At GCES so much of our job focus is on VOCs. Over the years we have come to realize that VOCs and the treatment of them is very misunderstood. Our Technical Director, Chad Clark, has spent much of his career as a Mechanical Engineer dedicated to the advancement of VOC abatement. Having developed cutting edge technology and BACT improvements he is a true subject matter expert and has provided the following to help improve the understanding of VOCs and how to best abate them through the use of pollution control equipment.
What are VOCs?
Organic Compounds (hydrocarbons) are naturally occurring substances that can be found in all living things. However, the solvents being emitted from manufacturing processes are considered Volatile Organic Compounds. The hydrocarbons are considered “unstable” or “volatile” since they produce a vapor at room temperature and normal atmospheric pressure.
The Environmental Protection Agency classifies Volatile Organic Compounds (VOCs) to mean “any compound of carbon, excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates, and ammonium carbonate, which participates in atmospheric photochemical reactions.”
A good example of seeing a volatile organic compound would be when you witness the fumes leaving a gas pump as you fill up your car.
Why do we need to abate/treat VOCs
VOCs are contributors to the formation of ozone and smog. Extremely low levels of Ozone can cause significant respiratory difficulties in a sizable portion of the population and also contributes to the photochemical formation of Smog. Smog is the hazy brown cloud hovering over the major cities of the world which destroys agriculture and forests and damages our entire environment. Many of these cities, both domestically and internationally, have dedicated resources to combating smog that we are proud to be partnered with.
The mechanism for ozone production is: VOC + NOx + sunlight (UV) = Ozone
NOx is a term used to describe various oxides of nitrogen compounds, such as Nitrous Oxide, Nitrous Dioxide, etc. NOx originates from high temperature combustion sources such as automobiles, utility power plants, boilers, combustion engines, etc. The charts below show the sources of emissions in the east Texas and western Louisiana region.
How do we control VOCs?
A VOC Abatement System relies upon the concept of a chemical reaction – when involving organic hydrocarbons the process is called oxidation. In an oxidation process, the compounds within the air stream – VOC pollutants – are broken down from their original composition and reformed into new (in this case safe) compounds. In the VOC Oxidation Process, enough heat and oxygen are added to the hydrocarbons to create the oxidation reaction – this process is called Thermal Oxidation.
By breaking the original composition of the VOC Hydrocarbons – carbon and hydrogen – we allow the two constituents to reform naturally into carbon dioxide and water vapor while releasing heat energy. The heat energy is then recuperated into the system by use of a heat exchange device, while the now clean air stream of carbon dioxide and water is discharged to atmosphere.
nO2 + CnH2n = nCO2 + nH2O + Heat
Oxygen + Hydrocarbons = Oxidation
At GCES we have custom designed, manufactured and installed thousands of VOC treatment solutions that currently operate in nearly 100 countries. Offering a full range of Thermal Oxidizers including RTO’s, TO’s, TRO’s, CATOX, Catalytic Thermal Oxidizers, DFTO’s and the breakthrough Aqueous RTO we are your one stop shop for all your pollution control system needs. In addition GCES provides the following air pollution control systems:
- Vapor Combustion Units
- Concentrators
- Emission Concentrators
- Rotor Concentrators
- VOC Concentrators
- Flares
- Scrubbers
- NOx Abatement Systems
- Carbon Adsorbers
For more information on air quality and EPA data visit https://www3.epa.gov/airdata/. To learn more about how we can help with your pollution control needs contact us at 832.476.9024 or sales@gcesystems.com.
Additional articles in the GCES series ‘Abating Hazardous Air Pollutants’ include:
- Part 1: BTEX is an acronym that stands for Benzene, Toluene, Ethylbenzene and Xylenes.
- Part 2: Chlorine Abatement
- Part 3: NOx is the family of air polluting chemical compounds, Nitrogen Oxides.
- Part 4: Lead is also known (incorrectly) as mercury because they are often found together
- Part 5: Industrial air scrubbers for the treatment of ammonia
- Part 6: SOx, the compounds of sulfur and oxygen molecules including Sulfur Monoxide, Sulfur Dioxide and Sulfur Trioxide
- Part 7: Hydrocarbons – Methane, Ethane, Propane, Butane, Pentane, Hexane
- Part 8: Methyl Mercaptan – Methyl Mercaptan, also known as Methanethiol
- Part 9: H2S – Highly corrosive Hydrogen Sulfide
- Part 10: Dimethyl Sulfide – Methylthiomethane
- Part 11: Sulfuric Acid – H2SO4
- Part 12: Ethylene Oxide – EtO