Fractionated stillage separation and feed products
This disclosure describes methods to separate solids from liquids in a production facility. A process separates components in the process stream by applying non-condensable media to create density differences and then using a mechanical device to separate the solids from the liquids based on the density difference. The process produces the liquids and solids, which may be further processed to create valuable animal feed products.
1. A method for separating components in a process stream, the method comprising:
receiving a process stream having a mixture of components of one or more liquids and one or more solids;
adding a non-condensable media to the mixture to change a density of each of the components, wherein the non-condensable media is selected from the group consisting of air, carbon dioxide, nitrogen, oxygen, and combinations thereof;
separating the one or more liquids and the one or more solids of the process stream using an apparatus selected from the following:
a sedicanter centrifuge, a decanter centrifuge, a disk stack centrifuge, and combinations thereof, to provide a separated solids stream and a separated liquids stream;
separating the separated liquids stream with a first separation device to provide a light emulsion phase and a heavy phase with suspended solids;
separating the heavy phase with suspended solids with a second separation device to provide a clarified heavy phase and a light phase concentrate, wherein the clarified heavy phase comprises 1% to 30% fat and 0.7% to 70% available oil;
reducing viscosity of the heavy phase with suspended solids by adding a chemical to the heavy phase with suspended solids; and
separating the light emulsion phase with a mechanical separation device to produce oil, heavy phase solids, and heavy phase liquids.
2. The method of claim 1 , wherein the first separation device is selected from the group consisting of a dissolved air floatation device, an open tank dissolved air floatation device, a dispersed air flotation device, an electrolysis flotation device, and combinations thereof.
3. The method of claim 1 , wherein the second separation device is selected from the group consisting of a dissolved air floatation device, an open tank dissolved air floatation device, and combinations thereof.
4. The method of claim 1 , further comprising adding a second non-condensable media to the separated liquids stream before the separation in the first separation device, wherein the second non-condensable media is selected from the group consisting of air, carbon dioxide, nitrogen, oxygen, and combinations thereof.
5. The method of claim 1 , wherein the chemical is selected from the group consisting of a polymer, a synthetic water-soluble polymer, a dry polymer, an emulsion polymer, a latex polymer, a dispersion polymer, a cationic flocculant, a cationic coagulant, an anionic flocculant, or an anionic coagulant, and combinations thereof.
6. The method of claim 1 , selecting the mechanical separation device is from the group consisting of a rotary drum vacuum filter, a dynamic cross-flow filtration device, a cross-flow filtration device, a filtering centrifuge, and combinations thereof.