Posted by Andy Bartocci on Tue, Oct 04, 2011 @ 03:56 PM
In 2009 I gave a paper at International Conference on Thermal Treatment Technologies (IT3) on a wet electrostatic precipitator (WESP) system for the Quemetco secondary lead smelting facility in Southern California. It was explained that the system was an add-on control to help the plant meet a cancer risk index by removing low concentrations of metals. The facility was meeting stack emission limits and had similar control technology used by other facilities in the industry including bag-houses,
HEPA filters, and wet scrubbers. Because residential neighborhoods had moved closer to the boundaries of the plant over the years, the stack emission limits were insufficient to meet the cancer risk index. In other words, the facility had to achieve lower emission levels than other similar plants. The WESP system was installed in 2007 and provided a performance guarantee for arsenic, lead, and nickel which were the larger contributors to the cancer risk index.
In May 2011, the EPA released the new National Emissions Standards for Hazardous Air Pollutants (NESHAP) for secondary lead smelting facilities. The report sites in section III.B.2 that two of the 14 secondary lead smelting facilities have estimated actual lead emission only moderately lower than the allowable emission level (about 2-3 time lower). The majority of the other facilities have estimated actual emissions in the range of 10 to 100 times lower than allowable. However, one facility with highly advanced controls has an estimated actual emission of about 1,500 times below allowable emission levels. This facility is the Quemetco facility operating with a WESP system. It can be surmised the plant is achieving emission levels 15 to 150 times lower than the other lead smelting facilities.
In June of 2010 a public letter on behalf of RSR Corporation (Quemetco) was presented to Mr. Charles French, Metals and Minerals Group, of the EPA. The letter states that the WESP system yielded dramatic reductions in air emissions from its operations. The cancer risk was reduced by 87% to 2.88 cancer cases in one million exposed individuals over a 70-year evaluation period. Prior to installation of the WESP, Quemetco emitted 615 pound of lead annually. The letter reports that lead emissions plummeted to 1.22 pounds per year – a 99.8 percent reduction. A table is provided in the letter that summarizes significant reductions of other hazardous air pollutants. Some of the reported metals reductions include the following:
|
Pollutant
|
Pre-WESP Emissions (lb/yr)
|
Post-WESP Emissions (lb/yr)
|
Percent Reduction (%)
|
|
Lead
|
614.95
|
1.22
|
99.8
|
|
Arsenic
|
96.01
|
1.59
|
98.3
|
|
Nickel
|
7.07
|
0.18
|
97.5
|
|
Cadmium
|
6.55
|
0.53
|
99.2
|
|
Chromium (VI)
|
0.33
|
0.06
|
81.8
|
|
Dioxins
|
0.0004
|
3.83 x 10-7
|
99.9
|
The data presented in the letter is consistent with the initial stack test data that was shared with Envitech following the installation. Although the system provided a guarantee for only three metal compounds, we expected similar removal for any condensed metal at the inlet of the WESP. The data demonstrates this was the case.
The consistent performance since the installation in 2007 demonstrates the tremendous capability of the WESP system to achieve dramatic reductions of condensed metals in a robust fashion for a process that must operate 24/7/365 days per year.
Posted by Andy Bartocci on Fri, Jun 10, 2011 @ 01:44 PM
Last month I attended the 30th International Conference on Thermal Treatment Technologies & Hazardous Waste Combustors (IT3). The conference was held May 10-13 in Jacksonville Florida. The IT3 Conference provides a forum for the discussion of state-of-the-art technical information, regulations, and public policy on thermal treatment technologies and their relationship to air emissions, greenhouse gases and climate change. Envitech has been a long time participate of the conference dating back to our founding in 1994 and this year was a sponsor for the annual meeting.
It was announced during the Program Advisory Committee (PAC) meeting that I will be the new Vice Technical Chair for the conference. Roy Cross of AMEC (formerly MACTEC) will hold the past Chair position and Gary Elliott of Lafarge North America will be the acting chair. I look forward to working with this group to plan next year’s conference and to help the conference grow.
This year’s conference had several worthwhile technical tracks ranging from Biomass, Waste-to-Energy, Alternatives to Incineration, and Multi-Metal CEMs. Particularly noteworthy were the sessions on Regulators Perspective on HWC MACT Implementation and An Introduction to Recently Announced Combustion MACT Regulations. These sessions were haired by Mel Keener of the Coalition for Responsible Waste Incineration (CRWI) and co-chaired by Heather McHale of Coterie Environmental. The sessions were well attended by conference attendees. The Regulators Perspective included 3 U.S. EPA representatives, Frank Behan, Charlie Hall – Region 5, and Kishor Fuitwala – Region 6, as well as to representatives from Alabama Department of Environmental Management (DEM). The session on MACT regulations included the, non-hazardous solid waste rule, industrial boiler and process heater rule, commercial and industrial solid waste incinerator rule, Portland cement rule, Hospital/Medical/Infectious Waste Incineration Rule, Sewage Sludge Incinerator Rule, and the Electric Utilities rule. Many of these rules had recent updates that will impact owners/operators. The presentations were designed to explain the impact and timelines or the recent rule changes.
