Preheat oven to 350°F.
Cook broccoli according to package directions and drain any excess liquid thoroughly.
Melt butter in a large skillet and sauté celery and onion until tender.
Soften Cheese Whiz according to package directions.
In a large mixing bowl, combine rice, salt, milk, and cream of chicken soup.
Add the softened Cheese Whiz and sautéed vegetables to the rice mixture.
Fold in the cooked broccoli until evenly distributed.
Transfer mixture to a large greased casserole dish.
Bake uncovered for 1 hour at 350°F until bubbly and lightly golden on top.