Landfill Gas Treatment and Flares at Cherry Island Landfill

 

Landfill Gas Treatment and Flares at Cherry Island Landfill

 

Landfill Gas Treatment and Flares at Cherry Island Landfill

 

Landfill Gas Treatment and Flares at Cherry Island Landfill

 

Landfill Gas Treatment and Flares at Cherry Island Landfill

 

Landfill Gas Treatment and Flares at Cherry Island Landfill

 

Landfill Gas Treatment and Flares at Cherry Island Landfill

 

Landfill Gas Treatment and Flares at Cherry Island Landfill

 

Landfill Gas Treatment and Flares at Cherry Island Landfill

 

Landfill Gas Treatment and Flares at Cherry Island Landfill

 

Landfill Gas Treatment and Flares at Cherry Island Landfill

 

Landfill Gas Treatment and Flares at Cherry Island Landfill

 

Contract: $3,448,000

Design-Build Team Members
Owner: Delaware Solid Waste Authority

Engineer: Pennoni Associates Inc.

Operator: Enpower Corporation

Contractor: Johnston Construction Company

Key Accomplishments:

• Scheduling - The project required intensive project management and scheduling to coordinate the installation of driven pile foundations and rigging of large equipment within a very limited area adjacent to the main landfill access road. This was all accomplished while fast-tracking the construction to allow DSWA to be able to provide Conectiv Power Generation with low sulfur and hydrogen sulfide landfill gas as soon as possible.
• Coordination - The project work area was extremely congested and deliveries of the treatment plant scrubbers and flares required tight coordination between landfill operations, construction personnel, and vendors to avoid interruptions to the landfill.
  
• Flare Rigging – Installation of the John Zink, LLC LO-NOX® flares, which are among the larges such flares currently in operation, required extensive coordination to rig into place without damaging the ceramic insulated flare stack, burner and igniter. A 250 T primary crane and a 60 T tailing crane were used to unload and set the flares.

Johnston Construction Company, as general contractor, provided construction and commissioning services under a public-bid, design-bid-build, fixed price contract for the $3.4 million installation of a landfill gas treatment system and flare; filter/chemical feed building including a reverse osmosis water purification system, vacuum belt filter press, and chemical feed skid; landfill gas piping including underground 24-inch HDPE landfill gas main with associated tie-ins to the existing system and large diameter stainless steel gas duct above grade; a bypass road to provide access to existing landfill storage areas during treatment plant during construction; several pile foundations for the treatment equipment and flares; and site utilities, HVAC systems, controls, and electrical facilities. All work was required to be performed with minimal disruption to the existing landfill gas collection system and landfill operations.

The landfill gas treatment and flare system consist of a 9,000 scfm, 2-stage Mobile Bed Absorber, Gas Technologies Products, LLC LO-CAT® hydrogen sulfide treatment plant; two John Zink, LLC 4,500 scfm, ultra low emission, LO-NOX® flares; and associated chemical feed and filtration equipment. The landfill gas treatment equipment and flares were procured directly by the Delaware Solid Waste Authority.

The LO-NOX® flares which tower over 50 feet into the air are among the largest such flares installed in the United States. Johnston Construction Company has installed a similar flare at the Modern Landfill in York County, Pennsylvania.

The LO-CAT® landfill gas treatment plant will treat 9,000 scfm of landfill gas with a maximum of 2,000 ppmv of hydrogen sulfide. The plant includes a sulfur removal capacity of 1 ton per day and hydrogen sulfide removal efficiency up to 99%. After treatment, the landfill gas is sent to Conectiv Power Delivery, where it is converted into electricity. This is only the second landfill gas system of this size in the United States. The other was also installed by Johnston Construction in Warren County, New Jersey.

The project was fast-tracked to maximize the Delaware Solid Waste Authority’s return on investment. It was completed in time for the planned operational start-up in July 2007.