Ground calcium cyanamide fertilizer from carbide nitridation

1. Scope and Applicability

This method addresses ground, ungranulated calcium cyanamide fertilizer made by nitriding purchased technical calcium carbide with separated gaseous nitrogen, followed by cooling, grinding and bulk delivery at the factory gate. Technical product contains actual residual lime, carbon and carbide; it is not assumed to be pure CaCN2. The producer original distinguishes powder from pearled product (alzchem-route). The chosen foreground starts at purchased carbide and nitrogen; it does not copy the producer's integrated site boundary.

Exclude pearled or nitrate-enriched formulations, aqueous cyanamide, urea/AN/CAN, ammonium sulphate, arbitrary nitrogen-fertilizer blends, lime-urea synthesis, and pure reagent CaCN2. No field efficacy, avoided liming credit, soil emissions or fertilizer-use advantage is quantified. A broader classification label does not establish one collective manufacturing process.

2. Product Category Identity

Field	Value
canonical_pcr_id	pcr.other-transportable-goods-except-metal-products-machinery-and-equipment.basic-chemicals.ground-calcium-cyanamide-fertilizer
classification_refs	CPC 3.0 34619, proposed narrower only; independently confirm residual membership.
covered_products	Bulk ground technical calcium cyanamide fertilizer; declared actual composition.
excluded_products	Granulated/enriched mixtures; aqueous cyanamide; reagent grade; other nitrogen fertilizers.
representative_product	Ground lime-nitrogen fertilizer, not a fixed commercial SKU or assay.
production_route	Purchased carbide + separated gaseous N2; nitridation, cooling, grinding and bulk dispatch.
market_state	Unpackaged powder; net as-dispatched mass at declared moisture.

3. Reference Flow

Field	Value
What	Supply declared ground calcium cyanamide fertilizer at factory gate.
How much	1 kg net as-dispatched powder, excluding transport containers.
How well	Lot certificate declares total N, cyanamide-N, other N species, moisture, residual carbide, free lime/carbon and particle size; no universal assay.
How long or cycle	One declared production campaign and factory-gate delivery; no agronomic service duration.
reference_flow_link	finished_powder

Field	Value
Reference amount	1
Reference product flow	Nitrogen fertiliser fc45dbd4-a3a4-420d-849b-a370b5261a84; broad identity restricted here to bulk ground calcium cyanamide fertilizer.
Reference flow property	Mass 93a60a56-a3c8-11da-a746-0800200b9a66
Reference unit group	Units of mass 93a60a57-a4c8-11da-a746-0800200c9a66
Reference unit	kg
Required qualifiers	Route; bulk powder state; actual SKU/grade and lot; product versus N mass; total N and N species; moisture; residual CaC2; free lime/carbon; particle size; site and period; supplier background bases; electricity geography/voltage.

Missing qualifiers make the foreground reference incomplete. The N content is a separately reported property, not a replacement reference denominator.

4. Measurement and Unit Rules

rule_id	Applies to	Required property	Required unit	Rule
reference_mass	finished_powder	Mass 93a60a56-a3c8-11da-a746-0800200b9a66	kg	Use net as-dispatched powder mass; collect using cp_product; subtract transport tare. Keep moisture and nitrogen assay on the same lot basis.
nutrient_basis	finished_powder	Mass	kg	Record kg N separately using measured lot mass and measured N mass fraction. Never substitute kg N for kg fertilizer or assume pure CaCN2 conversion.
gas_basis	nitrogen_in	Mass	kg	Use calibrated mass delivery, or volume with documented T/P, wet/dry basis, composition, compressibility and supplier reference conditions; no database density default.
power_basis	electricity_in	Net calorific value	MJ	Preserve actual metered kWh and document electrical-energy conversion 1 kWh = 3.6 MJ. NCV is the platform property label, not a combustion assumption.

