Coffee: Ground coffee has a nice, crisp natural aroma. Just put about a cup of ground coffee in a flat, uncovered container. Place the container inside the confined space for several days. If the bad smell is extremely horrible, put more ground coffee. The area will smell of fresh coffee for many days.
Charcoal: Charcoal is on the top of the list of smell deodorizers as it is one of the best absorbent agents that can soak up the bad odor. Charcoal is also widely used as water filters and in most odor-removing commercial products. You can put a medium-sized chunk of charcoal inside your smelly patio for instance, and leave it there for a couple of days. You will notice that it can effectively remove the trash can smell.