aquakin.direct_n2o_emission#

aquakin.direct_n2o_emission(plant, solution, params=None, *, n2o_species='SN2O', kla_ratio=1.0)[source]#

Direct N₂O stripped from the activated-sludge reactors (kg N₂O-N/d).

The activated-sludge model must track a dissolved nitrous-oxide state (n2o_species, default "SN2O" – present in the N₂O kinetic models, e.g. asm3_2step_n2o). N₂O is stripped at the aeration mass-transfer rate, so only the aerated reactors emit; this reconstructs each reactor’s oxygen kLa (the same control-aware reconstruction evaluate_bsm2 uses) and its dissolved N₂O trajectory, and time-averages the stripping flux (aquakin.plant.ghg.stripped_n2o()).

If the model has no n2o_species state (the standard ASM1 BSM2 plant, which does not resolve N₂O), the direct N₂O emission is 0 – the model has no nitrous oxide to strip. Use an N₂O-capable activated-sludge model to get a non-zero direct footprint.

Parameters:

  • plant (Plant) – A plant whose activated-sludge reactors carry n2o_species.

  • solution (PlantSolution) – A solved trajectory over the evaluation window.

  • params (jnp.ndarray, optional) – Plant parameters used for the run (defaults to the plant defaults).

  • n2o_species (str) – Dissolved N₂O-N state name (default "SN2O").

  • kla_ratio (float) – N₂O-to-O₂ mass-transfer-coefficient ratio (default 1.0).

Returns:

Time-averaged stripped N₂O-N mass flow (kg N/d).

Return type:

float