Here are the docs for connection to SQLAlchemy with SQLite.
As you guessed, you are in fact creating a SQLite database in memory when you use sqlite://
as your connection string. If you were to use sqlite:///{}/arkaios.db'.format(PWD)
you would create a new database in your current directory. If this is what you intend to do so that you can access that database from other applications then you should import your connections string from your configuration file and use that instead of sqlite://
.