Thursday, September 22, 2016

EPA finalizes reconsidered issues in Area Source Boilers Rule

This month, EPA set forth its final rule on the issues for which reconsideration was announced on Jan. 21, 2015 that pertained to aspects of the February 2013 final amendments to the National Emissions Standards for Hazardous Air Pollutants for Area Sources: Industrial, Commercial and Institutional Boilers in the Area Source Boilers Rule.
The provision that pertains to biomass-fired boilers is the one that eliminates further performance testing for particulate matter (PM) for certain boilers based on their initial compliance test. EPA has now finalized an alternative provision to require PM performance testing once every five years when initial compliance tests show that PM emissions are equal to or less than half of the limit instead of totally eliminating further PM performance testing.

Monday, September 12, 2016

Stack Testing – Method 202 Particulate

We always say that a picture is worth a thousand words. It perfectly applies in this Method 202 residue study.

Thursday, September 1, 2016

US Army, Hawaiian Electric Break Ground on Bioenergy Facility

On Aug. 22, the U.S. Army and Hawaiian Electric Co. broke ground on a 50 MW power plant that will run on a mixture of biofuel and conventional fuels. The facility is scheduled to be operational by spring 2018.

Full article:

Court Vacates Portion of EPA's MACT Rule

On July 29, the U.S. Court of Appeals for the D.C. Circuit issued an opinion on a lawsuit regarding the U.S. EPA’s Boiler Maximum Achievable Control Technology (MACT rule), vacating certain elements of the rule.

Full article:

Thursday, April 21, 2016

Particulate Emissions Measurement

Particulate emissions measurement has long been a topic of nuanced discussion about how the manner of measuring the matter influences results.  The following discussion thread from the Source Evaluation Society's LinkedIn group covers some of those nuances.

Wednesday, April 20, 2016

Three Lessons in Innovation from Jeff Bezos

In a service industry driven by slow-moving Federal regulations, the first two lessons may be a bit less applicable, but #3 is universal.

The foundation of customer care is in the name: care about what your customers need and want. Anticipating their needs is essential to the framing that you build on top of that foundation.

Monday, March 28, 2016

Back to the Basics - Analyzing Oxides of Nitrogen (NOX)

Back to the Basics - Analyzing Oxides of Nitrogen (NOX)

Steve Hartman, Golden Specialty

The basic principle:
The chemiluminescent (a fancy way of saying light given off by a chemical reaction) NOX analyzer reacts NO with O3 (Ozone) to form NO2, O2 and light. The light comes from the decomposition of the O3 to O2. When air is passed through the ozonator, which is just a very high energy spark chamber, some of the oxygen atoms are excited by the high voltage to a higher energy state. Electrons in some of the oxygen atoms are moved into higher orbital shells and as such are able to then form the ozone molecule. But ozone is unstable and seeks to return to the stable O2 form. This is accomplished when it meets an NO molecule, the spare Oxygen is transferred forming NO2, and the extra energy that was stored in the O3 molecule is emitted as a photon of light as all those oxygen atoms go back down to their normal energy state.

There’s more to it:
The NOX converter comes into play because since the analyzer works by reacting NO with O3 to form NO2, if you already have NO2 in the sample you won’t see it. So the NOX converter, which operates at very high temperature, thermally breaks down the NO2 back into NO and O2 which can then be reacted with ozone and read.

The analyzer won’t work at all without an ozonator.  It will only read NO and not NOX without a working converter.

Still more about NOX converters:
There are two types of NOX converters, straight thermal and catalytic. The straight thermal is Stainless steel and operates around 600 - 650°C.  it breaks down the NO2 by temperature alone. The catalytic, usually made of a Chromium / Molybdenum steel, and called a Moly converter, operates much cooler, around 400°C. It relies on the catalyst to help break down the NO2, but since it is a catalyst, it gets used up over time.  When it has reached the end of the catalyst’s life it quits working. Moly converter service life is rated in ppm hours. If you had one with say a 10,000 ppm hour life, that would mean that it would operate for 10,000 hours with a 1 ppm NO2 concentration, but only 10 hours with a 1,000 ppm NO2 concentration. On a combustion turbine, NO2 is typically pretty low, except during startup when it can be 50% or more of the total NOX emissions. Many utilities have run into trouble trying to pass certification audits on turbine exhaust analyzers because their analyzers had Moly converters, which were quickly consumed.

So if a Moly converter gets used up and you don’t know whether it’s working, why would you use one in the first place? Good question, grasshopper.  The down side of a high-temperature of the Stainless converter is that it will break down ammonia causing it to be read as NOX, and giving a falsely high reading. This can be a problem on combustion sources using ammonia injection for reduction of NOX emissions.  In this case Moly is the best choice as it operates below the temperature to break down ammonia and the catalyst doesn’t react with ammonia.