Complex Unintended Consequences Obscure the Path Forward for Air Pollution Control

A small Ohio town no longer exists thanks to the unintended consequences of air pollution control. A nearby power plant spent hundreds of millions of dollars to reduce NO_x.  The catalyst not only reduced the NO_x it converted SO₂ to sulfuric acid.  Within a few days, the acid deposition did such great damage to the buildings in the town that the utility agreed to buy the complete town and pay for relocations.  In the ensuing decade, catalyst suppliers have redesigned their product to eliminate this problem.

New mercury regulations have such low emission limits that the instrument just to measure gaseous mercury can cost hundreds of thousands of dollars. Prior to issuing the regulation, EPA tested a number of stacks and found that all the mercury existed in gaseous form.  Therefore, the regulations only required measurement of gaseous mercury.  In response to the regulation requirements, power plants, cement plants and waste-to-energy plants embraced a two-step solution.

Step one was to convert the gaseous mercury to particulate mercury.  Step two was to remove the particulate mercury.  The end result is that if step one is very efficient and step two is not, there is lots of particulate mercury being emitted.  Another unintended consequence is that particulate mercury will not travel far, whereas gaseous mercury can transverse the globe.  Even though this problem has been evident for a few years, there is still no proposed change in the regulations.

The recent regulation of many pollutants combined with new technology which makes it possible to remove all the pollutants in one device has greatly increased the use of fabric filters. However, there has not been a recognition of what McIlvaine describes as “The importance of FIFO vs. LIFO in Dust Cake creation.”

Direct sorbent injection (DSI) and embedded catalyst dictate a new approach to bag cleaning.  In addition to discrete particle capture, bag filters are being tasked with:

• Mercury removal
• Acid gas absorption
• Dioxin destruction or capture
• NO_x reduction

The importance of the method of bag cleaning can be illustrated by use of the accounting approach to inventory. Two options are first in first out (FIFO) and last in first out (LIFO).  If the price paid stays the same, the choice between the two accounting methods makes no difference.  But, if the cost of recent inventory is greatly different than the past, then the accounting method makes a big impact on profits.

The capture of discrete particles is the equivalent of price parity.  Let’s say that when you pulse a bag you are always discharging the latest particles to arrive and the remaining cake consists of the earliest. Since the ability of a matrix of dust particles to act as a filtration medium does not change, it does not matter which particles remain.  In fact, maintaining a somewhat permanent layer of cake protects the fabric from wear.  Also a more permanent cake provides higher dust capture.  It has been shown that on-line cleaning results in some re-deposit of dust particles.  But this is does not impact discrete particle capture efficiency.

The new paradigm with DSI is a big price difference. The newly arrived lime particle has the capability to absorb acid gases. The lime particle deposited earlier is already converted to calcium sulfate and provides no additional absorption capability. The semi-permanent cake layer is very undesirable for acid gas capture. Mercury re-emission is also a risk for an activated carbon cake which is semi-permanent. So it is very important to adopt FIFO and not LIFO.

This leads to the obvious question as to which are the best cleaning methods to achieve LIFO?  The long running debate about surface filtration vs. depth filtration needs to be reviewed in light of FIFO.  Also, the pulsing method itself needs to be reviewed.  Do some methods result in more re-entrainment of particles in the previous cake than do others?  Should more of the cake be removed with each pulsing?

It could be argued that the reaction takes place in the ductwork and not on the bag.  But the big difference in performance of bag filters vs. precipitators with DSI proves that the cake absorption is substantial.

There may be lots of research on this subject but if so, McIlvaine would appreciate feedback on it.  If there is not, it is an area deserving lots of attention.

Bag cleaning is also made more challenging by the increasing use of ceramic filter elements. The advantage of these elements is the ability to remove dust at 850°F.  The older generation rigid ceramic has been replaced by ceramic fiber media which can be pulsed.  However, this media cannot necessarily be pulsed with the identical system used for synthetic bags. An alumina refinery in Australia was having cleaning problems with a ceramic filter. Pentair Goyen analyzed the situation and provided a more robust pulsing system. This solved the problem.

Ceramic, glass and even synthetic media are incorporating catalyst in the media to reduce NO_x or oxidize dioxins. Do these designs require a different cleaning approach?  The catalyst in the Clear Edge design is not on the surface.  So, the dust cake will not affect performance except if it causes maldistribution of the gas.  If more gas flows through one area than another, the reactivity of the system is reduced.

A broader subject is the whole approach to cleaning. High pressure/low volume is the most popular option. Does capture of these other pollutants open the door for high volume /medium pressure or even for reverse air cleaning? 

The potential for the one-stop shopping is great.  Costs of pollution control can be reduced for new installations.  The small footprint makes a big difference in the cost of upgrading existing plants to meet new air pollution rules.  It is, therefore, important to understand and then maximize FIFO potential.  McIlvaine will be interviewing experts in the various niches to shed more light on this.  The results will be published in:

1ABC Fabric Filter

3ABC FGD and DeNOx Knowledge Systems

44I Power Plant Air Quality Decisions (Power Plant Decisions Orchard)

Industrial Air Plants and Projects

For information on how to participate contact: Bob McIlvaine at 847-784-0012 ext. 112 rmcilvaine@mcilvainecompany.com.

