1 General principles
1.0.1 In order to unify the calculation methods of industrial boiler plants and small and medium-sized power station boilers, and make the boiler plant design fully comply with the relevant national policies, this code specifies fundamental provisions on the items concerned, requirements, basic equations, methods and data that shall be based on in the process design of boiler plants.
1.0.2 This code is applicable to the process design calculation related to the boilers in industrial, civil and enterprise-owned boiler plants and small and medium-sized power plants (stations) with coal, oil, natural gas and coal gas as fuel, with the rated steam pressure of boiler not greater than 9.81MPa and the rated steam temperature not greater than 540℃. This code may serve as a reference for the expanded and reconstructed boiler plants and small and medium-sized power plants (stations).
1.0.3 This code is compiled according to national codes and standards, combined with the situation of industrial boilers and small and medium-sized power station boilers. In the process of implementation, if it is found to be inconsistent with the superior mandatory standards or new standards are promulgated, the superior standards and newly promulgated standards shall prevail.
2 Heat load in boiler plant and calculation of boiler equipment
2.1 Heat load in boiler plant
2.1.1 Heat load calculation principle.
1 The heat load of boiler plant shall be determined according to the planned capacity of boiler plant and the scale of phased construction after investigation and implementation of short-term and long-term heat load.
2 The design heat load shall be determined according to the general situation of heat source, heat source distribution, heat supply and heating parameters within the heating range, and shall meet the following requirements:
1) Industrial steam heat load: the current situation of each heat user and the nature of the planned heat load, steam consumption parameter and method, heat consumption method, recovered water situation and the monthly average steam consumption and hours of steam consumption in the last year shall be investigated and obtained, and the maximum, average and minimum hourly steam consumption in winter and summer shall be determined according to the hourly steam consumption of each heat user on typical days in different seasons. For main heat users, the heat load curve for typical days in different seasons and the annual continuous heat load curve shall be drawn.
2) Heating load: heating load is a seasonal heat load, and its change depends on the change of outdoor calculated temperature. The short-term and long-term heating user types within the heating scope shall be obtained, and the heating area and comprehensive heating indicator shall be calculated respectively. The hourly heat load and average heat load in heating period corresponding to each outdoor calculated temperature (from the initial heating temperature to the outdoor calculated heating temperature) are calculated according to the local meteorological data to draw the heating load curve in heating period.
When the heated building is equipped with ventilation and air conditioning heat load, the calculated heating load shall include the heat load for ventilation and air conditioning of the building to heat fresh air.
The selection of heating indicator shall meet the requirements of the current national standard Design code of district heating network.
Note: The initial heating temperature is generally the daily average outdoor temperature +5℃.
The daily average temperature over the years that is not ensured for an average of 5 days in a year shall be adopted as the calculated outdoor heating temperature.
3) Heat load of domestic hot water: hot water load is a year-round load with seasonal variation characteristics. The area of residential and public buildings, heating indicator of domestic hot water, etc. shall be obtained, and the average heat load and maximum heat load of domestic hot water shall be calculated.
4) Condensate recovery: there are many steam users in industrial enterprises, and the loss of steam and water is large. Therefore, condensate shall be recovered as much as possible to reduce the cost of water production. Industrial condensate recovery shall be determined after technical and economic comparison.
5) Prediction of heat load growth: in addition to obtaining and verifying the current heat load data, the expected heat load and the long-term planned heat load must be calculated according to the approved heat consumption of construction projects and the natural growth rate of industrial development, and the scale and final scale of boiler plant construction by stages may be determined accordingly.
3 Cautions for heat load determination:
1) The steam consumption of boiler plant, the loss of steam and water in boiler plant and the loss during heat pipeline transmission shall be considered.
2) Different industrial enterprises have different production shifts, process flows and operation sequences, and the maximum steam consumption cannot occur at the same time, so the simultaneous rate must be included in the heat load statistics.
3) If the main heat load fluctuates greatly, various measures shall be taken to stabilize the heat load, such as arranging a heat accumulator.
4) It is necessary to consider various operating conditions of enterprise heating system and the decrease of heat load after energy-saving technical transformation.
5) For the heat load in winter, the heating indicator shall be comprehensively determined according to the factors such as the calculated outdoor temperature of heating and the types of local buildings and structures specified in specifications.
2.1.2 Calculation of heat load.
1 The maximum, minimum and average heat load and parameters of heat users in different seasons shall be converted into steam supply parameters, steam flow rate or heat supply at boiler plant outlet. It shall be considered that the heating indicator has included 5% heat loss of pipe network when calculating the heating load and domestic hot water heat load according to the heating indicator.