5. System Boundary

Boundary Abstraction

Field	Value
declared_starting_condition	Purchased technical calcium carbide and separated gaseous nitrogen received at nitridation plant.
starting_condition_role	foreground_start
product_classification_scope	Ground calcium cyanamide subset; no whole-leaf manufacturing claim.
recursive_input_rule	Same-category purchased powder remains an external input with its own upstream dataset; separate regrinding from nitridation; never recurse indefinitely.
upstream_dataset_requirement	Link compatible carbide, N2, electricity and water providers; include their upstream burdens once. Integrated carbide or air separation requires separately measured expansion, not omission or duplicated purchased inputs.
disclosure	Disclose site, period, stock changes, operating/upset states, utility supply, dust recycling, purge destinations and upstream exclusions.

rule_id	applies_to	rule	source_ids
boundary_route	foreground	Include receipt, grinding of carbide, nitridation, cooling, product grinding, extraction, indirect cooling if installed, waste transfer and bulk dispatch as one measured foreground unit. Keep stage meters and material balances.	alzchem-route, jrc-cww-2016
boundary_upstream	carbide_in	Carbide manufacture is an upstream electrothermal process. BREF carbide figures are not nitridation defaults. Do not model upstream recovered CO as a nitridation product or add upstream CO2 again.	jrc-lvic-s-2007
boundary_complete	foreground	Maintain a species/utility/residue screen. Additional actual fuel, chemical, packaging, pollutant or cooling additive requires its own atomic row and verified identity before a complete dataset is claimed; do not infer absence from this draft list.	jrc-cww-2016

6. Process Inventory Structure

Process Map

process_id	process_name	inclusion	inclusion_condition	role	quantitative_reference
nitridation	Carbide nitridation and powder finishing	required	Declared purchased-carbide powder route	foreground	finished_powder

Process: Carbide nitridation and powder finishing (nitridation)

Inputs

Product flows

Calcium carbide for nitridation (carbide_in)

Weigh technical calcium carbide charged; assay CaC2, free lime, carbon, moisture and impurities. No Bayer-route UUID is assigned.

• Selected flow: Calcium carbide for nitridation
• Flow property / unit: Mass / kg
• Amount rule: Measured attributable campaign exchange / accepted net powder kg; collect using cp_material
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_material
• Sources: alzchem-route, jrc-lvic-s-2007

Nitrogen (nitrogen_in)

Meter delivered gaseous N2 from air separation, including purge and unreacted gas in the nitrogen balance; reconcile measured mass or documented gas-state conversion.

• Selected flow: Nitrogen 67bb2ea6-2fd8-43c5-b227-bca12040b773
• Flow property / unit: Mass / kg
• Amount rule: Measured attributable campaign exchange / accepted net powder kg; collect using cp_material
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_material
• Sources: alzchem-route

Alternating current (electricity_in)

Meter all reactor heating, grinding, cooling circulation, extraction and bulk handling. Selected identity applies only to China grid-average customer-side 1-35kV; verify actual supply.

• Selected flow: Alternating current 3d76981f-964a-4865-b588-0e067a2a1163
• Flow property / unit: Net calorific value / MJ
• Amount rule: Measured attributable campaign exchange / accepted net powder kg; collect using cp_energy
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_energy
• Sources: alzchem-route

Water, tap (cooling_water_in)

Meter purchased tap-water makeup for indirect cooling only if installed; exclude internal circulation. Record actual water source and measured density for volume conversion.

• Selected flow: Water, tap 6a8b6455-e9bb-4cb9-81ea-5e83413d5fe1
• Flow property / unit: Mass / kg
• Amount rule: Measured attributable campaign exchange / accepted net powder kg; collect using cp_water
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_water
• Sources: jrc-cww-2016

Waste flows

Elementary flows

Outputs

Product flows

Nitrogen fertiliser (finished_powder)

Accepted ground calcium cyanamide fertilizer powder measured under cp_product. The selected broad nitrogen-fertilizer identity is physically inclusive, formulation unspecified; it does not establish pure CaCN2 or a provider. Source Fertilizer,N quantities and their unclarified nutrient/product mass basis are not adopted. One foreground output preserves actual stage measurements.

• Selected flow: Nitrogen fertiliser fc45dbd4-a3a4-420d-849b-a370b5261a84
• Flow property / unit: Mass / kg
• Amount rule: 1 kg
• Value mode: fixed_value
• Specificity: product_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: source_rule
• Collection protocol: cp_product
• Sources: alzchem-route

Waste flows

Dust (dust_out)

Weigh collected cyanamide-bearing dust only when transferred to an external waste receiver; record composition, residual carbide, moisture and acceptance. Internally returned dust remains internal, not an emission.

• Selected flow: Dust 2a6c9b60-a075-45ec-b611-c3b4dd255935
• Flow property / unit: Mass / kg
• Amount rule: Measured attributable campaign exchange / accepted net powder kg; collect using cp_residue
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_residue
• Sources: jrc-cww-2016

Indirect cooling-water purge to off-site treatment (cooling_purge)

Meter actual indirect-cooling purge transferred to a treatment operator, if present; preserve destination, composition, biocide use and treatment boundary. Direct environmental discharge requires separately speciated elementary rows.

