Reaction proxies
Reaction Modeling
Reaction Network
Atom-balanced proxy reactions for sewage-to-fuel conversion, upgrading, aqueous polishing, treatment return load, and energy-credit checks.
Atom-balanced by automated checks
Non-reaction risk gates
Model boundary
These reactions are verification scaffolds, not complete mechanisms
The network checks atom accounting for representative proxies: AD conversion, fatty-acid hydrodeoxygenation, nitrogen removal, oxygenate cleanup, methane energy credit, and ammonia treatment burden. Real sludge HTL still needs measured product yields, kinetics, catalyst data, and sidestream testing.
AD baseline and aqueous polishing
Atom-balancedGlucose anaerobic digestion proxy
C6H12O6 -> 3 CH4 + 3 CO2
Represents the biological benchmark and the compatible aqueous-organic polishing route.
InterpretationBalanced proxy for carbohydrate-rich organics becoming biogas; useful as an AD reference, not proof of all sludge behavior.
ValidationMeasure BMP methane potential, methane slip, COD removal, and digestate/residual handling.
- C
- 0
- H
- 0
- O
- 0
HTL aqueous phase polishing
Atom-balancedAcetic acid methanogenesis proxy
C2H4O2 -> CH4 + CO2
Represents soluble organic acids in HTL process water that may be anaerobically converted to methane.
InterpretationBalanced methanogenesis proxy for readily biodegradable aqueous organics.
ValidationMeasure HTL aqueous COD, biodegradability, ammonia, toxicity, and BMP response.
- C
- 0
- H
- 0
- O
- 0
Hydrotreating
Atom-balancedPalmitic acid hydrodeoxygenation proxy
C16H32O2 + 3 H2 -> C16H34 + 2 H2O
Represents lipid-derived fatty acid upgrading into diesel-range paraffins.
InterpretationBalanced HDO proxy showing why hydrogen demand must be counted before fuel claims.
ValidationMeasure hydrogen demand, liquid yield, oxygen removal, catalyst exposure, and diesel-range product distribution.
- C
- 0
- H
- 0
- O
- 0
Hydrotreating
Atom-balancedOleic acid hydrogenation and hydrodeoxygenation proxy
C18H34O2 + 4 H2 -> C18H38 + 2 H2O
Represents unsaturated lipid upgrading and saturation toward hydrocarbon products.
InterpretationBalanced proxy for saturation plus deoxygenation of an unsaturated fatty acid.
ValidationMeasure hydrogen uptake, product saturation, oxygen removal, and storage stability.
- C
- 0
- H
- 0
- O
- 0
Hydrotreating
Atom-balancedPhenol hydrodeoxygenation proxy
C6H6O + H2 -> C6H6 + H2O
Represents oxygenated aromatic cleanup in sludge HTL biocrude.
InterpretationBalanced oxygen-removal proxy; real product slates may require additional hydrogenation.
ValidationMeasure phenolics, oxygenates, aromatic saturation, hydrogen demand, and product stability.
- C
- 0
- H
- 0
- O
- 0
Hydrotreating
Atom-balancedPyridine hydrodenitrogenation proxy
C5H5N + 5 H2 -> C5H12 + NH3
Represents nitrogen heterocycle cleanup, a major sludge-biocrude fuel-quality burden.
InterpretationBalanced HDN proxy that makes nitrogen removal and ammonia formation visible.
ValidationMeasure total nitrogen, nitrogen species, ammonia, catalyst exposure, and product nitrogen after hydrotreating.
- C
- 0
- H
- 0
- N
- 0
Hydrotreating
Atom-balancedIndole hydrodenitrogenation proxy
C8H7N + 7 H2 -> C8H18 + NH3
Represents heavier nitrogen aromatic cleanup in sludge HTL biocrude.
InterpretationBalanced proxy for severe denitrogenation demand from aromatic nitrogen compounds.
ValidationMeasure catalyst life, nitrogen removal, upgraded product nitrogen, and hydrogen intensity.
- C
- 0
- H
- 0
- N
- 0
HTL conversion and aqueous phase
Atom-balancedGlycine hydrothermal deamination proxy
C2H5NO2 + 2 H2O -> NH3 + 2 CO2 + 3 H2
Represents protein-derived nitrogen and gas-forming behavior during severe wet processing.
InterpretationBalanced simplified proxy for protein nitrogen release; it is a bookkeeping model, not a complete mechanism.
ValidationMeasure protein fraction, ammonia, gas composition, aqueous nitrogen, and carbon balance.
- C
- 0
- H
- 0
- N
- 0
- O
- 0
Energy and carbon ledger
Atom-balancedMethane combustion energy-credit check
CH4 + 2 O2 -> CO2 + 2 H2O
Represents the combustion side of biogas/RNG energy credit calculations.
InterpretationBalanced combustion check for energy and emissions accounting.
ValidationMeasure methane yield, methane slip, combustion use case, and displaced fossil energy.
- C
- 0
- H
- 0
- O
- 0
Wastewater treatment return load
Atom-balancedAmmonia nitrification oxygen-demand proxy
NH3 + 2 O2 -> HNO3 + H2O
Represents oxygen demand from ammonia returned to the treatment plant.
InterpretationBalanced proxy for nitrification oxygen burden; actual plant chemistry depends on pH and biology.
ValidationMeasure ammonia load, alkalinity, nitrification response, aeration energy, and permit limits.
- N
- 0
- H
- 0
- O
- 0
Not conversion reactions
Risk gates that stay outside the fuel-yield claim
PFAS is a contaminant gate, not a fuel-conversion molecule
PFOA/PFAS indicators should be screened and routed; this project should not assume PFAS conversion or destruction without dedicated analytical evidence.
Ash and metals are residual constraints
Inorganic ash, metals, and phosphorus species must be tracked through solids/residual streams rather than counted as fuel product.