--- title: Selective Catalytic Reduction url: "https://www.envanio.com/us-en/noise-control-and-air-filtration/products/product/selective-catalytic-reduction" date: 2026-09-24 modified: 2026-10-13 --- # Selective Catalytic Reduction ![](https://www.envanio.com/fileadmin/_processed_/f/c/csm_Envanio_Rendering_SCR_freigestellt_e03d82a5dd.webp "Selective Catalytic Reduction") ![](https://www.envanio.com/fileadmin/_processed_/7/b/csm_Envanio_Rendering_SCR-1_freigestellt_73e9482dcf.webp "Selective Catalytic Reduction") ![](https://www.envanio.com/fileadmin/_processed_/0/9/csm_Envanio_Rendering_SCR-2_freigestellt_b347958bf3.webp "Selective Catalytic Reduction") Emissions Control ![](https://www.envanio.com/_assets/15aee9713160ee0bd4ef9d7c531927c0/Icons/logo-universal.svg) Selective Catalytic Reduction ============================= Envanio Universal’s selective catalytic reduction (SCR) is an advanced emissions aftertreatment and acoustic silencing system engineered specifically for high-horsepower diesel engines, gas turbines, and industrial prime/standby power generation. Operating across wide exhaust temperature windows with precision closed-loop reagent dosing, our compact, modular systems ensure certified EPA Tier 4 Final and IMO Tier III compliance while delivering integrated sound attenuation, ultra-low ammonia slip, and minimal backpressure. The low-restriction catalyst and silencer flow geometry preserves rated engine horsepower and optimizes fuel efficiency. [ Request a Consultation ](https://www.envanio.com/us-en/contact-sales-envanio) ![](https://www.envanio.com/fileadmin/04_Icons/SVG/Envanio_ICONS_L%C3%B6sungen.svg "Modular & Standardized Construction")### Modular & Standardized Construction Scalable, pre-engineered module housings enable faster deployment for OEMs, custom equipment packagers, and retrofit applications while reducing installation complexity. ![](https://www.envanio.com/fileadmin/04_Icons/SVG/Envanio_ICONS_Space.svg "Multi-Stage Thermally Harmonized Housing")### Multi-Stage Thermally Harmonized Housing The system combines DPF soot capture, SCR catalysts, CO oxidation, and advanced silencer attenuation into a single compact and thermally optimized footprint. ![](https://www.envanio.com/fileadmin/04_Icons/SVG/Envanio_ICONS_Kompakt_und_Robust.svg "Mission-Critical Durability")### Mission-Critical Durability Designed for both emergency standby and continuous prime power applications, the system features heavy-duty, vibration-resistant construction to ensure maximum reliability and uptime. [ System Specifications ](#c891) [ How It Works ](#c893) [ Typical Applications ](#c892) [ FAQ ](#c894) [ Contact ](#c895) [ Request a Consultation ](https://www.envanio.com/us-en/contact-sales-envanio) ![](https://www.envanio.com/typo3temp/assets/_processed_/f/1/csm_stats-shape_e3a8ac716f.webp) Envanio Universal's SCR System Specifications ----------------------------------------------- | Process | Selective Catalytic Reduction (SCR) with Integrated Multi-Stage Aftertreatment & Silencing | |---|---| | **NOx Destruction Efficiency** | Up to 95 to 98% reduction across full engine operating load profiles | | **Operating Temperature Range** | 450°F to 1,050°F with active thermal management | | **Reagent Injection** | Diesel Exhaust Fluid (DEF) / 32.5% Aqueous Urea or Aqueous Ammonia | | **Target Pollutants** | Nitrogen Oxides (NOx), Particulate Matter (PM / Soot), Carbon Monoxide (CO), Hydrocarbons (HC), and VOCs | | **Dosing Skid Architecture** | 100% All-Electric injection (no plant compressed air required) | | **Ammonia Slip Control** | Integrated Ammonia Slip Catalyst (ASC) maintaining residual slip < 2–5 ppm | | **Construction Materials** | Heavy-duty aluminized steel, 304/316L stainless steel, and high-temp acoustic insulation | How Our SCR System Works -------------------------- 01 Exhaust Gas Intake Engine or turbine exhaust enters the inlet transition plenum, where CFD-optimized internal baffles ensure uniform gas velocity, temperature distribution, and acoustic wavefront dampening. 