Air Pollution Control Innovations

Thermal Oxidizer HCl Scrubbers for Vinyl Chloride Facilities

Posted by Andy Bartocci on Mon, Apr 12, 2021 @ 08:30 AM

Illumina HCl ScrubberHCl emissions are encountered in a wide range of applications including hazardous waste combustors (HWC), medical waste incinerators, pharmaceutical production, and ceramic tile manufacturing. There is a wide range of performance requirements depending on the application and applicable state or US EPA standard. Below is a summary of performance requirements for some of these applications.

  • Hospital, medical, and infectious waste incinerator (HMIWI) MACT standard: 5.1 to 15 ppmv depending on the size of the incinerator and whether it is an existing or new incinerator.
  • Hazardous waste combustor (HWC) MACT standard: 32 ppmv for existing incinerators and 21 ppmv for new incinerators; adjusted to 7% O2.
  • Ceramic tile kiln scrubber: > 97% removal
  • Pharmaceutical manufacturing RTO scrubber: > 99% removal
A specific HCl application is the National Emission Standards for Hazardous Air Pollutants (NESHAP) for Polyvinyl Chloride and Copolymers (PVC) Production. The US EPA has granted petitions for reconsideration of the emission limits in the 2012 final rules for process vents, process wastewater, and stripped resin for major and area sources. A typical exhaust source from these facilities is treated by a thermal oxidizer followed by a quencher and a packed bed scrubber.  HCl loads are high and can range from 10,000 ppmv to peak loads of 25,000 ppmv. The proposed new NESHAP rule reduces HCl limits from 78 ppmv to 0.64 ppmv for existing sources. New sources must meet an emission limit of 0.17 ppmv. These are challenging limits and require greater than 99.998% removal efficiency.

Dal_Tile_installIt is well known that gaseous HCl readily absorbs into water and can be removed with high efficiency with caustic addition. The challenge however is that a fraction of the inlet HCl condenses into acid aerosol when hot gas from the thermal oxidizer contacts water in the quencher. The aerosol quantity formed and the particle size distribution (PSD) of the acid droplets vary from process to process. Predictive models to accurately estimate these values are limited and imprecise. In some cases as much as 20% of the HCl can form an acid aerosol fog. Aerosol carry-over exhausting from the scrubber will show up in stack tests and contribute to plant emissions.

It is common for HCl scrubbers to utilize mesh pads above the packed bed to remove aerosol droplets before exiting the scrubber. As noted above, many applications require 97% to 99% removal efficiency. This arrangement is generally adequate for these removal efficiencies. The proposed NESHAP standards for vinyl chloride facilities, however, requires higher efficiency. This increased efficiency demand requires additional consideration in the scrubber design and mist eliminator to guarantee performance. Facilities should rely on experienced scrubber suppliers that understand HCl aerosol and account for it in the scrubber design to guarantee emission limits.

Click on the link below to download HCl scrubber literature.

Download Literature

Topics: Scrubbers, Incinerator Scrubber, quenchers, Packed Bed Absorbers, Packed Bed Scrubbers, Wet Scrubbers, HCl Scrubbers

HCl Scrubbers for Regenerative Thermal Oxidizers (RTO's)

Posted by Andy Bartocci on Wed, Mar 24, 2021 @ 11:05 AM

Regenerative thermal oxidizer’s (RTO’s) are thermally efficient devices used to destroy low concentrations of volatile organic compounds (VOC’s). Chlorinated compounds, if present, oxidize into hydrochloric acid (HCl) which must beIllumina HCl Scrubber removed after the RTO.

Two examples are Carestream Health in Rochester, NY, a health care products supplier, and Illumina in San Diego, CA, a biotechnology provider.  Facilities at both companies generate low concentrations of chlorinated VOC’s.  Control devices are needed to remove HCl emissions downstream of RTO’s used to meet VOC emissions.