2 When heat loads of heat users are superimposed, the utilization of simultaneous rate shall meet the following requirements:
1) For the main heat users with stable production heat load, on the basis of obtaining their typical daily heat load curves in different seasons, when heat loads are superimposed, the simultaneous rate shall not be calculated.
2) Secondary heat users with small or instable production heat load shall be multiplied by the simultaneous rate when maximum heat loads are superimposed.
3) When the heating load as well as air-conditioning cooling heat load and hot water heat load for living are superimposed, the simultaneous rate shall not be calculated.
2.1.3 Conversion of heat load. Generally, the heat load data obtained varies greatly with the parameters and quantity of heating medium, and must be converted into the parameters and quantity of heating medium at the outlet of boiler plant before comprehensive sorting. The conversion equation is as follows:
Foreword i
1 General principles
2 Heat load in boiler plant and calculation of boiler equipment
2.1 Heat load in boiler plant
2.2 Boiler equipment
3 Calculation of fuel combustion
3.1 Basic requirement
3.2 Sorting out of calculation conditions
3.3 Checking calculation of fuel
3.4 Air consumption for fuel combustion
3.5 Gas out of fuel combustion
3.6 Calculation of fuel consumption
3.7 De-sulfur agent for CFB boiler
3.8 Acid dew point of flue gas
4 Thermal system and calculation of equipment
4.1 Steam/water pipeline
4.2 Deaeration/boiler water supply system and equipment
4.3 Boiler blow-down system and equipment
4.4 Boiler dosing system and equipment
4.5 Desuperheating/decompression system and equipment
4.6 Steam trap/water drainage system
4.7 Industrial water system
4.8 Variable-pressure type steam accumulator
4.9 Steam sub-cylinder
4.10 Steam flasher volume
5 Calculation of flue gas, air system and fan
5.1 Flue gas and air system
5.2 Fan
6 Calculation of pulverized coal preparation system and equipment
6.1 Basic requirement
6.2 Coal mill
6.3 Heat calculation of pulverized coal preparation system
6.4 Aerodynamic calculation of pulverized coal preparation system
6.5 Auxiliary equipment of pulverized coal preparation system
7 Calculation of de-dust and ash/slag system
7.1 De-duster
7.2 De-ash/slag system
8 Calculation of emission of gas pollutant and chimney process
8.1 Basic requirement
8.2 Calculation of emission of chimney pollutant
8.3 Calculation of chimney height
8.4 Calculation and checking of inner diameter of chimney exit
9 Calculation of fuel oil system and equipment for oil-fired boiler
9.1 Supply of fuel oil
9.2 Hydraulic calculation of fuel oil pipeline
9.3 Calculation of intermediate oil chamber
9.4 Calculation of volume of waste oil treatment pond
9.5 Calculation of fuel oil heater
9.6 Calculation of fuel oil filter
9.7 Selection and calculation of oil feed pump and oil supply pump
10 Calculation of fuel gas system and equipment for gas-fired boiler
10.1 General requirements
10.2 Calculation of pressure regulator
10.3 Calculation of fuel gas/liquid knock-out drum
10.4 Hydraulic calculation of fuel gas pipeline
Annex A Local resistance coefficient of flue gas, air and pulverized coal pipeline
Annex B Relationship of combustion features, explosiveness and volatiles of fuel coal
Annex C Relationship between selection of pulverized coal preparation system and coal ignition temperature
Annex D Table of parameters for wheel-type mill series
Annex E Table of parameters for bowl-type mill series
Annex F Table of parameters for ball-ring type mill series
Annex G Table of parameters for S-type mill series
Annex H Diagram of correction coefficient of milling output for S-type fan mill
Annex J Relationship of air humidity and dew point
Annex K Specific heat capacity of gases in average constant pressure
Annex L Maximum flue gas flow velocity and amount at exit of conical chimney under negative and positive pressure
Annex M Maximum flue gas flow velocity and amount at exit of columnar chimney under negative pressure
Annex N Maximum flue gas flow velocity and amount at exit of columnar chimney under zero pressure at inlet
Annex P Structures of chimney and flue gas channel as well as anti-corrosion measures
Explanation of wording in this code
Standard
HG/T 20680-2011 Code for Process Calculation of Boiler Plant Design (English Version)
Standard No.
HG/T 20680-2011
Status
valid
Language
English
File Format
PDF
Word Count
75000 words
Price(USD)
2250.0
Implemented on
2011-8-1
Delivery
via email in 1 business day
Detail of HG/T 20680-2011
Standard No.