02 Diesel Particulate Filtration Exhaust passes through an integrated Diesel Oxidation Catalyst (DOC) and wall-flow Diesel Particulate Filter (DPF) to continuously oxidize CO/hydrocarbons and capture sub-micron soot particles. 03 All-Electric DEF Injection A precision all-electric dosing system injects finely atomized DEF/urea into the gas stream. Engineered static mixing sections ensure rapid vaporization and homogenous reductant distribution without crystallization. 04 Catalytic NOx Reduction The conditioned exhaust-reagent stream passes through base-metal or zeolite SCR catalyst honeycomb blocks, where NOx chemically converts into harmless atmospheric nitrogen (N) and water vapor (H₂O). 05 Ammonia Slip Mitigation A downstream guard Ammonia Slip Catalyst (ASC) oxidizes unreacted ammonia molecules, preventing secondary odor or atmospheric ammonia release. 06 Integrated Acoustic Silencing & Clean Discharge Treated exhaust traverses reactive and absorptive silencer baffles built directly into the housing, discharging through the exhaust stack at fully compliant acoustic and Tier 4 emission levels. 01/06 Typical Applications for SCR Systems -------------------------------------- Envanio Universal designs and manufactures systems for the purification of diesel and gas engine exhaust gases from nitrogen oxides (NOx) tailored to your specific requirements. Thanks to their mission-critical durability and advanced emissions aftertreatment, our selective catalytic reduction systems are well suited for the following applications. ###### Data Centers & Hyperscale Facilities Tier 4 certified emissions abatement and hospital-grade acoustic silencing for emergency standby diesel gensets ###### Hospitals & Healthcare Critical Infrastructure Zero-downtime backup power with ultra-low emissions and low noise profiles in sensitive municipal areas. ###### Marine & Naval Propulsion/Gensets IMO Tier III certified exhaust aftertreatment and spark-arresting silencing for workboats, commercial shipping, and yachts ###### Locomotive & Rail Prime Power Compact, low-profile engine exhaust aftertreatment built specifically for line-haul and switcher locomotives ###### Municipal & Remote Prime Power Continuous NOx and particulate control for remote industrial microgrids, water utilities, and gas turbine installations ###### Industrial Packaged Gensets & Compressors OEM and packager drop-in aftertreatment solutions for stationary reciprocating engine skids FAQ ----- ###### How does Envanio Universal's SCR prevent DEF deposit crystallization? By utilizing proprietary high-shear static mixing geometry, optimized evaporation lengths, and thermal insulation that maintains gas temperatures well above the urea decomposition point. ###### Is compressed air required for the urea injection system? No, Envanio Universal uses a 100% all-electric precision dosing skid, eliminating the need for external plant air compressors, air driers, and associated piping. ###### Can this SCR system integrate directly with engine exhaust silencers? Yes, our core engineering strength is acoustic and emissions harmonization. Our modular units combine catalytic reduction, particulate filtration, and reactive/absorptive silencing in one compact housing. Let's Talk ------------ Please contact us directly to schedule a personal consultation or submit your project details using our contact form to receive a complementary, no-obligation quote. ![](https://www.envanio.com/fileadmin/_processed_/7/1/csm_James_Mitchell_DSC00144_6c8aeb83fe.webp) James Mitchell Director Sales and Business Development [ +1-608-630-6338 ](tel:+1-608-630-6338) [ james.mitchell@envanio.com ](#) [ Get in Touch ](https://www.envanio.com/us-en/contact-envanio-universal) ![James Mitchell](https://www.envanio.com/fileadmin/_processed_/7/1/csm_James_Mitchell_DSC00144_6c0b0fdc50.webp "James Mitchell")