1 General provisions
1.0.1 This code is formulated to implement relevant national laws and regulations and energy industry policies, reduce the total energy consumption and water consumption while improve the design level of steam condensate system in chemical plant, and ensure the safety, reliability, technology advancement, flexible operation and economic rationality of the steam condensate system.
1.0.2 This code is applicable to the design of steam condensate system in constructed, renovated and extended engineering chemical plant.
1.0.3 The design of steam condensate system in chemical plant shall not only meet the requirements of this code, but also comply with relevant current national standards.
2 Terms
2.0.1 condensate
water formed by steam condensation
2.0.2 open system
system in which condensate is directly exposed to the atmosphere
2.0.3 close system
system in which condensate is not directly exposed to the atmosphere
2.0.4 condensate recovery ratio
percentage of actually recovered condensate in recoverable condensate
2.0.5 operating pressure for steam trap
pressure at the inlet of the steam trap under operating conditions in the condensate recycling system
2.0.6 operating back pressure for steam trap
pressure at the outlet of the steam trap under operating conditions in the condensate recycling system
2.0.7 maximum (allowed) working back pressure of steam trap
maximum (allowed) pressure at the outlet when the steam trap can operate correctly under operating conditions in the condensate recycling system
2.0.8 specific pressure drop
on-way resistance loss per meter of condensate pipeline
2.0.9 condensate tank
water tank for collecting and storing condensate in a condensate recycling system.
2.0.10 condensate recycling tank
water tank arranged in front of the condensate treatment system for collecting and storing buffer condensate
2.0.11 open-type gravity condensate recycling system
open condensate recycling system using condensate water potential as power
2.0.12 closed-type back pressure condensate recycling system
closed-type condensate recycling system using back pressure of steam trap as power
2.0.13 closed-type full tube condensate recycling system
condensate recycling system using mixed power of condensate gravity and back pressure
2.0.14 closed-type pressurized condensate recycling system
closed-type condensate recycling system with forced recovery by water pump or other pressurizing facilities
2.0.15 removed iron, removed salt condensate treatment system
treatment system for condensate containing iron, mechanical impurities and trace dissolved salt during start-up, operation and shutdown of steam-water system
2.0.16 removed iron, removed oil, removed salt combined-type condensate treatment system
treatment system for condensate containing iron, mechanical impurities, a small amount of oil and trace dissolved salt during start-up, operation and shutdown of steam-water system
3 Basic principles of system design
3.0.1 The design of steam condensate system shall follow the national policies of energy conservation, emission reduction and environmental protection, fully recover and utilize the heat energy of steam condensate, reduce the heat pollution to the environment, and improve the reuse rate of softened water and desalted water.
3.0.2 The design of steam condensate system shall be combined with that of steam system, and meet the requirements of Article 9.0.5 of the current national standard GB/T 50655-2011 Code for design of steam system in chemical plant, and the condensate recovery ratio shall be greater than 80%.
3.0.3 Two types of condensate, which may be polluted and may not be polluted, shall be recycled separately.
3.0.4 Technical and economic analysis shall be carried out when recycling the condensate which may be polluted. For condensate having recycling value, the steam condensate system shall be equipped with water quality monitoring and water treatment facilities. If it is really difficult to recycle and the economic benefit for recycling is poor, the condensate may not be recycled temporarily, but its heat energy shall be fully utilized.
3.0.5 The quality of condensate after recycling and treatment shall meet the requirements of water consumption index of boiler or production device, and if the water quality after treatment still fails to meet the requirements of water quality index, other uses may be considered or the condensate may be discharged after being treated to meet the environmental protection standard.
3.0.6 The steam condensate of heated strong corrosive substances shall not be recycled. The condensate of heating oil tank and toxic substances shall not be recycled, and shall be discharged after being treated to meet the environmental protection standard.
3.0.7 The turbine condensate should be recycled by a separate system, which may be directly recycled to a deaerator at high temperature.
3.0.8 The steam condensate shall be flashed by cascade according to pressure grade for multiple utilization, and condensate and its waste heat shall be utilized by cascade according to heat energy grade.
Foreword i
1 General provisions
2 Terms
3 Basic principles of system design
4 Design of condensate recovery and treatment system
4.1 Design conditions
4.2 System selection
4.3 system determination
5 Selection and calculation of main equipment
5.1 Selection of condensate recovery equipment
5.2 Selection of condensate treatment equipment
5.3 Calculation of steam traps
6 Hydraulic calculation of condensate pipeline
7 Monitoring for condensate quality and system control
7.1 Monitoring for condensate quality
7.2 Control system and instrument configuration
Annex A Data sheet for condensate recovery
Explanation of wording in this code
List of quoted standards
