The Dichotomous Partisol-Plus Sequential Air Sampler is a multi-filter sequential sampler (up to 16 filter sets) for the simultaneous collection of the fine (PM-2.5) and coarse particles contained in PM-10

The Dichotomous Partisol-Plus Sequential Air Sampler is a multi-filter sequential sampler (up to 16 filter sets) for the simultaneous collection of the fine (PM-2.5) and coarse particles contained in PM-10. An alternate configuration called the 50/50 split flow configuration splits a PM-2.5 flow into two equal parts for simultaneous collection on two filters.

Product Details

Applications
The dichotomous configuration permits the differentiated mass determination and chemical composition of the fine and coarse particles contained in PM-10. This can be very important for source identification.

The 50/50 split flow configuration allows for the collection of PM-2.5 on two different types of filter material simultaneously. This permits the material collected at a location to be evaluated by a greater number of analytical techniques.

Technology
These dual-flow configurations incorporate a filter exchange mechanism that shuttles two filters simultaneously. This is based upon the proven mechanism used in the basic configuration of the Partisol-Plus Sampler. These systems include a second flow controller to maintain a second flow at the constant volumetric flow rate required for sampling.

Details

Both the dichotomous and 50/50 split flow configurations of the Partisol-Plus Sequential Air Sampler contain two flow controllers to maintain high-quality flow control. The two sample streams are controlled by two independent flow controllers that function according to R&Ps ActiVol flow control system to maintain constant volumetric flow rates.

The systems contain two supply magazines and two storage magazines for filter cassettes. Each filter exchange involves the movement of two filter cassettes simultaneously from the supply magazines to the sampling location, and from the sampling location to the storage magazines. The photo below shows the inner chamber of a dual-flow Partisol-Plus Sequential Air Sampler with the additional magazines.

Dichotomous Configuration
The dichotomous configuration of the Partisol-Plus Sequential Air Sampler splits a PM-10 sample stream into a 15 l/min flow containing fine (PM-2.5) particles and a 1.67 l/min flow with coarse particles. These filters can be evaluated separately in the laboratory for fine and coarse particles.

The photo above shows the dichotomous virtual impactor that divides the total 16.7 l/min PM-10 flow into its fine and coarse fractions. The schematic below depicts the flow paths in the system.

50/50 PM-2.5 Split Flow Configuration

Different post-collection analytical methods require the use of different filter materials. Rupprecht & Patashnick developed the 250/50 split flow configuration to facilitate the collection the collection of PM-2.5 onto two different filter material types simultaneously. The total 16.7 l/min PM-2.5 sample flow is divided equally into two 8.35 l/min sample streams that pass through two 47 mm diameter filters simultaneously. The collection filters may be made of different materials to accommodate the varying requirements imposed by different analytical methods.

The flow splitter for 50/50 sampling is shown below installed in a Partisol-Plus Sampler.

The schematic below details the flow pattern through the two collection filters of the 50/50 split flow configuration.

Filter Analyses and Support Services
For commercial and network users of the Partisol Air Sampler, IML Air Science provides quality-assured filter weighing and analysis services using NIST-traceable analytical equipment. In addition to offering pre- and post-collection gravimetric analyses of Partisol filters, IML can also identify chemical constituents including carbon, metals, sulfates, and nitrates.