Yun K.M.,Hiroshima University |
Yun K.M.,KAIST |
Suryamas A.B.,Hiroshima University |
Iskandar F.,Hiroshima University |
And 4 more authors.
Separation and Purification Technology | Year: 2010
Polymer nanofiber mats with various morphology structures (nanofiber, beaded-nanofiber, and composite particle/nanofiber) were prepared by electrospinning for application to aerosol particle filtration. The filtration performance of these polymer nanofiber mats was evaluated based on quality factors generated from measurement of penetration through the filter by sodium chloride (NaCl) aerosol particles ranging from 20 to 300 nm. These filtration test results showed that the quality factors of beaded-nanofiber filter mats were the best, even though the aerosol particle penetration of them was the highest of the morphology structures. The results of the present study show that morphology optimization of polymer nanofibers is an effective method for improvement of filtration performance, and it must be the future direction for development of new filtration media. © 2010 Elsevier B.V. All rights reserved.
Bao L.,Nippon Muki Co. |
Seki K.,Nippon Muki Co. |
Niinuma H.,AAF International B.V. |
Otani Y.,Kanazawa University |
And 4 more authors.
Separation and Purification Technology | Year: 2016
Slip flow phenomena are of great concern in aerosol filtration because of their ability to develop low-pressure drops and high collection efficiency air filters by using nanofibers. However, it is a difficult task to verify the slip flow effect on the reduction in pressure drop because the inhomogeneity in fiber packing also results in a decrease in pressure drop. In the present work, we propose pressure drop measurements at low pressures to verify the slip flow effect by distinguishing the effects of filter inhomogeneity. We found that the experimental dimensionless drag at low-pressure conditions, which was obtained with correction by the inhomogeneity factor measured at atmospheric pressure, followed the theoretical prediction that includes the slip flow correction (Kirsch and Stechkina, 1978) for both conventional PTFE and newly developed fluororesin nanofiber filter media. Because the dimensionless drags of both nanofiber filters decreased inversely proportional to the Knudsen number, we concluded that these nanofiber filters have low-pressure drops because of slip flow effects. © 2015 Elsevier B.V. All rights reserved.
Niinuma H.,Nippon Muki Co. |
Shibuya Y.,Nippon Muki Co. |
Bao L.,Nippon Muki Co.
Kobunshi | Year: 2013
We developed new fluororesin media with large pore size and thickness. It has high efficiency, low pressure-drop and long service-life which is similar to that of fiberglass media mainly used as HEPA filter media. The new HEPA filter with fluororesin media has lower pressure-drop than the fiberglass filter and a longer service-life than the conventional PTFE filter. Therefore it is possible to reduce the energy consumption at the operating stage of HEPA filters and we can provide an energy saving product that is reducing CO2 emission.
Nippon Muki Co. | Date: 2015-04-29
The air filter unit has a pleated filter medium with a zigzag shape in which a fibrous filter medium has been folded multiple times. The coefficients of linear expansion of the separators (space-supporting members) provided in each of the multiple folded spaces of the pleated filter medium are equal to or greater than the coefficient of linear expansion of the metal filter frame of the filter unit. Moreover, among said separators, the coefficient of linear expansion of each of separators that are provided at the side regions, which comprise the two side sections located at the outermost ends of the pleated filter medium in a second direction that is orthogonal to the direction of folding of the pleated filter medium (the first direction), is smaller than the coefficient of linear expansion of a separators provided in the central region that is flanked by the side regions.
Nippon Muki Co. | Date: 2014-02-05
[Problem] To provide an air filter for high temperature capable of maintaining the shape of a filter body and suppressing a pressure drop even when a filter medium area is increased to 50 to 65 m^(2)/m^(3) per unit filter capacity so as to respond to high air volume. [Means for Resolution] An air filter for high temperature which is formed by housing and fixing a zigzag shaped filter body including a filter medium made of a formed sheet of binder-free glass fiber and heat resistant mesh bodies sandwiching the filter medium from both side surfaces into a frame body with a heat resistant sealing material interposed between upper and lower edge portions of the filter body and the frame body for maintaining airtightness between the filter body and the frame body with a filter medium area of 50 to 65 m^(2)/m^(3) per a unit filter capacity, which includes a pair of comb-shaped holding plates sandwiching the filter body horizontally from airflow upstream/downstream sides at each upper/lower edge portion of the filter body and plural pairs of comb-shaped spacer plates sandwiching the filter body horizontally from airflow upstream/downstream sides between the upper and lower comb-shaped holding plates at intervals of 90 to 120 mm.
