Blockchain technology can be used wherever large databases need to be stored in open access mode while maintaining a high degree of security. In the Internet system, this opens up unlimited possibilities, since it allows you to cover certain types of activities at once across the globe.
Yes, that's the beauty of this technology because it lets you have limitless possibilities because it can have a wider scope in a trustless system. Unlike in the technology that we have nowadays that is mostly centralized wherein there is a limit as to who can access it and then those who handle the system can freely do to whatever information is there in the system since they are the authority while in blockchain technology, it needs a permit to more than half of all the people who has access to it which makes it next to impossible of being hacked.
As for the usage of blockchain technology without cryptocurrency, yes it is possible because it can exist without the other while cryptocurrency cannot exist without blockchain technology.