BENEFICIATION OF COAL FOR STORAGE, TRANSPORTATION, AND GASIFICATION USING SUPERCRITICAL CARBON DIOXIDE

• Main Authors: TERRELL, Evan, WALTER, Joshua, KIM, Pyoungchung, GOODRICH, Benjamin
• Format: Patent
• Language: English; French; German
• Published: 16.08.2023
• Subjects: ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE ORUNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; CHEMISTRY; FIRELIGHTERS; FUELS; FUELS NOT OTHERWISE PROVIDED FOR; LIQUEFIED PETROLEUM GAS; LUBRICANTS; METALLURGY; NATURAL GAS; PEAT; PERFORMING OPERATIONS; PETROLEUM, GAS OR COKE INDUSTRIES; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BYSUBCLASSES C10G, C10K; TECHNICAL GASES CONTAINING CARBON MONOXIDE; TRANSPORTING

This document describes methods for pretreating coal to create either a dried coal or a char product that is stable in the outdoor environment and is more efficient as a feedstock for gasification or other processes than the original coal. Embodiments of the methods include pulverizing and pelletizing the coal, and pretreating the coal pellets to obtain a stable pellet of either dried coal or a stable pellet of chared coal (coal char). The pellets created by the described methods have undergone deoxygenation and carbonization improving their handling and storage properties and, in some cases, energy density. Pore structures within the pellets are stabilized physically and chemically so that the uptake of moisture into dry coal, that leads to internal heat generation, is greatly reduced. Chars are also, therefore, stable against transitions from a dry state to a wet state and less prone to self-ignition.