Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This code is formulated by China National Textile and Apparel Council and China Kunlun Contracting & Engineering Co. Ltd. jointly with organizations concerned according to the requirements of "Notice on Printing and Distributing the Development and Revision Plan of National Engineering Construction Standards and Codes in 2014" (JIANBIAO [2013] No.169) issued by the Ministry of Housing and Urban-Rural Development.
During the formulation process, the code drafting group has carried out extensive investigation and study, summarized the construction experience of PTA plants in China over the years, especially the experience and lessons on design and construction of PTA plant with continuously expanding production scale and rapidly developing localized technology of PTA plant in recent years, and widely solicited for opinions on aspects such as production and construction, and then finalized this code through review.
This code consists of 16 chapters and 1 annex, with specific technical contents covering: general provisions, terms, process design, process equipment, general layout design, equipment layout, process pipeline design, auxiliary production facilities, automatic control and instruments, electrical and telecommunication, building, structure, water supply and drainage, fire-fighting, occupational health and safety, environmental protection, etc.
In this code, the provisions printed in bold type are mandatory and must be enforced strictly.
The Ministry of Housing and Urban-Rural Development is in charge of the administration of this code and the explanation of the mandatory provisions, China National Textile and Apparel Council is responsible for routine management and China Kunlun Contracting & Engineering Co. Ltd. is responsible for the explanation of specific technical contents. All relevant organizations are kindly requested to carefully sum up experience in combination with engineering practices when implementing this code. The relevant modification and supplement, whenever necessary, should be fed back to China Kunlun Contracting & Engineering Co. Ltd. (address: No. 21 Zengguang Road, Haidian District, Beijing; 100037) for reference in future revision.
Contents
Foreword i
1 General Provisions 1
2 Terms 2
3 Process Design 4
3.1 General Requirements 4
3.2 Process Flow Design 5
3.3 Process Calculation 6
3.4 Hazard Factors 7
3.5 Safety Relief System 7
3.6 Insulation and Heat Tracing 8
4 Process Equipment 9
4.1 Equipment Type Selection 9
4.2 Equipment Material Selection 9
4.3 Equipment Structure Design 11
4.4 Selection of Equipment Design Parameter 11
4.5 Manufacture and Examination of Equipment 12
5 General Layout Design 15
6 Equipment Layout 17
6.1 Principles of Equipment Layout 17
6.2 Requirements of Equipment Layout 17
7 Process Pipeline Design 19
7.1 Pipeline Layout 19
7.2 Pipe Material Selection 19
7.3 Pipeline Flexibility Design 20
7.4 Pipeline Examination and Pressure Test 21
8 Auxiliary Production Facilities 23
8.1 Product Storehouse 23
8.2 Tank Farm 23
9 Automatic Control and Instruments 25
9.1 Automation Level 25
9.2 Main Control Strategies 25
9.3 Selection of Instruments and Control Valves 26
9.4 Control System Configuration 27
9.5 Control Room 28
9.6 Interlock Protection 29
9.7 Safety Measures for Instrument 30
10 Electrical and Telecommunication 32
10.1 General Requirements 32
10.2 Power Supply and Distribution 32
10.3 Lighting 34
10.4 Lightening Protection 35
10.5 Earthing 35
10.6 Automatic Fire Alarm System 36
10.7 Telecommunication 36
11 Building 37
11.1 General Requirements 37
11.2 Building Design 37
11.3 Fire, Explosion and Corrosion Prevention 38
12 Structure 40
12.1 General Requirements 40
12.2 Design Load 40
12.3 Structure Design 41
13 Water Supply and Drainage 44
13.1 Water Supply 44
13.2 Water Drainage 44
13.3 Pipeline of Water Supply and Drainage 45
14 Firefighting 47
15 Occupational Health and Safety 49
15.1 General Requirements 49
15.2 Fire and Explosion Prevention 49
15.3 Dust, Radiation Protection and Anticorrosive 49
15.4 Fall, Mechanical Injury Protection and Burn-proof Insulation 50
15.5 Safety Signs and Colors 50
15.6 Occupational Health Protection 51
15.7 Emergency Rescue 51
16 Environmental Protection 52
16.1 General Requirements 52
16.2 Waste Gas Treatment 52
16.3 Waste Water Treatment 52
16.4 Solid Waste Treatment 52
16.5 Noise Control 53
16.6 Measures for Prevention and Control of Water Pollution 53
Annex A Requirements of Explosion Hazards Classification for PTA Plant 55
Explanation of Wording in this Code 58
List of Quoted Standards 59
Code for Design of PTA Plant
1 General Provisions
1.0.1 This code is formulated with a view to unifying the technical requirements for design of PTA plant, improving the design level of PTA plant and realizing technical advancement, safety and environmental protection, energy conservation and consumption reduction, economy and rationality.
