NOVELTY - Producing (M1) a high-carbon biogenic reagent involves: optionally drying carbon-containing feedstock comprising biomass to remove portion of moisture contained within feedstock; optionally deaerating feedstock; in a pyrolysis zone, pyrolyzing feedstock in presence of inert gas for at least 10 minutes and at 250-700 degrees C, to generate hot pyrolyzed solids, condensable vapors, and non-condensable gases; separating condensable vapors and non-condensable gases from hot pyrolyzed solids; cooling hot pyrolyzed solids in presence of inert gas and recovering high-carbon biogenic reagent.    USE - For producing high-carbon biogenic reagent (claimed) that are suitable for a variety of commercial applications e.g. as a reactant, for reducing metal oxides to metals during processing; as a fuel, to provide heat for processing and as a component of the final metal alloy; as carbon addition product for metals production; as a carbon addition product for production of carbon steel or another metal alloy comprising carbon; as carbon electrodes; as an electrode (e.g. anode) material suitable used in aluminum production; in carbon electrodes e.g. in batteries, fuel cells, capacitors, and other energy-storage or energy-delivery devices e.g. lithium-ion battery; as catalyst supports used in catalyzed chemical reactions, such as mixed-alcohol synthesis from syngas using sulfided cobalt-molybdenum metal catalysts supported on a carbon phase, or iron-based catalysts supported on carbon for Fischer-Tropsch synthesis of higher hydrocarbons from syngas; as activated carbon products used in liquid and gas-phase applications, including water treatment, air purification, solvent vapor recovery, food and beverage processing, and pharmaceuticals.    ADVANTAGE - The method is continuous or semi-continuous. The monitoring and controlling the method improves process energy efficiency, product attribute associated with the high-carbon biogenic reagent such as carbon content, energy content, structural integrity, or mechanical strength. The method is energy-efficient and with non-polluting; is economic; scales up such a process for continuous commercial-scale production of high-quality carbon, while manages the energy balance and controls emissions. The pyrolysis condition is selected to maintain the structural integrity or mechanical strength of the high-carbon biogenic reagent relative to the feedstock, when it is desired to do so for a certain product application. The pyrolysis can at least partially dehydrate the feedstock. The pyrolysis removes greater than 50%, 75%, 90%, 95%, 99% of the water from the feedstock. The prepared high-carbon biogenic reagent is not only environmentally superior, but also functionally superior from a processing standpoint because of greater purity. The method can result in significantly lower emissions of CO, CO2, NOx, SO2, and hazardous air pollutants compared to the coking of coal-based products necessary to prepare them for use in metals production. The prepared high-carbon biogenic reagent is used in place of coal or coke also significantly reduces environmental emissions of SO2, hazardous air pollutants, and mercury. Also, because of the purity of these high-carbon biogenic reagents (including low ash content), the biogenic reagents have the potential to reduce slag and increase production capacity in batch metal-making processes.    DETAILED DESCRIPTION - Producing (M1) a high-carbon biogenic reagent involves:    (A) providing a carbon-containing feedstock comprising biomass;    (B) optionally drying the feedstock to remove at least a portion of moisture contained within the feedstock;    (C) optionally deaerating the feedstock to remove at least a portion of interstitial oxygen, if any, contained with the feedstock or the dried feedstock;    (D) in a pyrolysis zone, pyrolyzing the feedstock in the presence of inert gas for at least 10 minutes and with a pyrolysis temperature selected from 250-700 degrees C, to generate hot pyrolyzed solids, condensable vapors, and non-condensable gases;    (E) separating at least a portion of the condensable vapors and at least a portion of the non-condensable gases from the hot pyrolyzed solids;    (F) in a cooling zone, cooling the hot pyrolyzed solids, in the presence of the inert gas for at least 5 minutes and with a cooling-zone temperature less than the pyrolysis temperature, to generate warm pyrolyzed solids;    (G) in an optional cooler that is separate from the cooling zone, cooling the warm pyrolyzed solids to generate cool pyrolyzed solids; and    (H) recovering a high-carbon biogenic reagent comprising at least a portion of the cool pyrolyzed solids.