Posted by Andy Bartocci on Tue, May 03, 2011 @ 04:41 PM
I posted previous blogs discussing the South Coast Air Quality
Management District (SCAQMD) Regional Clean Air Incentives Market RECLAIM program and the A&WMA/AQMD SOx Control Technology Conference held at Diamond Bar, CA on March 17th. During the conference I participated as a panel member to present Envitech’s Ultra-Low SO2 scrubber design. I will also be giving this presentation at the upcoming International Conference on Thermal Treatment Technologies (IT3) in Jacksonville, FL, May 10-13, 2011 and again at the Annual Air & Waste Management Conference in Orlando, FL June 21-24, 2011. Envitech will have a booth at the IT3 conference.
Below is an abstact for discussing the Ultra-Low SO2 scrubber design. You can click the icon below to download the paper.
High Efficiency SO2 Scrubber Design to Reduce Caustic Consumption
ABSTRACT
An industrial facility located in Southern California operates a thermal oxidizer to treat vapor recovery and waste gas streams containing sulfur compounds. The facility has an available source of alkali waste water which could be a potential scrubbing solution. Several technologies were evaluated to replace the existing control equipment for reducing SO2 emissions. Incentives exist for similar facilities with the South Coast Air Quality Management District (SCAQMD) Regional Clean Air Incentives Program (RECLAIM) to reduce SOx emissions below the facilities operating permit limits. The RECLAIM program is requiring plants to achieve less than 5 ppmv SO2 stack emissions and greater than 99% SO2 removal.
Plans are currently underway to replace the existing control equipment with a two stage packed bed scrubber system. This arrangement enables the plant to achieve very low emission limits and reduce caustic consumption by as much as 28% compared to a single stage scrubber. It also provides flexibility for future use of available alkali waste water to reduce caustic consumption by as much as 75% compared to a single stage caustic scrubber. This reduction will save an estimated $165,000 per year in operating cost. This paper will discuss the system design and how it achieves low outlet emissions while reducing overall chemical consumption. It will also discuss several other design considerations and benefits. The design approach provides a viable alternative for other Southern California facilities impacted by the SOx RECLAIM program as well as facilities in other regions.
Click on below icon to download whitepaper.
Posted by Andy Bartocci on Thu, Mar 24, 2011 @ 06:58 PM
This is a follow-up to my blog post last week on SOx scrubbers and the AQMD RECLAIM program. I was a panel member during 
one of the conference sessions for the SOx Control Technologies & Emissions Monitoring for Stationary Sources hosted by AQMD and the Air & Waste management Association (A&WMA). The conference was held on March 17th at the South Coast AQMD facility in Diamond Bar, CA. There were about 90 attendees at the conference and my understanding is that all but one of the 11 major facilities impacted by the AQMD RECLAIM program had someone in attendance.
There were interesting presentations given in the morning sessions focused primarily on refinery applications. These included presentations by both INTERCAT and GRACE on additives that can be used in Fluid Catalytic Cracking Units (FCCU’s) to reduce SOx emissions without add-on controls. This type of approach will likely be used by most of the local refineries to meet shorter term requirements. However, the speakers noted limitations for achieving lower outlet emissions in the 5 ppmv range. These can include higher chemical consumption and impacts on opacity. This suggests there may still be a need for back end controls to meet longer term requirements to achieve limits below 5 ppmv.
PRAXAIR gave an informative presentation introducing their Refinery Gas Processor (RGP) technology. This technology is targeted at treating non-H2S sulfur compounds (Mercaptans, COS/Sulfides, Disulfides, Thiophenes) for use in conjunction with existing amine H2S removal systems. The RGP technology can enable a 90% reduction of non-H2S sulfur from refinery fuel gas.
