The composition of food scraps depend largely on the household's eating habits, so the answer may vary from household to household. Furthermore, the treatment of refuse and sewage differs from location to location.
One can only give some general guidelines, some of which will be within the domain of knowledge of the customer service departments of sewer and refuse organizations in your community. Other concepts may require inquiring in the environmental departments of your state or perhaps university researchers.
I'll assume you are interested in sustainable living in the wider sense and hope I am correct in that assumption.
Sustainability of a human circulatory system with regard to some fatty acids has one thing in common with the sustainability of a sewage system. Anything that enters in particulate or liquid form and, over time, forms attachments to the inner walls of the conduit will ultimately increase flow resistance until a complete blockage forms.
In the first case, flow resistance generally leads to high blood pressure and possible clot formation with the associated complications. Such a situation may lead to valve wear or heart fatigue, both of which can further lead to lethal malfunction.
In the second case, flow resistance eventually leads to sewage backup and expensive blockage removal procedures.
Whether in sewage or refuse, most fatty acids are biodegradable, meaning they are decomposed by microorganisms, mostly bacteria. What impact that has on buried refuse, exposed refuse, sewage in pipes, or sewage treatment will vary by climate and other factors.
One clear conclusion that a sustainability minded person can draw is basic and invariant by region or municipality: If you shop and cook in such a way that a drop of soap brings your cookware and dishes to squeaky clean (a simple test for fatty acids that cling to and lubricate smooth surfaces) two benefits are likely to co-occur.
- Your family will have lower risk of several chronic diseases.
- Your own home's plumbing and your municipality's sewer system will have fewer risks of malfunction too.