Scaling in arduous conditions; surface deposition mechanisms and kinetics
Lead Research Organisation:
University of Leeds
Department Name: Mechanical Engineering
Abstract
Mineral scale formation or mineral fouling is the deposition of unwanted materials on solid surfaces to the detriment of their function. It is one of the most significant threats to equipment integrity and production in various domestic and industrial processes. This includes oil and gas production, chemical and petrochemical plants, water treatment, heat exchangers, and heat transfer appliances.
In the oil and gas industry, fouling results in flow assurance problems, significant loss in production, safety risks and associated operational costs. Calcium carbonate (CaCO3) 'scale' is one of the most common mineral minerals found in the oil and gas industry. The main factors causing CaCO3 deposition are pressure and temperature changes as well as the mixing of incompatible waters.
Accurate prediction of CaCO3 surface deposition requires both thermodynamics models to indicate the tendency for scale formation in the bulk solution and kinetic models to predict the rate of scale accumulation. Understanding the precipitation and deposition of scale requires a suitable methodology for developing an accurate deposition kinetic model that would significantly improve the accuracy of predicting surface scale formation.
This research focuses on understanding the mechanisms of bulk precipitation and surface deposition at low saturation ratios (1 to 20) and mid-range temperatures (25-95oC) when considering oil and gas production. This project will utilise a novel in-situ visualization flow set-up to follow the scale build up on surfaces to evaluate nucleation and growth mechanisms and their effects on the overall kinetics, with the focus on developing new methodologies for evaluating mineral scaling and determining precipitation kinetics accurately at low saturation ratios in oil and gas systems.
In the oil and gas industry, fouling results in flow assurance problems, significant loss in production, safety risks and associated operational costs. Calcium carbonate (CaCO3) 'scale' is one of the most common mineral minerals found in the oil and gas industry. The main factors causing CaCO3 deposition are pressure and temperature changes as well as the mixing of incompatible waters.
Accurate prediction of CaCO3 surface deposition requires both thermodynamics models to indicate the tendency for scale formation in the bulk solution and kinetic models to predict the rate of scale accumulation. Understanding the precipitation and deposition of scale requires a suitable methodology for developing an accurate deposition kinetic model that would significantly improve the accuracy of predicting surface scale formation.
This research focuses on understanding the mechanisms of bulk precipitation and surface deposition at low saturation ratios (1 to 20) and mid-range temperatures (25-95oC) when considering oil and gas production. This project will utilise a novel in-situ visualization flow set-up to follow the scale build up on surfaces to evaluate nucleation and growth mechanisms and their effects on the overall kinetics, with the focus on developing new methodologies for evaluating mineral scaling and determining precipitation kinetics accurately at low saturation ratios in oil and gas systems.
