Ammonium sulfate by direct neutralisation of ammonia with sulfuric acid

Tier 0 screening per tonne of crystalline ammonium sulfate from a continuous saturator-crystallizer: stoichiometry with US EPA dryer dust, no crystallizer heat (the heat of reaction evaporates the water, rejected to cooling water by an NBS enthalpy balance), an estimated dryer steam, electricity an ASSUMED analogue from solid ammonium nitrate. No flowsheet; not reviewed.

Calculation maturity: not assessedDesign maturity: Concept (research)Not independently reviewedFertilizersReport a problem with this process
Research outputNot engineering advice and not an approved design: do not use it for construction, operation or safety decisions. What this means

Tier 0 screening per tonne of crystalline ammonium sulfate from a continuous saturator-crystallizer: stoichiometry with US EPA dryer dust, no crystallizer heat (the heat of reaction evaporates the water, rejected to cooling water by an NBS enthalpy balance), an estimated dryer steam, electricity an ASSUMED analogue from solid ammonium nitrate. No flowsheet; not reviewed.

Capacity
per tonne of ammonium sulfate (the dataset's basis); no plant size

What goes in and out

In

  • AmmoniaFeedstock
  • Sulfuric acidFeedstock98.5 wt% acid, counted by mass of the acid; linked to sulfuric-acid-1 (lca/mappings.yaml)
  • WaterFeedstockmake-up to the centrifuge wash, closing the water balance (condensate returned, ASSUMED)

Out

Utilities: Electricity (ASSUMED analogue: solid ammonium nitrate, LVIC-AAF BREF Table 9.3 (25 to 60 kWh/t, midpoint)), Steam (dryer only, counted as heat delivered; our estimate with an ASSUMED dryer efficiency), Cooling water (heat of reaction rejected in the vapour condenser (kWh), from NBS enthalpies of formation)

Show in the process graph

Life cycle assessment

No footprint assessed yet; the process is part of the life-cycle inventory below.

In the open LCI database (cheme-as-code-atlas-preview-a3c52e4) as Ammonium sulfate, crystalline, fertilizer grade Preliminary.

Download it for Brightway, openLCA and other tools.

In the LCI database: system model, datasets and KPIs against the benchmarks

In the LCI database

Status
Preliminary 1 unmapped exchange. Some exchanges have no background mapping yet: they are exported unlinked and count no burden, so the inventory is incomplete.
System model
attributional, cut-off (methodology 1.1.0)
Allocation
mass (single-output, from default) · product:ammonium-sulfate 100 %
Allocation findings
none
Change report
Not available: this build has no change report against an earlier release.
Dataset pages
Ammonium sulfate, crystalline, fertilizer grade Preliminary

KPI benchmark positions

KPIValueReference rangePosition
Particulate to air from the ammonium sulfate dryer per t of product– kg/t0 to 0.15 kg/t
US EPA (1980) Standards of Performance for New Stationary Sources; Ammonium Sulfate Manufacture. Federal Register 45 (220): 74846, 12 November 1980; 40 CFR 60 subpart PP (government)
not evaluated
Electricity per t of ammonium sulfate
No open source with an electricity figure for ammonium sulfate found (2026-11-05). Read: US EPA AP-42 section 8.4 and its background report (emissions only), the 1980 NSPS (control equipment energy only as a share of plant energy, no plant figure), the GEA Messo PT brochure (2010; pump power only as a ratio between crystallizer types), the UNIDO fertilizer manual chapter VIII (no utility figures), the LVIC-AAF BREF 2007 (no ammonium sulfate chapter). Not readable: Crystallization of Ammonium Sulphate, State of the Art and New Developments (ResearchGate, HTTP 403); CRU/BC Insight articles (paywalled). A web search (2026-11-05) found only university plant-design theses that state an installed electrical load in kVA. That is not consumption, so they were not used. The dataset's value is an ASSUMED analogue, the midpoint of the solid AN range of LVIC-AAF BREF Table 9.3 (25 to 60 kWh/t), not a check.
– kWh/tnot availablenot evaluated
Steam, as heat delivered, per t of ammonium sulfate
No open figure for the heat of an ammonium sulfate plant found (2026-11-05), in the sources listed under as-specific-electricity. GEA (2010, PDF p. 4) and UNIDO chapter VIII state qualitatively that a reaction crystallizer with concentrated reactants needs no external heat for evaporation; the dataset's value is the dryer only, our estimate with an ASSUMED efficiency. An evaporative (by-product) crystallizer is heated with steam and its energy is the main running cost (GEA 2010, PDF p. 6), so a figure for that route would not apply here.
– kWh/tnot availablenot evaluated

Maturity and review

Design maturity Concept (claimed): An idea or first flowsheet; numbers are rough. No independent engineering review yet. Automated checks passing is not a review.

Calculation maturity, from the checked evidenceNot assessed

The process has no maturity report (cheme maturity, checks/maturity.json), so no calculation maturity is established.

No level shownThe design maturity (Concept) is the manifest's claim, not evidence. A level appears here once the process's repository holds a current report from cheme maturity --write.

Artifact completeness

Which deliverables exist. They never raise a calculation maturity level: a drawing from unchecked numbers is still unchecked.

Not reported without a maturity report.

Independent review

Not independently reviewed

No independent engineering review yet. Automated checks passing is not a review.

Set by people only. Reaching a calculation maturity level or passing automated checks is not an independent review or an approval.

Where the evidence comes from
Report
processes/ammonium-sulfate-1/checks/maturity.json (not in the library)
Method
How ChemE-as-Code checks the levels (requirement by requirement)

Open items

0 open items · 0 closed

New action itemNew engineering holdNew technical queryNew design changeAll issues

Sources

Library version
a3c52e4 (process last changed in a3c52e4)
Data
Catalog record (JSON) · CC-BY-4.0
Files
View the files on GitHub · change history and authors

References

How to cite

For the data, cite the Process Atlas paper; for the platform that builds and checks it, the ChemE-as-Code paper.

Schweidtmann, A. M. & Weber, J. M. (2026, in preparation). Process Atlas: an open, git-native, reproducible library and life cycle inventory of chemical processes (working title).

For this process: "Ammonium sulfate by direct neutralisation of ammonia with sulfuric acid", ChemE-as-Code process library, version a3c52e4.

BibTeX
@unpublished{schweidtmann_process_atlas,
  author = {Schweidtmann, Artur M. and Weber, Jana M.},
  title = {{Process Atlas: an open, git-native, reproducible library and life cycle inventory of chemical processes (working title)}},
  year = {2026},
  url = {https://atlas.cheme-as-code.org},
  note = {in preparation}
}

Schweidtmann, A. M. (2026). ChemE-as-Code: An Open-Source Platform for Agentic AI in Chemical Engineering. arXiv:2611.07947. https://doi.org/10.48550/arXiv.2611.07947

BibTeX
@misc{schweidtmann_cheme_as_code,
  author = {Schweidtmann, Artur M.},
  title = {{ChemE-as-Code: An Open-Source Platform for Agentic AI in Chemical Engineering}},
  year = {2026},
  eprint = {2611.07947},
  archivePrefix = {arXiv},
  doi = {10.48550/arXiv.2611.07947},
  url = {https://arxiv.org/abs/2611.07947}
}