Provided herein are methods, systems, and apparatuses for energy-efficient supercritical water oxidation of waste. The supercritical water oxidation processes and systems described herein may incorporate one or more of the following features: compression of large amounts of oxidant for plant-scale operations in an energy-efficient manner; the use of air as an oxidant; using reactor effluent to drive a turbine or other gas expander for energy recovery; and recovery of pressure and heat of reactor effluent. In some embodiments, the systems and methods are energy-neutral or energy-positive.

A hydrothermal liquefaction (HTL) system can comprise a biomass slurry source, a first pump in fluid communication with the slurry source and configured to pressurize a biomass slurry stream from the slurry source to a first pressure, a first heat exchanger in fluid communication with the first pump and configured to heat a slurry stream received from the first pump to a first temperature, a second pump in fluid communication with the first heat exchanger and configured to pressurize a slurry stream received from the first heat exchanger to a second pressure higher than the first pressure, a second heat exchanger in fluid communication with the second pump and configured to heat a slurry stream received from the second pump to a second temperature higher than the first temperature, and a HTL reactor configured to produce biocrude from a slurry stream received from the second heat exchanger.

The invention relates to a process for treating a waste lye of a lye scrub using an oxidation reactor (100), the waste lye and oxygen or an oxygen-containing gas mixture being introduced into the oxidation reactor (100) and steam being introduced into the oxidation reactor (100). It is provided that the steam is at least partially introduced by means of a steam feeding device (10), which has a cylindrical section (11) with a centre axis (12) and a wall (13), the centre axis (12) being aligned perpendicularly, a number of groups of openings (14) being formed in the wall, each of the groups comprising a number of the openings (14), and the number of openings (14) of each of the groups being arranged in one or more planes (15) that is or are in each case aligned perpendicularly to the centre axis (12). A corresponding installation and also a corresponding oxidation reactor (100) are likewise the subject of the present invention.

The invention relates to a process for treating a waste lye of a lye scrub using an oxidation reactor (100), the waste lye and oxygen or an oxygen-containing gas mixture being introduced into the oxidation reactor (100) and steam being introduced into the oxidation reactor (100). It is provided that the steam is at least partially introduced by means of a steam feeding device (10), which has a cylindrical section (11) with a centre axis (12) and a wall (13), the centre axis (12) being aligned perpendicularly, a number of groups of openings (14) being formed in the wall, each of the groups comprising a number of the openings (14), and the number of openings (14) of each of the groups being arranged in one or more planes (15) that is or are in each case aligned perpendicularly to the centre axis (12). A corresponding installation and also a corresponding oxidation reactor (100) are likewise the subject of the present invention.

Described herein is a reactor (1) includes: a first reaction volume (V1), a second reaction volume (V2), wherein: the first reaction volume (V1) is in fluid communication with an inlet port for an oxidizer agent (OX_IN), an inlet port for at least one first reactant (R1_IN) and an outlet port for at least one reaction product (P1_OUT), said second reaction volume (V2) is in fluid communication with an inlet port for at least one second reactant (R2_IN), an outlet port for at least one second reaction product (P2_OUT) and is furthermore in thermal exchange relationship with said first reaction volume (V1), wherein, during operation, in said first reaction volume (V1) an oxidation reaction occurs between said at least one first reactant and said oxidizer agent with the formation of said at least one first reaction product, and in said second reaction volume (V2) a gasification reaction occurs of said second reactant with the contribution of a thermal energy flow exchanged between the first and the second reaction volumes (V1, V2) with formation of said at least one second reaction product.

A hydrothermal treatment device (3) is a hydrothermal treatment device (3) performing hydrothermal treatment by heating high-water-content biomass, the hydrothermal treatment device (3) including a treatment container (21) that stores sludge, a sludge supply unit (22) that supplies the sludge to inside of the treatment container (21) such that a space (S) is formed in a vertical upper part of the treatment container (21), a stirrer (23) that is provided within the treatment container (21) and stirs stored matter such that counter flows in an up/down direction occur, and a heat transfer tube (24) that is disposed in a horizontal direction within the treatment container (21) and heats the sludge with heat of vapor flowing within the heat transfer tube (24).

There are disclosed processes and systems wet air oxidation systems and processes which provide for the combined treatment of a spent caustic with a spent material (e.g., spent carbon, spent biological material, or combinations thereof) to produce a regenerated spent material stream.

There are disclosed processes and systems wet air oxidation systems and processes which provide for the combined treatment of a spent caustic with a spent material (e.g., spent carbon, spent biological material, or combinations thereof) to produce a regenerated spent material stream.

A new wet oxidation process of wastes, specifically of mixtures of at least two, liquid (wastewaters) and dense (sludges), pumpable wastes is described. An apparatus useful for a wet oxidation process of this type is also described.

A new wet oxidation process of wastes, specifically of mixtures of at least two, liquid (wastewaters) and dense (sludges), pumpable wastes is described. An apparatus useful for a wet oxidation process of this type is also described.