What is the Gross Calorific Values (GCV) of pyrolysis oil?

Pyrolysis oil, a valuable product derived from the thermal decomposition of organic waste materials such as used tires, plastics, and biomass, has gained significant attention in recent years due to its potential as a renewable energy source and feedstock for various industries. One of the key parameters that determine its utility and economic viability is its Gross Calorific Value (GCV), also known as the higher heating value (HHV).

Pyrolysis oil gross calorific value

The Gross Calorific Value (GCV) or Higher Heating Value (HHV) of pyrolysis oil derived from different feedstocks, such as plastics and tires, can vary based on the specific composition of the pyrolysis materials being processed. Here are the typical GCV ranges for pyrolysis oil derived from different feedstocks:

It's important to note that these calorific values of pyrolysis oils are approximate and can be influenced by a number of factors, which we will discuss below:

1. Feedstock Composition

The chemical composition of the feedstock for pyrolysis machine is one of the most significant factors affecting the GCV of pyrolysis oil. Feedstocks rich in carbon and hydrogen, such as used tires and plastic waste, tend to produce pyrolysis oil with higher GCV values.

Used Tires: Tires are primarily composed of natural and synthetic rubbers, which are rich in carbon and hydrogen. This results in pyrolysis oil with a high GCV, making it an excellent alternative fuel source.

Waste rubber tire materials for pyrolysis into fuel oil

Plastic Waste: Plastics like polyethylene (PE) and polypropylene (PP) are hydrocarbon-based and yield pyrolysis oil with relatively high GCV. On the other hand, plastics containing chlorine, such as polyvinyl chloride (PVA) and Polyethylene terephthalate (PET), can produce pyrolysis oil with lower GCV and potential environmental concerns due to the release of harmful gases during combustion. It's not suggested to use PVC and PET as the pyrolysis raw materials.

Plastic waste pyrolysis oil yields

Biomass: Biomass feedstocks, while renewable, contain a higher proportion of oxygen and moisture, which results in lower GCV values compared to tire and plastic-derived pyrolysis oils.

2. Pyrolysis Process Conditions:

The temperature and heating rate during pyrolysis significantly impact the GCV of the resulting oil. Higher pyrolysis temperatures and faster heating rates often lead to the production of a more energy-dense bio-oil. However, these conditions can also increase the production of light gases and reduce the liquid yield, which may lower the overall energy content of the oil.

Waste pyrolysis reactor with different heating ways

3. Moisture Content:

Pyrolysis oils often contain high amounts of water, which can dilute the calorific value. The moisture content in bio-oil can range from 20% to 30%, and it has a negative effect on the GCV. Oils with lower moisture content generally have a higher calorific value, making them more suitable for combustion or as fuel.

4. Chemical Composition:

The specific chemical composition of the pyrolysis oil plays a crucial role in determining its GCV. Oils rich in aromatic hydrocarbons tend to have a higher calorific value compared to those dominated by oxygenated compounds such as acids and aldehydes. The presence of these oxygenated compounds reduces the energy density because oxygen does not contribute to the calorific value in the same way as carbon and hydrogen.

Pyrolysis Oil Applications

Generally, pyrolysis oil with medium to high GCV can be used as direct fuel for industrial heating, such as industrial boilers, cement, brick factories and steel industries, which are energy-intensive industries, or used in heavy oil power plants for power generation. In addition, pyrolysis oil can be further refined into diesel through waste oil distillation equipment for use in diesel generators, tires, tractors, trucks and other heavy machinery. For precise measurement and application-specific suitability, conducting tests on the produced pyrolysis oil using standardized methods is recommended. This ensures accurate data relevant to the particular batch and intended use of the product.

Pyrolysis oil industrial applications

Therefore, the Gross Calorific Value (GCV) of pyrolysis oil is high and has wide applications as industrial heating fuel. But the actual heating values of pyrolysis oil can fluctuate based on raw materials and specific processing conditions. To get more technical details and waste treatment solutions about pyrolysis, please contact Henan Doing Company, one of the world-leading pyrolysis machine manufacturers and suppliers.