1.0.2 This code is applicable to the design of the newly-constructed, extended and reconstructed engineering, excluding the utilities and office facilities used for PTA plant.
1.0.3 The design of PTA plant shall not only meet the requirements stipulated in this code, but also comply with those in the current relevant ones of the nation.
2 Terms
2.0.1 plant for production of purified terephthalic acid (PTA plant)
the plant producing acceptable industrial purified terephthalic acid products through oxidation reaction and purification reaction with p-xylene and air as raw materials. PTA plant is mainly composed of production device and auxiliary production facilities; the production device mainly includes oxidation unit and purification unit while the auxiliary production facilities mainly include product storehouse and tank farm
2.0.2 oxidation reaction
the process generating crude terephthalic acid through reaction with p-xylene and air as raw materials, acetic acid as solvent, cobalt and manganese as catalyzer and bromine as accelerant
2.0.3 purification reaction
the process of obtaining purified terephthalic acid through separation and drying after reducing the impurity carboxybenzaldehyde (4-CBA) in crude terephthalic acid to p-toluic acid (p-T acid) with crude terephthalic acid and hydrogen as raw materials and palladium/carbon as catalyzer
2.0.4 crude terephthalic acid (CTA)
the product of oxidation unit, also the raw material of downstream purification unit
2.0.5 purified terephthalic acid (PTA)
the product of purification unit, also the product of PTA plant
2.0.6 oxidation off gas
the gas-phase product of oxidation reaction
2.0.7 entrainer
the substance added during solvent recovery to form azeotrope with water, thereby separating the acetic acid and water mixture. Entrainer refers to common n-propyl acetate, n-butyl acetate or isobutyl acetate in this code
2.0.8 slurry
the non-separated solid-liquid mixture containing CTA or PTA suspending particles
2.0.9 mother liquor
the filtrate after slurry separation
2.0.10 pressure filtration
the process realizing solid-liquid separation under certain positive pressure
2.0.11 drying
the dehumidifying and drying process of wet filter cake after slurry filtration
3 Process Design
3.1 General Requirements
3.1.1 The process design of PTA plant shall meet the requirements of technical advancement, safety and reliability, energy conservation and environmental protection as well as economy and rationality.
3.1.2 The process design shall be based on the data of material balance and energy balance.
3.1.3 The comprehensive energy consumption index of newly-constructed, reconstructed or extended PTA plant shall meet the relevant requirements of the current national standard GB 31533 The Norm of Energy Consumption per Unit Product of Pure Terephthalic Acid.
3.1.4 The design annual operation time of PTA plant should be calculated as 8000h.
3.1.5 Washing facilities shall be arranged for the slurry pipeline between reactor and crystallizer.
3.1.6 Inert gas replacement facilities shall be arranged for the equipment and pipelines containing p-xylene, acetic acid, entrainer, methyl acetate and hydrogen.
3.1.7 Check valve shall be arranged at pump outlet pipeline delivering p-xylene, acetic acid, entrainer and methyl acetate.
3.1.8 Two drain valves shall be arranged at the low point of hydrogen pipeline; for the drain valves which may only be used at commencement and shutdown, a valve equipped with flange cover may be arranged.
3.1.9 The washing design of slurry pipeline shall meet the following requirements:
1 Check valve shall be arranged at the continuously used washing acid or process water pipeline, and block valve shall be arranged at the root of such pipeline.
2 Check valve and two block valves shall be arranged at the intermittently used washing acid, process water, alkali liquor and demineralized water pipelines, and drain valve shall be arranged at the low point between two block valves.
3 Blind plate or disconnection from the system shall be arranged for the alkali liquor pipeline used only upon equipment shutdown.
3.1.10 Isolating valve and 8-shaped blind plate shall be arranged for the pipeline delivering p-xylene, acetic acid, entrainer and hydrogen entering into the production device at the device boundary.
3.1.11 Metering instruments shall be arranged for various raw materials and utility media.
3.1.12 Sampling port shall be arranged respectively at the inlet and outlet pipelines of oxidation off gas purification system.
3.1.13 Sampling port shall be arranged at the exhaust funnel of oxidation off gas after purification treatment. The sampling port shall be of circular structure with nominal diameter of DN80~DN100.
3.1.14 Closed sampling shall be adopted for combustible liquids such as p-xylene, acetic acid, methyl acetate and entrainer.
3.1.15 Automatic sampler and manual sampling port should be simultaneously arranged on the pipeline delivering CTA and PTA powders.
3.2 Process Flow Design
3.2.1 The process flow shall be determined according to production scale, product scheme and product quality requirements.
3.2.2 The process flow shall meet the principles of advanced and mature technology, low material and energy consumption and less discharge of "three-waste".
