Methods and systems are provided for two-stage treatment of contaminated particulate material, such as soil, sediment, and/or sludge. The methods and systems utilize a thermal desorption process combined with a smoldering combustion process. The contaminated particulate material is first exposed to thermal desorption at high temperatures (e.g., greater than 150° C.) to form a heated contaminated particulate material. Next, a smoldering combustion process is initiated by introducing a combustion-supporting gas. The combined process can take place in the same or different treatment units. Treating the particulate material with a thermal desorption process prior to a smoldering combustion process enhances the completeness and throughput compared to operating these processes separately.

A method and an apparatus for treating comminuted waste material the method comprising: •a) heating comminuted waste material in a heating chamber (28) using one or more heating means (40a-f) to generate a combustible gas •b) measuring or determining the temperature in the heating chamber; •c) comparing the measured or determined temperature in the heating chamber ((28) with a predetermined temperature range; and •d) adjusting the amount of heat applied by the one or more heating means (40a-f) to the heating chamber (28) to maintain the temperature in the heating chamber within the predetermined temperature range.

The invention provides a system for pyrolysing organic waste. The system comprises a conical housing (4) configured to temporarily, substantially hermetically, enclose the waste and a mixing device provided with a drive shaft rotatably mounted relative to the housing and a conical mixing body (25) configured inside the housing to fluidise the waste, which mixing body fixedly attached substantially does not touch the housing. The system further comprises heating means (24) for heating the side wall of the housing. This system makes it possible to carry out the processing of organic waste in a batch process. The mixing body prevents a portion of the waste from sticking together by fluidising the waste and keeping it fluidised, whereby the heat generated by the heating means can gradually spread through the waste inside the housing.

Improved processes and systems are disclosed for producing renewable hydrogen suitable for reducing metal ores, as well as for producing activated carbon. Some variations provide a process comprising: pyrolyzing biomass to generate a biogenic reagent comprising carbon and a pyrolysis off-gas; converting the pyrolysis off-gas to additional reducing gas and/or heat; reacting at least some of the biogenic reagent with a reactant to generate a reducing gas; and chemically reducing a metal oxide in the presence of the reducing gas. Some variations provide a process for producing renewable hydrogen by biomass pyrolysis to generate a biogenic reagent, conversion of the biogenic reagent to a reducing gas, and separation and recovery of hydrogen from the reducing gas. A reducing-gas composition for reducing a metal oxide is provided, comprising renewable hydrogen according to a hydrogen-isotope analysis. Reacted biogenic reagent may also be recovered as an activated carbon product. Many variations are disclosed.

The invention provides a method of sequential pyrolysis and carbon deposition to produce a composite carbonaceous product, the method comprising: a pyrolysis process step comprising pyrolyzing a pyrolyzable organic feed at a pyrolysis temperature in a first reaction zone in the presence of a non-oxidising gas to produce hot char and pyrolysis gas, wherein the pyrolysis gas and the non-oxidising gas combine to form a gas mixture; discharging the gas mixture from the first reaction zone to a combustion zone and combusting at least a portion of the pyrolysis gas therein, wherein heat produced by the combusting of the pyrolysis gas is transmitted from the combustion zone to the first reaction zone to provide at least a portion of the heat of pyrolysis; and a decomposition process step comprising contacting a hydrocarbon-rich organic gas with the hot char directly after its production in the pyrolysis process step, wherein the hydrocarbon-rich organic gas catalytically decomposes on the hot char at a decomposition temperature which is higher than the pyrolysis temperature, thereby producing gaseous decomposition products comprising hydrogen and a composite carbonaceous material comprising the char with carbon deposits thereon.

Improved processes and systems are disclosed for producing renewable hydrogen suitable for reducing metal ores, as well as for producing activated carbon. Some variations provide a process comprising: pyrolyzing biomass to generate a biogenic reagent comprising carbon and a pyrolysis off-gas; converting the pyrolysis off-gas to additional reducing gas and/or heat; reacting at least some of the biogenic reagent with a reactant to generate a reducing gas; and chemically reducing a metal oxide in the presence of the reducing gas. Some variations provide a process for producing renewable hydrogen by biomass pyrolysis to generate a biogenic reagent, conversion of the biogenic reagent to a reducing gas, and separation and recovery of hydrogen from the reducing gas. A reducing-gas composition for reducing a metal oxide is provided, comprising renewable hydrogen according to a hydrogen-isotope analysis. Reacted biogenic reagent may also be recovered as an activated carbon product. Many variations are disclosed.

Improved processes and systems are disclosed for producing renewable hydrogen suitable for reducing metal ores, as well as for producing activated carbon. Some variations provide a process comprising: pyrolyzing biomass to generate a biogenic reagent comprising carbon and a pyrolysis off-gas; converting the pyrolysis off-gas to additional reducing gas and/or heat; reacting at least some of the biogenic reagent with a reactant to generate a reducing gas; and chemically reducing a metal oxide in the presence of the reducing gas. Some variations provide a process for producing renewable hydrogen by biomass pyrolysis to generate a biogenic reagent, conversion of the biogenic reagent to a reducing gas, and separation and recovery of hydrogen from the reducing gas. A reducing-gas composition for reducing a metal oxide is provided, comprising renewable hydrogen according to a hydrogen-isotope analysis. Reacted biogenic reagent may also be recovered as an activated carbon product. Many variations are disclosed.

Improved processes and systems are disclosed for producing renewable hydrogen suitable for reducing metal ores, as well as for producing activated carbon. Some variations provide a process comprising: pyrolyzing biomass to generate a biogenic reagent comprising carbon and a pyrolysis off-gas; converting the pyrolysis off-gas to additional reducing gas and/or heat; reacting at least some of the biogenic reagent with a reactant to generate a reducing gas; and chemically reducing a metal oxide in the presence of the reducing gas. Some variations provide a process for producing renewable hydrogen by biomass pyrolysis to generate a biogenic reagent, conversion of the biogenic reagent to a reducing gas, and separation and recovery of hydrogen from the reducing gas. A reducing-gas composition for reducing a metal oxide is provided, comprising renewable hydrogen according to a hydrogen-isotope analysis. Reacted biogenic reagent may also be recovered as an activated carbon product. Many variations are disclosed.

Improved processes and systems are disclosed for producing renewable hydrogen suitable for reducing metal ores, as well as for producing activated carbon. Some variations provide a process comprising: pyrolyzing biomass to generate a biogenic reagent comprising carbon and a pyrolysis off-gas; converting the pyrolysis off-gas to additional reducing gas and/or heat; reacting at least some of the biogenic reagent with a reactant to generate a reducing gas; and chemically reducing a metal oxide in the presence of the reducing gas. Some variations provide a process for producing renewable hydrogen by biomass pyrolysis to generate a biogenic reagent, conversion of the biogenic reagent to a reducing gas, and separation and recovery of hydrogen from the reducing gas. A reducing-gas composition for reducing a metal oxide is provided, comprising renewable hydrogen according to a hydrogen-isotope analysis. Reacted biogenic reagent may also be recovered as an activated carbon product. Many variations are disclosed.

Methods and systems are provided for two-stage treatment of contaminated particulate material, such as soil, sediment, and/or sludge. The methods and systems utilize a thermal desorption process combined with a smoldering combustion process. The contaminated particulate material is first exposed to thermal desorption at high temperatures (e.g., greater than 150 C.) to form a heated contaminated particulate material. Next, a smoldering combustion process is initiated by introducing a combustion-supporting gas. The combined process can take place in the same or different treatment units.