Nanopaint application for flow assurance with electromagnetic pig

Wax, hydrates, and asphaltenes precipitate in subsea pipelines and restrict the transport of hydrocarbons. Traditional wax prevention and dewaxing methods include thermal, chemical, and mechanical approaches. This paper investigates a new electromagnetic pigging method combined with a ferromagnetic nanopaint for potentially high heating efficiency and low maintenance cost. The electromagnetic pig could be inserted into the pipeline to generate induction heating; a nanopaint coating on the inner wall of the pipeline enhances the heating effect. To evaluate the effectiveness of the proposed system, we calculate the maximum pig speed, which is the fastest a pig can move through the pipeline and effectively dislodge wax deposits by heating. Systems with a higher maximum pig speed can dewax a pipeline in a shorter time. Numerical models are used to analyze the heating performance for different system configurations. Simulation results show that the proposed pigging tool can effectively heat and melt the deposited wax. The maximum pig speed is a function of the pig induction coil length and radius. The hydraulic shape of the pig does not impact the heating effectiveness.