Fill a large pot with water and place over medium high heat.
Once the water comes to a boil, add a small handful of salt and add the orzo. Boil orzo until al dente, stirring occasionally.
Drain orzo and transfer to a mixing bowl. Set aside.
Place a large skillet over medium-high heat and add 1 tablespoon of butter. Once butter has melted add shallot and garlic and sauté for 1 to 2 minutes.
Add the capers and continue to sauté for an additional 1 to 2 minutes.
Remove the mixture from the heat and pour over the orzo. Add ½ lemon zest and juice, toss together and season with salt and pepper. Set aside.
Return skillet over medium heat and add remaining butter. Allow butter to melt and barely brown, but not burn.
Pat scallops dry and generously season with salt and pepper.
Raise the stove heat to medium-high and sear the scallops on each side for 2 to 3 minutes. Remove from heat.
To assemble: Add grapefruit segments to the orzo mixture and toss together. Pour orzo mixture onto a platter and top with scallops. Spoon some of the brown butter over the scallops and finish with remaining lemon zest. Serve.