ANNEX III HIGH PRESSURE HYDROLYSIS BIOGAS PROCESS

1. High pressure hydrolysis biogas process means treatment of animal by-products under the following conditions:

(a)

The animal by-products are first processed using processing method 1 in a processing plant approved in accordance with Regulation (EC) No 1774/2002;

(b)

Following the above process, the defatted materials are treated at a temperature of at least 220 °C for at least 20 minutes at a pressure (absolute) of at least 25 bar, heated in a two-step procedure, first by direct steam injection, secondly indirect in a coaxial heat exchanger;

(c)

The process is carried out in a batch or continuous system and the material is constantly mixed;

(d)

The animal by-products are treated in such a manner that the time-temperature-pressure requirements are achieved at the same time; and

(e)

The resulting material is then mixed with water and anaerobically fermented (biogas transformation) in a biogas reactor.

2. In case of treatment of Category 1 animal by-products:

(a)

The entire process takes place on the same site and in a closed system;

(b)

The biogas produced during the process is combusted rapidly in the same plant at a minimum of 900 °C followed by rapid chilling (‘quenching’), and an appropriate gas clean-up system is in place to exclude contamination with protein residues of the biogas or the gases derived from its burning.

3. The process is designed to process material coming out of a conventional rendering plant using processing method 1. This material is treated in accordance with point (1) (b), subsequently mixed with water and submitted to biogas fermentation.