The ClosureTurf Pressure Relief Valve is a required component of the ClosureTurf system to prevent gas from accumulating under the geomembrane. The Relief Valve is not a gas collection component, but rather a protective measure for the final cover. It is designed to protect the membrane component from gas buildup (ballooning) during malfunction of the primary gas collection system by venting gas to the atmosphere. However, it can also be an integral part of the overall ClosureTurf Surficial Gas Collection System.
Surficial Gas Collection System
The SGCS is cutting edge technology that outperforms conventional gas collection systems on every metric. In many cases, you can eliminate or at least reduce the need for deep gas wells.
How The SGCS Works:
The system relies upon positive internal landfill pressures to push the gas to the surface below the membrane. The membrane is an impermeable shield that prevents gas (fugitive emissions) from escaping into the atmosphere.
The SGCS strips create a designed capacity pathway across the gas field for the gas to travel to the collection points (surficial collection wellheads).
Negative pressures are introduced in at the wellhead into collection base through and beneath the membrane where the gas is trapped for collection. As the gas moves through the SGCS wellhead and into the collection header the gas can be monitored as required by regulations.
The Pressure Relief Valve is placed in the gas field away from the surficial collection strips and is designed to remain sealed during active gas collection and release in the event the primary system malfunctions to prevent (ballooning) gas buildup beneath the membrane.
The Automatic Isolation Valve is placed either in the SGCS wellhead or header system. The valve`s primary function is to prevent gas backflow from adjacent non-ClosureTurf areas during malfunction periods of the primary gas collection system.
- Reduced capital costs
- Quicker installation (no drilling)
- Reduced condensate management and treatment
- Higher collection efficiency
- Landfill oxidation potential eliminated
- Higher compliance standards (surface scans)
The surficial collection strips are included in a SGCS design for the purpose of creating gas collection conveyance channels below the membrane.
The amount of and placement of the strips is based upon design parameters associated with a sites specific gas modeling for gas generation rates.
The Isolation is also a safety valve. The valve is designed to perform as a one way check valve to prevent a backflow of gas into the ClosureTurf system through the header pipe from adjacent non-ClosureTurf areas during malfunction periods of the primary gas collection system. The isolation valve can be placed at the collection wellhead or header system.
Pressure Relief Valve (PRV)
The patented PRV is a safety valve that is designed to work with the ClosureTurf system. The PRV is designed to protect the membrane component from gas buildup (ballooning) duringa malfunction of the primary gas collection system by venting gas to the atmosphere. The valve is a dual purpose valve in that it opens to allow gas (pressure) to escape when needed and seals (under vacuum) to prevent air intrusion into the collection system. The PRV was designed to meet the CT systems requirements for an extremely low pressure release/seal with a high flow capacity.
Surficial Collection Base
The Surficial Gas Collection Base is designed to be the point of interface between the membrane, underlying collection strips, auto isolation valve and a collection wellhead.
The base provides high gas flow capacity, low profile and a stabile base for the isolation valves and wellhead components.