Envitech packed bed absorbers were selected to treat the RTO exhaust gases.  The first step in the scrubbing process is an evaporative quencher to cool the gas to saturation.  A horizontal quencher simplifies ductwork and installation cost.  Al6XN construction provides corrosion resistance.es are Carestream Health in Rochester, NY, a health care products supplier, and Illumina in San Diego, CA, a biotechnology provider.  Facilities at both companies generate low concentrations of chlorinated VOC’s.  Control devices are needed to remove HCl emissions downstream of RTO’s used to meet VOC emissions.Envitech packed bed absorbers were selected to treat the RTO exhaust gases.  The first step in the scrubbing process is an evaporative quencher to cool the gas to saturation.  A horizontal quencher simplifies ductwork and installation cost.  Al6XN construction provides corrosion resistance.  

The quencher is followed by a fiber reinforced plastic (FRP) vertical packed bed absorber with gas flowing vertically upward, counter current to downward flowing water.  Excess water from the quencher and packed bed collects in the absorber sump and recirculates to the quencher and packed bed.  A dilute caustic solution (NaOH) is injected into the discharge side of the recirculation pump to neutralize HCl.  A blowdown stream purges the system of reaction products.   Caustic injection and blowdown are controlled by pH and oxidation reduction potential (ORP).

Gaseous HCl readily absorbs into the scrubber recirculation liquid.  A fraction of the HCl forms a submicron aerosol as gas contacts water in the quencher to cool the gas.  The aerosol is removed by a properly designed mist eliminator.  Gas calculations are used to estimate the fraction of acid aerosol based on gas dew point and partial pressures of water and acid.  The mist eliminator must be capable of removing aerosol at the expected concentration and droplet size distribution. This  impacts the mist eliminator selection, vessel size, and pressure drop of the system.

The scrubbers were put into service and effectively operate on a continuous basis with minimal operator management. Operating parameters and performances are summarized below.

Design Carestream, NY Illumina, CA
Flow, acfm 6,000 4,000
Inlet Temp, oF 585 230
Inlet HCl, lb/hr 92 10
HCl Removal Efficiency, % 99 99

Click on the link below to download literature about this application.

Download Literature

Topics: Scrubbers, Incinerator Scrubber, quenchers, Packed Bed Absorbers, Packed Bed Scrubbers, Wet Scrubbers

Oxygen Strippers Using Natural Gas

Posted by Andy Bartocci on Tue, Jun 09, 2020 @ 08:30 AM

Oxy Petroleum Stripper TowersVintage Petroleum, LLC, a subsidiary of Occidental Petroleum Corporation operates oil and gas fields in Lost Hills, California, northwest of Bakersfield. The fields operate steam boilers that use nearby canal water. High concentrations of dissolved oxygen in the canal water caused excessive corrosion in the boilers.

Vintage was looking for an effective means to reduce oxygen content in the canal water to prolong boiler life and reduce maintenance costs.

The customer selected Envitech to design and build two stripper towers. The towers use high pressure natural gas to strip oxygen from the canal water. The water is pumped 1,000 feet from the canal to the tower locations. After stripping to remove oxygen, the water is pumped to an existing fresh water tank.

The vessels are constructed of carbon steel with a 3/16 inch corrosion allowance and painted internally and externally. The
vessels are fabricated in accordance with ASME Code Section VIII Division I requirements and stamped. The maximum vessel design working pressure is 100 psig at a maximum design temperature of 300 °F and also designed for half vacuum.

The lower vessels are 6 feet in diameter. The upper packed bed sections are 4 feet in diameter. The overall vessel height is 27 feet.

The first system was installed in 2013. The second system was installed in 2014. Both systems are operational and the facility reports success in prolonging boiler life. Designed to the parameters summarized in the adjacent table, the stripping towers resulted in an innovative process solution to solve a unique operational problem.

