I Cough Up A Scab Covered In Phlegm Almost Daily.

I cough up a scab covered in phlegm almost daily. Once hacked up it is done for the day. I can swallow it too but I find that gross! I don't have a cough or cold. This started about 5-7 years ago after my husband returned from deployment to Iraq. Not sure if pertinent. How do I stop the scabby mucus build up in my throat that occurres daily.