Exhaust Gas Handling TRIZ Cases

Hydrogen reduction produces highly metallized DRI pellets with controlled porosity, lowering oxidation risk while improving strength for handling and storage.

Nitrogen-assisted hydrogen reduction in a shaft furnace cuts gas intensity and reuses reduced-iron heat to improve thermal efficiency.

By mixing hydrogen-depleted tail gas with smelting offgas, this case raises fuel value for process heat while conserving hydrogen and cutting CO2 emissions.

Recirculated electric furnace and converter gases are purified and reused as reduction gas to cut fresh gas demand and improve steelworks efficiency.

Counterflow hydrogen cooling and top-gas feedback reduce reducing-gas heating demand while keeping DRI outlet temperature and metallization within limits.

Magnetic separation recovers iron-nitrogen fractions from ammonia-based iron ore reduction for use in magnets, alloy additives, and less waste.

Cold or quenched gas injected above the main reduction zone slows early iron oxide reduction, cutting fines while preserving shaft furnace throughput.

Nitrogen carries sensible heat in a hydrogen-rich shaft furnace gas mix, lowering blow temperature and reducing hydrogen waste in iron oxide reduction.

Closed-loop furnace gas reuse balances methane synthesis and reforming to cut CO2 emissions and reduce external fuel gas demand.

A membrane reactor converts water vapor back to hydrogen, enabling closed-loop direct reduced iron support production with lower energy use.

Using oxygen-rich injection and non-nitrogen carrier gases, this case raises smelting off-gas CO2 to 80-89% for direct CCS or CCU.

Direct then indirect electric heating raises reducing gas toward reaction temperature, supporting lower-emission DRI operation.

Separating discharged reduction gas yields hydrogen for external use while supporting carbon control in sponge iron.

Hydrogen is separated from coke oven gas for DRI reduction, while residual gas enters the transition section to set carbon at 0.5–3 wt.%.

Impurity-sensitive catalysts hinder DRI production; plasma-cracked methane supplies hydrogen, while top-gas recycling supports CO2-neutral reduction.

Pressure sensors match charge-vessel and shaft pressures, limiting inert-gas dilution and costly flaring during sponge iron production.

CO2 gas refines molten iron while tracking generated CO solves endpoint detection challenges.

Staged compression of recycled top gas minimizes pressure energy dissipation, enhancing the energy balance and output rates in iron oxide reduction.

A secondary circuit recovers unreacted hydrogen gas from a direct reduction shaft, preventing energy loss and minimizing NOx emissions.

Integrates electrolysis and gas shift reactors to produce hydrogen on-site for direct reduced iron manufacturing.

Controlled gas velocity prevents ore scattering in fluidized beds while packed-bed reactors handle larger grains for stable molten iron production.

Circulates CO2 and H2O gases between DRI processing and molten iron refining to optimize decarbonization.

Condensing water vapor from off-gases recycles liquid for electrolysis, reducing fresh water consumption in iron oxide treatment.

Reforming discharge gas with reduced iron catalyst generates reformed reducing gas, lowering nitrogen content and coal consumption in molten iron manufacturing.

Segmented carbon addition across electric furnace and LD-vessel stages resolves low-carbon hot metal contradictions in hydrogen-based steelmaking.

A two-step electric gas heating system segments reduction gas temperature control to prevent carbon deposition on heater elements.

Segmented electric heating blocks allow steam injection to remove carbon deposits without interrupting direct reduced iron production.

Solid oxide electrolyzer cell generates hydrogen and steam from water using waste heat from direct reduction furnaces.

A flash ironmaking drop tube furnace uses an induction-heated graphite susceptor to heat fine iron ore particles in a cocurrent gas flow.

A Y-type entrained flow bed mixes iron ore and coal powder to produce crude syngas and molten iron directly.

Activator means divert fumes to eliminate cold zones and prevent aperture obstructions, ensuring homogeneous heating while reducing maintenance frequency.

Fume diverter channel forces gas flow through a labyrinthine path to precipitate suspended particles onto the conveyor bottom.

Recycles process gases from iron melt production to carburize sponge iron, maintaining carbon content while using hydrogen-rich reduction gases.

Feeding loose unagglomerated iron ore with biomass reductant into a reduction furnace eliminates pelletizing equipment costs while producing synthetic gas.

Injecting heated methanol eliminates external reforming steps while carburizing sponge iron.

A rotary hearth furnace adjusts non-heating zone openings to control gas flow rates and position exhaust diverging points precisely.

Exhaust gas transfers sensible heat to ore feeding gas, drying fine ores and reducing energy consumption in reduced iron manufacturing.

Oxidizing molten slag above 1400°C removes sulfur to prevent reintroduction into pig iron production.

A roll press machine compresses dried steelmaking sludge with desulfurization and ladle furnace dust using molasses binder to form solid briquettes.

Liquid bio-oil reduces gas diffusion limits in iron ore, enabling 10-20 times faster reaction rates and smaller furnace designs.

Pre-treated make-up gas eliminates carbon deposition and catalyst carburization in direct reduced iron reactors.

Countercurrent saturator mixing controls water vapor to reduce carbon deposits and enhance hydrogen-to-carbon monoxide ratio.

Segmented stationary walls reduce dust emissions while maintaining maintenance access to the cooler grate surface.

Recycled top gas from fluidized bed furnaces cuts CO2 emissions while maintaining iron production.

An ejector recycles cooling gas using high-pressure natural gas as motive fluid, replacing compressors to cut capital and operational costs.

A hydrogen sponge iron reduction system recycles unreacted gas through a primary and secondary circuit to optimize energy use.

An integrated cooling zone within the reactor vessel produces cold DRI, eliminating separate cooling vessels and reducing capital costs.

A high-pressure shaft furnace produces cast iron and syngas using low-grade coal gasified with preheated oxygen.

Electrical plasma heating raises precursor gas temperature, avoiding soot formation and preserving reduction potential.

Dual make-up gas strategy regulates DRI carbon content via separate reforming and heating pathways, resolving energy efficiency trade-offs.

Segmented iron ore processing reduces carbon emissions by combining fluidized bed partial reduction with submerged arc furnace melting.