Process Ammonia Analyzer

The ZS8100-NH3 measures 0–50 ppm NH₃ as standard and is configurable to 500 ppm, with an accuracy of ±0.5 ppm or ±2% of reading and a <2 s T90 response. It uses tunable diode laser absorption spectroscopy (TDLAS), which locks onto an NH₃ absorption line for low-ppm ammonia-slip measurement at SCR/SNCR catalyst outlets. This line-locked approach is the alternative to broad-band gas fitting where NH₃ would be inferred from multiple overlapping gas channels.

The measurement requires a stable optical path, purge air for high-dust ducts, a heated extractive path when a retrofit loop is used, and an application-matrix review for wet-stack duty. H₂O, CO₂ and SO₂ spectral background is handled through line selection and matrix review rather than a blanket rejection claim. Known matrix limits: high-dust ducts require a purge design, wet-stack or cold extractive runs require heated sample handling, and NH₃ ranges above 500 ppm require a configuration review.

The default sampling mode is in-situ, built around a cross-duct optical path, a purge air system, an optional heated extractive retrofit path, and an internal NH₃ reference cell. High-dust environments are supported with purge air once the purge design is confirmed per duct loading. Excluded configurations are an unheated extractive line for low-ppm NH₃ slip duty, cold extractive lines where NH₃ adsorption cannot be controlled, and an unreviewed wet-stack matrix at the SCR/SNCR outlet. Compatible conditioning systems are referenced as the ZS-SCS-400 and ZS-SCS-600.

Zero/span validation uses auto-validation with the internal NH₃ reference cell; the interval is site-specific. Routine maintenance covers inspecting the purge-air path, checking optical alignment, verifying the heated extractive path when fitted, and running the NH₃ reference-cell validation, with purge-air filtration elements as the only consumable where fitted. The calibration approach supports SCR/SNCR ammonia-slip monitoring and stack-emission reporting where project documentation requires it.

CE is approved as a product badge, and ATEX is approved with the final zone scope confirmed per project. A CEMS / stack-reporting package is listed as Conditional — it covers the application-listed duty, with the method and reporting scope confirmed per project rather than asserted as a blanket certification. For SCR/SNCR architecture, low-ppm NH₃ slip is measured on the catalyst-outlet path with TDLAS line selection, purge protection and optional heated extractive handling, so the analyzer signal can feed dosing review without relying on delayed manual sampling.