RTO热力平衡核算及天然气消耗量影响因素分析

以某船舶涂装车间运行数据为依据，建立了蓄热式高温氧化炉（Regenerative Thermal Oxidizer，RTO）的热力平衡关系式，核算了RTO空载和满载运行的数据，验证了炉温与挥发性有机化合物（Volatile Organic Compounds，VOCs）浓度的关系；讨论了排风量、沸石转轮浓缩倍率、换热器热利用率和VOCs浓度四个关键参数对天然气消耗量的影响.结果显示，入炉VOCs浓度每增加1000mg/Nm³，炉温上升约21℃，排风量越小，沸石转轮浓缩倍率、换热器热利用率和VOCs浓度越大，天然气消耗量越低.基于本研究建立的热平衡方程，结合RTO实际工程应用中的注意事项，结果表明，在烘干阶段按照工艺要求的3次/h确定车间最小排风量，将沸石转轮浓缩倍率设定为10~14倍，选用换热器热利用率在0.7以上的换热器能在保证RTO安全运行的前提下显著降低天然气消耗量.

Thermodynamic balance calculation of RTO and analysis of influencing factors of natural gas consumption

The heat balance equation of Regenerative Thermal Oxidizer (RTO) was established according to actual operating condition of a painting workshop. The no-load and full-load operation data of RTO was calculated, and the relationship between furnace temperature and concentration of Volatile Organic Compounds (VOCs) was verified. On this basis, the influence of four key parameters of exhaust air volume, zeolite runner concentration ratio, heat exchanger heat utilization rate and VOCs concentration on natural gas consumption were discussed. The results show that the furnace temperature increased by about 21℃ for each 1000mg/Nm³ growth in the incoming VOCs concentration. The smaller exhaust air volume made the higher zeolite rotor concentration multiplier and heat exchanger thermal utilization rate, and thus resulted in higher VOCs concentration in the RTO. This results could reduce natural gas consumption. The heat balance equation was established in this paper, combined with the considerations in engineering application of RTO. When painting was being dryed, the minimum exhaust air volume of painting workshop was establed on the basis of 3 times/h. The concentration multiplier of zeolite rotor was set to 10~14times, and the heat exchanger with heat utilization rate above 0.7 was selected, which could significantly reduce the natural gas consumption, and ensuring the safe operation of RTO.