Selective Catalytic Reduction (SCR) Unit Services

How does selective catalytic reduction work? Selective catalytic reduction (SCR) uses ammonia injected at higher temperatures to react with oxides of nitrogen in the air. The nitrogen oxides and ammonia are converted to harmless nitrogen and water. This process can reduce diesel engine emissions.

Maintenance on SCR units can be challenging due to red-hot material buried deep in ash, intense temperatures and noxious fumes. Typically, plants require a cooling-off period necessitating a long pause in production before personnel can complete the repair.

However, our technicians perform the needed maintenance, sometimes with the boiler still running, allowing you to bring the SCR unit back online in record time. We routinely work in temperatures exceeding 400 degrees, kept cool in our proprietary PPE cooling & life support system. This reduces or eliminates lost production costs and expensive downtime for oil refineries, chemical facilities and power plants.

SCR units are designed to remove about 90 percent of nitrogen oxides, but SCR catalyst maintenance and management is essential for ensuring that they operate at full capacity. This includes monitoring the catalyst’s activity level and watching for heavy ash buildup that can cause a severe drop in pressure. In addition, excess SCR ammonia can create ammonia slip, which causes numerous problems.

A selective catalytic reduction unit is the first line of defense in preventing emissions of nitrogen oxides. As a precursor of ozone, nitrogen oxides are emitted by boiler and internal combustion engines which are subject to EPA regulations.

SCR uses ammonia or urea (generally converted to ammonia) injected at higher temperatures to react with oxides of nitrogen in the air. The nitrogen oxides and ammonia are converted to harmless nitrogen and water. Used since 1957, this process reduces emissions from diesel engines, ships and power plants.

We’ll complete any scope of work needed to ensure your SCR unit runs at peak capacity, consistently and reliably.