Possibly. A grinding station usually produces much heavier particulate matter than a welding station. This means a dust collector must maintain a higher air velocity to address dust from a grinding station. Heavier particulates need faster airflow so that they won’t drop out of the air stream. An air quality engineer would be able to study the dusts involved (and their volume) and advise on what is possible.
Another variable to consider is how many ports your dust collector is currently designed for. Most likely, the existing ductwork and filtration system have been sized for the existing welding needs. Adding a new port would cut airflow through all of the existing ports, affecting capture rates throughout the system. Again, an engineer would be able to consult on this issue.
Types of dust are another factor with this question. For example, you cannot mix aluminum grinding dust with ferrous metals, or a fire/explosion will result.