  • Gas flow rate, mscfd: 328
  • Water flow rate, gpm: 450
  • Operating temperature, oF: 60 to 120
  • Operating pressure, psig: 40
  • Oxygen content of in stripping gas, ppm: 70
  • Dissolved oxygen content in canal water, mg/L: 9
  • Dissolved oxygen removal: > 90%

Click on the link below to download literature about this application.

Download Literature

 

 

Topics: particulate control, Scrubbers, Incinerator Scrubber, quenchers, Packed Bed Absorbers, Packed Bed Scrubbers, Wet Scrubbers

Auto Shredder RTO and Acid Gas Scrubber

Posted by Andy Bartocci on Tue, Jun 02, 2020 @ 08:30 AM

The metal recycling industry provides tremendous societal benefit by preserving natural resources and reducing greenhouse gases. Metal recycling entails pulverizing and shredding vehicles and appliances into smaller pieces to facilitate melting processes. Large mega shredders are often eAuto Shredder RTO Scrubber_Browsenclosed to capture process emissions. Volatile organic compounds (VOCs) and other hazardous air pollutants (HAPs) are released during shredding, including small amounts of halogenated compounds.

In recent years, some state and regional regulatory agencies have begun requiring Best Available Control Technology (BACT) to treat shredder exhaust gases for VOCs and other HAPs. One facility had a need to treat a large volumetric flow rate from their shredder enclosure. The equipment must meet stringent performance limits, be reliable, and capable of 24/7 operation.

Envitech partnered with Process Combustion Corporation (PCC) to provide a comprehensive BACT solution. The partnership leverages PCC’s 50 years of experience engineering thermal systems for air pollution control with Envitech’s wet scrubber expertise. PCC provided a regenerative thermal oxidizer (RTO) for VOC control and interconnect ductwork and incorporated an Envitech packed bed acid gas scrubber system. The scrubber scope of supply includes two (2) equal trains consisting of a horizontal Hastelloy C276 quencher, 13 foot diameter fiberglass packed bed absorber, instruments, pre-assembled recirculation pump skid with redundant pumps, and stack.

The horizontal quenchers ensure the gas is fully saturated across all operating conditions and simplifies ductwork between the RTO and scrubber.

CFD modeling minimizes pressure drop and prevents re-entrainment.

The system will be installed and operational in 2021. Guarantees are provided to meet the below design conditions. The combined PCC/Envitech process provides a reliable, comprehensive solution to meet the demands of a more stringent regulatory environment.

  • Gas flow rate: 140,000 acfm
  • VOC destruction: > 98%
  • Acid gas removal (HF and HCl): > 99.5%
Click on the link below to download literature about this application.

Download Literature

Topics: particulate control, Scrubbers, Incinerator Scrubber, quenchers, Packed Bed Absorbers, Packed Bed Scrubbers, Wet Scrubbers

Thermal Oxidizer Quencher Treating Silicon Dioxide (SiO2) Particulate and HCl

Posted by Andy Bartocci on Wed, May 27, 2020 @ 07:26 AM

A pharmaceutical company, Roche Carolina, operates a thermal oxidizerThermal oxidizer SiO2 Quencher (TO) that treats a rich stream of chlorinated compounds and an organic silicon compound. HCl and silicon dioxide (SiO2) particulate are formed during combustion. The exhaust is treated by a Hastelloy evaporative quencher followed by a caustic scrubber.

The quencher utilizes spray pig tailed nozzles, some of which are orientated upward into the gas to prevent fouling from SiO2 accumulation on the spray headers. The pigtails gradually plug both inside and outside as SiO2 particulate collect outside the nozzles.

The stainless inlet duct flange connection frequently springs leaks, causing shutdowns for repairs. It was thought that the upward pointed nozzles wetted the welded flange surfaces resulting in acid gas corrosion from HCl and possible stress from thermal expansion differences between the two metals.

An improved design was sought to increase reliability and eliminate operational and maintenance problems. The design needed to address the potential for:

    • Spray nozzle plugging from SiO2 particulate.
    • SiO2 accumulation on the quencher walls.
    • Acid gas corrosion.
    • Weld leakage and failure.
The customer selected a custom engineered Envitech quencher.

