It is said this circuit to regulate current through the load. This opamp is connected in openloop config and confusing me.

How does it work?

 

Why do you say that it is open loop? It is clearly closed loop control.

Note that the voltage on the + pin of U1 is acting as a reference voltage. An increase in the opamp output will drive the transistor base and cause the emitter current to increase. This increase will cause the voltage on the - pin of U1 to increase. If the voltage on the - pin exceeds that of the + pin, then the output of the opamp will be driven down. This lowers the transistor current and lowers the - pin voltage. This is negative feedback. Assuming that the feedback is stable, then the current in the collector and emitter legs of the transistor will be precisely controlled because the + and - pins of the opamp will have nearly equal voltage.

 

I thought it was an openloop because there was no feedback(no direct feedback from the output to the -pin).

Thank you for ur explanation