Generally speaking, four factors need to be considered before selecting waste gas treatment equipment: pollutant type, pollutant concentration, exhaust gas volume and air flow temperature. Due to small air volume and small incinerator, the investment and operation cost are naturally less. Therefore, it is very important to determine the type of exhaust gas, summarize the generation and emission characteristics of exhaust gas, and analyze the whole process. In addition, the small exhaust gas incinerator can reduce the secondary emissions in the oxidation process, that is, less carbon monoxide, nitrogen oxides and carbon dioxide by-products are produced in the conversion process.
1、 Direct fired waste gas incinerator
The direct fired waste gas incinerator uses high temperature catalysis in the closed combustion chamber to accelerate the oxidation and decomposition of organic waste gas. Generally speaking, when the temperature exceeds 1400 ℃, most of the organic pollutants will be converted into carbon dioxide and water, and the conversion rate can reach more than 98%, basically in line with the provisions of relevant departments. Direct combustion incinerator is usually a steel box, and the combustion chamber has its own fuel source, mainly gas burner. In some way, waste heat can be recycled.
2、 Regenerative incinerator (RTO)
RTO can recover heat to a great extent and reduce the consumption of auxiliary fuel both in the preheating stage and in the combustion process. The device is characterized by the use of multiple heat exchange medium beds. The heat exchange medium is heat storage ceramic. The heat released by the oxidation and decomposition of VOCs in the combustion chamber is used to heat the ceramic block. The waste gas of the production line is converted between the two beds to realize heat recovery (up to 97%)
The regenerative incinerator is suitable for the treatment of organic waste gas with high concentration and large air volume, including halogen, etc. it can be operated in batches or continuously, and the VOCs removal rate can reach more than 99%. The disadvantage is that RTO devices are usually large and heavy. Although the current equipment is practical and reliable, RTO has more moving parts than other types of incinerators.
3、 Catalytic combustion equipment
催化燃烧设备是：利用催化触媒的作用，把有机分子在相对较低的温度下（250℃-300℃）分解成CO2和H2O。 优点是：净化比较好，无二次污染，在分解过程产生的热量可以代替维持催化所需的能量，而且能回收利用，比较节能。 缺点是：较适合2000mg/m3—20000 mg/m3中高浓度废气的治理。低浓度≤600 mg/m3废气就需要耗费大量的能耗，净化效率也会降低
Catalytic combustion equipment is: the use of catalytic catalyst, organic molecules at a relatively low temperature (250 ℃ - 300 ℃) into CO2 and H2O. The advantages are: the purification is better, no secondary pollution, the heat generated in the decomposition process can replace the energy needed to maintain the catalysis, and can be recycled and more energy-saving. The disadvantages are: it is more suitable for the treatment of medium and high concentration waste gas from 2000mg / m3 to 20000 mg / m3. If the concentration is less than or equal to 600 mg / m3, a lot of energy consumption will be consumed, and the purification efficiency will be reduced