Tangential pipes with large orifices at the top of the quencher keeps the walls fully wetted and prevents SiO2 particulate build-up.

A barrel at the inlet flange extends into the quencher with the same diameter as the inlet duct. The tangential nozzles are placed behind the barrel wall to protect injected water from traveling up into the duct.

Elimination of the pigtail nozzles prevents associated gradual nozzle plugging.

Because water is not put into the quencher-inlet duct interface, the possibility of leaking from this connection is eliminated. Risk of corrosion attack is also minimized.
Weld leakage and failure.

The bottom section is the same as the original design to facilitate integration.

The quencher has been operational since 2008 to the below design conditions. The facility reports good results and significantly improved reliability and lower maintenance costs.

  • Max flow rate, acfm: 6,700 acfm
  • Nominal flow rate: acfm 3,000 acfm
  • Max inlet temperature, oF: 850
  • SiO2 particulate, gr/dscf: up to 0.1
  • HCl, ppmv: 31
  • Saturation temperature, oF: 145

Click on the link below to download a case study and related quencher and wet scrubber literature.

Download Literature

Topics: particulate control, Scrubbers, Incinerator Scrubber, quenchers, Packed Bed Absorbers, Packed Bed Scrubbers, Wet Scrubbers

International Conference on Thermal Treatment Technologies and Hazardous Waste Combustors (IT3/HWC)

Posted by Andy Bartocci on Mon, Aug 26, 2019 @ 10:55 AM

IT3 Logo

Envitech will be attending and exhibiting at the 37th International Conference on Thermal Treatment Technologies and Hazardous Waste Combustors (IT3/HWC) in League City, TX on October 2nd and 3rd, 2019. If you happen to be attending the conference, please stop by the Envitech booth or find me at the conference to say hello.

Three keynote panels will include high level experts and cover hot topics in the industry:

  • PFAS Overview, Regulatory Approach, Testing and Destruction
  • Emerging Air Quality Monitoring
  • Lessons Learned from the United Kingdom's 2018 Novichok Nerve Agent Incident

Papers presented in technical sessions cover:

  • Technologies and Trends in Incineration
  • Plastics Recycle and Reuse
  • Emission Monitoring
  • Waste-to-energy, Emission Monitoring, Pyrolysis 

Envitech will present papers on the following two topics.

Technology Solutions for Sulfuric Acid Formation and Removal in Liquid Waste and Waste Gas Thermal Oxidizers

Petrochemical plants, refineries, and waste-oil re-refiners operate liquid waste or waste gas thermal oxidizers.Candle filter The thermal oxidizers need a wet scrubber to neutralize and remove SO2. Flue gas entering the scrubber contain some sulfur trioxide (SO3) which is converted to sulfuric acid (H2SO4) in the quencher. Sulfuric acid is a submicron liquid aerosol that passes through the downstream packed bed absorber. Some facilities are now being regulated for H2SO4. This paper evaluates and compares candle filters versus wet electrostatic precipitators (WESP’s) for H2SO4 removal in these applications.

Sewage Sludge Incinerator (SSI) Mercury Control Technologies

Mercury Control ScrubberWaste water treatment facilities operating sewage sludge incinerators (SSI) can reduce sludge volume and disposal costs by combusting dewatered sewage sludge. Emissions are regulated by the US EPA Maximum Available Control Technology (MACT) standard 40 CFR Part 60 and 62 to control particulate, lead (Pb), cadmium (Cd), SO2, HCl, dioxins/furans, and mercury (Hg). Many SSI’s need a control device specifically for mercury. This paper evaluates two mercury control technologies: sulfur‐impregnated activated carbon and Gore sorbent polymer catalyst (SPC) modules. Several facilities have used sulfur-impregnated activated carbon but safety issues have arisen due to fires which have shut down some systems. The Gore SPC modules are a relatively new technology with at least seven installations. A comparison is made of capital cost, operating cost, mercury removal efficiency, fire and performance risks based on incineration of 3,000 lbs/hr of sewage sludge. Finally, an overview is provided for an Envitech SPC mercury control scrubber operating at one facility.