Another issue discussed during the conference was the ability accurately measure and report outlet emissions as low as 5 ppmv. This will present a challenge for many facilities because most existing monitoring equipment are designed for measuring outlet emissions at higher concentrations. However, several panel members from the afternoon session on emissions measurements provided useful information on how to address these challenges. These include presentations from:
I gave a talk during the afternoon session on control technologies. This session was dedicated to wet scrubber technology for achieving ultra-low SOx emissions. Ultra-low is loosely understood to be less than 5 ppmv. This is generally a longer term target for the AQMD RECLAIM program. Most the technologies focused on wet gas scrubbers for refinery FCCU units. I presented an innovative SOx scrubber design to remove SO2 from a thermal oxidizer exhaust at an industrial facility located in Southern California. The exhaust contains more than 1,000 ppm of SO2 and the facility is required to achieve less than 5 ppmv with greater than 99% removal efficiency. There are several advantages of the scrubber design for applications requiring ultra-low SO2 emissions. The scrubber design may be a viable option for some of the facilities impacted by the AQMD RECLAIM program including FCCU units and glass manufacturers. I’ll provide a future blog post that gives more information about the ultra-low SO2 scrubber design.
Posted by Andy Bartocci on Mon, Mar 14, 2011 @ 04:08 PM
A hot topic right now in California is the South Coast Air Quality Management District (SCAQMD) Regional Clean Air Incentives
Market (RECLAM), adopted in October 1993. The purpose of the RECLAIM program is to reduce NOx and SOx emissions through a market-based program. Reduction of these pollutants helps reduce smog and improve visibility. Recent proposed amendments will affect eleven major facilities which emit and estimated 93% of the total emissions from the SOx RECLAIM facilities. These amendments will require many facilities to reduce SOx emissions below the level of control they currently have in place. Financial incentives exist for other facilities to reduce emissions below existing permit limits.
The West Coast Section of the Air & Waste Management Association (A&WMA) is hosting a technical conference on innovative SOx control strategies and technologies for stationary sources on March 17-18, in Diamond Bar, CA. Part of the conference is dedicated to providing an overview of the regulatory landscape including new federal rul
es related to SOx and the recently amended SOx RECLAIM program. I will be giving a presentation on an innovative SO2 scrubber design used at an industrial facility in Southern California to remove SO2 from a thermal oxidizer. The SO2 scrubber is designed to achieve low outlet emissions below 5 ppmv and greater than 99% removal efficiency. The presentation will discuss the advantages and benefits of the design, including reduction in caustic consumption. Continued efforts to deploy better technology and reduce emissions will enable clearer skies in the face of growing populations.
Photo Credit, LA Smog - Recursive_1
Photo Credit, LA Clear Day - Nomadlovebird
Posted by Andy Bartocci on Tue, Jul 13, 2010 @ 01:57 PM
I gave recent presentations at the International Biomass Conference in Minneapolis, MN and the International Thermal
Treatment (IT3) Conference in San Francisco, CA on wet scrubbers for gasification. Below is the paper abstract. A free download of the paper and presentation is available by clicking the links below. The paper discusses two common tar management approaches regarding syngas cleaning:
- Thermal Tar Destruction Systems
- Tar Removal Systems
ABSTRACT
Concern for global climate change coupled with high oil prices has generated new interest in renewable energy sources. Many innovative companies are working to commercialize these sources using gasification to convert waste to energy and fuels. Gasification is a thermal conversion process which produces synthetic gas (syngas). With proper cleaning, syngas can be used to fuel an internal combustion engine (ICE) to drive a generator, and produce electricity. Waste heat is recovered from the system to improve the overall plant efficiency.
During gasification, various pollutants may be produced depending on the type of gasification process and the make-up of the waste feedstock. The feedstock can vary from biomass, municipal solid waste (MSW), to even medical or hazardous waste. The pollutants involved can include large to sub-micron particulate matter, tars, and acid gases. A key challenge to commercializing gasification is designing a syngas cleaning system that removes pollutants to a level that is tolerated by the ICE (or fuels and chemical production system) and also meets emission standards. This paper will discuss different approaches to tar removal and control strategies for the various pollutants.
Please click on the below icons to download the IT3 conference white paper and the International Biomass Conference presentation.
Posted by Andy Bartocci on Tue, Jul 13, 2010 @ 01:57 PM
I gave recent presentations at the International Thermal
Treatment (IT3) Conference in San Francisco, CA and the AWMA Conference in Calgary, Canada. The paper is co-authored with Liran Dor, CTO of EER - Environmental Energy Resources Ltd. The paper discusses an environmentally friendly way of converting medical waste to energy using EER’s Plasma Gasification Melting (PGM) and Envitech’s wet scrubbing technology.
ABSTRACT
A plasma gasification melting (PGM) technology has been developed to transform waste into synthesis gas and products suitable for construction materials. The core of the technology was developed at the Kurchatov Institute in Russia and has been used for more than a decade for the treatment of low- and intermediate-level radioactive waste in Russia. It is applicable to municipal solid waste (MSW), municipal effluent sludge, industrial waste and medical waste.
