01Experiment stage
Sample intake
Prove feedstock stability before conversion testing.
Measurements- Total solids
- Volatile solids
- Ash
- COD
- Nutrients
- Metals
Pass signalSample intake variability can be represented by low, base, and favorable model cases.
EscalationIf variability exceeds the envelope, split the feedstock into separate operating classes.
02Experiment stage
HTL screening
Find the practical conversion window for wet sewage sludge.
Measurements- Biocrude yield
- Gas yield
- Char yield
- Aqueous COD
- Energy duty
Pass signalHTL produces enough biocrude to keep the integrated base case alive after parasitic loads.
EscalationIf yield is weak, test severity, solids loading, and feed blending before abandoning the pathway.
03Experiment stage
Aqueous phase compatibility
Determine whether return streams destabilize wastewater treatment.
Measurements- COD removal
- Ammonia
- Nitrification response
- Toxicity screen
- BMP potential
Pass signalAqueous phase treatment stays inside permit, biology, and energy limits.
EscalationIf inhibition appears, test dilution, anaerobic polishing, adsorption, or offsite disposal routing.
04Experiment stage
Hydrotreating screen
Measure whether biocrude can become a credible fuel intermediate.
Measurements- Hydrogen demand
- Nitrogen removal
- Oxygen removal
- Liquid yield
- Stability
Pass signalHydrotreating closes the product-quality gap without erasing the energy or carbon case.
EscalationIf nitrogen remains high, assess staged severity, catalyst exposure, and alternate product markets.
05Experiment stage
Integrated comparison
Compare HTL, anaerobic digestion, and hybrid cases under the same boundary.
Measurements- Net energy
- Carbon intensity
- Avoided disposal
- Residuals
- Operating cost
Pass signalThe integrated case beats the AD reference case on facility value and carbon intensity.
EscalationIf the case is marginal, restrict scale-up to sites with high disposal cost or low-carbon energy.