. At 5 C, 17 target VOCs were found, and at 40 C, 20 target VOCs were detected, with five VOCs accounting for almost all (9596%) of TTVOC at each temperature: toluene (25 28%), benzene (1920%), n-heptane (1820%), cyclohexane (17 18%), and methyl cyclohexane (17 18%). (1112 percent ). TTVOC concentrations were from 16.1 g m3 at 5 degrees Celsius to 63.9 g m3 at 40 degrees Celsius. The vapour proportion of several of the most common VOCs in the liquid fuel (e.g., p-, m-xylene, and 1,2,4-trimethylbenzene) was low, and high volatility compounds dominated the headspace vapour.
What are some VOC examples?
VOCs (volatile organic compounds) are a class of chemicals found in many of the goods we use to construct and maintain our homes. Once in our houses, these chemicals are discharged or “off-gas” into the air we breathe. They may or may not be odorable, and odour is not a reliable signal of health risk.
Benzene, ethylene glycol, formaldehyde, methylene chloride, tetrachloroethylene, toluene, xylene, and 1,3-butadiene are examples of VOCs that may be present in our daily life.
Is gasoline flammable?
Gasoline is a mixture of relatively volatile hydrocarbons with a wide range of physical and chemical properties, including regular and branched chain alkanes, cycloalkanes, alkenes, and aromatics. Alkanes, aromatics, and alkenes are commonly found in liquid gasoline (IARC 1989).
Is gasoline oil a volatile organic compound (VOC)?
Fuel oils are mostly used in marine and power plant applications. They are known to contain harmful volatile organic compounds (VOCs) that are harmful to human health and the environment. Some of the VOCs that have found their way into fuel oil through various streams during bunkering operations include chlorinated compounds, phenolic compounds, styrenes, indene, dicyclopentadiene, dihydrodicyclopentadiene, cumene, benzene, toluene, ethylbenzene, and xylenes. One of the key obstacles in dealing with goods of this sort is chromatographic examination of VOCs in the presence of complex matrices in fuel oil. For the measurement of these chemicals in fuel oil, an analytical approach based on automated static headspace gas chromatographymass spectrometry was developed. Internal standards for quantification were styrene D8 and phenol D6. For the quantification of phenolic compounds, phenol D6 was utilised, while styrene D8 was employed for the quantification of other target analytes. Temperature, incubation period, and sample amount were all evaluated and optimised as headspace parameters on analyte response. All components had linear calibration curves with R2 > 0.995 determination coefficients. There were reports on repeatability, limit of detection, limit of quantitation, and recovery. The matrix impact in fuel oil was reduced to a minimum by diluting it 1:1 with mineral oil. Commercial samples were successfully analysed using this technology.
What does not qualify as a VOC?
Any carbon compound that participates in atmospheric photochemical reactions, excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates, and ammonium carbonate, is referred to as a volatile organic compound (VOC), with the exception of those designated by the Environmental Protection Agency as having negligible photochemical reactivity2.
Volatile organic compounds, or VOCs, are organic chemical molecules with a composition that allows them to evaporate at standard indoor temperature and pressure conditions3. This is the scientific literature’s broad definition of VOCs, which is similar to the definition used for indoor air quality. Because a compound’s volatility4 increases as its boiling point temperature decreases, the volatility of organic compounds is commonly characterised and categorised by their boiling points.
The European Union, for example, defines VOCs based on their boiling point rather than their volatility.
Any organic compound with an initial boiling point of less than or equal to 250 C measured at 101.3 kPa is classified as a VOC.
5, 6, and 7
VOCs are frequently classified according to how easily they can be emitted. Indoor organic pollutants, for example, are classified by the World Health Organization (WHO) as follows:
- Organic molecules that are extremely volatile (VVOCs)
- Organic substances that are volatile (VOCs)
- Organic molecules that are semi-volatile (SVOCs)
The lower the boiling point of a substance, the more probable it is to be discharged into the air from a product or surface. Very volatile organic compounds are difficult to quantify because they exist almost exclusively as gases in the air, rather than in solids or on surfaces. The least volatile compounds found in air make up a small percentage of the total present indoors, with the majority being contained in solids or liquids containing them, or on surfaces such as dust, furnishings, and building materials.
