The automatic control of determination of ammonia-nitrogen with the principle of Nessler s reagent colorimetry is described , moreover, distillation pretreatment device and pipeline control machinery with wriggle pump is designed.

Therefore,a drying strategy,including pre-steaming before kiln drying and final conditioning after kiln drying,was developed by the authors with the intent to improve lumber drying quality.

Corrosion Cause analysis of pre-distillator in urea plant and countermeasures;