Global Water & Energy - RAPTOR® Unleashing the Power of Organic Waste
The RAPTOR process or Rapid Transformation of Organic Residues is a powerful process that converts energy crops and agricultural residues (called “substrate”) into valuable electricity and heat (or steam) by means of an enzymatically enhanced two stage biological fermentation process. The RAPTOR process starts from the collection of the crops or agricultural residues and ends with the production of biogas and green electricity or steam.
The crop or any agricultural waste, dry or wet, is conveyed into the supply hopper equipped with a cogged screw feeder.
A special shredder is installed between the feed pump and the hydrolysis reactor in order to reduce the particle size.
The slurry is subjected to a tailor made enzymatic treatment under pH and temperature controlled optimal conditions, depending on the type of substrate going to the process and the type of enzymes needed. The substrate typically contains a lot of cellulosic material which is partly converted into glucose through cellodextrin and cellobiose in the enzymatic hydrolysis step. Other carbohydrate like substrates, like starch, are also converted into smaller molecules, like glucose.
The thermophilic acidification reactor (TAR) is operated under anaerobic thermophilic conditions. Special seed material is supplied by GWE. The residual cellulose is converted into acetate, ethanol, lactate, hydrogen and carbon dioxide which are all excellent substrates for the next methanogenic step. All complex carbohydrates are fermented to a range of “volatile fatty acids”.
The outlet of the acidogenic stage is a concentrated wastewater that contains dissolved and undissolved organic matter. Excessive solids can be removed as needed. This preconditioned substrate is treated in an ANUBIX-C reactor. This high rate reactor is particularly suited for highly concentrated wastewaters.
The effluent of the methanogenic reactor, rich in minerals and some recalcitrant organic matter, is either used as fertilizer/irrigation water for the crops or further treated in a conventional anaerobic/aerobic or aerobic waste-water treatment plant.