Optical based opacity and flow monitoring system and method of monitoring opacity and flow
US6050656A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 23, 1997 |
| Grant date | Apr 18, 2000 |
| Priority date | — |
| Expiry date | Oct 23, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/534
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A pollutant emissions monitoring system and a method of measuring pollutant emissions, particularly fly ash, of gas passing through stacks of coal-fired boilers. An all optical-based emission monitor has an opacity monitor and a flow rate monitor connected to a remote data processing facility by a single fiber optic cable. A timing/calibration wheel assembly initiates measurement cycles and calibrates the opacity monitor. A first beamsplitter polarizes a collimated light beam from a light source into two collimated light beams, an upstream and a downstream beam. A second beamsplitter receives the collimated light beams, reflects a portion of the light beams to the flow rate monitor and passes the remainder of the light beams to a retro-reflector. The remote data processing facility determines the flow rate of the fly ash by measuring a plurality of pairs of upstream and downstream flow signals transmitted from the flow rate monitor, correlating each of the plurality of pairs of flow signals, normalizing the correlated flow signals and summing the normalized flow signals. The retro-reflector returns the remainder of the light beams to the opacity monitor. The remote data processing …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.