Systems and techniques for heating polymer reactor flashlines

A polymerization system comprising:

• a polyolefin reactor having a reactor outlet;
• and
• a polyolefin reactor flashline heater system comprising:
• an enclosure defining a polyolefin reactor product inlet coupled to the reactor outlet and a heated product outlet;
• a plurality of heating sections contained in the enclosure and fluidically coupled in series between the polyolefin reactor product inlet and the heated product outlet, each heating section comprising one or more pipe sections formed of an electrically conducting material;
• a plurality of transformers, each transformer electrically coupled to a respective heating section and configured to heat the respective heating section by impedance heating;
• and
• a controller configured to independently adjust a heat input to each of the plurality of heating sections based on operating conditions.

A method of vaporizing hydrocarbons in a polyolefin product stream, the method comprising:

• continuously flowing the polyolefin product stream from a reactor outlet of a polyolefin reactor through a polyolefin reactor flashline heater system comprising a plurality of heating sections, each heating section comprising one or more pipe sections formed of an electrically conducting material;
• applying, by respective transformers, electrical power to respective heating sections to generate impedance heating of the polyolefin product stream to a predetermined temperature sufficiently high to vaporize at least a portion of the hydrocarbons in the polyolefin product stream;
• and
• adjusting, by a controller, a heat input to one or more of the heating sections based on operating conditions.