Click on the icon below to download an Envitech brochure.

Download Brochure

 

 

Topics: particulate control, Scrubbers, SO2 Scrubber, wet electrostatic precipitators, Acid Gas, Incinerator Scrubber, SO3 Aerosol

Technology Solutions for Sulfuric Acid Formation and Removal in Thermal Oxidizers

Posted by Andy Bartocci on Fri, Aug 23, 2019 @ 02:56 PM

Enivtech will be attending the 2019 International Conference on Thermal Treatment Technologies andCandle filter Hazardous Waste Combustors  (IT3/HWC)  October 2-3 in Houston, TX. A paper will be given on “Technology Solutions for Sulfuric Acid Formation and Removal in Liquid Waste and Waste Gas Thermal Oxidizers”. The paper is available for download by clicking the button at the bottom of this blog piece.

Petrochemical plants, refineries, and waste-oil re-refiners operate liquid waste or waste gas thermal oxidizers. The thermal oxidizers need a wet scrubber to neutralize and remove SO2. Flue gas entering the scrubber contains some sulfur trioxide (SO3) which is converted to sulfuric acid (H2SO4) in the presence of water vapor. Sulfuric acid is a submicron liquid aerosol that can pass through downstream equipment, such as a packed bed absorber or a baghouse. Some facilities are now being regulated for H2SO4.

WESPOver the last decade, Envitech has supplied SO2 scrubbers for thermal oxidizers burning sulfur containing compounds in refining applications. Most of these do not have add-on controls for capturing sulfuric acid mist. More recently, however, Envitech has supplied two systems with candle filters for the capture of sulfuric acid mist. Another known system used a wet electrostatic precipitator for the capture of sulfuric acid mist. A potential fourth system with a large gas flow rate with expected SO3 emissions was evaluated for a wet electrostatic precipitator.

A thermal oxidizer converts sulfur containing liquid or gaseous waste in the presence of excess oxygen to sulfur dioxide (SO2). A fraction of SO2 is further converted to SO3. The reaction is:

SO2 + 1/2O2 => SO3

The conversion amount is influenced by many factors including the thermal oxidizer operating temperature, residence time, sulfur concentration, amount of excess air, and the presence of catalytic oxides and metal catalysts in the fuel. Literature suggests that even a well-performing thermal oxidizer still converts 1 to 5% of SO2 into SO3. Given the numerous factors influencing the formation of SO3¬, most designers select a conservative estimate of SO3 conversion, even when actual SO3 emissions have been measured, as variations in operation can generate substantially higher conversion.

Once formed in the thermal oxidizer, SO3 reacts with water in the downstream quencher to form sulfuric acid (H2SO4) by the reaction:

SO3(g) + H2O(l) => H2SO4(l)

At temperatures below 350°F, H2SO4 condenses into submicron liquid droplets which are difficult to remove because of their small size. Aerosol droplets pass through a quencher and packed bed absorber. A separate control device is needed for sulfuric acid removal that is suitable for submicron droplets.

Click on the link below to download the IT3/HWC conference paper to learn about “Technology Solutions for Sulfuric Acid Formation and Removal in Liquid Waste and Waste Gas Thermal Oxidizers”. The paper evaluates and compares candle filters versus wet electrostatic precipitators (WESPs) for H2SO4 removal in these types of applications.

