In PSA urea decarburization technology field, Tianli has applied for 9 national patents and 2 international patents since 2001, among of which 4 national patents have been granted, their patent number respectively as follows: ZL01108694.7, ZL 01108691.2, ZL200410021697.7 and ZL200410046598.4. Especially, the decarburization invention patent technology of No. ZL200410046598.4 was accepted as a revolutionary progress, for whole technology not using the power systems (like vacuum pumps, solution pumps, blowers) and further avoiding effective gas (such as H2, CO, N2 and CO2) loss, which nearly help users save more than tens of million Yuan of operation fee every year. The decarburization patent technology has been successfully applied in many large scale units such as Jiangsu Jiangsu Hengsheng fertilizer CO., LTD., Shanxi Lanhua Sci-tech Venture CO.Ltd, Guizhou Yihua Company, Chongqing Yihua Company, Guizhou Chemical Industry CO., LTD, Guizhou Kailin (Group) CO., LTD and Shandong Ruixing Chemical Indust. Group CO., LTD. etc. , which treatment capacity is more than 100,000 Nm3/h with operation pressure 1.6-3.0MPa. Compared to the traditional decarburization method, synthetic ammonia cost lower 85 ~ 150 Yuan/ton (save different costs to different wet decarburization method, electricity 0.38 Yuan/KWh) comparing to traditional decarburization method.
When using 80~99.5%(v) oxygen to make shift gas , the above patent technology can control the total amount of carbon dioxide, carbon monoxide and methane of shifted-gas below 10ppm, and the total sulfur content below 0.1ppm. It can totally replace rectisol process and liquid nitrogen washing process to purify product carbon dioxide above 99% (V) and product hydrogen above 99.999% (V), and increase the concentration of hydrogen sulfide and organic sulfur above 25% (V). In addition, its product hydrogen recovery is slightly higher than liquid nitrogen wash process. Except vacuum pump needed in sulfur concentrating parts, there is no power equipment needed in the main flow process of the whole unit. Compared to rectisol process and liquid nitrogen washing process, the synthetic ammonia cost save 150 ~ 200 yuan/ton(electricity 0.38 Yuan/KWh), and its investment is lower than that of rectisol process and liquid nitrogen wash process.
This is the 400,000 ton/a PSA urea decarburization unit of Guizhou Chemical Co., Ltd. of Hubei Yihua Group. Its operation indexes: shift gas 125,000 Nm3/h, CO2 content of purified gas 0.2～0.25%(V), product CO2 purity 97.5～98%(V), hydrogen recovery 99.5%(V), nitrogen recovery 95%(V), ammonia power consumption 5 KWh/ton(including program control valve, instrument, control system, etc.).
Shandong Yankuang Group Co., Ltd.
PSA Urea Decarburization Technology
This is the PSA desulfation and decarburization unit (including sulfur concentration) of Shandong Yanzhou Coalmining Company Limited. Its operation indexes: feed gas 70,000 Nm3/h, CO2 content of feed gas about 15%(V) and total sulfur content 0.7~0.8%(V), CO2 content of purified gas below 5ppm, product CO2 purity 97.5～98%(V), concentration of hydrogen sulfide and organic sulfur above 25% (V), hydrogen recovery 99.5%(V), product CO2 recovery92%(V).