Dual-Fuel Generator Set: Efficient Power Generation Solution

The biogas-diesel dual-fuel generator set is a power generation device that utilizes a modified diesel engine's intake mixing system and dual-fuel regulation system to operate on both biogas and diesel. This unique working method allows the combined use of biogas and diesel, ensuring stable operation while effectively reducing diesel consumption and enhancing fuel efficiency. The generator set is suitable for small-scale biogas projects and demonstrates strong adaptability in situations with unstable energy supply. This article will detail the working principle, operational steps, and usage precautions for dual-fuel generator sets.

Working Principle

The core principle of the dual-fuel generator set is to mix biogas with air in a mixer, creating a combustible gas mixture that is then drawn into the cylinder. As the piston approaches the top of its stroke, a small amount of diesel is injected into the combustion chamber. The ignition of the diesel ignites the gas mixture in the cylinder, allowing combustion to occur. During operation, biogas serves as the main fuel, while diesel acts solely as the ignition source. Typically, the amount of diesel used for ignition is controlled between 8% and 20% of the diesel consumption before modification (calculated as the ratio of the igniting diesel amount to the rated diesel consumption of the unmodified engine). This ignition method takes advantage of diesel’s high ignition energy, reducing the ignition lag of biogas, improving combustion efficiency, and avoiding common issues like post-combustion in biogas engines. It also minimizes the risks of high exhaust temperatures and excessive thermal loads.

Operational Steps

When operating the dual-fuel generator set, please follow these steps.

1. Start the Diesel Engine

First, close the biogas valve and start the generator set using the traditional diesel engine startup method. Use diesel for the initial start. After starting, gradually increase the load and adjust the throttle to an appropriate position, typically slightly below mid-range, to ensure stable operation.

2. Introduce Biogas

Once the generator set is running smoothly, slowly open the biogas valve to begin introducing biogas into the cylinder. During this process, the governor will automatically reduce the diesel supply, keeping the engine speed stable. If too much biogas is introduced, fuel supply may be momentarily interrupted, causing the generator set to produce intermittent noise. In this case, reduce the biogas valve opening until normal operation is restored.

3. Adjust Engine Speed

Adjusting the engine speed is similar to a conventional diesel engine, achieved by changing the position of the throttle handle. When shutting down, close the biogas valve first, then close the throttle to ensure safe shutdown of the generator set.

Operational Precautions

When using a biogas-diesel dual-fuel generator set, operators should pay special attention to the following precautions to ensure safe and efficient operation.

1. Check Sealing

Regularly check the biogas valve, gas pipelines, and joints to ensure there are no leaks. Gas leaks can lead to serious incidents, such as fire or explosion, making regular inspection and maintenance of these components crucial.

2. Operate Biogas Valve Smoothly

When operating the biogas valve, do so gently to avoid rapid or violent adjustments. This helps prevent significant fluctuations in biogas input, which can lead to abnormal operation or instability in the generator set.

3. Monitor Load and Biogas Pressure

During operation, operators should continually monitor changes in load and biogas pressure. Experienced operators can increase fuel savings to 80%–90% under stable loads, while improper operation may limit savings to 50%–60%. Close attention to the generator set's operational status helps optimize the use of biogas and diesel, enhancing fuel efficiency.

4. Responding to Insufficient Biogas Supply

In the event of insufficient biogas supply, there is no need to shut down the generator set. Simply close the biogas valve halfway, and the generator can continue to operate like a regular diesel engine. This feature greatly enhances the reliability and adaptability of the dual-fuel generator set, allowing it to function normally even when biogas supply is unstable.

Advantages and Applications

The biogas-diesel dual-fuel generator set shows significant advantages in modern energy fields, effectively reducing costs while providing outstanding operational flexibility and a wide range of applications.

1. Efficient Use of Local Resources and Cost Reduction

The primary advantage of the biogas-diesel dual-fuel generator set is its ability to effectively utilize local biogas resources. By using biogas as the main fuel, diesel consumption is significantly reduced, leading to noticeable cost savings, especially for small biogas projects. This feature not only decreases reliance on traditional fossil fuels but also promotes the use of renewable energy.

2. Flexible Switching for Reliable Operation

When biogas supply is inadequate, the generator set can switch to diesel mode, even relying entirely on diesel combustion, ensuring stable operation. This flexibility allows it to perform well in environments with unstable biogas supply, guaranteeing continuous power generation and adapting to changing gas supply conditions.

3. Wide Applications in Rural and Small Industrial Settings

Dual-fuel generator sets are widely used in rural areas, agricultural production, and small industrial settings, particularly in regions rich in biogas resources but with unstable supply. They can efficiently generate power in small rural biogas projects while meeting the energy needs of agriculture and small industrial operations.

4. Easy Modification and Broad Promotion Prospects

Any four-stroke diesel engine can be easily modified without replacing major components to upgrade to a biogas-diesel dual-fuel generator set. This makes it convenient for technology promotion, offering good economic and environmental benefits, especially in areas and projects requiring low-cost, high-efficiency power generation.

Through these characteristics, biogas-diesel dual-fuel generator sets demonstrate significant advantages in resource utilization, operational reliability, application scenarios, and technology promotion.

Conclusion

The biogas-diesel dual-fuel generator set is an economical and flexible power generation device. By utilizing the combined combustion of biogas and diesel, it not only reduces fuel costs but also increases operational flexibility to meet various power generation needs. For rural biogas projects and other small-scale power generation initiatives, this generator set is an attractive choice.