瓦斯发电机组烟气余热具有鲜明特征：一是排烟温度高，一般在450～650℃，属于中高品位余热，利用价值高；二是烟气流量随机组负荷变化较为稳定，适合连续回收；三是烟气含少量硫分与水蒸气，低温段易出现酸露点腐蚀；四是余热总量大，可与缸套水余热联合实现梯级利用。同时，瓦斯发电场所属煤矿特殊环境，要求余热系统必须具备防爆、防回火、可靠联锁等安全功能，不能影响主机稳定运行。

The exhaust heat of gas generator sets has distinct characteristics: firstly, the exhaust temperature is high, generally between 450-650 ℃, which belongs to medium to high-grade waste heat with high utilization value; Secondly, the random load variation of the flue gas flow rate is relatively stable and suitable for continuous recovery; Thirdly, the flue gas contains a small amount of sulfur and water vapor, which makes it prone to acid dew point corrosion in the low-temperature range; Fourthly, the total amount of waste heat is large, which can be combined with the waste heat of cylinder liner water to achieve cascade utilization. At the same time, gas power generation sites belong to the special environment of coal mines, and it is required that the waste heat system must have safety functions such as explosion prevention, backfire prevention, and reliable interlocking, and cannot affect the stable operation of the host.

烟气余热回收主要技术路线

Main technical routes for flue gas waste heat recovery

（一）余热锅炉产蒸汽

（1） Waste heat boiler produces steam

在机组排烟端设置热管式或水管式余热锅炉，回收烟气热量产生0.4～1.6MPa蒸汽，用于矿区生产、采暖、洗浴供热。该技术成熟可靠、投资适中，可提高系统热效率8%～15%，是应用最广泛的方案。

Install heat pipe or water pipe waste heat boilers at the exhaust end of the unit to recover heat from flue gas and generate 0.4-1.6MPa steam, which is used for production, heating, and bathing heating in mining areas. This technology is mature and reliable, with moderate investment, and can improve the system's thermal efficiency by 8% to 15%, making it the most widely used solution.

（二）余热供暖及供热水

（2） Waste heat heating and hot water supply

通过换热器将烟气热量转换为热水，用于办公楼、宿舍采暖及职工生活热水。在北方矿区采暖周期长，供热收益更为明显。

By using a heat exchanger to convert the heat from flue gas into hot water, it can be used for heating office buildings, dormitories, and employee living hot water. In northern mining areas, the heating cycle is longer and the heating benefits are more significant.

（三）余热驱动吸收式制冷

（3） Waste heat driven absorption refrigeration

利用余热蒸汽或热水驱动溴化锂制冷机组，为厂房、抽采站等提供空调冷水，减少电制冷消耗，提升夏季节能效益。

Using waste heat steam or hot water to drive lithium bromide refrigeration units, providing air conditioning cold water for factories, extraction stations, etc., reducing electric refrigeration consumption, and improving summer energy efficiency.

（四）联合循环补汽发电

（4） Combined cycle supplementary steam power generation

大中型电站可采用“燃气发电+余热锅炉+汽轮发电机”联合循环，将蒸汽再次转化为电能，整体发电效率可提升5%～8%。

Large and medium-sized power stations can adopt a combined cycle of "gas power generation+waste heat boiler+steam turbine generator" to convert steam into electrical energy again, which can improve the overall power generation efficiency by 5% to 8%.

（五）梯级综合利用

（5） Cascade comprehensive utilization

采用“高温烟气产汽发电—中低温热量供暖制冷—缸套水预热补水”的梯级利用模式，系统综合能源利用率可达75%～85%，节能效果最优。

The cascade utilization mode of "high-temperature flue gas steam generation power generation - medium and low-temperature heat heating and cooling - cylinder liner water preheating and replenishment" is adopted, and the comprehensive energy utilization rate of the system can reach 75% to 85%, with the best energy-saving effect.

关键技术与安全保障

Key Technologies and Security Assurance

瓦斯发电余热回收需重点解决安全与稳定运行问题。一是合理匹配余热锅炉容量，适应瓦斯浓度波动与机组负荷变化；二是采用耐腐蚀换热材料，减缓腐蚀；三是设置防爆烟道、紧急排烟旁路及超温超压联锁，满足煤矿防爆安全要求；四是实现余热系统与机组DCS联动控制，确保不影响主机运行参数。

The recovery of waste heat from gas power generation needs to focus on addressing safety and stable operation issues. One is to reasonably match the capacity of the waste heat boiler to adapt to fluctuations in gas concentration and changes in unit load; Secondly, corrosion-resistant heat exchange materials are used to slow down corrosion; The third is to set up explosion-proof flues, emergency smoke exhaust bypasses, and over temperature and over pressure interlocks to meet the explosion-proof safety requirements of coal mines; The fourth is to achieve linkage control between the waste heat system and the unit DCS, ensuring that it does not affect the operating parameters of the host.