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The main goal of this study is to extend shelf life of oil and gas pipelines and storage facilities made essentially of mild steel from effects of acid corrosion during industrial operation such as acid pickle, cleaning and descaling using cost-effective approach. To accomplish this, mild steel was immersed in 1 M HCl solution in absence as well as presence of sodium carboxymethyl cellulose (SCMC) solely and in mixture with potassium iodide (KI) and polyethylene glycol (PEG) respectively to ascertain inhibitive capability of the compounds using weight loss measurements at 30‒60 ˚C for 24‒120 hr immersion and potentiodynamic polarization technique at 30 ˚C. Inhibitory performance of SCMC was good (64.12 %) at 500 mg/L which was made better by increasing concentration to 2000 mg/L (80.86 %) and much better on mixing SCMC with KI and PEG to yield 90.91 and 94.02 % respectively at 30 ˚C for 24 hr immersion. However, extending immersion time and temperature unfavourably affected inhibition efficiency of the compounds. Corrosion inhibition of the compounds was afforded by physical adsorption of the compounds on the mild steel surface according to thermodynamic considerations. Adsorption followed Langmuir isotherm model. The compounds were found to behave as mixed type inhibitors by curbing both anodic and cathodic reactions on the mild steel surface in 1 M HCl solution by potentiodynamic polarization study.