Process for recovering feed-grade protein from animal manure

A process for recovering protein as an animal feed from animal manure of cattle, swine, and fowl which comprises the steps of:

• collecting the animal manure and forming an aqueous manure slurry containing from about 25 wt % to about 50 wt % water;
• holding the aqueous manure slurry in a tank for a period of from about 2.5 to about 4 days until free oxygen in the slurry is consumed by aerobic reaction;
• subjecting the aqueous manure slurry to anaerobic fermentation by mesophylic anaerobic bacteria at a temperature of from about 35° C. to about 65° C. for a period of from about 14 to about 30 days to allow anaerobic digestion to occur whereby a biogas methane and carbon dioxide is evolved and a feed compost slurry is produced;
• separating the feed compost slurry from the water until the water content of the feed compost slurry is from about 15 wt % to about 25 wt %;
• exposing the feed compost slurry to radio waves having a frequency of from about 915 MHz to about 2,450 MHz for a period of time sufficient to kill all pathogens in the compost slurry and to form a sterilized feed compost safe for consumption by animals as a source of protein;
• drying the sterilized feed compost at a temperature of from about 100° C. to about 190° C. until a water content of up to about 12 wt % is produced as a raw feed compost;
• and
• screening the rawfeed compost to separate the feed compost by size.

A process for recovering protein from animal manure for use as a sterilized animal feed which comprises the steps of:

• collecting the animal manure and forming an aqueous manure slurry therefrom;
• subjecting the manure slurry to anaerobic fermentation as an aqueous slurry at a temperature of from about 35° C. to about 65° C. for a sufficient length of time to cause a biogas to be produced from the slurry to yield a biogas stream and a feed compost slurry;
• sterilizing the feed compost slurry by exposing it to radio waves of sufficient intensity and for sufficient time to kill 100% of the pathogens in the compost and render a feed compost safe for consumption by animals as a source of protein;
• drying the sterilized feed compost;
• and
• recovering the sterilized animal feed compost for use in a feed product.

A process for recovering protein as an animal feed from animal manure of cattle, swine, and fowl which comprises the steps of:

• collecting the animal manure and forming an aqueous manure slurry containing from about 25 wt % to about 50 wt % water;
• holding the aqueous manure slurry in a tank for a period of from about 2.5 to about 4 days until free oxygen in the slurry is consumed by aerobic reaction;
• anaerobically fermenting the aqueous manure slurry in a digester using mesophylic anaerobic bacteria at a temperature of from about 35° C. to about 65° C. for a period of from about 14 to about 30 days to allow anaerobic digestion to occur whereby a biogas methane and carbon dioxide is evolved and a feed compost slurry is produced;
• separating the feed compost slurry from the water until the water content of the feed compost slurry is from about 15 wt % to about 25 wt %;
• exposing the feed compost slurry to radio waves having a frequency of from about 915 MHz to about 2,450 MHz for a period of time sufficient to kill all 100% of the pathogens in the compost slurry and to form a sterilized feed compost safe for consumption by animals as a source of protein;
• drying the sterilized feed compost at a temperature of from about 100° C. to about 190° C. until a water content of up to about 12 wt % is produced as a raw feed compost;
• and
• screening the raw feed compost to separate the feed compost by size.