Air and Water Monitoring Market to grow to $28 Billion Next Year

In 2017 sales of water monitoring equipment and services will be $17 billion and air monitoring services will be $11 billion.  This is the latest forecast in N031 Air and Water Monitoring: World Market.

Asia will be the leading region followed by the Americas. Chinese sales will be over $4 billion representing one-third of the entire Asian market.

Thermo Fisher has been in the Chinese air pollution monitoring business for decades. By one definition it is said to have a 70 percent market share of ambient air monitors used in Chinese cities.  It sold its first mercury monitor in China more than ten years ago.  The Thermo decision to locate its air pollution research center in China is testimony to confidence in its ability to protect intellectual property in the country.

The monitoring business is a small part of the total Thermo business but has contributed to the 10 percent annual increase in revenue over the last five years.   The EPS CAGR is an impressive 17 percent. Revenue growth has been 28 percent per year in China with sales of $1.4 billion last year.

The ambient market is growing fastest in developing countries where governments are investing in networks.  However, in the U.S. there is a significant market for ambient networks purchased by power plants and industrial facilities which have to address new federal standards as well as embryonic standards in various states.

For more information on N031 Air and Water Monitoring: World Market, click on:  http://home.mcilvainecompany.com/index.php/markets/2-uncategorised/106-n031.

Utility E-Alert Tracks Billions of Dollars of New Coal-fired Power Plants on a Weekly Basis

Here are some headlines from the Utility E-Alert.

UTILITY E-ALERT

#1271 – May 6, 2016

Table of Contents

POWDER BULK SOLIDS SHOW

·       More Focus on Products for Coal-fired Power

·       The importance of FIFO vs. LIFO in Dust Cake

·       Valve Displays were Impressive

COAL – US

·       OG&E receives approval for Dry Scrubber at Sooner Coal-fired Power Plant

·       Dynegy to shut down Multiple Central and Southern Illinois Coal-Fueled Units

COAL – WORLD

·       Malaysia Commissions 1-GW Ultra-supercritical Coal-fired Power Plant

·       Chinese firm to restart Myanmar’s Tigyit Coal-fired Power Plant

·       Turkey to introduce Incentives, Environmental Exemptions for Coal-fired Power Plants

The 41F Utility E-Alert is issued weekly and covers the coal-fired projects, regulations and other information important to the suppliers. It is $950/yr. but is included in the $3020 42EI Utility Tracking System which has data on every plant and project plus networking directories and many other features.

 McIlvaine Hot Topic Hours (HTH) and Recordings

     Explanation          Applicable Services         Schedule & Registration       Sponsored Webinars 

McIlvaine conducts periodic webinars which are in a discussion format and are free of charge to all participants. The displayed material and recordings are free to purchasers of the products and services and by subscription to others.

Format:  50-90 minute recorded discussion using McIlvaine display material. The session will be free of charge to all participants but registration is required.

Approach: There are two types of webinars. One is focused on Markets and directed to suppliers. The other is focused on aiding purchasers make the best Decisions relative to purchases of flow control and treatment equipment and services.

Markets HTH
The general overviews of the market including size and major variables will be discussed with heavy emphasis on technology and regulatory drivers.  The presentation will be based on the latest information appearing in McIlvaine multi-client reports. Questions and views from both subscribers and non-subscribers are encouraged.

Decisions HTH
McIlvaine has been publishing information systems on pollution control since 1974.  Each subject is organized by the pollutant control technology e.g. fabric filter, scrubber, etc. There are search capabilities to retrieve information on any application.  The newest addition has been slide deck systems displaying the issues and options relative to a specific applications.  Coal-fired power, cement, steel and waste combustion decision slide decks are continually updated.

The continually updated slide decks are displayed on the applicable decision system.  It is recommended that participants view the slide deck in advance of the session and be prepared with questions and views.

Value to purchasers and specifiers:  Your questions and interests will be prioritized in the discussion. You will get a monthly newsletter and have continuing access to the system and multiple ways to interface in the future along with a networking directory of suppliers.

Value to Suppliers:  You have the opportunity to provide data to be considered at no charge. If you are also a subscriber you will see the summaries in advance and be able to shed light on issues and options not properly covered in the slide deck.  If you are a subscriber you will receive the monthly newsletter and continuing yearly access to the system including networking directories.

44I Power Plant Air Quality Decisions  includes 1ABC, 3ABC, 4ABC, 9ABC decision services but not 2ABC. So those with multiple technologies and at least partial focus on power will find this combination most cost effective.

HOT TOPIC HOUR (HTH) SCHEDULE

Dates for the next 6 meetings are firm; the others will be held in sequence at approximately two week intervals.  Unforeseen developments could dictate the insertion of new subjects.

Click here to Register for the Webinars

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You can register for our free McIlvaine Newsletters at: http://home.mcilvainecompany.com/index.php?option=com_rsform&formId=5.

Bob McIlvaine
President
847-784-0012 ext. 112
rmcilvaine@mcilvainecompany.com
www.mcilvainecompany.com