Typically, boiler models are differentiated by what fuel is used to power them. It’s important to pay attention to the type of fuel your boiler needs, as it often has a significant impact on your operating costs. It can also have an impact on your environmental impact, so familiarity with all the various types of boiler fuels is essential.
Fuel cost is the most important cost in boiler operation cost, and boiler operation cost with different fuels is also different. Especially at the beginning of boiler selection, it is most important to choose the most suitable type of boiler for fuel. So, what fuel has the lowest operating cost for a boiler?
What is a Boiler Fuel?
The so-called fuel is a substance that releases a lot of heat energy when it is burned and can be effectively used. The fuel used in boiler combustion can be divided into solid fuel, liquid fuel, gas fuel and other four types according to their different physical states.
The primary steam boiler fuels are coal, oil, and gas. Oil and gas involve the simplest controls since they can be measured easily and flow is regulated by a control valve in the fuel line.
Most Common Types of Boiler Fuels
Boilers can use a variety of fuels to generate steam or hot water for heating, industrial processes, or power generation. The choice of fuel depends on factors such as availability, cost, efficiency, and environmental considerations. Here are some common types of boiler fuels:
1. Natural Gas: Natural gas is a widely used fuel for boilers due to its availability, relatively low cost, and cleaner combustion compared to other fossil fuels. It is commonly used in residential, commercial, and industrial applications.
2. Oil (Fuel Oil): Various grades of oil, such as No. 2 (diesel), No. 4, and No. 6 fuel oils, can be used in boilers. These oils are commonly used in industrial applications and in places where natural gas is not readily available.
3. Coal: Although coal has become less popular in many areas due to environmental concerns, some boilers still use coal as a fuel source. Different types of coal, including anthracite, bituminous, and sub-bituminous, have varying combustion characteristics.
4. Biomass: Biomass fuels, such as wood pellets, wood chips, agricultural residues, and other organic materials, can be used in boilers. Biomass is considered a renewable and carbon-neutral energy source, making it an environmentally friendly option.
5. Electricity: Electric boilers use electricity as the primary source of energy. They are common in areas where electricity is abundant and relatively inexpensive. Electric boilers are often used in residential and small-scale industrial applications.
6. Propane: Propane is a liquefied petroleum gas (LPG) and is commonly used as a boiler fuel in areas where natural gas is not readily available. It is often used in residential and small commercial applications.
7. Hydrogen: Hydrogen is an emerging clean fuel that can be used in boilers to produce heat. It is considered a promising option for reducing carbon emissions when produced using renewable energy sources.
8. Waste Heat: Some industrial processes generate waste heat, which can be captured and used as a boiler fuel. This is common in industries such as power generation, chemical manufacturing, and refining.
9. Dual-Fuel: Some boilers are designed to burn more than one type of fuel. For example, a dual-fuel boiler might be capable of using both natural gas and oil, allowing flexibility in fuel choice based on availability and cost.
The choice of boiler fuel depends on various factors, including regional fuel availability, cost considerations, efficiency requirements, and environmental regulations. Additionally, the growing focus on sustainability is driving the exploration of alternative and cleaner fuels for boiler systems.
Examining Cost Factors for Different Fuels in Industrial Boilers
Photo by Proquimia
Let’s break down the costs associated with various fuels for a 1-ton boiler operating at full load:
1. Natural Gas
– Market rate: 4.2 yuan/m3
– Consumption: 82m3/h
– Cost calculation: 82m3/h × 4.2 yuan/m3 = 344 yuan
– Daily operation (8 hours): 344 yuan/h × 8 h = 2752 yuan
2. Coal
– Market price: 950 yuan/ton
– Consumption: 170 kg/h
– Cost calculation: 170 kg/h × 950 yuan/ton = 160 yuan/h
– Daily operation (8 hours): 160 yuan/h × 8 h = 1280 yuan
3. Heavy Oil
– Price: 4.8 yuan/kg
– Consumption: 82 kg/h
– Cost calculation: 82 kg/h × 4.8 yuan/kg = 394 yuan/h
– Daily operation (8 hours): 394 yuan/h × 8 h = 3152 yuan
4. Light Diesel
– Price: 8.1 yuan/kg
– Consumption: 69 kg/h
– Cost calculation: 69 kg/h × 8.1 yuan/kg = 559 yuan/h
– Daily operation (8 hours): 559 yuan/h × 8 h = 4472 yuan
5. Industrial Electricity
– Price: 1.1 yuan/kWh
– Consumption: 727 kWh/h
– Cost calculation: 727 kWh/h × 1.1 yuan/kWh = 800 yuan/h
– Daily operation (8 hours): 800 yuan/h × 8 h = 6400 yuan
After a thorough comparison, coal-fired boilers emerge with the lowest cost. However, it’s crucial to note that the lowest cost doesn’t automatically make coal-fired boilers the ideal choice, as other factors need consideration.
Navigating Key Considerations for Boiler Fuel Selection
Selecting the appropriate boiler fuel is a nuanced decision that goes beyond a mere examination of costs; it involves a comprehensive evaluation of three essential factors.
The first factor revolves around the cost of the boiler fuel. Are there substantial differences in the costs among various fuel types? Is it practical to consider lower-quality or less stable fuels?
The second factor delves into ease of use and security, posing questions about anticipated maintenance requirements over the boiler’s life cycle.
The third consideration explores the longevity of the boiler with a specific fuel type, comparing the lifespan of a boiler operating on one fuel to that using a different fuel type. Moreover, emissions produced by the boiler emerge as a critical factor that cannot be underestimated.
Precautions for Navigating Boiler Fuel Selection
1. Fuel Availability
Ensure that the chosen fuel is readily available near the plant site. Areas close to coal belt users commonly favour coal as a fuel, while regions with accessible agricultural waste may opt for the same. For example, rice mills might utilize rice husks as fuel. In economically viable areas for oil or gas, such as OPEC countries, these options are considered. Availability of natural gas should be considered if feasible.
2. Alternative Fuels
Consider the versatility of a boiler that can utilize multiple fuels from the same family, providing an added layer of flexibility.
3. Fuel Cost
Recognize the critical importance of fuel cost in the decision-making process. Achieving operational efficiency and economic benefits relies on selecting the appropriate fuel.
4. Pollution Control Regulations
Take into account the pollution control regulations in your region/state/country when choosing a fuel type. Natural gas and oil may be preferred if there are emission restrictions within city limits or specific SEZs.
In specific sectors/regions, pollution regulations may prohibit the use of solid fuels like coal or agricultural waste. Despite being more expensive, oil or natural gas may be the preferred fuel in such cases.