Foreword
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.
According to the requirements of Document JIANBIAO [2011] No.17 issued by the Ministry of Housing and Urban-Rural Development of the People's Republic of China - Notice on printing and distributing the development and revision plan on engineering construction standards and codes in 2011, this code is formulated by China ENFI Engineering Co., Ltd. and China ENFI Engineering Corporation jointly with organizations concerned.
During the preparation of this code, the drafting group conducted extensive and in-depth investigation and research, carefully summarized the design, scientific research, construction and management experience of China's polysilicon industry, widely solicited for opinions, and finalized this code finally through review upon repeated discussions, modifications and improvements.
This code comprises 12 clauses and 3 annexes, with the main contents as follows: general provisions, terms, basic requirements, plant location and planning, process design, electric and automation, utilities, architecture and structure, plumbing and fire protection, HVAC, environmental protection, safety and health, energy saving and waste heat recovery, etc.
The provisions printed in bold type in this code are compulsory 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 compulsory provisions, the Engineering Construction Standard & Specification Management Office of China National Nonferrous Metals Industry Corporation is responsible for the routine management, and China ENFI Engineering Corporation is responsible for the explanation of specific technical contents. During the process of implementing this code, the relevant comments and recommendations, whenever necessary, can be posted or passed on to China ENFI Engineering Corporation (address: No.12, Fuxing Road, Haidian District, Beijing, 100038, China) for reference in future revision.
Contents
1 General provisions 1
2 Terms 2
3 Basic requirements 4
4 Plant location and planning 5
4.1 Plant location 5
4.2 Plant planning 6
5 Process design 9
5.1 General requirements 9
5.2 Trichlorosilane synthesis and silicon tetrachloride hydrogenation 10
5.3 Chlorosilane purification 12
5.4 Trichlorosilane hydrogen reduction 12
5.5 Reduction off-gas recovery by dry method 13
5.6 Filament preparation and polysilicon handling 14
5.7 Analysis and detection 15
6 Electric and automation 17
6.1 Electric 17
6.2 Automation 20
7 Utilities 27
7.1 Compressed air station 27
7.2 Nitrogen production station 27
7.3 Hydrogen production station 28
7.4 Heat transfer oil 28
7.5 Preparation of pure water 28
7.6 Refrigeration station 30
7.7 Steam 31
8 Architecture and structure 33
8.1 General requirements 33
8.2 Main production plant and subsidiary rooms 34
8.3 Fire and explosion protection 37
8.4 Clean design and decoration 39
8.5 Anti-corrosion 40
8.6 Structural design 42
9 Plumbing and fire protection 48
9.1 Water supply 48
9.2 Drainage 48
9.3 Waste water treatment 49
9.4 Circulating cooling water system 50
9.5 Fire protection 50
10 HVAC 51
10.1 General requirements 51
10.2 Ventilation 51
10.3 Air conditioning and cleaning 53
10.4 Smoke control 56
10.5 Cold and heat sources of air conditioning 56
11 Environmental protection, safety and health 59
11.1 Environmental protection 59
11.2 Safety 59
11.3 Health 60
12 Energy saving and waste heat recovery 61
12.1 General requirements 61
12.2 Production process 62
Annex A The minimum horizontal clearance distance between underground pipelines and buildings (structures) 63
Annex B The minimum horizontal clearance distance between underground pipelines 64
Annex C Air cleanliness, temperature and humidity in main rooms 65
Explanation of wording in this code 67
List of quoted standards 68
1 General provisions
1.0.1 This code is formulated with a view to standardizing the engineering design of polysilicon plants, improving the quality of engineering design, and achieving advanced technology, economic rationality, safety and reliability, environmental protection and energy saving.
1.0.2 This code is applicable to the engineering design of the constructed, extended and renovated polysilicon plants using trichlorosilane hydrogen reduction process, and also to the engineering design of trichlorosilane synthesis, silicon tetrachloride hydrogenation and chlorosilane purification in the polysilicon plants using silane disproportionation process.
1.0.3 In the design of polysilicon plants, energy-saving, environmentally friendly, high-efficiency and advanced equipment and processes shall be actively adopted to improve the utilization of resources and energy, and to realize comprehensive utilization of materials and energy and cleaner production.
1.0.4 In addition to this code, the design of polysilicon plants shall also comply with those stipulated in the current relevant standards of the nation.
