膜式水冷壁结构燃磷塔的开发与传质传热的数值模拟(Ⅰ)模型建立

Simulation of mass and heat transfer in new phosphoric acid tower with circular water wall(Ⅰ) Model development

针对热法磷酸生产中一方面要求外部供热,另一方面又浪费自身燃烧热的现状,提出能回收余热的新工艺,开发成功膜式水冷壁结构新型燃磷塔.建立了考虑新型燃磷塔内流动、燃烧、传热过程的三维数学模型,通过数值模拟得到塔内湍流场、温度场和组分浓度场的分布.模拟结果显示,燃磷塔内存在明显的涡流射流结构,磷的燃烧主要在喷磷枪雾化角范围内,塔内最高燃烧温度约为1790K,出现在喷磷枪轴线上偏离燃磷塔中心的一侧.烟气出口温度约为970K,与测量值符合较好.

To avoid the energy waste in the production of furnace grade phosphoric acid, a new phosphoric acid tower with circular water wall was designed, which could recover waste heat to produce superheated steam. A three dimensional mathematical model of phosphorus combustion in the new phosphoric acid tower was developed by incorporating the k-ε turbulence model, eddy dissipation turbulent combustion model and P-1 radiation heat transfer model. The streamline field distribution, temperature distribution and species concentration distribution were predicted by numerical simulation. The results showed that phosphorus combustion mainly took place in the injection zone of atomized phosphorus, and the maximum combustion temperature and exit temperature were 1790 K and 970 K respectively which conformed well to practical data.