HG/T 20680-2011
English Name
Code for Process Calculation of Boiler Plant Design
1 General principles
1.0.1 In order to unify the calculation methods of industrial boiler plants and small and medium-sized power station boilers, and make the boiler plant design fully comply with the relevant national policies, this code specifies fundamental provisions on the items concerned, requirements, basic equations, methods and data that shall be based on in the process design of boiler plants.
1.0.2 This code is applicable to the process design calculation related to the boilers in industrial, civil and enterprise-owned boiler plants and small and medium-sized power plants (stations) with coal, oil, natural gas and coal gas as fuel, with the rated steam pressure of boiler not greater than 9.81MPa and the rated steam temperature not greater than 540℃. This code may serve as a reference for the expanded and reconstructed boiler plants and small and medium-sized power plants (stations).
1.0.3 This code is compiled according to national codes and standards, combined with the situation of industrial boilers and small and medium-sized power station boilers. In the process of implementation, if it is found to be inconsistent with the superior mandatory standards or new standards are promulgated, the superior standards and newly promulgated standards shall prevail.
2 Heat load in boiler plant and calculation of boiler equipment
2.1 Heat load in boiler plant
2.1.1 Heat load calculation principle.
1 The heat load of boiler plant shall be determined according to the planned capacity of boiler plant and the scale of phased construction after investigation and implementation of short-term and long-term heat load.
2 The design heat load shall be determined according to the general situation of heat source, heat source distribution, heat supply and heating parameters within the heating range, and shall meet the following requirements:
1) Industrial steam heat load: the current situation of each heat user and the nature of the planned heat load, steam consumption parameter and method, heat consumption method, recovered water situation and the monthly average steam consumption and hours of steam consumption in the last year shall be investigated and obtained, and the maximum, average and minimum hourly steam consumption in winter and summer shall be determined according to the hourly steam consumption of each heat user on typical days in different seasons. For main heat users, the heat load curve for typical days in different seasons and the annual continuous heat load curve shall be drawn.
2) Heating load: heating load is a seasonal heat load, and its change depends on the change of outdoor calculated temperature. The short-term and long-term heating user types within the heating scope shall be obtained, and the heating area and comprehensive heating indicator shall be calculated respectively. The hourly heat load and average heat load in heating period corresponding to each outdoor calculated temperature (from the initial heating temperature to the outdoor calculated heating temperature) are calculated according to the local meteorological data to draw the heating load curve in heating period.
When the heated building is equipped with ventilation and air conditioning heat load, the calculated heating load shall include the heat load for ventilation and air conditioning of the building to heat fresh air.
The selection of heating indicator shall meet the requirements of the current national standard Design code of district heating network.
Note: The initial heating temperature is generally the daily average outdoor temperature +5℃.
The daily average temperature over the years that is not ensured for an average of 5 days in a year shall be adopted as the calculated outdoor heating temperature.
3) Heat load of domestic hot water: hot water load is a year-round load with seasonal variation characteristics. The area of residential and public buildings, heating indicator of domestic hot water, etc. shall be obtained, and the average heat load and maximum heat load of domestic hot water shall be calculated.
4) Condensate recovery: there are many steam users in industrial enterprises, and the loss of steam and water is large. Therefore, condensate shall be recovered as much as possible to reduce the cost of water production. Industrial condensate recovery shall be determined after technical and economic comparison.
5) Prediction of heat load growth: in addition to obtaining and verifying the current heat load data, the expected heat load and the long-term planned heat load must be calculated according to the approved heat consumption of construction projects and the natural growth rate of industrial development, and the scale and final scale of boiler plant construction by stages may be determined accordingly.
3 Cautions for heat load determination:
1) The steam consumption of boiler plant, the loss of steam and water in boiler plant and the loss during heat pipeline transmission shall be considered.
2) Different industrial enterprises have different production shifts, process flows and operation sequences, and the maximum steam consumption cannot occur at the same time, so the simultaneous rate must be included in the heat load statistics.
3) If the main heat load fluctuates greatly, various measures shall be taken to stabilize the heat load, such as arranging a heat accumulator.
4) It is necessary to consider various operating conditions of enterprise heating system and the decrease of heat load after energy-saving technical transformation.
5) For the heat load in winter, the heating indicator shall be comprehensively determined according to the factors such as the calculated outdoor temperature of heating and the types of local buildings and structures specified in specifications.
2.1.2 Calculation of heat load.
1 The maximum, minimum and average heat load and parameters of heat users in different seasons shall be converted into steam supply parameters, steam flow rate or heat supply at boiler plant outlet. It shall be considered that the heating indicator has included 5% heat loss of pipe network when calculating the heating load and domestic hot water heat load according to the heating indicator.
2 When heat loads of heat users are superimposed, the utilization of simultaneous rate shall meet the following requirements:
1) For the main heat users with stable production heat load, on the basis of obtaining their typical daily heat load curves in different seasons, when heat loads are superimposed, the simultaneous rate shall not be calculated.
2) Secondary heat users with small or instable production heat load shall be multiplied by the simultaneous rate when maximum heat loads are superimposed.
3) When the heating load as well as air-conditioning cooling heat load and hot water heat load for living are superimposed, the simultaneous rate shall not be calculated.
2.1.3 Conversion of heat load. Generally, the heat load data obtained varies greatly with the parameters and quantity of heating medium, and must be converted into the parameters and quantity of heating medium at the outlet of boiler plant before comprehensive sorting. The conversion equation is as follows:
Contents of HG/T 20680-2011
Foreword i
1 General principles
2 Heat load in boiler plant and calculation of boiler equipment
2.1 Heat load in boiler plant
2.2 Boiler equipment
3 Calculation of fuel combustion
3.1 Basic requirement
3.2 Sorting out of calculation conditions
3.3 Checking calculation of fuel
3.4 Air consumption for fuel combustion
3.5 Gas out of fuel combustion
3.6 Calculation of fuel consumption
3.7 De-sulfur agent for CFB boiler
3.8 Acid dew point of flue gas
4 Thermal system and calculation of equipment
4.1 Steam/water pipeline
4.2 Deaeration/boiler water supply system and equipment
4.3 Boiler blow-down system and equipment
4.4 Boiler dosing system and equipment
4.5 Desuperheating/decompression system and equipment
4.6 Steam trap/water drainage system
4.7 Industrial water system
4.8 Variable-pressure type steam accumulator
4.9 Steam sub-cylinder
4.10 Steam flasher volume
5 Calculation of flue gas, air system and fan
5.1 Flue gas and air system
5.2 Fan
6 Calculation of pulverized coal preparation system and equipment
6.1 Basic requirement
6.2 Coal mill
6.3 Heat calculation of pulverized coal preparation system
6.4 Aerodynamic calculation of pulverized coal preparation system
6.5 Auxiliary equipment of pulverized coal preparation system
7 Calculation of de-dust and ash/slag system
7.1 De-duster
7.2 De-ash/slag system
8 Calculation of emission of gas pollutant and chimney process
8.1 Basic requirement
8.2 Calculation of emission of chimney pollutant
8.3 Calculation of chimney height
8.4 Calculation and checking of inner diameter of chimney exit
9 Calculation of fuel oil system and equipment for oil-fired boiler
9.1 Supply of fuel oil
9.2 Hydraulic calculation of fuel oil pipeline
9.3 Calculation of intermediate oil chamber
9.4 Calculation of volume of waste oil treatment pond
9.5 Calculation of fuel oil heater
9.6 Calculation of fuel oil filter
9.7 Selection and calculation of oil feed pump and oil supply pump
10 Calculation of fuel gas system and equipment for gas-fired boiler
10.1 General requirements
10.2 Calculation of pressure regulator
10.3 Calculation of fuel gas/liquid knock-out drum
10.4 Hydraulic calculation of fuel gas pipeline
Annex A Local resistance coefficient of flue gas, air and pulverized coal pipeline
Annex B Relationship of combustion features, explosiveness and volatiles of fuel coal
Annex C Relationship between selection of pulverized coal preparation system and coal ignition temperature
Annex D Table of parameters for wheel-type mill series
Annex E Table of parameters for bowl-type mill series
Annex F Table of parameters for ball-ring type mill series
Annex G Table of parameters for S-type mill series
Annex H Diagram of correction coefficient of milling output for S-type fan mill
Annex J Relationship of air humidity and dew point
Annex K Specific heat capacity of gases in average constant pressure
Annex L Maximum flue gas flow velocity and amount at exit of conical chimney under negative and positive pressure
Annex M Maximum flue gas flow velocity and amount at exit of columnar chimney under negative pressure
Annex N Maximum flue gas flow velocity and amount at exit of columnar chimney under zero pressure at inlet
Annex P Structures of chimney and flue gas channel as well as anti-corrosion measures
Explanation of wording in this code