From waste tyres to clean energy: the ‘green revolution’ of fracked gas power generation
Comprehensive Utilisation of Tyre Cracking Gas Purification and Power Generation
Efficient use of clean energy
Tyre thermal-cracking is the process of heating waste tyres in an anaerobic or anoxic environment to break their polymer chains and decompose them, producing cracking gases. The main components of these gases include hydrogen, methane, carbon monoxide and other combustible gases. After purification to remove impurities, in the generator set, the high-temperature and high-pressure gases produced by the combustion of cracked gas push the turbine to rotate, which in turn drives the generator to generate electricity. The whole process realises a magnificent transformation from waste to energy, which not only reduces environmental pollution, but also generates clean electricity, contributing to the diversification of energy structure.
Ⅰ.Tyre cracking gas
Tyre Cracking Gas Tyre cracking is a process whereby waste tyres are converted into valuable products by means of high-temperature atmospheric pressure cracking technology. One ton of waste tyres can be cracked roughly to produce about 45 per cent cracked oil, 35 per cent carbon black, 12 per cent steel wire and 8 per cent non-condensable gas.
Ⅱ. Exhaust fraction
The main components of tyre cracking gas are hydrogen, methane, ethane, ethylene, carbon monoxide and carbon dioxide. However, the proportion varies depending on factors such as the composition of the tyre raw material, the cracking process and conditions. Generally speaking, H2 accounts for about 10 - 20 per cent, methane for about 20 - 30 per cent and CO for 10 - 20 per cent.
Ⅲ. Characteristics of exhaust gases
1. Complex composition: Contains flammable gases such as hydrogen, methane, ethane, ethylene and carbon monoxide, as well as non-flammable gases such as carbon dioxide and hydrogen sulphide. The proportions of these components vary depending on the composition of the tyre, the cracking process and the conditions. For example, in different brands and models of tyres, there are differences in the type and amount of rubber and additives, which can lead to different cracking gas compositions.
2. Better flammability: Flammable components such as hydrogen, methane and carbon monoxide make cracking gases have good flammability. The combustion of these gases releases a large amount of heat energy, which is an important basis for their use in power generation. The high calorific value of combustion provides sufficient energy for power generation.
3. Instability: Fracked gas is less stable due to the presence of flammable and explosive gases, such as hydrogen, and because the proportion of its components may fluctuate. During storage and transport, if it encounters fire, static electricity, high temperature or sudden change in pressure, it is prone to combustion or even explosion. Therefore, it needs to be operated under complete safety measures.
4. Pollution: Hydrogen sulphide and other components in cracked gas are toxic and harmful gases, which will cause harm to the environment and human health if they are directly discharged without treatment. It may also produce pollutants such as sulphur dioxide after combustion, so it needs to be purified before it is utilised.
Ⅳ. Cracked gas internal combustion engine for power generation
01 Gas purification
Cracked gas contains impurities and harmful components, such as hydrogen sulphide, carbon dioxide, etc. If the purification is not thorough, it will affect the combustion effect and the operation of the equipment, and reduce the energy conversion efficiency. Adopting advanced desulphurisation, decarbonisation and other purification technologies can effectively remove impurities, improve the purity of cracked gas, make combustion more complete and thus enhance the energy conversion efficiency.
02Power generation principle and process
The internal combustion engine generates electricity by converting the internal energy released by fuel combustion into mechanical energy, which in turn drives the generator to rotate and converts mechanical energy into electrical energy. The purified tyre cracking tail gas enters the storage tank or buffer tank for storage and pressure stabilisation, and is then transferred to the internal combustion engine through the transmission pipeline. In the internal combustion engine, the exhaust gas is mixed with air in a certain ratio and burned to produce high temperature and pressure gas, which pushes the piston to do work. Finally, the reciprocating motion of the piston is converted into rotary motion through the crankshaft, driving the generator to generate electricity.
03 Technological Advantages
The purified cracked gas is fed into the combustion chamber of the internal combustion engine, mixed with air and ignited. The high-temperature and high-pressure gas produced by combustion expands rapidly and pushes the piston of the internal combustion engine to do work, converting chemical energy into mechanical energy.
The reciprocating motion of the piston of the internal combustion engine is converted into a rotary motion through the crankshaft linkage mechanism, which drives the rotor of the generator to rotate in the magnetic field, thus causing the coil inside the generator to generate an induced current, which achieves the conversion of mechanical energy to electrical energy and ultimately outputs electricity.
Ⅴ. Products
Jiangsu Kelin Yuan specialises in the production and development of various gas-fired internal combustion generator sets, as well as gas purification equipment. This series of products have the characteristics of high reliability, high efficiency and environmental protection, and low maintenance cost. After years of market verification, can meet different user needs.
KeLinYuan internal combustion genset adopts the domestic leading cylinder hybrid direct injection technology, the power range covers 300-5000kW, 2021 4000kW gas internal combustion engine successfully selected by the National Energy Bureau energy field of the first major technology and equipment list.
Advantages: Optimised system integration: Reasonable integration of the purification system, gas generator sets, etc., to achieve synergistic operation of each link, which can reduce energy loss and improve overall efficiency.
Scientific operation and management: Scientific operation and management of the power generation system, including maintenance of equipment, monitoring and adjustment of operating parameters, etc., can ensure stable operation of the system and improve the efficiency of energy conversion.
