Pet Coke vs Coal: What is Different?

In the global energy and industrial system, both coal and petroleum coke are important carbon-based raw materials. Coal has a long history and is an important raw material for energy supply. Petroleum coke is a by-product in the petroleum refining process, and its application has gradually expanded with the development in recent years. The two have similarities and differences in many aspects, and analyzing their differences is of great significance.

Basic Characteristics

Definition and Formation

Petroleum coke is the product obtained by thermal cracking of heavy oil after the distillation of crude oil to separate light and heavy oil. After the reaction is completed, petroleum coke eventually forms black blocks or granules, accompanied by the generation of by-products such as gas and light oil. According to the different properties of the raw oil and processing techniques, petroleum coke can be classified into types. And its quality is closely related to the sulfur content and heavy metal content of the petroleum raw materials.

Coal is a solid combustible mineral formed by complex biochemical and physicochemical changes in ancient plants. Influenced by factors such as sedimentary environment, pressure and temperature, it gradually transforms into different types of coal such as lignite, bituminous coal and anthracite.

Physical Properties

Appearance and Morphology

The appearance of petroleum coke is a black or dark gray honeycomb-like solid with metallic luster, which is usually in block or granular form. Coal has a variety of appearance colors, ranging from the brown of lignite to the black of anthracite. Its forms include block and powder, and bituminous coal often has distinct strip-like textures.

Density and Hardness

The density of petroleum coke is generally 1.3-1.9g/cm³, which has relatively high hardness and a hard texture. Due to different types, the density of coal varies greatly. For example, the density of lignite is approximately 0.9-1.2g/cm³, while that of anthracite can reach 1.4-1.9g/cm³. And its overall hardness is lower than that of petroleum coke, especially lignite which is relatively soft in texture.

Chemical Properties

Elemental Composition

Petroleum coke is mainly composed of carbon, with a content of 80% to 97%, which also contains small amounts of hydrogen, sulfur, nitrogen, oxygen and other elements. The sulfur content of high-sulfur petroleum coke can even reach over 5%. Although the elemental composition of coal is also mainly carbon, there are significant differences among different types of coal. Lignite has a carbon content of about 60% to 77%, while anthracite has a carbon content exceeding 90%, which also contains a certain amount of minerals.

Calorific Value and ash content

The calorific value of petroleum coke is relatively high, which rang generally from 28 to 35MJ/kg. And it has a relatively low ash content, usually less than 1%. The calorific value of coal fluctuates greatly, for example, the calorific value of lignite is approximately 10-20 MJ/kg, and that of anthracite can reach 25-35 MJ/kg. And its ash content is relatively high, generally ranging from 10% to 30%, and for some inferior coal is even higher.

Application Fields

Pet Coke

Energy Field

Industrial Heating

In terms of industrial heating, you can use petroleum coke as fuel for industrial boilers. It can provide thermal energy for industries such as steel and cement.

Fuel for Power Generation

In some regions, it is mixed and burned with coal for power generation to enhance the efficiency of power generation.

Metallurgical Industry

Electrode Production

In the production of electrodes, high-quality petroleum coke is a key raw material for manufacturing high-power and ultra-high-power graphite electrodes. With the excellent electrical conductivity and high-temperature resistance, it can meet the requirements for electrode usage.

Carbon Additive

You can use it in the steelmaking and casting processes to effectively increase the carbon content of steel and cast iron.

Chemical Industry

Raw Material Production

As a raw material for production, it is used to produce chemical products such as calcium carbide and silicon carbide.

Carbon Material Preparation

In the preparation of carbon materials, You can further process it to manufacture advanced carbon materials such as high-performance carbon fibers and carbon nanotubes.

Other Applications

Activated Carbon Manufacturing

Its well-developed pore structure endows activated carbon with excellent adsorption performance, so you can use it to manufacture activated carbon.

Fuel Additives

Using it as a fuel additive can improve the combustion performance of the fuel.

Coal

Energy Field

Thermal Power Generation

Coal plays an important role in thermal power generation and most of the world’s electricity is generated by coal-fired units.

Central Heating

It provides an important heat source for winter heating in northern regions, which is especially widely applied in small and medium-sized cities and rural areas.

Metallurgical Industry

Coke Production

As the core application of coal in the metallurgical industry, coking coal is processed into coke through high-temperature dry distillation and used in blast furnace ironmaking.

High-Furnace Injection

In this process, by injecting finely ground coal powder into the blast furnace to replace part of the coke, the production cost can be reduced.

Chemical Industry

Coal Chemicals

The coal chemical industry, including coal-to-methanol and coal-to-olefins, etc., is an important way for the clean and efficient utilization of coal.

Coal Tar Processing

Coal tar processing can produce a variety of chemical raw materials, such as benzene, toluene, phenols, etc.

Other Applications

Building Materials Production

You can use coal to burn cement, lime, etc. Its ash and slag can be used as raw materials or filling materials to help improve the performance and output of building materials.

New Carbon Materials

Through technological innovation, it can also be used to prepare new types of carbon materials, such as graphene.

Environmental Impact

Carbon Emissions

The combustion of petroleum coke and coal both produce a large amount of carbon dioxide, which are important carbon emission sources causing global warming. But due to the high carbon content of petroleum coke, the amount of carbon dioxide produced per unit mass of combustion is even higher.

Pollutants

The combustion of petroleum coke generates pollutants such as sulfur dioxide, nitrogen oxides and particulate matter. In addition to generating the above-mentioned pollutants, coal combustion also releases a large amount of heavy metal pollutants. So it will cause pollution to the atmosphere, soil and water.

Market and Economic Analysis

Market Supply and Demand

The supply and demand of the coal market are influenced by factors such as the global economic situation and energy policies. Although the growth rate of coal demand has slowed down, there is still considerable demand in developing countries. The supply and demand of the petroleum coke market are closely related to the scale of petroleum refining. Because of the expansion of the petrochemical industry, the output of petroleum coke has been continuously increasing. And the market competition of it has also become increasingly fierce.

Price Fluctuations

The price of coal is influenced by factors such as origin, quality, transportation costs and policy regulation, and fluctuates greatly. While the price of petroleum coke is closely related to the price of petroleum and the relationship between supply and demand. If the price of petroleum drops, the price of petroleum coke often decreases accordingly.

Conclusion

Petroleum coke and coal have similarities and differences in many aspects and are both important raw materials for energy and industry. Under the background of “dual carbon”, it is necessary to promote transformation and upgrading respectively. And providing better support for the development of energy and industry through innovation.