System and method for landfill dewatering using a venturi air lift liquid pump

A system for collecting leachate from a solid waste landfill, comprising:

• a landfill gas well that extends from a ground surface and through a landfill waste layer to a leachate layer within the solid waste landfill;
• and
• an airlift venturi pump disposed within the landfill gas well and configured to collect leachate from the leachate layer, the airlift venturi pump comprising:
• an upstream entry pipe configured to deliver leachate from the landfill;
• an airlift section in fluid communication with the upstream entry pipe and configured to receive leachate from the upstream entry pipe, the airlift section comprising:
• an inlet pipe defining a first inside diameter,
• an outlet pipe defining a second inside diameter,
• a throat disposed between the inlet pipe and the outlet pipe, wherein the throat has a diameter that is narrower than the first inside diameter and the second inside diameter, and
• an air conveyance pipe comprising an outlet portion that is positioned at least partially within the first inside diameter and oriented in a direction other than orthogonal with respect to the inlet pipe, the air conveyance pipe configured to inject air into the airlift section;
• and
• a downstream exit pipe configured to deliver leachate away from the airlift section.

A method for collecting leachate from a solid waste landfill, comprising:

• passing the leachate through an airlift venturi pump, the airlift venturi pump comprising an upstream entry pipe configured to receive the leachate from the landfill, an airlift section in fluid communication with the upstream entry pipe, the airlift section having an inlet pipe, an outlet pipe, and a throat disposed between the inlet pipe and the outlet pipe, the throat having a diameter that is narrower than both the inlet pipe and the outlet pipe, and a downstream exit pipe in fluid communication with the airlift section and configured to transport the leachate away from the airlift section;
• and
• introducing, by an air conveyance pipe, an air stream into the inlet pipe, wherein the air conveyance pipe is at least partially inside the inlet pipe such that the air conveyance pipe and the upstream entry pipe have parallel axes;
• and
• facilitating a venturi effect in the throat to create a vacuum and pull the leachate therethrough.