PULP AND PAPER INDUSTRY
Direct Measurement of Air Emissions from Area Sources at Pulp and Paper Site Including Large Aerated and Non-Aerated Treatment Lagoons
The area sources found at pulp and paper mills typically include solid waste landfills, storage lagoons, clarifier tanks, and liquid waste treatment lagoons.
The site assessment of area sources found at paper and pulp industry sites are very similar to other industries, including the chemical manufacturing industry and the petroleum refining industry. These sites have large liquid waste treatment unit process that usually have low-level emissions of compounds emitted from other sources on site. This means that the compounds that are the focus of the air emissions from the liquid treatment processes are also found in the upwind ambient air.
As such, the USEPA flux chamber technology is ideal for these area source assessment since the flux chamber isolates the emitting surface from the ambient air thus avoiding any affect from an upwind source. Compounds of concern from a pulp/paper mill may include halomethane (related to bleaching only), methanol, reduced sulfur compounds, and odor.
Accessing locations on large treatment lagoons or ponds is often a challenge given that most large treatment lagoons have earthen berms and limited access (photo 1). Suspending the USEPA flux chamber from overhead structure is always preferred since this approach affords complete control of the chamber placement with minimum disturbance of the liquid or sludge surface, the shore, and the bottom of the lagoon. A boom crane is the vehicle of choice for many assessments (photo 2).
Performing assessments of lagoons or treatment ponds with surface aerators (photo 3, 4) or mixers (photo 5) also presents challenges. The key here is to map out unique surface areas related to the mixer or aerator, and collect flux data and surface area information about each unique area. These data are then summed to provide the flux from the area of the process mechanically disturbed. Very often, liquid samples are collected from the unit process, and the flux data along with the liquid source data are used to develop a site-specific emissions model. Tom Card provides these services, along with field testing support including expert liquid sample dipping expertise (photo 6).
Studies of large lagoons or ponds have been conducted to demonstrate that the USEPA flux chamber technology is the most cost-effective assessment approach for these industrial wastewater treatment facilities.
Photo 1- Flux Chamber Testing on Pulp Mill Treatment Lagoon
Photo 2- Boom Crane Used to Suspend Flux Chamber for Emission Assessment
Photo 3- Flux Chamber Used to Measure Emission from Surface Aerator
Photo 4- Measuring Flux of Gas Species in Three Zones of Aeration and Mixing Around Surface Aerator
Photo 5- Flux Measurement of Emissions from Mixer
Photo 6- Collecting Lagoon Liquid Sample Co-Located with Flux Measurement