignificant. Table 4: Estimated Regression Coefficient for CPR (mm/year) 21 130 580 150,000 5.65 4.5270 4.5465 22 100 360 240,000 5.51 5.1253 5.1061 23 115 470 195,000 5.58 5.1139 5.1161 24 130 470 195,000 5.58 5.5782 5.5235 25 130 580 240,000 5.65 5.9883 5.9808 26 115 470 150,000 5.58 4.4618 4.4590 27 115 470 195,000 5.58 5.1139 5.1161 28 130 360 240,000 5.51 6.2590 6.2809 29 130 580 240,000 5.51 6.2377 6.2294 30 115 470 195,000 5.58 5.1139 5.1161 31 115 470 195,000 5.65 5.0077 5.0085 Term Effect Coef SE Coef p-Value Constant 5.11609 0.00721 0.000 Significant Temperature (ºF) 0.79277 0.39639 0.00573 0.000 Significant Pressure (psig) 0.04859 0.0243 0.00573 0.001 Significant Flow Rate (bbl/day) 1.19657 0.59829 0.00573 0.000 Significant pH -0.20439 -0.10219 0.00573 0.000 Significant Temperature (ºF)*Temperature (ºF) 0.022 0.011 0.0151 0.476 Insignificant Pressure (psig)*Pressure (psig) -0.1042 -0.0521 0.0151 0.003 Significant Flow Rate (bbl/day)*Flow Rate (bbl/day) -0.1176 -0.0588 0.0151 0.001 Significant pH*pH -0.0109 -0.0054 0.0151 0.724 Insignificant Temperature (ºF) *Pressure (psig) -0.13484 -0.06742 0.00608 0.000 Significant Temperature (ºF) *Flow Rate 0.25436 0.12718 0.00608 0.000 Significant Temperature (ºF) *pH 0.00721 0.00361 0.00608 0.561 Insignificant Pressure (psig)*Flow Rate (bbl/day) 0.0312 0.0156 0.00608 0.021 Significant Pressure (psig)*pH -0.00353 -0.00177 0.00608 0.775 Insignificant Flow Rate (bbl/day)*pH -0.04789 -0.02395 0.00608 0.001 Significant CPR = -32.7 - 0.0215 T + 0.00963 P + 0.000044 FR + 12.1 pH + 0.000049 T*T - 0.000004 P*P- 0.000000 FR*FR-1.11 pH*pH - 0.000041 T*P + 0.000000 T*FR + 0.00344 T*pH + 0.000000 P*FR - 0.000230 P*pH - 0.000008 FR*pH (1) where: CPR: Corrosion Penetration Rate (mm/year) T: Temperature (ºF) P: Pressure (psig) FR: Flow Rate (bbl/day) pH: - © 2023 Global Journals Global Journal of Researches in Engineering Volume XxXIII Issue II Version I 33 Year 2023 ( ) G Modeling and Optimization of Corrosion Penetration Rate in Crude Oil Pipeline using Response Surface Methodology based on Aspen HYSYS Simulation Software The equation from table of estimated regression coefficients for corrosion penetration rate (mm/year) of the first – second order is given as equation 1: