Methods and systems for producing aromatics and light olefins from a mixed plastics stream are described. The method may include feeding a plastic feedstock to a dechlorination operation to melt the plastic feedstock to release HCl and generate a liquid plastic stream; feeding the liquid plastic stream to a pyrolysis reactor, the pyrolysis reactor to generate hydrocarbon vapors; feeding the hydrocarbon vapors to an acid gas removal reactor with a solid inorganic alkali salt disposed within the reaction vessel to remove residual HCl and sulfur-containing compounds from the hydrocarbon vapors to generate a plastic derived oil; and feeding the plastic derived oil to a steam enhanced catalytic cracking reactor to generate a product stream comprising light olefins having a carbon number of C.sub.2-C.sub.4 and aromatics. The associated system for processing mixed plastics into aromatics and light olefins is also described.

Methods and systems for producing aromatics and light olefins from a mixed plastics stream are described. The method may include feeding a plastic feedstock to a dechlorination operation to melt the plastic feedstock to release HCl and generate a liquid plastic stream; feeding the liquid plastic stream to a pyrolysis reactor, the pyrolysis reactor to generate hydrocarbon vapors; feeding the hydrocarbon vapors to an acid gas removal reactor with a solid inorganic alkali salt disposed within the reaction vessel to remove residual HCl and sulfur-containing compounds from the hydrocarbon vapors to generate a plastic derived oil; and feeding the plastic derived oil to a steam enhanced catalytic cracking reactor to generate a product stream comprising light olefins having a carbon number of C.sub.2-C.sub.4 and aromatics. The associated system for processing mixed plastics into aromatics and light olefins is also described.

This invention provides compositions and methods that inhibit formation of alkenyl sulfide polymers and allow the hydrogen sulfide to be removed when scavenging hydrogen sulfide by reaction with aldehydes.

An integrated fuel combustion system with gas separation (adsorptive, absorptive, membrane or other suitable gas separation) separates a portion of carbon dioxide from a combustion gas mixture and provides for recycle of separated carbon dioxide to the intake of a fuel combustor for combustion. A process for carbon dioxide separation and recycle includes: admitting combustion gas to a gas separation system; sorbing a portion of carbon dioxide; recovering a flue gas stream depleted in carbon dioxide for release or use; desorbing the carbon dioxide from the gas separation system; admitting an oxidant stream into the gas separation system and forming a mixed oxidant stream; and recycling a portion of the mixed oxidant stream to an inlet of the fuel combustor.

An integrated fuel combustion system with gas separation (adsorptive, absorptive, membrane or other suitable gas separation) separates a portion of carbon dioxide from a combustion gas mixture and provides for recycle of separated carbon dioxide to the intake of a fuel combustor for combustion. A process for carbon dioxide separation and recycle includes: admitting combustion gas to a gas separation system; sorbing a portion of carbon dioxide; recovering a flue gas stream depleted in carbon dioxide for release or use; desorbing the carbon dioxide from the gas separation system; admitting an oxidant stream into the gas separation system and forming a mixed oxidant stream; and recycling a portion of the mixed oxidant stream to an inlet of the fuel combustor.

Intensification techniques are described for enhancing biocatalytic CO.sub.2 absorption operations, and may include the use of a rotating packed bed, a rotating disc reactor, a zig-zag reactor or other reactors that utilize process intensification. Carbonic anhydrase can be deployed in the high intensity reactor free in solution, immobilized with respect to particles that flow with the liquid, and/or immobilized to internals, such as packing, that are fixed within the high intensity reactor.

Intensification techniques are described for enhancing biocatalytic CO.sub.2 absorption operations, and may include the use of a rotating packed bed, a rotating disc reactor, a zig-zag reactor or other reactors that utilize process intensification. Carbonic anhydrase can be deployed in the high intensity reactor free in solution, immobilized with respect to particles that flow with the liquid, and/or immobilized to internals, such as packing, that are fixed within the high intensity reactor.

The present invention provides a device and method for sulphur cycle-based advanced denitrification of wastewater coupling autotrophic denitrification and heterotrophic denitrification, and belongs to the technical field of wastewater treatment. The unit generating hydrogen sulfide during the wastewater treatment process adopts a lye to absorb hydrogen sulfide; the absorbed sulfide is introduced into an anoxic tank that removes nitrate nitrogen through sulfur-based autotrophic denitrification; and the remaining organic matters in the anaerobic methane-producing reaction tank are subjected to heterotrophic denitrification in the anoxic tank, and the anoxic unit combines the sulfur-based autotrophic denitrification with the heterotrophic denitrification of organic matters. The coupling of sulfur-based autotrophic denitrification and heterotrophic denitrification strengthens the removal of nitrate nitrogen. The biogas desulfurization process system only absorbs hydrogen sulfide and uses the absorbed sulfide in an anoxic system to realize the recovery and utilization of sulfur.

The present invention provides a device and method for sulphur cycle-based advanced denitrification of wastewater coupling autotrophic denitrification and heterotrophic denitrification, and belongs to the technical field of wastewater treatment. The unit generating hydrogen sulfide during the wastewater treatment process adopts a lye to absorb hydrogen sulfide; the absorbed sulfide is introduced into an anoxic tank that removes nitrate nitrogen through sulfur-based autotrophic denitrification; and the remaining organic matters in the anaerobic methane-producing reaction tank are subjected to heterotrophic denitrification in the anoxic tank, and the anoxic unit combines the sulfur-based autotrophic denitrification with the heterotrophic denitrification of organic matters. The coupling of sulfur-based autotrophic denitrification and heterotrophic denitrification strengthens the removal of nitrate nitrogen. The biogas desulfurization process system only absorbs hydrogen sulfide and uses the absorbed sulfide in an anoxic system to realize the recovery and utilization of sulfur.

An integrated fuel combustion system with gas separation (adsorptive, absorptive, membrane or other suitable gas separation) separates a portion of carbon dioxide from a combustion gas mixture and provides for recycle of separated carbon dioxide to the intake of a fuel combustor for combustion. A process for carbon dioxide separation and recycle includes: admitting combustion gas to an adsorptive gas separation system contactor containing adsorbent material; adsorbing a portion of carbon dioxide; recovering a first product stream depleted in carbon dioxide for release or use; desorbing carbon dioxide from the adsorbent material and recovering a desorbed second product stream enriched in carbon dioxide for sequestration or use; admitting a conditioning and/or desorption fluid into the contactor and desorbing a second portion of carbon dioxide to recover a carbon dioxide enriched conditioning stream; and recycling a portion of the carbon dioxide enriched conditioning stream to an inlet of fuel combustor to pass through the fuel combustor for combustion.