某4×300 MW机组液氨改尿素工程技术经济分析

Techno-economic analysis on liquid ammonia to urea project of 4×300 MW power unit

基于两种尿素制氨工艺,以某4×300MW机组液氨改尿素工程为例,在技术参数、工程量、适应能力、投资估算、能耗物耗及运行成本方面对电加热型尿素热解(方案1)、烟气加热型尿素热解(方案2)、尿素普通水解(方案3)和尿素催化水解(方案4)进行技术经济分析,结果表明,改造工程量由大到小的顺序为方案2、方案1、方案4、方案3;方案1和方案2在响应负荷变化能力和环境适应性方面优于方案3和方案4;方案3和方案4在适应低负荷能力和运行可靠性方面优于方案1和方案2;方案2投资最高,方案1和方案3最低且两者基本持平;方案1的能耗和物耗水平最高,方案2最低;方案2、方案3和方案4的运行成本相近,方案1的运行成本约为其余3种方案的1.4倍;从长远来看,方案2相较于方案1更有优势;从技术、投资和适应能力等方面统筹考虑,方案4最具有竞争力。分析结果可为液氨改尿素工程提供借鉴和指导。

Based on the introduction of two kinds of urea to ammonia processes,liquid ammonia to urea project in 4×300M W units taken as example,the techno-economic analysis of electric heating urea pyrolysis(scheme one),flue gas heating urea pyrolysis(scheme two),common urea hydrolysis(scheme three)and urea catalytic hydrolysis(scheme four)were carried out in terms of technical parameters,engineering quantity,adaptability,investment estimation,en-ergy and material consumption and operating cost.According to the analysis results,the sequence of engineering quan-tity from large to small is scheme two,scheme one,scheme four,scheme three.Scheme one and two are superior to scheme three and four in responding to load change capacity and environmental adaptability,while scheme three and four are superior to scheme one and two in adapting to low load capacity and operation reliability.Scheme two has the highest investment,while scheme one and three have the lowest investment and they are almost equal.Scheme one has the highest level of energy and material consumption,while scheme two has the lowest level.The operating cost of scheme two,three and four is similar,and the operating cost of scheme one is about 1.4 times of the other three schemes.In the long run,scheme two is more advantageous than scheme one.In terms of technology,investment and adaptabilty,scheme four is the most competitive.The comprehensive analysis present in this paper can provide effec-tive reference and guidance for ever-increasing liquid ammonia to urea projects during recent years.