{
  "title": "污水脱氮外加碳源投加量与比价计算模型",
  "updated": "2026-11-10",
  "disclaimer": "所有指标为典型参考值，以批次《产品合格证 / COA》为准；执行标准与版本以合同技术协议及现行有效版本为准。 K 值必须经现场小试与运行数据校正。",
  "formulas": {
    "theoretical_cod_kg_per_d": "Q(m3/d) × ΔTN(mg/L) × K × 10^-3",
    "product_kg_per_d": "theoretical_cod_kg_per_d ÷ cod_equivalent(kg COD/kg 产品)",
    "liquid_volume_m3_per_d": "product_kg_per_d ÷ (density(t/m3) × 1000)",
    "daily_cost_yuan": "product_kg_per_d ÷ 1000 × unit_price(yuan/ton)",
    "yuan_per_kg_COD": "unit_price ÷ (cod_equivalent × 1000)",
    "yuan_per_kg_N": "daily_cost ÷ (Q × ΔTN ÷ 1000)"
  },
  "variables": {
    "Q": "日处理水量 m³/d",
    "delta_TN": "硝态氮去除量 mg/L（进出水总氮差）",
    "K": "安全系数（现场修正）",
    "cod_equivalent": "产品 COD 当量 kg COD/kg 产品",
    "density": "液体密度 t/m³（20℃）",
    "unit_price": "到厂吨价 元/吨（含运费口径需一致）"
  },
  "K_guidance": {
    "theoretical": 2.86,
    "theoretical_note": "反硝化化学计量：去除 1 g NO3⁻-N 理论消耗 2.86 g COD（以乙酸钠计）",
    "field_sodium_acetate": "3.5–5（新系统调试、低温、水质波动大时先取 4–5）",
    "field_composite": "4–5",
    "field_glucose": "4–6"
  },
  "workeds_example": {
    "input": {
      "Q_m3d": 5000,
      "delta_TN_mgl": 10,
      "K": 4,
      "product_id": "naac-l20"
    },
    "steps": {
      "theoretical_cod_kg_per_d": 143.0,
      "product_kg_per_d_at_K_equals_1": 917,
      "product_kg_per_d_at_K_equals_4": 1280
    },
    "note": "完整修正还需考虑进水原有碳源、内回流携带 DO、实际反硝化速率与温度。"
  },
  "transport_conversion": "20–30% 液体乙酸钠 1 吨 ≈ 0.88–0.91 m³（按 20℃ 密度区间折算）"
}