Providence develops infrared imaging to measure stack emissions
ABaton Rouge engineering firm has received a federal grant to develop technology to measure how effectively industrial flares burn unused hydrocarbons and other chemical waste.
Providence Photonics Inc., of Baton Rouge, is one of 24 companies nationwide to receive a Small Business Innovation Research Phase I Grant from the U.S. Environmental Protection Agency in 2013.
It is the first Louisiana firm to receive the grant from the EPA since 1987.
The $80,000 award will support Providence’s efforts to demonstrate the workability of its concept for gauging the chemical make-up of air emissions from stack flares at industrial sites.
The technology Providence is developing uses multispectral, infrared imaging to provide real-time measurements of concentrations of carbon dioxide, carbon monoxide and hydrocarbons in flare plumes.
Like exhaust from vehicles, unburned industrial emissions contribute to the formation of ozone — or smog — in the presence of sunlight.
The system Providence is working on would also make automated adjustments to more completely burn chemicals before they are released into the open air.
“This is for the proof-of-concept phase,” Yousheng Zeng, who leads the Providence team developing the new air-monitoring system, said of the EPA grant.
Plumes from flares are familiar sites in Baton Rouge and across the Gulf Coast, where stacks are used by refineries, petrochemical plants and other industrial facilities to combust waste gases, including unburned hydrocarbons.
Nationally, there are about 7,000 open-air flares in operation, according to the EPA.
While operators are subject to regulations on flare operations, there is no practical way to measure the precise rates of chemical emissions when they enter the open air from flares that rise 100 to 200 feet into the air.
At present, regulators and operators assume the flares have an efficiency rate of 98 percent if the flares meet regulatory requirements, but operators rely on estimates of air emissions, not actual measurements.
Numerous studies have found that the combustion efficiency of flares varies, even when operators meet regulatory guidelines, according to the EPA. Meanwhile, common procedures for adjusting emissions, like adding steam to the plume, can sometimes sharply reduce combustion efficiency even while achieving a cleaner-looking, whiter plume, Zeng explained.
The sensing system under development at Providence would give operators a way to know exactly what they are emitting and make ongoing adjustments to control flare efficiency.
“That is the key issue,” Zeng said.
A 2008 report by the Texas Commission on Environmental Quality underscores why understanding flare efficiency is critical. It found that 28 flares at 11 industrial sites in Harris County, Texas, created a combined 1,469.5 tons of volatile organic compound emissions in a year.
Zeng also noted that a flare operating at 96 percent efficiency would be emitting twice as much chemicals into the air as one operating at 98 percent efficiency.
“You want to burn (chemical waste) optimally,” he said.
The next steps for Providence include applying for an SBIR Phase II Grant from the EPA to help move its technology into the commercial marketplace. Providence is in the early stages of marketing another infrared imaging system for detecting industrial leaks. Zeng said he is optimistic the flare-monitoring system funded by the EPA can also move into the marketplace over the next couple of years.
“This could be used by any site that uses a flare,” he said.