3-28-13 - Free

Mercury Measurement and Control Part 1 – Hot Topic Hour March 28, 2013

Sharon Sjostrom, P.E., Vice President Technology, ADA-ES LLC presented an overview of important considerations for achieving MATS compliance for mercury. Achieving consistent MATS compliance for mercury requires an integrated approach to plant operations. Fuel choices, boiler operations and technology choices for criteria pollutants and HAPS will affect mercury control and the ability to meet future regulations associated with ash and water.

Dr. James Staudt, PhD, President Andover Technology Partners, discussed the issues facing utility boilers, industrial boilers and Portland cement kilns that need to measure and control Hg emissions. Topics included:

A comparison of continuous mercury monitor measurement data for sorbent traps and analyzers, low level accuracy and bias between the two methods was explored.

Electronic CEMS	Sorbent Traps
Real-time measurement of Hg	Lower capital cost
Risk of lost data may be less	Simpler, but need people trained in handling samples and selecting correct trap size and sample rate.
EPA/ NIST protocol	In principle, accurate to lower concentrations
No need to send personnel up to collect/replace traps every few days.	More consistent with RATA method of choice.
Potential for process control

Methods to reduce the operating cost of mercury control systems and the benefit of variable control methods.

Activated Carbon usage can be reduced through use of a feedback control system with an electronic Hg CEMS

§ Savings depend upon facility particulars

o Coal Hg concentration and variability

o Boiler size

o Air pollution control system

o Operating characteristics

§ This concept also applies for other control methods besides ACl, although the economics will differ.

Mercury control issues facing Portland cement kilns.

Highly variable emissions
Very high removal efficiencies will likely require second baghouse

Bobby I.T. Chen, Client Program Manager, Integrated Emissions Solutions, at CB&I Shaw Environmental discussed “EMO™+HL, Total MATS Compliance Solution”. There are critical reasons to enhance mercury oxidization using CB&I’s technology because controlling mercury (Hg) emission from the coal combustion process is best achieved through a two-stage process. The first stage is to promote mercury oxidization at the combustion chamber outlet. The second stage is to provide absorbent to capture the oxidized mercury. On numerous of CB&I’s field EMO trials, EMO has been proven to achieve 90 plus percent Hg oxidization, thus facilitating the downstream AQCS Hg control efficiency. Furthermore, EMO was also found to be the most cost-effective way of controlling stack Hg.

Volker Schmid, PhD of Clean Air Engineering covered “Mercury Compliance Monitoring in 2015 and Beyond.” Monitoring mercury at the concentration levels specified by the new EGU MATS rules will be challenging for the cement and electrical utility industries, respectively. He made a case for using sorbent traps as the preferred alternative for mercury compliance monitoring for many of the facilities impacted by these requirements. Volker pointed to the accuracy of NIST calibrators which are an order of magnitude less accurate than what is needed in MATS. This is coupled with Hg CEMS inaccuracies which are also significant.

Capturing material over several days in a sorbent trap provides an accurate longer term measurement. It can be used with continuous mercury monitoring systems (CMMS) as a backup. The capital cost of sorbent traps is $100,000 to $150,000. This is less than half the capital cost of CMMS. Operating cost is $20,000-$30,000/yr and also about half that of CMMS.

Bios, Abstracts and Photos can be seen at: BIOS, ABSTRACTS, PHOTOS - 3-28-13.htm

The individual presentations are as follows:

Mercury Measurement and Control - Part 1, Webinar - Hot Topic Hour March 28, 2013