Biochar
The invention provides for methods, devices, and systems for pyrolyzing biomass. A pyrolysis unit can be used for the pyrolysis of biomass to form gas, liquid, and solid products. The biomass materials can be selected such that an enhanced biochar is formed after pyrolysis. The biomass can be pyrolyzed under specified conditions such that a selected biochar core is formed. The pyrolysis process can form a stable biochar core that is inert and/or resistant to degradation. The biochar or biochar core can be functionalized to form a functionalized biochar or functionalized biochar core. Functionalization can include post-pyrolysis treatments such as supplementation with microbes or physical transformations including annealing and/or activation.
1. A method for producing a biochar core comprising the steps of:
introducing a biomass to a reactor; and
heating the biomass in the reactor in accordance with a predetermined set of operating parameters attuned to the biomass to produce a stable biochar core, wherein said biomass is heated i) at a heating rate between about 0.1° C./second and 50° C./second, and ii) at a heating time greater than about 0.001 days.
2. The method of claim 1 , wherein the biomass includes a plant derived material and/or an animal product.
3. The method of claim 1 , wherein the predetermined set of operating parameters includes a time-dependent temperature profile that corresponds to the selected type of biochar core.
4. The method of claim 1 , wherein the predetermined set of operating parameters includes an established temperature range and rate of temperature change that corresponds to the selected type of biochar core.
5. The method of claim 1 , further comprising at least one of blending the biochar core with organic matter, annealing, or activation.
6. The method of claim 1 , further comprising mixing the biochar with a supplement to produce a functionalized biochar core.
7. The method of claim 6 , wherein the supplement includes a microbe, a nutrient, a fertilizer, or any combination thereof.
8. The method of claim 7 , wherein the microbe is a rhizobacteria, a trichoderma, a mycorrhiza, or any combination thereof.
9. The method of claim 7 , wherein the supplement includes nutrients comprising nitrogen, phosphorus, potassium, selenium, cobalt, iron, or manganese.
10. The method of claim 1 , wherein said heating time is greater than 0.01 days.
11. The method of claim 1 , wherein a porosity of the stable biochar core is less than about nine-tenths of the total volume of the stable biochar core.
12. The method of claim 1 , wherein the stable biochar core has a surface area greater than about 300 m 2 per gram.
13. The method of claim 1 , further comprising supplementing said biomass with a feedstock having an ash content greater than about 5%.
14. The method of claim 1 , wherein said biomass is heated under oxygen deficient conditions.
15. A method for producing a biochar core comprising:
providing a biomass to a reactor; and
heating the biomass in the reactor to produce a stable biochar core that is resistant to degradation, wherein the biochar core has a rate of degradation that is less than 2.5% per year, and wherein said biomass is heated i) at a heating rate between about 0.1° C./second and 50° C./second, and ii) at a heating time greater than about 0.001 days.
16. The method of claim 15 , wherein the rate of degradation is less than 0.5% per year.
17. The method of claim 15 , wherein the rate of degradation is determined by measuring the loss of carbon.
18. A method for producing a biochar core comprising:
providing a biomass to a reactor;
heating the biomass in the reactor to produce a biochar core that has a biochar core carbon content greater than about 75% of the dry weight of the biochar, and wherein said biomass is heated i) at a heating rate between about 0.1° C./second and 50° C./second, and ii) at a heating time greater than about 0.001 days; and
combining the biochar core with a supplement to produce a functionalized biochar.
19. The method of claim 18 , wherein the biochar core has a volatile compound concentration of less than about 15 wt %.
20. The method of claim 18 , wherein the biomass has a biomass carbon content and the biochar core carbon content is greater than the biomass carbon content.
21. The method of claim 18 , wherein the biochar core has a specified nitrogen, phosphorus, or potassium content.
22. The method of claim 18 , wherein the biochar core comprises pores having a pore size range between about 5 to 50 microns.
23. The method of claim 18 , wherein the biochar core comprises pores having an average pore size of about 25 microns.
24. The method of claim 18 , wherein the biochar core that has a biochar core volatiles content less than about 30 wt % of the biochar.