Uprate Combustion System to DLN1+ (FG2L)

The MS6001B DLN product has two designs: DLN1 for 9, 15, or

25 ppm corrected NOx; and DLN1+ for 5 ppm corrected NOx.

Note that the DLN1+ design is compatible with existing DLN1

end-covers. Currently, DLN1+ is not available for dual fuel units

(gas only). DLN1+ is available for all MS6001B units firing at 2020°F

and above. It includes new liners, new transition pieces, and

new secondary nozzles. For DLN1+, no changes to the turbine

repair/replace procedures are expected. Figure 65b illustrates the

evolution of emissions reduction offered by GE since year 1990.

The building block approach to lower-emissions uprates offered by

GE is illustrated in Figure 65c. The DLN1+ uprates provide the

quickest solution to comply with stringent emissions regulations

because it leverages proven experience and provides a platform for

future NOx and CO reductions by allowing a building block approach.

DLN1+ offers many improvements over DLN1. (See Figures 65d

and 65e.) Among these are:

• Various combinations of hardware and software building blocks

allow flexible emissions offerings, depending on the customer’s

current needs and future requirements. Examples include:

– The standard 5/25 ppm NOx/CO guarantee with fuel ambient

range of 0°F-120°F requires DLN1+ combustion hardware,

DLN1+ controls with corrected-parameter control, and

closed-loop emissions feedback. This full DLN1+ technology

package also offers a 4/25 ppm NOx/CO guarantee with

ambient range of 10°F to 20°F

– The DLN1+ combustion-hardware-only package offers a

7/25 ppm NOx/CO guarantee or 9/9 ppm NOx/CO guarantee

over respective temperature ranges.

GE Energy | GER-4217B (06/2010) 31

Figure 64. Original MS6001B DLN fuel gas system

SRV GCVGCV-1

To Purge System

P

S

T

GTV

GSV

SRV Speed/Ratio Valve

GCV Gas Control

GSV Gas Splitter

P Primary

S Secondary

GTV Gas Transfer

Dry Low NOx Gas Fuel System

GSV

Figure 65a. Current MS6001B DLN fuel gas system

6B DLN1 Gas Fuel System – Independent Control Valves – Current Design Standard

SRV Speed/Ratio Valve

GCV-1 Gas Control Valve (Primary)

GCV-2 Gas Control Valve (Secondary)

P Primary

S Secondary

SRV

GCV-1

Purge Air

P

SGCV-2

Figure 65b. Evolution of emissions reduction

NO

x (to

ns) /

MW

-yea

r

Technology Enablers• 3D reacting flow• Advanced coatings• Active fuel staging

’08’95’90 ’00

DLN1+ Emissions Reduction Evolution

DLN1+

DLN1

15ppmWater injected

42ppm

< 5ppmDLN1 fleet experience

150k hours running below 5ppm, and 50k below 3ppm NOx

future140+9E

16390+7B-EA

180+

DLN 1

3 6B

DLN 1+Frame DLN1 DLN1+Frame

Figure 65c. DLN1+ building blocks

Lower Emissions

6B DLN1+hardware

CPCCPC

CLEC

++Tuning valves

+

DLN1 15ppm < 5ppm NOx

6B DLN1+ Building Blocks

Demonstrated 5ppm NOx and 8ppm CO performance

• The combustion inspection interval is extended from 8,000

FFH / 50 FFS to 16,000 FFH / 450 FFS. DLN1+ includes wear-

resistant Extendor materials and coatings to extend maintenance

intervals.

• Proven and patented sealing technology for tighter performance

and longer intervals; also used on GE F-Class fleet.

• Equivalent or similar turndown to DLN1 (i.e., 60% or better with

inlet bleed heat).

System advancements that resulted in the current 5 ppm DLN1+

are illustrated in Figure 66a. Critical to the operation of the DLN1+

system are the following:

• Enhanced fuel-air mixing

• Independent pilot gas

• Can level primary fuel tuning valves

• Closed Loop Emissions Control

• Dilution staging enhancement

Lean Head End (LHE) Reduced NOx Combustion Liners (FR1B)

The liner offered in this option is specially designed to reduce

NOx emissions about 10% compared to standard combustion liner.

Gas-only and dual fuel (distillate only) versions are available and

are intended for short-term use only. Note that dual fuel versions

require an atomizing air system.

Benefit:

A benefit of LHE liners is lower NOx, the value of which depends

on the frame size and fuel (gas-only or dual). For simple-cycle dry

operation, a 15% reduction of NOx can be realized.

LHE liners on all machines have a new mixing hole pattern that

reduces NOx. All of these high technology liners have with TBC

coating applied to improve life. (See uprate FR1G for more on TBC

application on liners.) The crossfire tube collars have hard-facing

32

Figure 65d. GE’s DLN1+ system improvements

Closed Loop Emissions Control(CLEC)

Can level primary fueltuning valves†

Staged dilution

Class C TBC

Enhanced fuel-air mixing

Redesigned secondaryfuel nozzle with

independent pilot†

Enhancedventuri

Continuous DynamicsMonitoring (CDM)

New fuel gas skid

Accessories:

DLN1

DLN1+

Liner dilution holes

†Not required for 5ppm NOx

DLN1+ System Advancements

Figure 65e. GE’s DLN1+ combustion improvements

6B DLN1+ Combustion Hardware

• For DLN1 to DLN1+ upgrade liner, transition piece, and secondary (center) nozzle need to be changed

• Hardware designed for 24,000 fired hours and 450 starts

• No impact on turbine durability

• Designed for 6B cycles firing temperatures, 2020 to 2100°F

• Includes all 6B DLN1 CLEX Extendor product features

• Staged dilution moved from liner to TP

• Liner aft end with F-class liner cooling

• TP thermal barrier coating upgraded w/clothseals

Figure 66a. Significant improvements included in DLN1+

DLN1+ Next Generation <5 ppm NOx

Fuel-Air Mixing Enhancement Dilution Staging Enhancement

NOx

Independentpilot gas

Extendor wearsurfaces

Cloth seals

DilutionEnhancement

Closed Loop EmissionsControl (CLEC)

Can Level Primary FuelTuning Valves

EnhancedFuel-AirMixing

Class C TBC

Integratedaft mount