Is ethanol a volatile organic compound (VOC)?
Volatile organic compounds (VOCs) are organic chemical compounds with a high vapour pressure and a low boiling point that can quickly evaporate into the air. Ethanol, formaldehyde, benzene, toluene, and xylene are examples of common VOCs. Indoor and outdoor air quality are both affected by VOCs. Indoor VOCs are typically emitted from consumer products and construction materials like paints and carpets, and they can have a negative impact on people’s health. Outdoor VOCs are typically released by industrial sites and cars, and they can contribute to photochemical smog production. Many countries have passed laws restricting the use of VOCs in consumer goods. In this post, we will review various definitions of VOC and provide an overview of VOC content restrictions for consumer products in the United States, Canada, and the European Union.
Definitions of VOCs – Similar But Different
Depending on whether the VOCs are indoor VOCs or outdoor VOCs, each jurisdiction or country may have distinct official definitions for VOCs. Typically, there isn’t a comprehensive list of VOCs. However, because to their low concern, some volatile organic compounds may be removed from the classification of VOCs.
- Indoor VOCs are organic chemical compounds with a composition that allows them to evaporate under normal indoor temperature and pressure conditions.
- Outdoor VOCs: Any carbon compound that participates in air photochemical reactions, excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates, and ammonium carbonate, save those recognised by the EPA as having low photochemical reactivity.
- Any non-excluded volatile organic molecules that engage in photochemical reactions in the atmosphere.
- Any organic compound whose initial boiling point is less than or equal to 250C when measured at 101,3 kPa;
- Non-methane hydrocarbons (alkanes, alkenes, alkynes, aromatic hydrocarbons, and so on), oxygenated organic compounds (aldehydes, ketones, alcohols, ethers, and so on), chlorine-containing organic compounds, nitrogen-containing organic compounds, sulfur-containing organic compounds, and so on are all examples of volatile organic compounds that participate in atmospheric photochemical reactions.
- VOCs are gaseous organic molecules that are released into the atmosphere. By government regulation, substances (methane and hydrochlorofluorocarbon) that do not create suspended particulate matter or oxidants are excluded.
VOC Regulations for Consumer Products in USA
The US Environmental Protection Agency (EPA) has issued National Volatile Organic Compound Emission Standards for Consumer Products, which set VOC limits for a variety of consumer products (see picture below). Furthermore, many states (such as California) have drafted their own VOC content guidelines for consumer products, which are sometimes stricter than the EPA’s.
- National Volatile Organic Compound Emission Standards for Consumer Products – United States Environmental Protection Agency
- VOC Limitations for Institutional and Consumer Products – State and Federal – ISSA
VOC Regulations for Consumer Products in Canada
In 2013, Environment Canada released a revised version of the proposed Volatile Organic Compound (VOC) Concentration Limits for Certain Products Regulations. The proposed legislation would set VOC level limitations for 98 categories of products, including personal care products, household maintenance products, adhesives, coatings, and automobile refinishing materials, if it were to go into effect. The recommended VOC limits are designed to be as similar as practicable to those set by the California Air Resources Board (CARB) and the US Environmental Protection Agency (EPA).
- The Proposed Volatile Organic Compound (VOC) Concentration Limits for Certain Products Regulations – 2013 have been revised.
VOC Regulations for Consumer Products in EU
The maximum amounts of VOCs (in g/L) in paints, varnishes, and vehicle refinishing goods are defined by EU Directive 2004/42/EC on the control of emissions of volatile organic compounds owing to the use of organic solvents in decorative paints and varnishes and vehicle refinishing products. Suppliers must also mark the product’s subcategory, the legal limit value for VOC contents, and the maximum VOC content of the product in its ready-to-use condition, according to the directive.