Nippon Muki Co. | Date: 2013-06-25
An air filter unit has a pleated filter medium with a zigzag shape in which a fibrous filter medium has been folded multiple times. The coefficients of linear expansion of the space-supporting members provided in each of the multiple folded spaces of the pleated filter medium are equal to or greater than the coefficient of linear expansion of the metal filter frame of the filter unit. The linear expansion coefficients of first space-supporting members are smaller than the linear expansion coefficient of a second space-supporting member. The first space-supporting members are provided in side portion regions including both side portions positioned at outermost sides of the pleated filter medium in a second direction perpendicular to the first direction. The second space-supporting member is provided in a central portion region sandwiched between the side portion regions.
Nippon Muki Co. | Date: 2010-06-23
An air filter comprising a filter pack comprising a folded nanofiber filter medium, fitted to a filter frame through a seal material, the nanofiber filter medium being a filter medium for an air filter, comprising a nanofiber filter medium which, when a filter medium face velocity is 5.3 cm/s, has a performance index of collecting target particle diameter of 0.3 m, 0.040 (1/Pa) or more, performance index of collecting target particle diameter of 0.1 m, 0.030 (1/Pa) or more, and performance index of collecting target particle diameter of 0.05 m, 0.050 (1/Pa) or more. By this, a high air volume and low pressure drop type high-performance air filter using a nanofiber filter medium can be provided.
Nippon Muki Co. | Date: 2014-07-16
To provide an air filter in which a filter pack is not moved in use as well as in which the filter pack does not fall off when used in horizontal direction. An air filter in which a sheet-shaped sealing material made of glass fibers is inserted into a zigzag-shaped end surface of a filter pack formed by folding a filter medium in zigzag shape and by inserting corrugated separators into folding spaces, and at least the zigzag-shaped end surface of the filter pack is surrounded by a filter frame having a C-shape in cross section and including folded portions formed by inwardly folding open ends, which includes a stopper between the folded portion in a downstream side and the filter pack and strip-shaped sealing materials made of glass fibers are embedded between the sheet-shaped sealing material and the filter pack so as to closely contact the separators in the folding spaces of the filter pack.
Nippon Muki Co. | Date: 2012-04-04
Provided is a double-pleated air filter where filter elements each of which ensures an inter-pleat gap (air passage) by folding filter media in multiple layers and by defining a pitch, a thickness and a folding shape of the filter media are arranged in the V-bank-shaped structure whereby the air filter can be used with a large air volume due to a low pressure drop. In the filter element which keeps an interval between filter media folded in a zigzag shape by an interval maintaining material, a relationship among an interval a (pitch) between a peak portion of a pleat and a peak portion of a pleat arranged adjacent to the pleat, a folded width b of the filter media, an interval c (a center portion gap) between the filter media at center portions of the pleats arranged adjacent to each other (an intermediate position of the folded width b of the filter media), an interval c (an opening portion gap) between the filter media in the vicinity of peak portions of the pleats arranged adjacent to each other, a thickness d of the filter media, and a width e (a distal end width) of the pleat in the vicinity of the peak portion of the pleat is set such that the relationship satisfies c/c1.1, c=a-e0.45mm, c=a/2-d and e/d2.
Nippon Muki Co. | Date: 2011-10-26
The invention provides a filter pack of which the mass is not increased, and moreover, the effective filter medium area is not reduced, and of which the pressure drop is sufficiently low, and the strength is sufficiently high, and an air filter using this. A pleated air filter pack is configured in such a way that dot embossed projections are provided on front and rear surfaces of a filter medium made of a non-woven fabric, the filter medium is folded in zigzag shape along creases of pleats, and the opposing embossed projections are brought into contact with each other when the filter medium is folded, thus maintaining the intervals between the filter media.