在焦化厂、煤矿、养殖场、秸秆加工厂，有一笔账常被忽略：那些原本排空烧掉的废气，其实都是钱。焦炉煤气、瓦斯、沼气、秸秆气、兰炭尾气——这些可燃气体热值不低，直接放散不仅浪费能源，还面临环保压力。燃气发电机组要做的，就是把它们变成电。但选型不对，发电效率上不去，投资回收期拉长，项目就失去了意义。

In coking plants, coal mines, livestock farms, and straw processing plants, there is often an overlooked account: the waste gas that was originally discharged and burned is actually money. Coke oven gas, methane, biogas, straw gas, and blue charcoal tail gas - these combustible gases have a high calorific value, and direct release not only wastes energy but also faces environmental pressure. What gas generators need to do is to turn them into electricity. But if the selection is wrong, the power generation efficiency will not improve, the investment payback period will be prolonged, and the project will lose its meaning.

一、先看气源，再定机型

1、 First check the gas source, then decide on the model

燃气发电机组不是“一台机器烧所有气”。不同气源的热值、成分、杂质含量差异极大，直接决定机组能不能稳定运行。

Gas generator sets are not "one machine burns all the gas". The significant differences in calorific value, composition, and impurity content among different gas sources directly determine whether the unit can operate stably.

焦炉煤气的特点是氢含量高，通常在50%到60%之间，燃烧速度快，容易回火放炮，对机组的点火系统和进气控制要求很高。普通天然气机组直接烧焦炉煤气，轻则功率下降，重则频繁停机。

The characteristics of coke oven gas are high hydrogen content, usually between 50% and 60%, fast combustion speed, easy backfire and blasting, and high requirements for the ignition system and intake control of the unit. Ordinary natural gas units directly burn coke oven gas, which can result in a slight decrease in power and frequent shutdowns in severe cases.

瓦斯气（煤层气）甲烷浓度跨度大，高浓度瓦斯可以直接利用，低浓度瓦斯（8%到30%）则需要专门的低浓度发电技术，核心是解决甲烷吸附调变和防爆输送问题。

Gas (coalbed methane) has a wide range of methane concentrations, and high concentration gas can be directly utilized, while low concentration gas (8% to 30%) requires specialized low concentration power generation technology. The core is to solve the problems of methane adsorption regulation and explosion-proof transportation.

沼气的难点在脱硫，硫化氢腐蚀发动机，必须在前端做好净化处理，否则再好的机组也扛不住。

The difficulty of biogas lies in desulfurization, and hydrogen sulfide corrodes the engine. Purification treatment must be done at the front end, otherwise even the best unit cannot withstand it.

秸秆气和生物质气则要重点关注焦油含量。焦油堵塞管道和阀门，是生物质气发电最常见的故障源，对燃气净化系统的要求比机组本身还高。

Straw gas and biomass gas should focus on tar content. Tar blockage of pipelines and valves is the most common source of failure in biomass gas power generation, and the requirements for gas purification systems are higher than those for the unit itself.

二、余热不回收，等于白扔一半钱

2、 Not recycling waste heat is equivalent to throwing away half of the money for nothing

燃气发电机组的发电效率通常在35%到45%之间，意味着超过一半的燃料能量以热量形式排掉了。如果只发电不回收余热，经济性会大打折扣。

The power generation efficiency of a gas-fired generator set is usually between 35% and 45%, which means that more than half of the fuel energy is dissipated in the form of heat. If only generating electricity without recovering waste heat, the economy will be greatly reduced.

正确的做法是配热电联产（CHP）系统：机组排出的高温烟气通过余热锅炉产生蒸汽或热水，缸套冷却水同样可以回收。综合热效率可以从40%左右提升到80%以上。产生的蒸汽可以用于生产工序，热水可以供暖或供生活使用，这部分收益往往能让项目回收期缩短三分之一以上。

The correct approach is a combined heat and power (CHP) system: the high-temperature flue gas discharged by the unit is used to generate steam or hot water through a waste heat boiler, and the cylinder liner cooling water can also be recovered. The comprehensive thermal efficiency can be increased from around 40% to over 80%. The generated steam can be used in production processes, and hot water can be used for heating or daily life, which often shortens the project payback period by more than one-third.

三、选型要看四个硬指标

3、 Selection depends on four hard indicators

燃气适应性是第一位的。问清楚厂家：这台机组能不能稳定烧我这种气？有没有同类型气源的运行业绩？别只看样本参数，要看实际案例。

Gas adaptability comes first. Ask the manufacturer: Can this unit stably burn gas like mine? Do you have any operating performance of the same type of gas source? Don't just look at sample parameters, look at actual cases.

