Particulate matter analyzer, collecting filter and system for analyzing and collecting samples from fluids

• US 7,254,212 B2
• Filed: 04/15/2004
• Issued: 08/07/2007
• Est. Priority Date: 04/16/2003
• Status: Active Grant

• Current Assignee: Horiba Limited
• Original Assignee: Horiba Limited
• Inventors: Kato, Junji, Saitoh, Katsumi, Fujiwara, Masahiko, Shinohara, Masayoshi
• Primary Examiner(s): Glick; Edward J.
• Assistant Examiner(s): KAO, CHIH CHENG G
• Application Number:
  US10/824,881
• Publication Number:
  US 20050041774A1
• Time in Patent Office: 1,209 Days
• Field of Search: 378/53, 378/45, 378/46, 378/49, 378/50, 378/83, 378/88, 378/89, 378/90, 378/47, 250/306, 250/307, 250/308, 250/309, 250/310
• US Class Current: 378/47
• CPC Class Codes: B01D 46/0002 Casings; Housings; Frame constructions
• CPC Class Codes: B01D 46/0006 Filter elements or cartridges installed in a drawer-like manner
• CPC Class Codes: B01D 46/10 Particle separators, e.g. dust precipitators, using filter plates, sheets or pads having plane surfaces
• CPC Class Codes: G01N 1/2202 involving separation of sample components during sampling
• CPC Class Codes: G01N 1/2205 with filters
• CPC Class Codes: G01N 15/0625 Optical scan of the deposits
• CPC Class Codes: Y10S 55/03 Vacuum cleaner

Abstract

A system, including a particulate matter analyzer and collecting filter, provides a method of analyzing and collecting samples from fluids, such as collecting particulate matter from air. A mass measuring unit and composition analyzing unit can be provided for either simultaneous or immediately consecutive measurements within a single instrument. The filter material can have an antistatic electricity characteristic and can be impregnated with reference material to enable calibration of the composition analyzing unit.

Claims

1. A particulate matter analyzer comprising:

a collecting unit for collecting particulate matter in a sample gas of only a predetermined size range on a filter;

a mass measuring unit for measuring mass of the particulate matter while on the filter; and

a composition analyzing unit for analyzing composition of the particulate matter while on the filter, wherein the measurement of mass and analysis of composition are performed on the same collected particulate matter on the filter within the particulate matter analyzer.

2. The particulate matter analyzer of claim 1, wherein the composition analyzing unit is configured to analyze the composition of the particulate matter by irradiating a measuring spot formed on the filter with radioactive rays or electron beams.

3. The particulate matter analyzer of claim 2, wherein the collecting unit is configured to enable the sample gas to pass through the filter, thereby forming the measuring spot on the filter, and the filter is made of a material which substantially does not emit fluorescent x-rays.

4. The particulate matter analyzer of claim 3, wherein the filter has an antistatic electricity characteristic.

5. The particulate matter analyzer of claim 4, wherein the filter includes a porous layer made of a fluororesin, and a gas-permeable reinforcing layer which is provided on a surface of the porous layer.

6. The particulate matter analyzer of claim 5, wherein the reinforcing layer is made of a non-woven fabric which consists of any one or a plurality of materials selected from polyethylene, polyethylenetelephtalate, nylon, polyester, and polyamide.

7. The particulate matter analyzer of claim 6, wherein the filter includes a predetermined reference material other than a target material to be collected to enable a calibration of a particulate matter analyzer processing the collected target material on the filter.

8. The particulate matter analyzer of claim 3, wherein the unit for collecting particulate matter includes a filter holding mechanism with a plurality of individual filter holder units, and wherein the holder units are progressively and automatically position individual filters at a sample taking station which permits the sample gas to pass through selected filters.

9. The particulate matter analyzer of claim 1, wherein the mass measuring unit is configured to measure the mass of the particulate matter by using one of a beta-ray absorption method, a pressure loss method, and a light scattering method.

10. A system for collecting particulate matter in a fluid and analyzing mass of the particulate matter and its composition, comprising:

a collecting unit including a source of filter members for performing a plurality of sequential measurements and a sample fluid supplying unit for directing a predetermined amount of a sample to a filter member to separate particulate matter of a predetermined size range from the sample fluid;

a mass measuring unit for measuring the mass of the particulate matter while on the filter member;

a composition analyzing unit for analyzing the composition of the particulate matter while on the filter member;

a transporting unit for moving one of the plurality of filter members from the sample fluid supplying unit to respectively the mass measuring unit and the composition analyzing unit; and

a controller unit for automatically enabling the collecting unit, mass measuring unit, composition analyzing unit, and transporting unit, wherein a plurality of measurements with a plurality of filter members are carried out on the particulate matter over a predetermined time period.

11. The system of claim 10, wherein the source of filter members includes an elongated roll of filter material and a feeding reel unit which positions a predetermined length of filter material to operatively engage the sample fluid supplying unit.

12. The system of claim 10, wherein the source of filter members includes a filter holding mechanism which rotates a plurality of individual filter members to operatively engage the sample fluid supplying unit.

13. The system of claim 10, wherein the filter members have an antistatic characteristic.

14. The system of claim 10, wherein the filter members include a predetermined reference material other than a target material to be collected to enable a calibration of the composition analyzing unit.

15. The system of claim 10, wherein the mass measuring unit and the composition analyzing unit are within the same housing and measure the particulate matter at a same location within the housing.

16. The system of claim 10, wherein the filter members include a non-woven fabric low in hygroscopicity.

17. The system of claim 16, wherein the non-woven fabric consists of one of polyethylene, polyethylenetelephtalate, nylon, polyester, and polyamide.

18. The system of claim 10, wherein the filter members include a porous layer of a glass fiber, a reinforcing layer, and a predetermined reference material other than a target material to be collected to enable a reference comparison when the collected particulate matter on one of the filter members is subjected to an analysis to determine quantity of the target material.

19. A particulate matter analyzer comprising:

a collecting unit for collecting particulate matter in a sample gas including a size separator unit for supplying a predetermined size and smaller of particulate matter, an elongated filter member having an upper and a lower transporting unit for moving a predetermined length of the filter member to receive the particulate matter from the size separator unit;

a mass measuring unit for measuring mass of the particulate matter as deposited on the filter member;

a composition analyzing unit for analyzing composition of the particulate matter as deposited on the filter member; and

a controller unit for automatically enabling the collecting unit, the mass measuring unit, the composition analyzing unit, and the transporting unit to perform a plurality of measurements on a series of predetermined lengths of the filter member automatically over a predetermined time period without an operator.

20. The particulate matter analyzer of claim 19 wherein measurement of the mass and analysis of the composition is performed on the deposited particulate matter on the filter member when a predetermined length of the filter member is held stationary at one location by the transporting unit.

21. The particulate matter analyzer of claim 19 wherein the filter member includes, within each predetermined length of the filter member, a calibration reference material to enable a calibration of the composition analyzing unit.

22. The particulate matter analyzer of claim 19 wherein the mass measuring unit and the composition analyzing unit are within a single housing and measure the particulate matter at the same location on the filter member within the housing.

23. The particulate matter analyzer of claim 19 wherein the filter member has an antistatic electricity characteristic.