• Selected flow: Indirect cooling-water purge to off-site treatment
• Flow property / unit: Volume / m3
• Amount rule: Measured attributable campaign exchange / accepted net powder kg; collect using cp_water
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_water
• Sources: jrc-cww-2016

Elementary flows

ammonia (ammonia_air)

Measure NH3 released beyond control equipment to outdoor air, unspecified subcompartment; report molecular NH3 mass, not ammonia-N. Assess moisture-related conversion; no positive default or historic reduction factor.

• Selected flow: ammonia 08a91e70-3ddc-11dd-a2a9-0050c2490048
• Flow property / unit: Mass / kg
• Amount rule: Measured attributable campaign exchange / accepted net powder kg; collect using cp_air
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_air
• Sources: alzchem-route, jrc-cww-2016

acetylene (acetylene_air)

Screen residual-carbide contact with moisture and measure any resulting C2H2 actually released to outdoor air, unspecified subcompartment. Occupational concentration is not a factory emission load.

• Selected flow: acetylene 4d9a8790-3ddd-11dd-911f-0050c2490048
• Flow property / unit: Mass / kg
• Amount rule: Measured attributable campaign exchange / accepted net powder kg; collect using cp_air
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_air
• Sources: icsc-cyanamide-2006, jrc-cww-2016

particles (PM2.5) (pm_fine_air)

Measure escaped particles with aerodynamic diameter at most 2.5 micrometres after controls, including documented fugitive sources, to outdoor air unspecified.

• Selected flow: particles (PM2.5) 08a91e70-3ddc-11dd-9293-0050c2490048
• Flow property / unit: Mass / kg
• Amount rule: Measured attributable campaign exchange / accepted net powder kg; collect using cp_air
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_air
• Sources: jrc-cww-2016

particles (PM2.5 - PM10) (pm_coarse_air)

Record only the nonoverlapping fraction above 2.5 and at most 10 micrometres, to outdoor air unspecified. If comparable cumulative PM10 and PM2.5 measurements are used, subtract PM2.5; never add this row to cumulative PM10.

• Selected flow: particles (PM2.5 - PM10) 08a91e70-3ddc-11dd-9501-0050c2490048
• Flow property / unit: Mass / kg
• Amount rule: Measured attributable campaign exchange / accepted net powder kg; collect using cp_air
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_air
• Sources: jrc-cww-2016

particles (> PM10) (pm_large_air)

Record escaped particles above 10 micrometres to outdoor air unspecified; derive by total minus PM10 only for comparable matched measurements. Missing size fractions remain unknown, not zero.

• Selected flow: particles (> PM10) fe0acd60-3ddc-11dd-a70a-0050c2490048
• Flow property / unit: Mass / kg
• Amount rule: Measured attributable campaign exchange / accepted net powder kg; collect using cp_air
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_air
• Sources: jrc-cww-2016

7. Allocation and Co-product Handling

rule_id	applies_to	rule	source_ids
allocation_physical	nitridation	Keep the physical mass, nitrogen and carbon balances before burden allocation. Reaction carbon retained in powder is part of its composition; internal dust return is not a co-product. Do not multiply physical outputs by allocation shares.	alzchem-route, jrc-cww-2016
allocation_subdivide	nitridation	Use stage meters and campaign-specific records to separate other production. No default co-product credit or allocation ratio is supplied. If an external co-product actually arises, document its identity, receiver, physical balance and reviewed allocation decision before modelling its burden.	jrc-cww-2016

