In non-stick heavy-bottom Dutch oven over medium heat, cook sausage until browned, about 5 minutes. Transfer sausage to paper towels. Add onion, celery, bell pepper and garlic to pot; cook until vegetables have softened, about 4 minutes. Stir in rice, salt, thyme and cayenne; cook and stir, about 1 minute. Stir in tomatoes with juice, clam juice, chicken broth and browned sausage; mix well. Bring to boil, reduce heat to low; cover and simmer 10 minutes. Scatter shrimp and scallops over rice; cover and cook until rice is fully tender and shrimp are opaque and cooked through, about 10 minutes more. When seafood is done, stir in parsley.