New Developments in Mercury Measurement and Control unveiled in Hot Topic Hour on April 11, 2013
The Hot Topic Hour yesterday proved that the technologies for mercury monitoring and control are in a state of development and change. New sorbent developments promise lower operating costs. New monitoring methods offer better process control. Multi-pollutant reduction systems could offer a cost effective solution for Franken–MACT.
Sanjeev Jolly, Vice-President of Engineering at Eco Power Solutions, presented data on an all-in-one system that addresses several pollutants simultaneously – NOx, SOx, HCl, HF, particulate, and heavy metals including mercury and CO2. The system provides very high removal efficiencies for all the pollutants except mercury. Tests have shown very little residual SO2 and particulate. The lowest efficiency was on mercury at 89 percent. The pilot plant is being revised with better mist eliminators. It is believed that this will increase the mercury reduction to 95 percent. The pilot plant uses sorbent traps rather than mercury CEMS, so particulate mercury or mercury in mist droplets is going to be captured. McIlvaine essentially asked why go to the trouble to change mist eliminators. Just use a Mercury CEMS and you can claim the higher efficiency even with the less efficient mist eliminator.
In the Mercury Webinar Part 1, the speakers addressed the fact that there is a difference between measurement with sorbent traps and mercury CEMS. This was attributed to the particulate mercury which is counted in the sorbent trap method but not the CEMS, which just measures mercury in the gas phase. Here are the questions which should be addressed:
How significant is the amount of particulate mercury compared to gaseous? EPA decided to ignore particulate mercury on the basis that the amount was inconsequential.
Does particulate mercury create health problems? One speaker in the earlier Mercury Webinar said that particulate mercury would fall out and be absorbed in the ground surrounding the plant.
Why worry if the law only regulates gaseous mercury?
Why try to use logic when there is a regulatory precedent for placing opacity monitors before the scrubber because it was the only place to accurately make the measurement, regardless of the fact that the scrubber is a big factor in particulate emissions?
Are some of the issues with NIST standards and protocol gases just as big a variable?
Marc Sylvester, Vice-president for Sales at Midwest Energy Emissions Corp (ME2C), said that their mercury capture programs are in use at several utilities even though they have only been actively marketing the product for 18 months. They have proven very cost effective compared to traditional ACI. Midwest utilizes several patented technologies to control emissions from utility and industrial boilers. The results of the last three field demonstrations of their Sorbent Enhancement Additive technology achieved greater than 90 percent capture at less than one half the cost of Brominated Activated Carbon with less than half the amount of material needed.
Dan Kietzer, Business Development Manager at SICK Process Automation, discussed the advancements in the design and performance of mercury CEMs over the past few years and how a new technology will benefit the end user from a cost and performance standpoint. Dan listed the following:
Advantages of Zeeman – AAS
- Continuous measuring method
- No moving parts
→ No mechanical wear
→ Long-term stability
(Maintenance cycle of light source: ≥ 1 year)
- Automatic drift correction for
§ Light source modifications
§ Contamination of optical surfaces
- Identical influence of cross sensitivity components on measuring and reference signal
→ Best possible cross sensitivity correction
The fast response time means it can be used as a process analyzer. A number of units are already installed in the U.S. Annual maintenance is only around $ 6,000/yr.
Bios, Abstracts and Photos can be seen at: BIOS, ABSTRACTS, PHOTOS - 4-11-13.htm
The individual presentations are as follows: