The urea hydrolysis technology for ammonia production has been widely used in the preparation of denitration reducing agents for thermal power units. However, if the quality of urea is not up to standard, the urea hydrolyzer will leak, and the drainage from the urea hydrolyzer will be reused in the condenser, which will cause great harm to the thermal system. The article analyzes the serious salt accumulation and superheater tube explosion in the water and steam system caused by the leakage of a urea hydrolyzer in a coal-fired unit, and proposes a solution to the salt accumulation problem. The problem has been successfully solved, after the unit is started, all quality criterion of water and steam meet the requirements of Quality Criterion of Water and Steam for Power Plant and Steam-generating Equipment (GB/T 12145—2016). This article provides a solution for analyzing and treating the cause of salt accumulation in the water and steam system for reference.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |