NOVELTY - System comprises: (a) a transmission device configured to convey into a reaction chamber unprocessed organic-carbon-containing feedstock comprising free water, intercellular water, intracellular water, intracellular water-soluble salts, and at least some plant cells; (b) at least one reaction chamber comprising at least one entrance passageway, at least one exit passageway for fluid, at least one exit passageway for processed organic-carbon-containing feedstock, and at least three sections; and (c) a collection device.    USE - The system is useful for removing water and water-soluble salts from an organic-carbon-containing feedstock (claimed), where the processed organic-carbon-containing feedstock is useful to make several energy-producing products including liquid hydrocarbon fuels, solid fuel to supplant coal, and synthetic natural gas.    ADVANTAGE - The system: provides processed organic-carbon-containing feedstock with water content of less than 20 wt.%; decreases water-soluble salt content by at least 60% (preferably at least 75%) on a dry basis; reduces the cost of removing the water and the water-soluble salt to less than 60% that of the cost per weight of processed organic-carbon-containing feedstock from known mechanical, known physiochemical, or known thermal processes (claimed); reduces adverse results that occur with the subsequent use of the processed organic-carbon-containing feedstock; and minimizes energy consumption.    DETAILED DESCRIPTION - System comprises: (a) a transmission device configured to convey into a reaction chamber unprocessed organic-carbon-containing feedstock comprising free water, intercellular water, intracellular water, intracellular water-soluble salts, and at least some plant cells comprising cell walls that include lignin, hemicellulose, and microfibrils within fibrils; (b) at least one reaction chamber comprising at least one entrance passageway, at least one exit passageway for fluid, at least one exit passageway for processed organic-carbon-containing feedstock, and at least three sections comprising (b1) a wet fibril disruption section configured to interact with at least some of the lignin and hemicellulose between the fibrils to make at least some regions of the cell wall more susceptible to outflow by water-soluble salts, (b2) a vapor explosion section in communication with (b1) and at least configured to volatilize plant fibril permeable fluid through rapid decompression to penetrate the more susceptible regions of the cell wall so as to create a porous organic-carbon-containing feedstock with plant cell wall passageways for intracellular water and intracellular water-soluble salts to pass from the plant cell, and (b3) a compaction section in communication with (b2) and configured to compress the porous organic-carbon-containing feedstock between pressure plates configured to minimize formation of water-impermeable felt so as to permit the escape of intracellular water and intracellular water-soluble salt from the reaction chamber fluid exit passageway and to create processed organic-carbon-containing feedstock that passes out through its reaction chamber exit passageway; and (c) a collection device in communication with the reaction chamber and configured to gather the processed organic-carbon-containing feedstock having a water content of less than 20 wt.% and a water-soluble salt content that is decreased by at least 60% on a dry basis from that of the unprocessed organic-carbon-containing feedstock. INDEPENDENT CLAIMS are also included for:    (1) a process (P1) for removing water and water-soluble salts from organic-carbon-containing feedstock, comprising: (s1) inputting into a reaction chamber the unprocessed organic-carbon-containing feedstock; (s2) exposing the feedstock to hot solvent under pressure for a time at conditions specific to the feedstock to make some regions of the cell walls comprising crystallized cellulosic fibrils, lignin, and hemicellulose more able to be penetrable by water-soluble salts without dissolving more than 25% of the lignin and hemicellulose; (s3) removing the pressure so as to penetrate the more penetrable regions to create porous feedstock with open pores in the plant cell walls; and (s4) pressing the porous feedstock with conditions that include an adjustable compaction pressure versus time profile and compaction time duration, and between pressure plates configured to prevent felt from forming and blocking escape from the reaction chamber of intracellular and intercellular water, and intracellular water-soluble salts, and to create processed organic-carbon-containing feedstock; and    (2) a process (P2) for removing water and water-soluble salts from organic-carbon- containing feedstock, comprising: the steps (s1)-(s3) as above per se; and pressing the porous feedstock with conditions that include an adjustable compaction pressure versus time profile and compaction time duration, and between pressure plates configured to prevent felt from forming and blocking escape from the reaction chamber of intracellular and intercellular water, and intracellular water-soluble salts and to create processed organic-carbon-containing feedstock that has a water content of less than 20 wt.%, a water-soluble salt content that is decreased by at least 50.% on a dry basis that of unprocessed organic-carbon-containing feedstock, and a cost per weight of removing the water and water-soluble salt that is reduced to less than 60% of the cost per weight of similar water removal from known mechanical, known physiochemical, or known thermal processes.