Landfill Leachate Collection Pipe Design...Landfill Leachate Collection Pipe Design Solid Waste...
Transcript of Landfill Leachate Collection Pipe Design...Landfill Leachate Collection Pipe Design Solid Waste...
Landfill LeachateCollection Pipe Design
Solid Waste Association of North AmericaNorth Carolina ChapterSpring ConferenceApril 25-28, 2016
Ali Khatami, Ph.D., P.E.SCS Engineers
Discussions
• Clogging at Leachate Collection Pipes• Traditional Design of Leachate Collection
Pipes• Innovative Design of Leachate Collection
Pipes• Construction Details
Clogging Issue
• Large quantities of leachate passing through a small area of geotextile potentially causes clogging
• Clogging reduces flow of leachate through geotextile
• Clogging of geotextile at leachate collection pipe potentially impedes free flow of leachate into the pipe
Rule of Transmissivities
Leachate must always flow from a transmissive medium into another medium with equal or greater transmissivity
Transmissivity Value Order
Waste < Sand < Geotextile < Geonet < Gravel < Pipe
Flow of water from left medium to right medium would be an ideal arrangement
Examples:Geotextile → Geotextile (√)Geotextile → Geonet (√)Geonet → Geotextile (X)Geotextile → Gravel (√)Geotextile → Sand (X)
Leachate Flow Path in Traditional Design
• from waste to sand layer (√)• from sand layer to upper geotextile of geocomposite (√)• from upper geotextile to geonet of geocomposite (√)• from geonet to upper geotextile of geocomposite (X)• from upper geotextile of geocomposite to geotextile
around gravel (√)• from geotextile to gravel (√)• from gravel to pipe (√)
Does Not Satisfy the “Rule of Transmissivities”
Leachate Flow Path in Innovative Design
• from waste to sand layer (√)• from sand layer to upper geotextile of
geocomposite (√)• from upper geotextile to geonet of
geocomposite (√)• from geonet to gravel (√)• from gravel to pipe (√)
Follows the “Rule of Transmissivities”