Mix quinoa, black beans, celery, onion, and preserved lemon together in a large bowl.
Mix olive oil, 2 tablespoons orange juice, zest, apple cider vinegar, agave, salt, pepper, and coriander together in a small bowl. Pour over quinoa mixture. Toss gently to coat.
Substitute chopped mandarin oranges for the preserved lemons if preferred.
Substitute honey for the agave if desired, but then the salad is no longer vegan.