8. Foreground Data Collection, Calculation, and Quality Rules

Data Collection Protocols

protocol_id	process_id	flow_role	record_type	raw_fields	collection_method	unit	frequency	temporal_coverage	site_scope	aggregation_rule	quality_evidence
cp_product	nitridation	finished_powder	weighing and assay	lot; gross; tare; net powder; moisture; total N; cyanamide-N; nitrate/ammonium/urea N; residual CaC2; lime; carbon; particle size; opening/closing stock; unique new acceptance/return/rework lot links; failed/zero-output lots; opening/closing WIP mass/composition and carried burdens	Calibrated net acceptance weighing and representative lot analyses; count each newly accepted physical lot once after rework/withdrawals. Independently reconcile acceptance against dispatch, returns and opening/closing finished stock; retain WIP mass/composition and associated burdens across periods without omission or duplicate counting.	kg	each lot	complete declared campaign	same powder line and grade	per 1 kg reference flow	calibration; sampling method; assay uncertainty; stock ledger
cp_material	nitridation	carbide_in; nitrogen_in	foreground measurements	input lot; grade; supplier; delivered and charged mass; stocks; gas state; assay	Calibrated scales and gas mass meters; reconcile charges, delivery and inventory. Record gas conversion and supplier conditions if volumetric.	kg	each lot or operating mode; continuous meters where available	same complete campaign as cp_product	all attributable stages within selected foreground	per 1 kg reference flow	weighing tickets; calibration; supplier assays; gas basis
cp_energy	nitridation	electricity_in	foreground measurements	meter start/end; stage; operating hours; grid voltage; geography; provider; shared loads	Read dedicated electricity meters; quantify justified shared loads and reconcile invoices. Preserve kWh and MJ conversion.	kWh	each lot or operating mode; continuous meters where available	same complete campaign as cp_product	all attributable stages within selected foreground	per 1 kg reference flow	meter calibration; load attribution; provider boundary
cp_water	nitridation	cooling_water_in; cooling_purge	foreground measurements	makeup; purge volume; density; T; circuit; receiver; composition; additives	Meter makeup and actual off-site purge separately; weigh or measure density for water mass. Reconcile circulation, evaporation and stock; identify all added chemicals.	kg; m3	each lot or operating mode; continuous meters where available	same complete campaign as cp_product	all attributable stages within selected foreground	per 1 kg reference flow	calibration; circuit diagram; treatment contract; analyses
cp_residue	nitridation	dust_out	foreground measurements	dust collection mass; internal return; external dispatch; composition; residual carbide; receiver	Weigh separately collected solid dust and retained stocks. Match external manifests and receiver acceptance; do not use total dust capture as atmospheric emissions.	kg	each lot or operating mode; continuous meters where available	same complete campaign as cp_product	all attributable stages within selected foreground	per 1 kg reference flow	scales; transfer notes; composition and acceptance
cp_air	nitridation	ammonia_air; acetylene_air; pm_fine_air; pm_coarse_air; pm_large_air	foreground measurements	source; species/CAS; control train; concentration; gas flow; T/P; wet/dry; test duration; operating mode; size fractions; detection limit	Use matched outlet concentration and gas-flow measurements after controls for each operating mode; characterize fugitives independently. Convert species and flow to common gas conditions; integrate loads over covered operating hours and preserve uncertainty. Integrate a measured volume flow rate over its matched interval; with already integrated gas volume, concentration times that compatible volume is the load and is never multiplied by operating hours again. Retain the raw period load before the single campaign normalization.	kg	each lot or operating mode; continuous meters where available	same complete campaign as cp_product	all attributable stages within selected foreground	per 1 kg reference flow	test report; method; calibration; gas conditions; size method; operating coverage

Calculation Rules

rule_id	Applies to	Formula or rule	Inputs	Output	source_ids
campaign_basis	all inventory rows	Define one complete same-site/product/grade/state/nitridation-route campaign pool. Retain raw period totals before burden assignment or division, including all attributable startup/shutdown, failed and zero-output batches, cleaning/losses, returns, rework and opening/closing WIP with carried burdens. Q is uniquely counted newly accepted net powder kg from cp_product; reconcile dispatch/stocks independently without a second stock correction. After numerator-unit conversion and justified burden assignment, divide each attributable total by the same positive Q once only; reference output is 1 kg. If Q = 0 preserve all raw totals and stock/fate records without per-kg results, invented output or excluded failed periods.	cp_product; cp_material; cp_energy; cp_water; cp_residue; cp_air	exchange per 1 kg reference flow
element_balance	nitridation	Reconcile whole measured wet streams and independent N/Ca/C/H/O and actual impurity inventories, including stocks/WIP and actual gas/liquid destinations, before allocation. CaC2 + N2 -> CaCN2 + C is an identity, not a yield/recipe, and generates no stoichiometric water; distinguish residual carbide, free carbon/lime and bound cyanamide carbon. For the screened residual-carbide/moisture pathway only where it actually occurs, CaC2 + 2 H2O -> C2H2 + Ca(OH)2 constrains species masses; independently evidence the actual reacted amount, water consumption and formed dry components. Keep measured moisture/free water and dry-component formation/consumption separate. Do not infer water, evaporation, conversion, product yield or missing species from COD or an unexplained closure residual.	cp_material; cp_product; cp_residue; cp_air	physical element balance before allocation	alzchem-route, jrc-lvic-s-2007, jrc-cww-2016, icsc-cyanamide-2006

