Abstract: In a data acquisition system and method for real time monitoring of stack gases in a continuous monitoring system, data is collected from sensors and prepared for output to a regulatory agency. The data collected may relate to emissions of oxides of nitrogen, carbon monoxide, and oxides of sulfur, typically from an industrial facility. Sensors in the exhaust gas pathway report data to a programmable logic control device and are then stored in a data storage area. A data acquisition module quantifies the stored emissions data. The quantified emissions data is then sent to a regulatory agency via a communications link.

Abstract: In a data acquisition system and method for real time monitoring of stack gases in a continuous monitoring system, data is collected from sensors and prepared for output to a regulatory agency. The data collected may relate to emissions of oxides of nitrogen, carbon monoxide, and oxides of sulfur, typically from an industrial facility. Sensors in the exhaust gas pathway report data to a programmable logic control device and are then stored in a data storage area. A data acquisition module quantifies the stored emissions data. The quantified emissions data is then sent to a regulatory agency via a communications link.

Abstract: A method for determining total landfill gas production capability and pollutant emission rates involves measuring gas pressure in a soil cover at various locations around the landfill. These measurements are preferably made successively and repeated. The tester determines an average gas pressure and its spatial uncertainty envelope and measures soil pneumatic permeabilities by taking soil samples, preferably at various locations. The soil is tested to determine viscous and inertial resistance coefficients to characterize permeability. The gas composition is determined preferably at each pressure measuring location, and the coefficients, gas pressure and composition measurements are used to calculate total gas emission.

Abstract: A pump comprising an elongated housing adapted to be positioned in a landfill gas well. The housing has a peripheral wall, an interior chamber and apertures in the peripheral wall leading from the exterior of the housing to the chamber so that liquid can flow from the well into the chamber. A pressure responsive valve member is mounted in the chamber on the peripheral wall and extends across the apertures. A discharge conduit extends from the chamber to a location above the housing. When the liquid level in the chamber rises to a predetermined upper level, gas under pressure is supplied to the chamber. The gas under pressure causes the pressure responsive valve member to close the apertures and it forces the liquid out of the chamber through the discharge conduit.

Abstract: A method for projecting the landfill gas collection rate of a surface collector, including removing some of the cover material from the landfill to expose a test area of the refuse in the landfill and measuring the venting rate of the landfill gas through the test area under essentially steady state pressure conditions in the landfill. Additional cover material is then removed to enlarge the test area and the measuring step is repeated. The measured venting rates are used for projecting the approximate collection rate for a surface collector.

Abstract: In a landfill gas recovery system, the breakthrough danger is minimized, and the system efficiency is improved, by providing pressure-equalizing low-impedance gas paths such as aggregate-filled symmetry trenches positioned within the landfill and surrounding, at least partially, the primary collection zone. The symmetry trenches may be connected to the system's low-pressure source to serve as secondary collectors. A sensing trench positioned within the landfill along the periphery of the collector's zone of influence can be used to monitor the collector pressure and to automatically maintain it at a safe level. The sensing trench can also serve as a secondary equalizing path in heterogeneous landfills. Hot spots may advantageously be tapped by auxiliary collectors whose pressure level bears a predetermined proportional relationship to the primary collector pressure.

Abstract: A method of measuring the flow of landfill gas from a surface of a landfill comprising placing a receiver having an opening therein on the landfill surface so that the landfill gas can flow through the opening and enter the receiver, conducting the landfill gas from the receiver through a conduit, measuring the flow of the gas in the conduit, and discharging the landfill gas from the conduit to the atmosphere through a dynamic pressure attenuator.

Abstract: A method of collecting landfill gas from a landfill comprising providing a porous collector in the landfill having a relatively broad collection zone in the path of migrating landfill gas, controlling the pressure in the collector to induce the landfill gas near the collector to flow into the collector, removing the landfill gas from the collector, and substantially excluding air from the atmosphere from entering the collector when the collector is collecting landfill gas.

Abstract: A dynamic pressure attenuator comprising a housing and a plurality of tubes extending through the interior of the housing and defining wind passages. Each of the tubes has a plurality of radially extending ports. The housing has an inlet to admit a gas to the interior of the housing. When wind passes through the wind passages, the static pressure in the ports is substantially normal ambient static pressure and the dynamic pressure in the ports is essentially zero. Gas from the inlet passes through the ports and the wind passages to the atmosphere.