The VOC concentration restrictions for several paints are shown in the diagram below:
- Directive 2004/42/CE of the European Parliament and of the Council of 21 April 2004 on the limitation of emissions of volatile organic compounds due to the use of organic solvents in certain paints and varnishes and vehicle refinishing products and amending 1999/13/EC Directive
Is propane a volatile organic compound (VOC)?
Organic chemical substances that are gaseous or can vaporise and enter the atmosphere under normal conditions. Methane, benzene, xylene, propane, and butane are examples of VOCs.
What makes gasoline so flammable?
Gasoline is made up of a number of distinct components that evaporate at various temperatures. The components that vaporise quickly evaporate at lower temperatures than those that vaporise slowly. Gasoline volatility regulations have been developed in Michigan (ability to vaporize).
What causes gasoline to be so volatile?
When the available supply of gasoline falls short of real or predicted demand or consumption, gasoline prices tend to rise. If crude oil supplies, refinery operations, or gasoline pipeline deliveries are disrupted, gasoline prices can change quickly. Gasoline prices fluctuate even when crude oil prices are steady due to seasonal changes in demand and gasoline specifications.
Crude oil and gasoline prices reached record levels in 2008
As a result of increasing global oil demand versus supply, international crude oil prices hit new highs in 2008. Significant increases in demand in China, the Middle East, and Latin America, combined with global supply market uncertainty, contributed to the rise in oil prices and, as a result, to record-high gasoline prices in the United States.
Seasonal demand and specifications for gasoline
Retail gasoline prices have historically risen steadily in the spring and peaked in late summer, when consumers drive more frequently. In general, gasoline costs are lower during the winter months. Seasonal variations in gasoline standards and formulas can also be found. In order to comply with environmental standards, gasoline marketed in the summer must be less prone to evaporation in hot weather. As a result of this rule, refiners must substitute less evaporative but more expensive gasoline components for cheaper but more evaporative components. From 2000 to 2020, the average monthly price of regular-grade gasoline in the United States was nearly 32 cents per gallon higher in August than in January.
What is the composition of gasoline?
Gasoline is a petroleum-based fuel manufactured from crude oil and other liquids. Gasoline is mostly utilised in vehicles as an engine fuel. Motor gasoline is produced in petroleum refineries and blending facilities for sale at retail gasoline filling stations.
The majority of gasoline produced by petroleum refineries is unfinished gasoline (or gasoline blendstocks). To manufacture finished motor gasoline, gasoline blendstocks must be blended with other liquids to meet the basic standards for fuel acceptable for use in spark ignition engines.
Some finished motor gasoline is produced by petroleum refineries in the United States. Most finished motor gasoline sold in the United States, on the other hand, is made at blending terminals, where gasoline blendstocks, finished gasoline, and fuel ethanol are blended to make finished motor gasoline in various grades and formulas for consumer use. Detergents and other additives are sometimes combined into gasoline before it is delivered to retail outlets by some corporations.
Blending terminals are more numerous and widely distributed than petroleum refineries, and they feature filling stations for tanker trucks that transport finished motor gasoline to retail outlets.
The majority of finished motor gasoline marketed in the United States today contains roughly 10% fuel ethanol by volume. Ethanol is added to gasoline primarily to comply with the Renewable Fuel Standard, which aims to reduce glasshouse gas emissions and the amount of oil imported from other nations by the United States.
Is methane a volatile organic compound (VOC)?
Do you ever wonder what some of your environmental department’s truncated technical words mean?
Do you work in the oil and gas business or in the storage of crude oil?
If you answered yes, you should be familiar with the ABCs of VOCs.
VOC emissions are classified as organic molecules that participate in atmospheric photochemical processes, according to USEPA regulations.
40 CFR 51.100 contains the definition of VOCs (s).
A list of substances that aren’t classified as VOCs is included in the definition.
Methane and ethane are two chemical molecules that are not categorised as VOCs.