Plans are currently underway to build a plant in the US to recycle medical waste using the PGM technology into a high calorific Syngas and a benign residue. Both output materials may be considered secondary materials since they have commercial use in other processes. Current plans include the production of steam which will be sold as a commodity to nearby industrial users.
The Syngas is fed into a Heat Recovery Steam Generator (HRSG) to produce superheated steam for use as heat or electricity generation using a steam generator. The Syngas leaving the HRSG will enter an Air Pollution control (APC) system for post process gas cleaning. The APC system will use a wet scrubber system that has successfully achieved low emission standards on other typical combustion processes. This paper will discuss how these technologies are combined to create an economically viable and environmentally friendly solution for converting medical waste into energy.
Please click on the below icon to download the AWMA and IT3 conference white paper.
Posted by Andy Bartocci on Tue, Jul 13, 2010 @ 08:53 AM
I gave recent presentations at the International Thermal Treatment (IT3) Conference in San Francisco and the Annual AWMA conference in Calgary, Canada that discusses the new hospital/medical/infectious waste incineration (HMIWI) MACT standard and implications for existing systems. Below is the abstract. A free download is available by clicking on the link below. The paper presents emissions data on several scrubber systems and discusses how these relate to the new rules. I also discuss cost effective strategies to comply with the new rules using add-on controls.
ABSTRACT
On October 6th, 2009, proposed revisions to the New Source Performance Standards (NSPS) and Emission guidelines (EGs) for the Hospital/Medical/Infectious Waste Incinerators (HMIWI) Standards became final. These regulations, originally promulgated in 1997, were established under Section 129 of the Clean Air Act (CAA) and serve as the maximum achievable control technology (MACT) standards for hospital, medical, and infectious waste incinerators.
Wet scrubbers are currently used on many hospital, medical, and infectious waste incinerators in the United States. The new emission limits exceed the design capability of most of these systems, primarily with respect to particulate matter (PM), lead (Pd), cadmium (Cd), and mercury (Hg). As a consequence, new control strategies are needed to meet the more stringent standards.
This paper presents a cost effective control strategy for meeting the new limits and discusses how the strategy has been implemented on similar hazardous waste incinerator scrubbers.
Please click on the below icon to download a white paper on this topic: "Wet Scrubber Control Strategy to Meet the New Hospital/Medical/Infectious Waste Incinerator Standard"
Photo Credit: bravosixninerdelta
Posted by Andy Bartocci on Tue, Jun 08, 2010 @ 07:59 AM
The US Department of Energy (DOE) has funded R&D in coal gasification in recent years as part of a strategy to reduce green
house gases. One aspect of this technology is the use of coal dryers to dry the coal before feeding it into the gasifier. This requires a coal dryer scrubber which can be comprised of a Venturi scrubber followed by a condenser tower shown in the sketch.
The exhaust gas from the dryer passes through a Venturi scrubber for particulate removal then through a condenser tower to condense water vapor in the gas stream. The gas passes through a mist eliminator at the top of the condenser tower to remove water droplets in the gas stream. Re-circulated water in the Venturi throat is collected in the sump of the condenser
tower. Gas flow rates for these processes are relatively large and can exceed 300,000 acfm. Because of the large gas flows, the condenser tower can be as large as 20 feet in diameter or larger. The Venturi scrubber (shown in the image on the left) must have a special throat design to account for the large gas flow rate. The Venturi throat design is discussed in in the previous blog post for Venturi Scrubber Throat Design for Large Gas Flow Processes.
Posted by Andy Bartocci on Mon, May 03, 2010 @ 09:36 AM
In previous blog posts, I have discussed how a key to particle collection in a Venturi scrubber is maintaining uniform water distribution across the Venturi throat to collide with particles. This presents a challenge for large volumetric gas flow rate processes. The difficulty becomes getting water across a large cross sectional area without any void spaces for particles to escape through. Often times, the solution may be to simply split the gas flow into multiple trains. However, this increases capital costs for additional ductwork and piping and takes up more real estate. It is always desirable to minimize the equipment footprint and maintain the gas flow in one train.
To achieve this objective, Envitech uses a proprietary Venturi throat design that has been used on large gas flow rates processes, including foundries and purified teraphthalic acid (PTA) plants. The proprietary design has an internal construction that ensures uniform water distribution throughout the Venturi throat cross sectional.
The adjacent image shows a picture of an Envitech Venturi/Quencher constructed from Hastelloy C276 used for a PTA plant with a gas flow rate of 530,000 acfm. This type of Venturi design may be used on other large gas flow rate processes like a coal dryer system for a coal gasification plant which can have a gas flow rate as large as 300,000 to 400,000 acfm.