喷钙脱硫用活化器喷头的研究

STUDY OF ACTIVATOR NOZZLE FOR LIMESTONE INJECTION DESULFURIZATION

炉内喷钙脱硫是一种适合我国国情的烟气脱硫工艺。其技术关键之一，是要使随烟气流出锅炉的钙吸着剂与雾化水滴相撞，使吸着剂所含ＣａＯ转化为活化的Ｃａ（ＯＨ）_２，进一步与烟气二氧化硫相作用，从而提高总的脱硫效率．在该活化过程中，雾化喷头的选型和结构十分关键，它既要能使水滴与吸着剂有最大的碰撞效率，又要避免（或减少）水滴与水滴的相互碰撞；既要求水滴不会沾活化器的器壁导致结垢，或随烟气流出活化器而影响下游，又要求雾化过程用动力少．作者研制了一种用压缩空气雾化的水喷头，冷试表明，该喷头在喷角、滴径分布、雾化能耗等方面全面达到了设计要求．在活化装置中试（烟气量１０００Ｍ￣３／ｈ）进行的脱硫试验表明，该喷头活化效果良好．

Furnace Limestone injection is a flue gas desulfurisation technology most adaptable to China's concrete conditions. One of the keys to the commercialization of this technology is to convert the adsorbent CaO into active Ca (OH)_2 by colliding the adsorbent contained in the flue gas exitting the boiler with water droplets of optimum dimensions to enhance reaction between the adsorbent and SO_2 and raise oveall desulfurization efficiency. In this activation process, the type and construction of the atomizing nozzle is especially important. It should maximize the colliding efficiency of the water droplets with the adsorbent. It should avoid wetting, fouling and scaling of the inner activator walls and the presence of unevaporated droplets at the exit of the activator, and also minimize energy consumption of the atomizing process. The authors developed a twin-fluid atomizing nozzle suitable for this purpose. Cold atomizing tests showed that it satisfies the droplet size distribution, spray angle and energy consumption requirements. Desulfurization tests conducted on a pilot sacle activator (flue gas 1000m￣3/h) showed that the SO_2 removal reaches a satisfactroy level.