3.2.3 The process flow design of oxidation unit shall meet the following requirements:
1 The oxidation off gas shall only be discharged after reaching the standard through purification and energy recovery;
2 The gas of atmospheric pressure system shall only be discharged after reaching the standard through purification treatment;
3 Pressure filtration process should be adopted for separation of CTA slurry;
4 Solvent recovery system shall be arranged, and the water separated by this system shall be recycled;
5 CTA, acetic acid, cobalt and manganese recovery system shall be arranged for the extracted oxidation mother liquor;
6 Oxidation mother liquor tank shall be arranged, and its capacity shall be able to contain the returned mother liquor of the system upon shutdown.
3.2.4 The process flow design of purification unit shall meet the following requirements:
1 Flash steam of crystallization system and its heat quantity shall be recycled;
2 A pass of pressure filtration process should be adopted;
3 Pneumatic conveying should be adopted for CTA and PTA powders;
4 PTA, cobalt and manganese recovery system shall be arranged for the purified mother liquor.
3.2.5 Slurry filter shall be arranged according to the processing capacity calculation of single equipment, and standby set shall be arranged based on the cleaning period and fault frequency of filter.
3.2.6 The steam system should be recycled according to the target temperature of the heated medium and the level of byproduct steam of device through level-by-level flashing of condensate.
3.2.7 The supply and return of the circulating cooling water shall be designed according to the resistance drop of equipment and pipeline and the difference of equipment installation height based on different pressures and systems.
3.3 Process Calculation
3.3.1 The whole process shall be subject to material balance and energy balance calculation.
3.3.2 The utility consumption of each equipment in production device shall be calculated.
3.3.3 The process calculation of non-stereotype equipment in production device shall be carried out according to logistic data and purpose.
3.3.4 Type selection of stereotype equipment in production device shall be determined according to the medium characteristic, operating parameter and arrangement quantity calculation.
3.3.5 The diameter and resistance drop of pipeline shall be determined through calculation, and should be implemented in accordance with the current professional standard SH/T 3035 Guide for Pipeline Sizing in Petrochemical Engineering.
3.3.6 The type selection of safety valve, rupture disk, breather valve, silencer and steam trap shall be determined according to the calculation based on different operating conditions.
3.3.7 The thermal insulation thickness of equipment and pipeline shall be determined through calculation.
Foreword i
1 General Provisions
2 Terms
3 Process Design
3.1 General Requirements
3.2 Process Flow Design
3.3 Process Calculation
3.4 Hazard Factors
3.5 Safety Relief System
3.6 Insulation and Heat Tracing
4 Process Equipment
4.1 Equipment Type Selection
4.2 Equipment Material Selection
4.3 Equipment Structure Design
4.4 Selection of Equipment Design Parameter
4.5 Manufacture and Examination of Equipment
5 General Layout Design
6 Equipment Layout
6.1 Principles of Equipment Layout
6.2 Requirements of Equipment Layout
7 Process Pipeline Design
7.1 Pipeline Layout
7.2 Pipe Material Selection
7.3 Pipeline Flexibility Design
7.4 Pipeline Examination and Pressure Test
8 Auxiliary Production Facilities
8.1 Product Storehouse
8.2 Tank Farm
9 Automatic Control and Instruments
9.1 Automation Level
9.2 Main Control Strategies
9.3 Selection of Instruments and Control Valves
9.4 Control System Configuration
9.5 Control Room
9.6 Interlock Protection
9.7 Safety Measures for Instrument
10 Electrical and Telecommunication
10.1 General Requirements
10.2 Power Supply and Distribution
10.3 Lighting
10.4 Lightening Protection
10.5 Earthing
10.6 Automatic Fire Alarm System
10.7 Telecommunication
11 Building
11.1 General Requirements
11.2 Building Design
11.3 Fire, Explosion and Corrosion Prevention
12 Structure
12.1 General Requirements
12.2 Design Load
12.3 Structure Design
13 Water Supply and Drainage
13.1 Water Supply
13.2 Water Drainage
13.3 Pipeline of Water Supply and Drainage
14 Firefighting
15 Occupational Health and Safety
15.1 General Requirements
15.2 Fire and Explosion Prevention
15.3 Dust, Radiation Protection and Anticorrosive
15.4 Fall, Mechanical Injury Protection and Burn-proof Insulation
15.5 Safety Signs and Colors
15.6 Occupational Health Protection
15.7 Emergency Rescue
16 Environmental Protection
16.1 General Requirements
16.2 Waste Gas Treatment
16.3 Waste Water Treatment
16.4 Solid Waste Treatment
16.5 Noise Control
16.6 Measures for Prevention and Control of Water Pollution
Annex A Requirements of Explosion Hazards Classification for PTA Plant
Explanation of Wording in this Code
List of Quoted Standards
