Stage 5 of 15 / Calculation
Screen water demand and treatment recovery
Convert stoichiometric water into treated demand, raw-water withdrawal, reject and a buffer volume.
- Advanced
- 15 stages
- 14 min
- Process and energy systems
After this stage you can
- Calculate treated, raw and reject flows from recovery and the process allowance.
- Size a raw-water buffer in hours, not only in cubic metres.
- Record water quality as a category until an analysis exists.
The engineering
Treated water is reaction water plus a process-water allowance for rinsing, sampling and purification losses. Raw-water withdrawal is treated demand divided by treatment recovery. Reject is the difference.
The model does not size reverse osmosis, electrodeionisation or polishing. Existing EngiMetric water engines are real, but they are not bound to this electrolyzer envelope in this draft. A stack warranty still needs a verified ionic analysis.
Source status is a label: confirmed, limited, unavailable or unknown. A screening number with an unknown source is not a water strategy.
EngiMetric / green hydrogen educational workbench
Green Hydrogen Plant — Educational Screening Workbench
Loading the hydrogen project state...
Draft development workbench (noindex). Inputs are saved in this browser only. Calculations shown are screening/educational outputs from the existing model where implemented; missing or unsupported quantitative areas remain explicit. Completing stages records self-declared learning progress only — it is not quantitative engineering capability, not an OEM guarantee, and not industrial/project approval.
Stage
Inputs
Edit the screening inputs for this stage, then calculate. Values you enter are marked as user-entered in the local project state; defaults remain illustrative until replaced.
Screening results
Results come from the existing hydrogen screening model. Unsupported quantitative areas, missing evidence, and review requirements remain explicit; outputs are not certified design or approval decisions.
Process & balance context
This educational workbench presents stage-specific calculated outputs and limitations. Detailed interactive diagrams are not required for journey completion; use the stage results and assumptions panels to review boundaries, flows, energy, storage, and economics context.
Assumptions, limitations & review
Your deliverable for this stage
A water-withdrawal statement with recovery, reject and buffer.
Stage assumptions, limits and sources
Assumptions
- Raw-water density is 1,000 kg/m³.
- Recovery is an owned assumption, not a membrane projection.
Constraints
- Recovery must stay inside 1–99 %. A 100 % recovery is rejected.
Limitations
- No RO, EDI or pretreatment train is sized here.
- Reject disposal, discharge permits and ZLD options are not assessed.
Review status
- Needs engineering review
- Professional review is required before publication or use as a design basis.
Sources
- CIAAW - Standard Atomic Weightsstandards
- NIST Chemistry WebBook - Hydrogengovernment
- U.S. Department of Energy - Hydrogen Production: Electrolysisgovernment
- IEA - Global Hydrogen Review 2024, Hydrogen productionresearch institution
- IRENA - Electrolyser costsengineering org
Stage progress is stored in this browser only. The explanation and every limit on this page remain readable with JavaScript disabled; the calculators need it to run.
Stage kind: Calculation / Journey: green-hydrogen / Stage: water