Refiner and glass melting plant

A glass melting plant comprising:

• a melt crucible and
• a refiner comprising:
• a tank configured to accommodate the glass melt, the tank having a front end and an outlet at a rear end, with a direction of transport of the glass melt flowing through the tank extending from the front end to the rear end,
• the tank having a floor, two side walls extending substantially parallel to the direction of transport, and a superstructure situated above the side walls and upwardly terminating the tank,
• a barrier, in the form of a raised part of the floor, situated on the floor of the tank and running essentially in the direction of transport, the barrier forming with the side walls, at least in a front region in the direction of transport, at each lateral side of the barrier, a channel-shaped constriction of the tank, a width of each constriction transverse to the direction of transport being at most 0.45 times the width of the tank,
• at least one first fossil fuel heating device situated in at least one of the superstructure or the side wall, the first heating device configured to heat the glass melt from above, and
• at least one second electrical heating device situated in at least one of each side wall or in the floor of the tank in the region of each constriction, the second heating device extending into the glass melt and being configured to heat the glass melt.
• wherein raw materials are supplied to the melt crucible by a supply device and melted there, an outlet of the melt crucible situated opposite the supply device being connected to an inlet of the refiner situated in the superstructure at the front end of the refiner.