Macerator pumps are handy for RVers who like to dry camp or http://www.examiner.com/article/what-is-rv-boondocking. This garbage disposal for sewage lets you pump sewage uphill in camp sites where the sewer fitting is, bizarrely, uphill. This device extends the possibilities of RV camping and allows you to take advantage of spaces you might otherwise avoid.
The macerator pump connects to the RV's sewer connection with a standard bayonet connection. A cylinder that contains the electrical pump and macerating blades extends outwards from this connection. The blades look like a small propeller; the name comes from the word "to chew." A 12-volt motor powers the whole device; your macerator comes with an electrical connection that you wire into your power source--usually a 12-volt system.
On macerator's body are two screw-in hose connections. For both, use a hose that is solely for sewage. Try using a red hose for the outgoing hose (danger!) and a gray one for incoming flush water. Fit the incoming hose with a back-flow valve to prevent contamination of your fresh water.
You control the pump with a simple on-off switch that you can run through a window or other opening. When you need to run the macerator pump, close the gray valve on your sewer connection, open the black valve, then press the button to start grinding. The tone of the pump will change once most of the material is emptied out. Pour a bucket of water into the toilet or flush a couple of times, then switch off, close the black valve, and open the gray valve.
Finally, run the pump briefly to flush it (using that gray hose we mentioned earlier). Make sure to not let the macerator run dry as it will run dry. You can pick up this device in camping stores.