That is: are there Korean words in which Hanja is used just to represent sounds regardless of the meaning of the characters employed?
Shortest answer will be 'yes, it has'.
According to Korean Wikipedia(https://ko.wikipedia.org/wiki/%EC%B7%A8%EC%9D%8C) it is called '취음(chui-um)' or '군두목(goondumock)'. One of the most well-known examples is how we call USA: 미국(美國), meaning 'beautiful country' but that is totally not intended. When Chinese people heard 'America' a few centuries ago, they thought it sounded like 亞美利加(Yàměilìjiā) and that spread to nearby country: the reason why now we call America as 미국.
We also made some chinese characters in order to symbolize some pronunciations: 乭(sounds like 'dole') is one of the examples.