2 Terms
2.0.1 trichlorosilane hydrogen reduction process
mainstream polysilicon production process that has been continuously improved, in which high-purity trichlorosilane and high-purity hydrogen are introduced into the reduction reactor in a certain proportion, and then undergo reduction or thermal decomposition reaction to produce polysilicon that will deposit and grow on the surface of high-purity filament substrate at about 1,050℃, and moreover the by-products such as hydrogen, hydrogen chloride and silicon tetrachloride and the by-product heat energy produced in this process can be recycled and utilized, thus realizing "internal circulation of materials and comprehensive utilization of energy" to the maximum extent
2.0.2 polysilicon
a form of elemental silicon in which silicon atoms are arranged in a lattice form into many nuclei, the nuclei grow into grains with different crystal orientations, and the grains are combined and crystallized into polysilicon. There are solar-grade polysilicon and semiconductor-grade polysilicon according to their applications
2.0.3 reduction off-gas recovery by dry method
method as opposed to the traditional off-gas recovery process by wet method, which separates the components from off-gas using condensation, absorption, stripping, adhesion and other methods based on the differences in their physical and chemical properties, and then recovers, purifies and returns them to the production system for recycling
2.0.4 silicon tetrachloride hydrogenation
method for processing silicon tetrachloride, a by-product of polysilicon production, by converting to trichlorosilane through reaction with hydrogen
2.0.5 trichlorosilane synthesis
method for producing trichlorosilane, in which trichlorosilane is produced by a chemical reaction between silicon powder and hydrogen chloride in a reactor at a certain temperature
2.0.6 chlorosilane distillation
method for high-purity separation of chlorosilane mixture by realizing mass and heat transfer through gas-liquid exchange
2.0.7 liquid chlorine vaporization
method for heating and evaporating liquid chlorine into chlorine
2.0.8 hydrogen chloride synthesis
method for generating hydrogen chloride gas from hydrogen and chlorine through chemical reaction
2.0.9 hydrochloric acid stripping
method for stripping hydrogen chloride from hydrochloric acid
2.0.10 reduction reactor
special equipment for producing rod-shaped polysilicon
2.0.11 inverse disproportionating of dichlorosilane
method for recycling dichlorosilane by converting dichlorosilane and silicon tetrachloride into trichlorosilane through chemical reaction
2.0.12 polysilicon handling
general term for further treatment of polysilicon after being discharged according to the requirements of customers and product analysis and detection, including cutting head and tail, drilling rod, rounding, crushing, sorting, weighing, corrosion cleaning, drying and packaging
2.0.13 chlorosilane
general term for the substances formed after the hydrogen atoms in silane (SiH4) are partially or completely replaced by chlorine atoms, usually including silicon tetrachloride (SiCl4), trichlorosilane (SiHCl3), dichlorosilane (SiH2Cl2) and chlorosilane (SiH3Cl)
2.0.14 reduction off-gas
mixed gas of the raw materials not involved in reaction and the by-products generated during reaction in the process of producing polysilicon in reduction reactor, mainly including hydrogen, gaseous chlorosilane and hydrogen chloride
2.0.15 explosion-proof protective wall
partition wall with a certain explosion-proof capability that is able to prevent injury to facilities and personnel from flying debris generated by explosions
3 Basic requirements
3.0.1 The design scale of solar-grade polysilicon plant shall meet the requirements of the current codes of the nation on photovoltaic manufacturing industry.
3.0.2 The polysilicon plant shall be equipped with advanced process technology, energy-saving and environmentally friendly process equipment and safety facilities meeting the requirements of the current codes of the nation on photovoltaic manufacturing industry.
3.0.3 The design of polysilicon plant shall meet the requirements of current national standard GB 29447 The norm of energy consumption per unit products of polysilicon enterprise and other regulations on safety, environmental protection, energy saving, fire protection and labor health.
1 General provisions
2 Terms
3 Basic requirements
4 Plant location and planning
4.1 Plant location
4.2 Plant planning
5 Process design
5.1 General requirements
5.2 Trichlorosilane synthesis and silicon tetrachloride hydrogenation
5.3 Chlorosilane purification
5.4 Trichlorosilane hydrogen reduction
5.5 Reduction off-gas recovery by dry method
5.6 Filament preparation and polysilicon handling
5.7 Analysis and detection
6 Electric and automation
6.1 Electric
6.2 Automation
7 Utilities
7.1 Compressed air station
7.2 Nitrogen production station
7.3 Hydrogen production station
7.4 Heat transfer oil
7.5 Preparation of pure water
7.6 Refrigeration station
7.7 Steam
8 Architecture and structure
8.1 General requirements
8.2 Main production plant and subsidiary rooms
8.3 Fire and explosion protection
8.4 Clean design and decoration
8.5 Anti-corrosion
8.6 Structural design
9 Plumbing and fire protection
9.1 Water supply
9.2 Drainage
9.3 Waste water treatment
9.4 Circulating cooling water system
9.5 Fire protection
10 HVAC
10.1 General requirements
10.2 Ventilation
10.3 Air conditioning and cleaning
10.4 Smoke control
10.5 Cold and heat sources of air conditioning
11 Environmental protection, safety and health
11.1 Environmental protection
11.2 Safety
11.3 Health
12 Energy saving and waste heat recovery
12.1 General requirements
12.2 Production process
Annex A The minimum horizontal clearance distance between underground pipelines and buildings (structures)
Annex B The minimum horizontal clearance distance between underground pipelines
Annex C Air cleanliness, temperature and humidity in main rooms
Explanation of wording in this code
List of quoted standards