Photochemically reactive VOCs are controlled because, in the presence of sunlight, they chemically react with oxides of nitrogen (NOx, a consequence of fossil fuel combustion) to generate ozone (O3) in the troposphere (lowest portion of the earth’s atmosphere).
VOCs are contaminants in the air that contribute to the development of ozone.
The management of VOCs is intended to avoid the release of one of the precursors to ozone production into the atmosphere.
Smog contains a lot of ozone, which is a potent oxidant.
Long-term exposure to ozone levels exceeding 75 parts per billion (ppb) can harm people’ mucous and respiratory tissues, as well as plants.
As a result, ozone is a significant human respiratory threat at ground level.
It’s worth noting that the earth’s so-called Ozone Layer (a part of the stratosphere with a greater ozone content) is advantageous to life on the planet.
This ozone layer in the stratosphere serves to keep harmful ultraviolet (UV) rays from reaching the Earth’s surface.
It’s crucial to remember that VOCs don’t include methane (CH4), ethane (C2H6), H2S, CO2, or N2 for the oil and gas industry to comply with the alphabet soup of air quality laws.
When determining the mass of VOCs in a vented natural gas stream, use the propane plus hydrocarbon (C3+) fraction in the natural gas as a starting point.
Of fact, because of the reporting requirements for glasshouse gases, methane in the natural gas stream is still significant.
This is crucial for air permits and NSPS OOOO/OOOOa compliance because venting from sources like storage tanks simply has to account for the VOC proportion in the gas.
Another factor to keep in mind is that the VOC level of storage tank vent gas is often substantially higher than that of HP separator gas.
VOC content in a storage tank vent may range from 35 percent to 50 percent by volume, whereas VOC content in an HP separator gas typically ranges from 80 percent to 98 percent by volume.
As a result, the mass (pounds) of VOC emissions from a volume of storage tank vent gas will be larger than the same volume of HP separator gas.
Natural gas can contain the following components:
- C10+ plus decane plus decane plus decane plus decane plus decane
- 2,2,4-trimethylpentane
The ideal gas law is used to compute the mass of natural gas and the concentration of volatile organic compounds (VOCs). We use the formula that one pound mole (lb-mole) of a gas occupies approximately 379.3 standard cubic feet at standard circumstances (60F, 14.7 psia) (SCF). The molecular weight of the gas stream or natural gas component is represented by the lb-mole.
This gas stream would emit over 731 tonnes of VOC per year if it were vented to the atmosphere at a rate of 500,000 SCF per day.
Sources of VOC emissions in the oil and gas industry include:
- Tanks for storage Crude oil, condensate, and produced water are all examples of petroleum products.
- Process/Emergency Vents
- Pneumatic Pumps Powered by Natural Gas (e.g., Wilden/Aro/Texsteam)
- Still Column & Flash Tank Glycol Dehydrators
- Compressor Seals (Reciprocating and Centrifugal)
- Pneumatic devices for natural gas (e.g., pressure/level controllers)
- Tank trucks and barges are examples of loading/unloading facilities.
- Sweetening Units for Amine Gas
- Dump Valves That Are Stuck
- Unloading of Well Liquids and Well Venting
- Equipment Leaks Cause Fugitive Emissions
- Stacks for Blowdown Ventilation at a Facility
- Hydrocarbons Unburned from Engine Exhaust and Flares
- Gas Venting at the Well Casing Head
Many people believe that in the future, federal and state regulations on VOC emissions will get harsher and include more processes in the oil and gas industry. The following are some examples:
- Collect data on current oil and gas production sites and emissions (prior to August 24, 2011). This includes facilities that aren’t affected by the NSPS OOOO and OOOOa.
- Existing sites not affected by NSPS OOOO and OOOOa emission limits.
- Methane emissions from oil and gas operations should be regulated.
- Reporting of glasshouse gases (GHG) from more facilities than the GHG reporting standards in 40 CFR Part 98 currently demand.
Capturing these vent gas streams and delivering the gas to sales, where possible, can help a facility enhance production and revenues.
