Natural Gas

Natural gas, the most common combustible gas, consists mainly of methane (CH4), which makes up over 85% of its content. It is ideal for gas internal combustion generator sets, so there is usually no need to worry about the specific composition or calorific value when choosing equipment.

During oil extraction, associated gas is released from the wellhead alongside crude oil. Collecting this associated gas involves separating and purifying it from the crude oil. The energy density of the associated gas is then increased through compression before it is transported via pipelines to the Liyu gas internal combustion unit. Here, the associated gas is mixed with air and burned to create high-temperature, high-pressure gas, which drives the unit to generate electricity.

The Liyu gas generator set efficiently converts oil field gas into electrical energy, which can be used on-site for production activities. This process effectively prevents methane release into the atmosphere, reduces oil consumption, and delivers significant economic and environmental benefits.

The Main Types Of Natural Gas

• Natural Gas: This is pipeline natural gas delivered through municipal systems. It is primarily CH4 with small amounts of ethane (C2H6) and other        hydrocarbons, offering a calorific value of approximately 8000–8500 kcal/Nm³.
• CNG (Compressed Natural Gas): This is natural gas that has been compressed and transported in tank trucks. Its composition is the same as pipeline natural gas.
• LNG (Liquefied Natural Gas): A more advanced form of CNG, LNG is natural gas that has been cooled and pressurized to become a liquid. It maintains the same composition as natural gas.
• Shale Gas and Combustible Ice: These unconventional sources contain higher CH4 levels compared to conventional natural gas. Shale gas is found in deep shale layers, while combustible ice is located in deep-sea deposits. Both face challenges related to current extraction and transportation technologies but hold significant future potential.
• Wellhead Gas: Also known as oilfield associated gas, this is natural gas extracted from oil fields. Its composition varies but generally includes 50-80% CH4, 20-40% ethane and propane, around 5% higher hydrocarbons, and about 10% inert gases like N2 and CO2, with some H2S.

Selected Case Studies

Biogas

Biogas is produced through the anaerobic fermentation of organic matter and can be classified based on its source:

The Main Types Of Biogas

• Biogas: This type of biogas comes from materials such as feces, kitchen waste, straw, and by-products from alcohol production, slaughterhouses, and paper mills. It generally contains 55-60% CH4 and minor amounts of H2S. Other organic materials like corn silage, rice straw, wheat straw, and various leaves can also be used.
• Landfill Gas: Generated from the decomposition of waste in landfills, this biogas also contains about 55-60% CH4 along with some H2S. Anaerobic bacteria in the landfill produce biogas as waste decomposes in the absence of air.
• Sewage Treatment Gas: Produced during the treatment of urban sewage, this biogas comes from the anaerobic digestion of sludge collected from sedimentation tanks.

Selected Case Studies

Coalbed Methane

Coalbed methane is a type of gas found in coal seams, primarily composed of CH4. It can be classified into three categories:

LIYU'S Solution

After undergoing dehydration, dust removal, boosting, and stabilization, the gas is transported to the Liyu gas-specific generator set for fuel operation. This process drives the piston, allowing the gas engine to generate electricity, while the waste heat produced can be utilized for heating.

Most coal mines contain significant amounts of coal mine gas and abandoned mine methane, which can be effectively harnessed for electricity and heat generation. The robust utilization of coal mine gas for power generation not only conserves energy and reduces emissions but also transforms potential hazards into valuable resources. This approach enhances safety in coal mining operations and lowers greenhouse gas emissions, resulting in substantial economic, environmental, and social benefits.

The Main Types Of Coalbed Methane

• Coalbed Methane: This is the gas extracted directly from coal seams, often with a CH4 content of 95-99%, making it highly pure.
• High-Concentration Gas: This gas contains 30-60% CH4 and is relatively simple in composition, primarily consisting of methane with minor amounts of air (N2 and O2) and few other impurities.
• Low-Concentration Gas: With a CH4 content of less than 30%, this gas typically has around 5-20% CH4, with the remainder being air.

Selected Case Studies

Industrial Gases

Industrial gases, often rich in CO and H₂, include smelting furnace exhaust gases generated from ferroalloy plants, steel mills, coking facilities, iron foundries, and other industrial smelting operations.

Industrial Gas Application Process

The industrial gas undergoes a pre-processing phase that includes desulfurization, dust removal, water cooling (and pressurization if necessary), and electric coking. This processed gas is then used as fuel for the Liyu gas engine, which drives a generator to produce electricity. To meet nitrogen oxide emission standards, the engine exhaust may require denitration.

Multiple gas-fired generator sets can be integrated into a single power generation unit, creating a compact energy station that efficiently generates electricity using industrial gas. These small energy stations can be combined into larger gas-fired power plants, allowing for greater adaptability to varying production capacity needs. This flexibility enables precise control over power generation utilization, ensuring optimal operating conditions and continuous, efficient service. In addition to powering production and daily activities, this process effectively addresses environmental issues related to smelting furnace gas.

The Main Types Of Industrial Gases

• Ferroalloy Furnace Tail Gas: Comprising CO (50-85%), H₂ (2-14%), CH₄ (0-6.5%), and trace amounts of CO₂, N₂, O₂, and H₂O, this gas has a low calorific value of 1680-2760 kcal/Nm³. Its exact composition can vary based on raw materials and production conditions.
• Coke Oven Gas: A by-product of coking bituminous coal, this gas typically contains 25-30% CH₄, 50-60% H₂, 5-10% CO, and small amounts of CO₂, N₂, O₂, and other gases. With a calorific value of 4000-4500 kcal/Nm³, its high H₂ content and low CH₄ value limit the use of most generator sets; however, specialized models, such as those from Liyu, can operate with minimal power loss.
• Blast Furnace Gas: Produced during ironmaking in blast furnaces, this gas has negligible CH₄, 1-3% H₂, 26-30% CO, 6-12% CO₂, 55-60% N₂, and small quantities of SO₂ and other impurities. Its calorific value is low, around 800-1000 kcal/Nm³, and it contains significant dust.
• Converter Gas: Generated in the converter steelmaking process, this gas typically contains 65-80% CO, 2-3% H₂, and the remainder is CO₂, N₂, and O₂. It has a calorific value of approximately 1500-2000 kcal/Nm³.

For over 30 years, Liyu has been at the forefront of gas internal combustion engines, evolving with the shifting gas market. Our engines efficiently convert natural gas, coalbed methane, biogas, and industrial gases into green electricity, reducing emissions, cutting costs, and enhancing efficiency.

As the industry embraces new opportunities, Liyu remains dedicated to advancing energy technology, broadening our product applications, and delivering exceptional service to our customers.