A method for treating solid organic materials includes providing phagotrophic algae, providing solid organic material, combining the algae and the solid organic material, allowing the algae to grow by engulfing or uptaking the solid organic material, forming an algal product, and collecting the algal product. The method can also include a pretreatment step. The solid organic material can be waste activated sludge. A system for treating and disposing solid organic material is also provided.