Data Quality Requirements

requirement_id	Applies to	Requirement	Evidence
quality_basis	all inventory rows	Preserve measured basis, supplier product identity and background quantity compatibility independently. A valid flow UUID does not establish a complete provider dataset.	cp_material; cp_energy; cp_water
quality_unknown	all inventory rows	Unknown is not zero. Absence requires documented equipment/route and sampling evidence. Limits of detection are retained; no universal yield, moisture, density, composition or emission factor.	cp_air; cp_product
quality_period	nitridation	Cover startup, shutdown, normal operation and credible upsets in the campaign; explain unmeasured periods and their uncertainty.	cp_air; cp_energy; cp_product

9. Validation Rules

rule_id	applies_to	rule	source_ids
validate_reference	finished_powder	Require one powder output at 1 kg, complete qualifiers and resolved product-mass reference identity before usable guidance/dataset acceptance. A measurement pass does not resolve identity.
validate_balances	nitridation	Check physical mass/N/Ca/C and stock balances separately from allocated burdens; investigate residuals with uncertainty and detection limits. Internal transfers cancel at equal actual quantities.	jrc-cww-2016
validate_emissions	nitridation	Verify post-control outdoor loads, molecular NH3/C2H2 bases and nonoverlapping particle bins. Do not add captured waste dust, cumulative PM10, or upstream carbide emissions again. Direct water discharge requires its own verified species and medium.	jrc-cww-2016, icsc-cyanamide-2006
validate_completeness	all inventory rows	Reject complete-dataset claims with unverified reference/carbide/waste identity, unsupported conversion, unmeasured material pathway or unqualified provider. Independent scientific review remains required.

10. Published Dataset Profile

Field	Value
dataset_role	secondary_dataset; background_dataset
downstream_use	Compatible bulk ground calcium cyanamide fertilizer input, after identity and quality acceptance.
allowed_use	Declared site/period/assay and purchased-carbide route only.
excluded_use	Whole CPC leaf; granulated/enriched blends; pure substance or kg N substitution; use-stage claims; treating this unfinished draft as an accepted dataset.
required_metadata	Reference qualifiers; boundary; provider links; stocks; collection protocols; identity resolution; operating coverage.
required_quality_disclosure	Uncertainty; actual completeness; unresolved identities; conditional utility/waste identity; allocations and exclusions.
update_trigger	Route, assay, supplier, utility, dust treatment or monitoring change; identity clarification or new independent evidence.

11. Data Sources

Source id	Type	Reference	Used for
alzchem-route	literature	Alzchem, Product calcium cyanamide, Manufacture / Types / Quality; https://www.alzchem.com/en/brands/perlka/product-calcium-cyanamide/	Producer route and product-state distinctions; historic plant reduction, assay and temperatures are not universal defaults.
jrc-lvic-s-2007	official_guidance	European Commission, LVIC-S BREF, August 2007, 7.2.1.1, pp.356-357 (PDF401-402); https://bureau-industrial-transformation.jrc.ec.europa.eu/sites/default/files/2019-11/lvic-s_bref_0907.pdf	Upstream carbide manufacture and boundary distinction, and the residual-carbide/water reaction identity in §7.2.1.1; no historic energy/purity, actual hydrolysis extent or emission default.
jrc-cww-2016	official_guidance	European Commission, CWW BREF, 2016, BAT2 pp.543-544 (PDF573-574); https://publications.jrc.ec.europa.eu/repository/bitstream/JRC103096/jrc103096_cww_bref_10_2016.pdf	Horizontal chemical-sector stream inventory and monitoring, not fertilizer-specific factors.
icsc-cyanamide-2006	official_guidance	ILO/WHO, ICSC1639 Calcium cyanamide, Notes; https://inchem.org/documents/icsc/icsc/eics1639.htm	Residual carbide/moisture acetylene screening, no release fraction or LCI factor.
unsd-cpc3-2025	official_guidance	UNSD, CPC3 Explanatory Notes, 30Jun2025, p.165; https://unstats.un.org/unsd/classifications/Econ/Download/In%20Text/CPC_Ver_3.0_Exp_Notes_30Jun2025.pdf	34619 residual label and adjacent identities only; narrower membership still requires controller decision.