A sump normally pumps clear water as opposed to a sewerage ejector which pumps effluent.
Where these pumps discharge to is dependent on local codes and availability of either a storm or soil or waste pipe.
If your talking ground water or air conditioning condensate then a sump pump is ideal for these types of conditions If the impeller can take the pH of the water being pumped but thats another subject..
Most sump pumps do NOT require any type of venting as they are installled in open pits. I hope this helps.
To add to the prior message, a sump pump is there to protect your basement’s foundation from cracking due to water pressure under the floor. A good article on sump pumps can be found at http://www.zoeller.com under the Tech Topics Button. Look for an article titled “The Sump Pump: A Home’s Hidden Alley”.