发电效率直接决定燃料成本。同样烧一方气，效率高5个百分点，一年下来电费差距就是几十万。主流燃气内燃机的电效率在40%到45%之间，低于这个水平要慎重。

The power generation efficiency directly determines the fuel cost. Burning the same amount of gas can increase efficiency by 5 percentage points, resulting in a difference of several hundred thousand in electricity bills over the course of a year. The electrical efficiency of mainstream gas internal combustion engines is between 40% and 45%, and caution should be taken below this level.

维护周期和成本是长期账。燃气机组比柴油机组娇气，火花塞、机油、滤芯的更换频率更高。选型时要问清楚：大修周期多长？关键配件是否通用？停机一天损失多少？这些比机组报价更重要。

The maintenance cycle and cost are long-term accounts. Gas turbines are more delicate than diesel turbines, and the replacement frequency of spark plugs, engine oil, and filter elements is higher. When selecting, it is important to ask clearly: How long is the overhaul cycle? Are the key components universal? How much does one day of downtime result in losses? These are more important than the unit quotation.

自动化程度影响人工成本。现代燃气发电机组应该做到一键启停、自动并网、远程监控、故障自诊断。需要专人24小时盯着的机组，运行成本会吃掉大部分利润。

The degree of automation affects labor costs. Modern gas-fired generator sets should achieve one key start stop, automatic grid connection, remote monitoring, and fault self diagnosis. A unit that requires 24-hour monitoring by a dedicated person will consume most of its profits in terms of operating costs.

四、并网还是自用，策略不同

4、 Grid connection or self use, different strategies

如果工厂自身用电量大，并网不上网（自发自用，余电不上网）是最简单的模式，省去审批麻烦，直接抵扣电费。如果余电较多，可以考虑并网售电，但需要满足电网的接入要求，包括频率、电压、功率因数等指标。分布式项目还要考虑孤岛保护、防逆流等配置。

If the factory itself consumes a large amount of electricity and does not connect to the grid (self use, surplus electricity not connected to the grid), it is the simplest mode to save approval trouble and directly deduct electricity bills. If there is a lot of surplus electricity, grid connected sales can be considered, but it needs to meet the requirements of grid connection, including frequency, voltage, power factor and other indicators. Distributed projects also need to consider configurations such as islanding protection and backflow prevention.

对于焦化、煤化这类连续生产的企业，燃气发电机组还可以作为保安电源，在主电网故障时维持关键设备运行，避免停产损失。

For enterprises engaged in continuous production such as coking and coalification, gas-fired generator sets can also serve as a backup power source to maintain the operation of critical equipment in the event of a main power grid failure, avoiding losses due to production shutdowns.

五、算清三笔账再上马

5、 Calculate the three accounts before starting the project

气源账：我的废气量够不够？热值稳定不稳定？有没有季节性波动？气源不足或波动大，机组频繁启停，寿命和维护成本都会失控。

Gas source account: Is my exhaust gas sufficient? Is the calorific value stable or unstable? Is there any seasonal fluctuation? Insufficient or fluctuating gas source, frequent start stop of the unit, and loss of control over lifespan and maintenance costs.

投资账：机组、净化系统、余热回收、电气并网、土建安装，全套下来单位千瓦投资多少？气源是免费的还是需要付费？这些决定了项目能不能算得过来。

Investment account: Unit, purification system, waste heat recovery, electrical grid connection, civil engineering installation. How much is the investment per kilowatt for the complete set? Is the gas source free or does it require payment? These determine whether the project can be considered.

运行账：燃料成本、维护费用、人工、折旧，每度电的综合成本是多少？对比电网电价或自备电厂成本，有没有优势？

Operating account: What is the comprehensive cost per kilowatt hour for fuel costs, maintenance expenses, labor, depreciation? Is there an advantage in comparing grid electricity prices or the cost of self owned power plants?

燃气发电机组的本质，是把别人眼里的“排放负担”变成“能源资产”。选对机型、配好余热回收、算清三笔账，这笔投资才有意义。如果只是买台机器往那一放，气源不匹配、余热不回收，那它就是个烧钱的铁疙瘩。

The essence of gas-fired power generation units is to turn what others perceive as an "emission burden" into an "energy asset". Only by selecting the right model, equipping it with waste heat recovery, and settling the three accounts, can this investment be meaningful. If you just buy a machine and put it there, and the gas source is not matched and the waste heat is not recovered, then it is a burning iron lump.