Jilin Company newly built a 320000t/year styrene unit in 2012. As one of the critical equipment, the steam superheater functions to heat and re-heat the low temperature steam and produce high temperature superheated steam as required by the styrene process. The vertical steam superheater has two furnaces of square modular structure and as required, can heat the superheated steam twice. The project successfully started up on the very first try and has been working well ever since the start-up.
The MTO unit of 680,000t/y coal based new materials project located in Xinjiang built by China Shenhua Coal To Liquid And Chemical Co. Ltd. is the first industrial application of the methanol to olefin technology developed independently by Shenhua group (SHMTO). The CO incineration waste heat boiler, the critical energy saving and air pollutants control equipment in SHMTO unit, is soly developed and designed by Qiyao Energy. Compared with conventional waste heat boilers and those for other MTO units, this CO incineration waste heat boilers has following technical features:
1、The skid mounted fully automatic combustion control system achieves easy, safe and reliable operation;
2、The CO incinerator and waste heat boiler forming a π shape structure can be arranged together with the main equipment of SHMTO unit and thus reduce the area covered;
3、Only steam superheating system and feedwater superheating system are provided. The waste heat boiler shares evaporation and steam generating system together with the main equipment of SHMTO unit. In this way, the boiler itself requires no evaporating and steam generating system, which results in easier operation and improved reliability;
4、The steam superheating system adopts parallel flow together with counter flow so as to prevent the superheater from overburning at high temperature and improve the reliability of the boiler;
The 1.8MT/A heavy oil catalytic unit of SinoPec Zhenghai Refining & Chemicals Co. Ltd. initially was complemented with 3 CO waste heat boilers that generated MP superheated steam by the waste heat recovered from the flue gas discharged by the heavy oil catalytic unit together with some additional gas and fuel oil. To meet the increasingly stringent emission requirements and control the total emission of NOx and SOx of the plant, ZRCC added flue gas de-NOx and de-SOx unit to the heavy oil catalytic unit so as to remove the NOx and SOx contained in the emission discharged from the CO boiler exit. Owing to the large size of the de-NOx and de-SOx unit, original CO boilers had to be dismantled and then replaced by a new CO waste heat boiler together with the de-NOx and de-SOx unit.The actual engineering application of this ZRCC project is the first waste heat boiler with de-NOx & de-SOx unit installed to the catalytic cracking unit in the oil refining industry of China. This technology is to support and lead the development of waste heat boilers for catalytic cracking units in China, and in addition, conforming to the “Green water & blue sky” action initiated by SinoPec, it also shows the way of reconstruction of waste heat boilers in entire SinoPec group. From then on, dozens of waste heat boilers for catalytic cracking units in SinoPec group were designed and reconstructed according to this project, 1.2MT/A 1# catalytic cracking unit of SinoPec Changling Company, 1.4MT/A catalytic cracking unit of SinoPec Qingdao Company, to name a few, and all these boilers reached the emission requirements. This technology plays an important role in expanding the product portfolio, improving the competitiveness and consolidating the market position of Qiyao Energy. As it coincides with the energy saving and emission control requirements vigorously promoted by the country, the waste heat boiler with de-NOx unit for catalytic cracking unit has a broad market.
After the sci-tech novelty retrieval, it is proved that this project is novel in the critical technology research and the execution of the project, and the design of waste heat boiler for catalytic cracking unit in oil refineries is innovative and the technology can produce excellent social and economic benefits. The comprehensive technical level has reached leading level in China.The critical technology in this project has obtained the appraisal certificate of scientific and technical achievement.