Method for Draining Thermal Oil in a Thermosolar Plant, and Corresponding Auxiliary Installation for Carrying Out Said Method

An auxiliary installation for draining thermal oil at a thermal solar plant, which includes main conduits and loops, each of the loops being isolated from said main conduits by first valves and with each loop corresponding to a set of solar collectors arranged in series, and further including second valves at ends of the loops for external connection, the auxiliary installation comprising the following elements:

• an oil tank;
• a pumping system;
• a depression/suction system;
• first conduits for communication with the second valves;
• a second conduit for communication between the oil tank and the pumping system;
• third conduits from the oil tank and pumping system for communication with the second valves;
• and
• a set of opening/closing flow valves between the oil tank, the pumping system;
• the depression/suction system and the first through third conduits;
• the third conduits for communication with the second valves including two corresponding pairs of hoses, one of the hoses in each pair connected to the other to form first and second closed loop branch circuits, each of these branch circuits having a connection at a free end thereof with a corresponding said second valve of the loop of the thermal solar plant, and without said branch circuits having any valves at their free ends.

A method for draining thermal oil at a thermal solar plant which comprises the following steps:

• connecting an end of branch circuits formed of two pairs of hoses at valves of a loop of the thermal solar plant;
• filling each of first and second branch circuits with oil from an oil tank by pumping the oil with a pumping system;
• opening the valves for connecting the loop of the thermal solar plant;
• scavenging oil in the loop through one of conduits of each of the branch circuits, with this oil circulating through a cooling system, and this scavenging step being performed by driving cold oil by the pumping system;
• providing suction by a depression/suction system of the oil from the branch circuits and taking this oil to the oil tank;
• and
• closing the valves.