The Development of Wool-Based Passive Filters Toimprove Indoor Air Quality

Abstract:

It is well known that wool carpets and upholstery permanently remove many gaseous pollutants from the air, thus improving indoor air quality, and peoples’ wellbeing. The aim of the work reported here was to develop wool-based filters that could be used in homes and offices to improve indoor air quality. The abilities of wool, jute, and some other materials used in building interiors, to absorb common indoor air pollutants, formaldehyde, sulphur dioxide and nitrogen oxides were compared. Testing was conducted in a chamber that reproduced the conditions found in a typical room. Wool and jute were found to give high levels of absorption and the results were used to design six types of wool-based filters that were intended to be compact, with high rates and capacities of absorption. The filters were passive, relying on high surface areas and diffusion, rather than forced air circulation, thus minimising their net environmental impact. Filters based on wool yarn, roving, balls and unbacked carpet, were all very effective, absorbing between 94 and 96% of the air pollutants over six hours. This study has shown that wool-based passive filters can significantly improve indoor air quality, and represent a new use for wool.

• Periodical: Key Engineering Materials (Volume 671)
• Pages: 219-224
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.671.219
• Online since: November 2015
• Authors: Steve J. McNeil*, Larissa I. Zaitseva
• Keywords: Built Environment, Filters, Formaldehyde, Indoor Air Quality, Sulphur Dioxide, Wool

References

[1] B.O. Brooks, W.F. Davis, Understanding Indoor Air Quality, CRC, Boca Raton, USA, (1992).

[2] P.E. Ingham, S.M. Causer, R.C. McMillan, The role of wool carpets in controlling indoor air pollution, Proc. Text. Inst. Conf. Blackpool, UK, (1994).

[3] S. McNeil, Removal of Indoor Air Contaminants by Wool Carpet, AgResearch Technical Bulletin, AgResearch, Christchurch, New Zealand, (2014).

[4] M. Walsh, A. Black, A. Morgan, G.H. Crawshaw, Sorption of SO2 by typical indoor surfaces, Atmos. Environ. 11 (1977) 1107-1111.

DOI: 10.1016/0004-6981(77)90242-6

[5] P. Ingham, Fire Safety of Wool Carpets, WRONZ Technical Bulletin, Wool Research Organisation of New Zealand, Christchurch, New Zealand, (1999).

[6] S. McNeil, Acoustic Advantages of Wool Carpeting, AgResearch Technical Bulletin, AgResearch, Christchurch, New Zealand, (2014).

[7] P. Martini, M.J. Spearpoint, P.E. Ingham, Low-cost wool-based fire blocking inter-liners for upholstered furniture, Fire Safety J. 45 (2010) 238-248.

DOI: 10.1016/j.firesaf.2010.03.005

[8] R.A. McCall, S.J. McNeil, Comparison of the energy, time and water usage required for maintaining carpets and hard floors, Indoor Built Environ. 16 (2007) 482-486.

DOI: 10.1177/1420326x07082781

[9] W. Meade, Consumer Properties of Carpets, WRONZ Technical Bulletin, Wool Research Organisation of New Zealand, Christchurch, New Zealand, (1998).

[10] S.J. McNeil, M.R. Sunderland, L.I. Zaitseva, Closed-loop wool carpet recycling, Resour. Conserv. Recy. 51 (2007) 220-224.

DOI: 10.1016/j.resconrec.2006.09.006

[11] W.H. Rees, Heat insulation properties of carpets, Carpet Rev. 23 (1969) 39-51.

[12] P.E. Ingham, M.R. Sunderland, S.J. McNeil, R. Marazzi, Lanasan NCF: Nanoparticles enhance carpet performance, Int. Dyer, 191 (2006) 23-25.

[13] S.J. McNeil, L.S. Tapp, The design and initial evaluation of visual cues in carpets to assist walking, J. Text. Inst. ahead-of-print (2015).

[14] K. Corscadden, J. Biggs, D. Stiles, Sheep's wool insulation, Res. Cons. Recy. 86 (2014) 9-15.

[15] N.A.G. Johnson, E.J. Wood, P.E. Ingham, S.J. McNeil, I.D. McFarlane, Wool as a technical fibre, J. Text. Inst, 94 (2003) 26-41.

[16] U.R. Amrit, Bedding textiles and their influence on sleep. AUTEX Res. J. 8 (2007) 252-254.

[17] C. Garrow, L.J. Stephens, M.R. Ewing, Evaluation of surgical masks: The potential of resin-treated wool, Surgery, 69 (1971) 881-883.

[18] S.J. McNeil, Heavy metal removal using wool filters, Asian Text. J. 10 (2001) 88-90.

[19] J.A. Schutz, W. Humphries, A Study of wool/polypropylene nonwovens as an alternative to the Hansen filter, Text. Res. J. 80 (2010) 1265-1277.

[20] S.J. Leighs, S.J. McNeil, W.J. Meade, Wool filtration media opportunities and applications. Visions for Fibres and Textiles Conference, Melbourne, Australia, (2012).

[21] T. Kinney, Wool: Master's Design Thesis, University of Texas, Austin, USA, (2014).

[22] R.H.T. Barker, M.E. Taylor, P. Johnstone, C. van Koten Biodegradation of Wool Carpet Pile, AgResearch Technical Bulletin, AgResearch, Christchurch, New Zealand, (2013).

[23] P. Gibbs, The land recycling option for wool carpet. Carpet Recycling UK Conference, 2009, UK.

[24] V.V. Kadam, L.R. Meena, S. Singh, D.B. Shakyawar, S.M.K. Naqvi, Utilization of coarse wool in agriculture for soil moisture conservation. Indian J. Small Ruminants, 20 (2014) 83-86.

[25] R.S. Górecki, M.T. Górecki, Utilization of waste wool as substrate amendment in pot cultivation of tomato, sweet pepper, and eggplant. Pol. J. Environ. Stud. 19 (2010) 1083=1087.

[26] V.D. Zheljazkov, Wool-waste as organic nutrient source. Waste Management, 29 (2009) 2160-2164.

DOI: 10.1016/j.wasman.2009.03.009

[27] Information on www. campaignforwool. org/2014/10/14/biodegradable-wool-test-complete.