Reducing Harmful Exhaust Emissions

Dresser-Rand is a pioneer in lean burn technology to reduce NOx.

Standard and custom-designed retrofit kits are available.

Depending on engine model and exhaust emissions goal, conversions could involve:

Using precombustion chambers (PCCs) to ignite lean engine mixture

Features	Benefits
Highest energy ignition source	Provides the necessary energy to consistently ignite the lean mixtures required for low NOx emissions Supports consistent firing via multiple simultaneous ignition sites along the torch path Reduces main chamber ignition delay while promoting complete combustion Supports combustion stability over engine’s entire operating range
Consistent ignition	Reduces misfire, detonation and cycle-to-cycle firing pressure variation
Enhanced performance at varying speeds and loads	Provides the ignition energy necessary to reduce NOx while keeping carbon monoxide (CO), non-methane hydrocarbons (NMHC) and fuel consumption at acceptable levels for best overall engine performance
Allows engines to meet or exceed today’s emission requirements	Adapts to changing needs when applied with other Dresser-Rand lean burn combustion system hardware upgrades
Proven OEM technology	Assures component compatibility for unmatched efficiency and reliability

Increasing engine air flow for leaner combustion

By increasing engine air flow, the peak combustion temperature is lowered and NOx is reduced. Air flow can be increased by:

Reducing load on piston scavenged two stroke units and/or increasing speed (depends on model or serial number)
Converting non-turbocharged units to turbocharged style engines (for example, converting HBA to HBA-T or KVGR to KVSR)
Modifying or upgrading existing turbochargers (simply changing the turbo nozzle ring results in minor increases)
Replacing original turbochargers with modern high performance turbochargers specifically chosen using OEM engine design parameters

Installing new or upgraded engine combustion air coolers

As air flow increases, the need increases for cooling combustion air before it enters the power cylinders. Engine air cooler upgrades include:

Internal scavenging air coolers (TLA 2 stroke engine models)
On or off-engine scavenging air coolers
Scavenging air cooler or plenum adapters
Scavenging air header
On and off-engine turbocharger air aftercoolers (4 stroke engine models)
Rework of existing air intake manifold
Replacement or "exchange" air intake manifolds
Modification or replacement of existing auxiliary water pump

Dresser-Rand's Fuel Management Systems

Engines converted to lean burn design require attention to fuel injection. Optimum fuel admission measures differ from engine to engine, but may include:

Using directional fuel injection (DFI)
Modifying fuel cams and using DFI
Upgrading to Dresser-Rand's Fuel Management System for four-cycle gas engines

Directional fuel injection:

Provides high velocity gas injection that improves mixing
Provides the initial stratification within the main chamber to support adequate mixing in the precombustion chamber
Is used with modified cam timing to support lean burn conversion for some Dresser-Rand engines

Incorporating improved engine control features

Depending on the engine type, controls are updated to meet lean burn operational requirements.
Incorporate required/desired features in existing control systems or with add-on control panel and associated control devices.

Evaluating compatibility of existing auxiliary systems

Engine modifications may affect suitability of the following existing auxiliary systems and accessories:

Unit utility cooler
Cooling system piping and temperature control devices
Air intake filter and piping system
Exhaust silencer and associated piping system
Control system, including on-engine components
Operating procedures

Additional Information

Visit the Reciprocating Products section of our web site.

Contact Information

Dresser-Rand
Reciprocating Operations
100 Chemung Street
Painted Post, NY 14870 USA
Tel: (Int'l +1) 607-937-2011
Fax: (Int'l +1) 607-937-2905