Water Softener / RO Drainage Options

Howdy folks! So, about a month ago, we had a Kinetico Twin-tank water softener installed, as well as a K5 RO system. We're happy with the results so far... But, there's at least one regeneration a day, and the RO system yields a pretty consistent amount of waste water. Right now, all of this waste water goes into my sump, and I've got an electric sump pump which handles it. However, the sump does need to drain probably 4 times during a regeneration cycle, and then intermittently with the RO drain. I don't really like that it has to drain so much, and have been looking at battery backups for my sump. For a good system (Basement Watchdog Special +) with the battery and all that, I estimate around $500 to get that done, and a lot of effort, and a lot of parts in a relatively small sump. My question is, does anyone here have experience with draining softener/RO hoses right to the septic waste line (not sewer, septic)? It would be easy to access, and if I get hooked up with the air-gap and check valves, I feel like it would be a great solution for hopefully less than the $500 I'd spend on the backup sump pump. Thoughts?