陕西科技大学过程装备与控制工程过程装备双语Chapter 13 Utility Systems.pptVIP

Chapter 13 Utility Systems §13.2 Introduction to Process Systems 2. Types of Utility Systems: Steam Generation Systems: (1) Steam system’s definition: 1st sent. (2) Main equipments of a typical steam system: - Boiler (fire tube or water tube) - Steam header system (low, medium and high pressure) - Condensate return system (steam traps, valves, piping, pumps) - Deaerator system Steam systems can include Note: SHP/HP/MP/LP §13.3 Raw Water and Fire Water System Raw water——located above grade; Fire water——underground. §13.4 Boiler Feed Water Treatment Boiler feed water treatment is the process by which suspended and dissolved solids are removed from the waste used in a plant. Clean condensate and demineralized makeup water are deaerated in order to supply boiler feed water (BFW) to multiple BFW pumps. Two or three pumps are used in the pump-around operation. The primary pump typically has one or two backup pumps that are placed in standby mode. Definition: 1st sent. Purpose of removing impurities: (Para.2, 3 sents.) Fig.13.4-1） §13.4 Boiler Feed Water Treatment Basic knowledge about water： Corrosion 1. Definition and mechanism (Para 1: 2 sents.) 2. Corrosion fatigue (Para 2) 3. Prevention (Para 3) 4. Maintaining pH levels in boiler feed water; removing dissolved oxygen from water; using chemical treatments; following established out-of-service and blow-down procedures. Coagulation and Flocculation Chemical Precipitation Mechanism: 1st sent. Key terms: solution line 2 Lime- soda softening process Ion Exchange Process: Demineralization Key terms: resin Charged particles line 1 1. Explain the process. 1st sent. 2. Deaeration (2 sents.) The cooling water (CW) system is used for cooling the various pieces of equipment in the facility in a closed cooling system. The cooling water system is divided into two complementary circuits. One circuit operates on a once-through basis; the other allows