Penetration of Diesel Exhaust Particles (DEPs) through Fibrous Filters Produced Using Melt-Blown Technology

Abstract

It is well known that diesel fumes are carcinogenic to humans and may cause inflammation of the respiratory tract, cardiovascular problems, etc. Diesel exhaust particles (DEPs) occurring in diesel fumes are fractal-like aggregates with diameters ranging between 10 and 2000 nm, with various compounds adsorbed on their surface. The fractal-like structure of DEPs and their nanosize leads to the problem of theoretically predicting the DEPs' filtration efficiency. Thus, experimental studies on effective protection against DEPs as well as theoretical modeling are essential. This study analyzes both experimentally and theoretically the mechanical and electret filters and their potential effectiveness in the filtration of DEPs. The theoretical analysis of the filtration process on fibrous fabrics was performed using classic filtration theory, assuming that the filtration layer can be treated as a system of a single fiber located in the Kuwabara cell. The experimental results show that the fibrous filters, produced using melt-blown technology, provide a high level of protection against DEP aerosols (93 %-99 %). The obtained filtration efficiencies are (in some cases) even higher than requested for particulate respiratory half-mask type 2 (made from a fibrous filter). However, the theoretical results obtained using classic filtration theory indicate lower filtration efficiencies than the experimental ones.

Reducing particulate emissions by using advanced engine oil nanoadditives based on molybdenum disulfide and carbon nanotubes

“…7 d) using Eqs. ( 2 ), ( 3 ), ( 4 ) and ( 5 ), assuming that the volume shape factor of the particles is equal to 24 . The primary particles measured using FAPES had a spherical shape, and fractal-like particles were formed only after deposition on the surface.…”

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“…7d) using Eqs. 2-5, assuming that the volume shape factor of the particles is equal to [23]. The primary particles measured using FAPES had a spherical shape, and fractal-like particles were formed only after deposition on the surface.…”

All-polymer hybrid electret fibers for high-efficiency and low-resistance filter media

“…To protect the public from being infected via droplets and aerosols [3], protective respirators are highly demanded. Currently, respirators are mostly composed of micro-sized melt-blown fibers with large pore size (10-20 μm), rendering a low pressure drop thereby satisfying breathing comfort [4]. However, determined by the single filtration mechanism of size sieving, melt-blown filters suffer from low filtration efficiency towards aerosols with small particle size, which is especially poisonous [5].…”