Download Literature

Topics: particulate control, Scrubbers, SO2 Scrubber, wet electrostatic precipitators, Acid Gas, Incinerator Scrubber, SO3 Aerosol

Sewage Sludge Incinerator Mercury Control Scrubber

Posted by Andy Bartocci on Mon, May 13, 2019 @ 01:53 PM

A municipal waste water treatment plant operates a 2,750 lb/hr fluid bed sewage sludge incinerator (SSI). The Mecury Control Renderingincinerator had been shut down due to safety issues with the granulated activated carbon (GAC) mercury control scrubber. The plant sought expert help to evaluate and recommend a technology solution to replace the GAC and to get the SSI back in operation.

Based on extensive waste incineration gas cleaning experience, the facility contracted Envitech to evaluate the process, make recommendations, and implement a solution.

Envitech reviewedMercury Control Scrubber available literature and data to establish a conservative but justifiable design inlet concentration with sufficient capacity to meet a more conservative design condition without structural changes to the equipment.

An additional Envitech study compared W.L. Gore sorbent polymer catalyst (SPC) mercury control modules to sulfur impregnated activated carbon taking into account capital and operating cost, mercury removal efficiency, safety, and performance risk. The facility implemented Envitech’s recommendation for an Envitech SBC mercury control scrubber. A vessel constructed of fiber reinforced plastic (FRP) provides excellent corrosion resistance and low cost. An inlet heater duct with controls optimizes temperature for maximum performance. An internal duct with bottom outlet near grade direct connects to the existing stack. The vessel has extra capacity to double the number of SPC modules to meet the conservative inlet concentration if needed.

The equipment was commissioned in December, 2018. Inlet and outlet stack tests confirm greater than 96.4% removal and emissions less than 5% of the MACT limit for existing FB SSI. The Envitech SPC mercury control scrubber provides an economic, high performance, safe solution for continued incineration operation.  It can be applied to other types of applications that require mercury control downstream of wet scrubber equipment.  It provides a worthwhile technology to consider for mercury control.

Click on the link below to download a sewage sludge incinerator (SSI) mercury control scrubber case study and other SSI incinerator scrubbing literature.

 

Download Literature

Topics: Scrubbers, MACT Standards, Incinerator Scrubber

Ozone Injection for NOx Control on Medical Waste Incinerators

Posted by Andy Bartocci on Tue, Oct 30, 2018 @ 09:39 AM

Early this year I posted about achieving ultra-low emission limits for medical waste incinerator scrubbers.Med waste incinerator scrubber Front  An example was given for a captive incinerator at the University of Texas Medical Branch (UTMB) in Galveston, TX. It’s one of the only systems in the United States permitted as a “new” medical waste incinerator according to the EPA HMIWI (hospital, medical, and infectious waste incinerator) MACT standard. This standard has the most challenging emission limits found in industry today. That is because in 2009 the EPA completed a source review and revised the standard based on a MACT-on-MACT analysis.  Data used to set limits for each pollutant was individually based on waste feed and not incinerator/scrubber technology performance.  This resulted in emission limit reductions for lead (Pb), cadmium (Cd), and dioxins/furans (D/F) that were orders of magnitude below the previous standard and below the capability of installed equipment.  The impact of the new standard is discussed in greater detail in a 2013 blog post and corresponding paper from the Air & Waste Management Association (AWMA) International Conference on Thermal Treatment Technologies and Hazardous Waste Combustors (IT3/HWC)..
Medical waste incinerator Scrubber add-on controlsExisting incinerators needed to be upgraded with add-on controls to meet the new standard.  New incinerators need air pollution control equipment capable of extraordinarily high removal efficiency for particulate, Pb, Cd, and D/F.  A new medium sized incinerator between 200 to 500 lb/hr capacity, has the additional challenge of meeting NOx.  A medical waste incinerator can be tuned to a NOx limit of about 130 ppmv.  The MACT standard limit for a new medium sized medical waste incinerator was set at 67 ppmv which means NOx abatement is required to guarantee compliance.

