A control system and a method for controlling the exhaust gas flow in an exhaust line of a combustion engine

A vehicle comprising a control system for controlling exhaust flow in an exhaust line of a combustion engine, wherein the exhaust line comprises at least one exhaust treatment component and an evaporator of a waste heat recovery system, and wherein the control system comprises:

• a valve arrangement in the exhaust line;
• a temperature sensor configured to sense a temperature related to a temperature of the exhaust treatment component;
• and
• a control unit configured to position the valve arrangement in a first position, when the exhaust treatment component has a lower temperature than a specific temperature of exhaust gases that are directed to flow through the exhaust treatment component before being directed to flow through the evaporator, and to position the valve arrangement in a second position, when the exhaust treatment component has a higher temperature than a specific temperature of the exhaust gases that are directed to flow through the evaporator before being directed to flow through the exhaust treatment component,
• wherein the valve arrangement comprises a valve member or a valve part configured to change flow direction of a working medium in the evaporator, such that the working medium and the exhaust gases always flow in opposite directions through the evaporator.

A method for controlling the exhaust flow in an exhaust line of a combustion engine in a vehicle, wherein the exhaust line comprises at least one exhaust treatment component and an evaporator of a waste heat recovery, a valve arrangement, wherein said method comprises:

• directing exhaust gases in the exhaust line to flow through the exhaust treatment component before being directed to flow through the evaporator, when the exhaust treatment component has a lower temperature than a specific temperature;
• directing the exhaust gases to flow through the evaporator before being directed to flow through the exhaust treatment component, when the exhaust treatment component has a higher temperature than said specific temperature;
• and
• changing flow direction of a the working medium in the evaporator, such that the working medium and the exhaust gases always flow in opposite directions through the evaporator.