The olive mill wastewater (OMWW), also called alpechin, margine and jamila, is a mixture of vegetation water directly extracted from olives and oil production water, coming from washing and processing. The OMWW is by both. Being biologically characterized by the presence of wide array of microorganisms, including bacteria, fungi and yeasts, the OMWW typically has acidic pH and contains large quantities of organic nitrogen, potassium and polyphenols.
It is possible to reuse the OMWW for different purposes, like irrigation, compost, etc., only after suitable treatments to reduce salinity, organic content and acidity.

The pomaces, also called olive cake, husks and crude olive, are by-products composed by skins, pits, pulp and a variable percentage of wastewater, depending from the type of extraction (2-3 phases).  The pomaces typically have acidic pH and contain high concentrations of polyphenols and organic fatty matter. If properly treated, the pomaces become suitable for the production of amenders, compost and fuel.

Type of residue resulting from two-phase extraction mostly applied in Spain. Alperujo is composed by both OMWW and solid waste.

Residual paste, which is produced if the whole olive stones are removed from the paste prior to processing. This residual paste has very high water content and is difficult to store.

Due to high energy/power, the less expensive raw olive stones are commonly used instead of pellets for the production of fuel.

Branches, leaves and woods from the olive orchard are the only by-products which could be easily reclaimed as biomass.