Wood emissions test standards

Figure 4. Formaldehyde emission test results (mg/1) using the desiccator method according to JIS A 1460 2001 standard [9], F designation formaldehyde emission <0.3 mg/f corresponding to the emission of natural wood.

Another furnace that does not require fuel preparation is the stoker boiler, which was used by New York State Electric Gas Corporation (NYSEG) in its TDE tests. At NYSEG, the stoker boiler, which has a 1649°C (3000°E) flame temperature (as does the cyclone boiler), has routinely blended low quaUty coal, and more recently, wood chips with its standard coal to reduce fuel costs and improve combustion efficiency. In the tire-chip tests, NYSEG burned approximately 1100 t of tire chips (smaller than 5x5 cm) mixed with coal and monitored the emissions. The company determined that the emissions were similar to those from burning coal alone. In a second test-bum of 1900 t of TDE, magnetic separation equipment removed metal from the resulting ash, so that it could be recycled as a winter traction agent for roadways. 

Wood-fired power boilers are generally found at the mills where wood products are manufactured. They are fired with waste materials from the process, such as "hogged wood," sander dust, sawdust, bark, or process trim. Little information is available on gaseous emissions from wood-fired boilers, but extensive tests of particulate matter emissions are reported (19). These emissions range from 0.057 to 1.626 gm per dry standard cubic meter, with an average of 0.343 reported for 135 tests. Collection devices for particulate matter from wood-fired boilers are shown in Table 30-21. 

Standard practice for the determination of VOCs (excluding formaldehyde) emissions from wood-based panels using small environmental chambers under defined test conditions... 

The typical power range for wood chip boilers is between 25 and 120 kW and for pellet boiler up to 40 kW. Wood chip fired room heating boilers reach an overall efficiency of up to 91% (under test conditions, practical efficiency 70-85%), pellet boilers even up to 93% under test conditions (practical efficiency 88-91%). Emission standards can easily be met by most of the systems in base and part load. 

Grot, D. "Plan for Testing Model for Formaldehyde Emissions from Pressed Wood Products" National Bureau of Standards,... 

The incidence of perceptible formaldehyde in homes, offices and schools has caused widespread uncertainty about the safety of living with formaldehyde. This uncertainty was enhanced by the large scale installation of urea formaldehyde foam insulation (UFFI) because a substantial part of this material was made from small scale resin batches prepared under questionable quality control conditions, and was installed by unskilled operators (10). The only reliable way to avoid such uncertainty is to know the emission rate of products and develop a design standard that allows prediction of indoor air levels. The first and most important step in this direction was achieved with the development and implementation of material emission standards. As indicated above, Japan led the field in 1974 with the introduction of the 24-hr desiccator test (6), FESYP followed with the formulation of the perforator test, the gas analysis method, and later with the introduction of air chambers (5). In the U.S. the FTM-1 (32) production test and the FTM-2 air chamber test (33) have made possible the implementation of a HUD standard for mobile homes (8) that is already implemented in some 90% of the UF wood production (35), regardless of product use. 

Within the scope of the project several new adhesive formulations were developed and tested. The formulations were based on DME (dimethoxyethanal) resin and the products derived from it to produce formaldehyde-free wood adhesives. The investigated adhesives were evaluated on laboratory scale in order to study their technical performances, their gluing parameters, their reactivity as well as their formaldehyde emissions. It was found that all formulations met the requirements of current standards EN 319 1993-08 and that for class P2 particleboards for general uses. From the technical point of view, major advantages of the tested systems were found to be colourless, low toxicity, easy handling, and high stability at room temperature (long shelf-life, pot-life and open-time). The formaldehyde emissions of the boards produced were found to be comparable with those of solid untreated wood (F JIS A 1460 2001 standard). 

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