Envitech is building two scrubber systems to treat exhaust gases from two new medical waste incinerators that will treat captive waste at a research facility.  The incinerators are permitted as new medium size incinerators which must meet the 67 ppmv NOx limit. The scrubbers have an equipment arrangement for meeting emission standards for PM, HCl, SO2, Pb, Cd, Hg, D/F, and opacity.  The schematic below shows the components of the gas cleaning system. The quencher is used to cool the gas to saturation and remove large particulate. The packed bed condenser/absorber sub-cools the gas and removes acid gases with caustic injection. The Venturi scrubber removes particulate and the majority of heavy metals. The gas then passes through additional polishing controls to meet the ultra-low emission limits for Pd, Cd, Hg, and D/F. The polishing equipment includes a re-heat duct followed by a filter and carbon bed adsorber.Med waste scrubber PFD

NOx removal is achieved by injecting ozone injection into the quencher outlet. The sizIMG_1032 Backside 1e of the condenser/absorber is increased to provide sufficient residence time for ozone-NOx reactions to occur.  Ozone is highly selective for NOx relative to other combustion products.   The NOx is rapidly converted to water soluble species. NO and O3 react to form NO2 and O2.  NO2 and O2 react to form N2O5 and O2. N2O5 and water react to form 2HNO3 which is readily absorbed with caustic solution.

Envitech used it’s rectangular scrubber design for the condenser absorber. To maintain a modular design and make it shippable.  The vessel was flanged connected and shipped in two pieces. The scrubber system otherwise looks like a typical medical waste incinerator scrubber except the condenser/absorber is double the height compared to systems that do not require NOx control.

The system has been built and shipped to the site. The major components are installed at the facility.  Envitech will deliver a water treatment system in 2019 to treat the scrubber effluent before it is discharged to the facilities main water treatment system.  System Start-up is scheduled for 2020.

Click on the link below to download a case study and other medical waste incinerator scrubbing literature.

 Download Literature

Topics: Scrubbers, Acid Gas, MACT Standards, Medical Waste Incinerator Scrubber, Incinerator Scrubber, NOx

Achieving Ultra-low Emission Limits for Medical Waste Incinerator Scrubbers

Posted by Andy Bartocci on Wed, May 16, 2018 @ 05:00 AM

Last March I gave a paper and presentation at the International Conference on Thermal Treatment Technologies and Hazardous Waste Combustors (IT3/HWC) in Houston, TX.  The paper discusses the challenges for meeting ultra-low emission limits for medical waste incinerators. 1102_UTMB_Scrubber_Skid Wet scrubbers are used to control hazardous air pollutants (HAPs) on many hospital, medical, and infectious waste incinerators (HMIWI).   The Maximum Available Control Technology (MACT) standard for these incinerators was revised and became final in 2009.  The new standard has the lowest emission limits for incinerators today. The limits exceeded the capability of systems designed to the previous standard with respect to particulate matter (PM), lead (Pd), cadmium (Cd), mercury (Hg), and dioxin/furans (D/F).  By 2014 all existing medical waste incinerators were either shut down or upgraded to comply with the new standard.  Envitech successfully upgraded four existing medical waste incinerators.  A paper presented at the 2012 IT3/HWC conference describes one of these systems which was installed at the National Institute of Health (NIH), Rocky Mountain Labs.

The challenge moving fo1102_General_Assembly_1rward will be new medical waste incinerators which have even more stringent, ultra-low emission limits.  Building a new incinerator requires critical decisions on control technologies and permitting.  The IT3/HWC paper reviews these issues for specific HAPs and discuss trade-offs between permitting a new medium size incinerator versus a large incinerator.   An example is provided of an air pollution control system meeting the emission requirements for a new large medical waste incinerator at the University of Texas Medical Branch (UTMB) in Galveston, TX.  Envitech is also building gas cleaning systems for two new medium size medical waste incinerators for a research facility which integrate NOx control using ozone injection.

 

Please click on the links below download the presentation and paper.

 Download Literature

Topics: Scrubbers, Medical Waste Incinerator Scrubber, Incinerator Scrubber, HMIWI Scrubber