Technology standard for backfill engineering in metallic and non-metallic mines
1 General provisions
1.0.1 This standard is formulated in order to standardize the engineering design, production operation and quality inspection for mine backfill, improve the technical level of domestic mine backfill, and promote the popularization and application of backfill mining method.
1.0.2 This standard is applicable to the engineering design, production operation and quality inspection for metallic and non-metallic underground mine backfill.
1.0.3 In addition to this standard, the design of metallic and non-metallic mine backfill shall also comply with the current relevant standards of the nation.
2 Terms
2.0.1
mine backfill
operation process of underground goaf backfill be means of sand, stone and other materials
2.0.2
backfill material
include backfill aggregate, binder and water as well as additives to improve the performance of backfill slurry
2.0.3
backfill aggregate
inert material that play a function of back-filling and supporting in a backfill
2.0.4
tailings
solid waste discharged by a concentrator after it grinds fine the ore and selects useful components under the current technical conditions
2.0.5
unclassified tailings
ungraded full-size tailings
2.0.6
classified tailings
coarse-grained sedimented sand used for mine backfill after tailings classification
2.0.7
particle size distribution
proportion of the particle content of each grade of the material to the total material, usually expressed as a percentage.
2.0.8
binder
material that can change from slurry to solid stone-like body and cement other materials to form a composite solid substance with certain mechanical strength under the physical and chemical action
2.0.9
backfill slurry
slurry formed by backfill aggregate, binder, etc. with water
2.0.10
recipe of backfill slurry
mass proportion relationship between backfill materials in backfill slurry
2.0.11
solid content of backfill slurry
percentage of dry mass of backfill aggregate and binder to the total mass of backfill slurry
2.0.12
settling ratio of backfill slurry
ratio of the volume of backfill slurry to the volume of coagulated and solidified backfill
2.0.13
backfill
solid or granular material formed by dehydration, solidification and hardening of backfill materials.
2.0.14
stope backfill
backfill formed after the backfill materials enter underground goaf such as stope
2.0.15
backfill specimen
backfill sample obtained by casting or core drilling for the purposes of testing or quality inspection
2.0.16
backfill strength
ultimate stress of a backfill to keep itself from being destroyed when resisting external force
2.0.17
backfill system
general term for equipment, facilities and structures used for collecting, processing and storing backfill materials, preparing backfill slurry and transporting them to a goaf
2.0.18
cemented backfill
mine backfill method that can harden backfill slurry (with binder in backfill materials) and have certain strength
2.0.19
uncemented backfill
mine backfill method that can consolidate or accumulate backfill materials (without binder in backfill materials)
2.0.20
hydraulic backfill
backfill method that takes water as a conveying carrier to turn the backfill materials in the state of two-phase fluid and then transport them to a goaf by pipelines
2.0.21
paste backfill
backfill method that backfill materials are transported to a goaf by pipelines in the state of structural fluid without setting up a dehydration facility in the goaf
2.0.22
rock backfill
backfill method that mine excavation waste rock or broken waste rock is taken as backfill material to refill the goaf
3 Backfill material
3.1 General requirements
3.1.1 Filling material shall meet the requirements of environmental protection and safety in China without producing harmful effects on human body, environment and backfill performance.
3.1.2 The backfill aggregate shall be selected according to the following requirements:
1 Backfill aggregate shall comply with the relevant provisions of the current national standard GB 18599 Standard for pollution control on the non-hazardous industrial solid waste storage and landfill;
2 Backfill aggregate shall be mine solid waste such as tailings, waste rock or non-hazardous industrial solid waste;
3 Aggregate with sulfur content exceeding 8% shall not be used for cemented backfill.
3.1.3 Cement or other materials with cementitious effect shall be used as binders.
3.1.4 The quality of water for backfill shall meet the following requirements:
1 pH value shall not be less than 5.
2 The content of SO_4^(2-) shall not exceed 2,700 mg/L.
3.1.5 Before the preliminary design of the backfill system construction scheme, the backfill material test shall be completed.
3.1.6 If changes occur in the backfill material or its properties, the corresponding backfill material test shall be carried out again.
3.2 Sampling of backfill material
3.2.1 Specimens of backfill materials shall be representative.
3.2.2 The tailings produced by continuous selection test shall be selected for the mine which adopts tailings backfill but its concentrator has not yet been built.
3.2.3 Chessboard sampling shall be adopted for bulk aggregate.
3.2.4 The sampling quantity of backfill materials shall be greater than 1.5 times of the amount required for the test.
3.2.5 Binders shall be moisture-proof during laboratory storage and shall be used within the shelf life.
3.3 Preparation of laboratory backfill material
3.3.1 The tailings mortar shall be air-dried naturally, mixed evenly by ring cone method, cone moving method or rolling method, and packaged in batches according to the test scheme.
3.3.2 Before the test, the moisture content of backfill aggregate shall be measured, and the recipe of backfill slurry shall be calculated based on the moisture content of backfill aggregate.
3.3.3 When mixing backfill materials in laboratory, the material amount shall be measured by mass. During weighing, the allowable deviation of aggregate is ±0.5%, and that of binder, water and additives is ±0.2%.
3.3.4 Mechanical stirring shall be adopted for laboratory backfill slurry, with the stirring time of not be less than 180 s.
3.4 Aggregate physical and chemical tests
3.4.1 The test parameters of physical properties of aggregate shall include density, particle size, porosity and permeability coefficient, and the test method shall be implemented according to the relevant provisions of the current national standard GB/T 50123 Standard for geotechnical testing method.
3.4.2 Aggregate shall be tested for its chemical composition and content.
3.4.3 Test for aggregate particle size distribution shall meet the following requirements:
1 Aggregate with particle size greater than 74 μm shall adopt the screening test method.
2 Aggregate with particle size less than or equal to 74 μm shall adopt laser particle size analysis test method, wet sieve method and hydraulic analysis method.
3.5 Binder test
3.5.1 The water requirement of normal consistency, setting time and soundness of binders shall be carried out according to the relevant provisions of the current national standard GB/T 1346 Test methods for water requirement of normal consistency, setting time and soundness of the portland cement.
3.5.2 Cement strength test shall be carried out according to the relevant provisions of the current national standard GB/T 17671 Method of testing cements — Determination of strength.
3.6 Tailings settling test
3.6.1 Tailings settling test shall be carried out for the backfill process of preparing tailings mortar by gravity settling concentration.
3.6.2 Static simple settling test shall be carried out for classified tailings backfill, and settling velocity, solid flux and maximum underflow concentration under different feed concentrations shall be recorded.
3.6.3 Static simple settling test and static flocculent settling test shall be carried out for unclassified tailings backfill. Dynamic flocculent settling test shall be carried out for the concentration by a deep cone thickener as supplement, and settling velocity, solid flux, maximum underflow concentration and suspended solids concentration in overflow water shall be recorded under different feed concentrations, different flocculants and different addition amount of the same flocculant.
3.6.4 Tailings settling test shall be carried out according to Annex A of this standard.
1 General Provisions
2 Terminology
3 Filling materials
4 Filling system design
5 Filling operations
6 Quality Inspection
Appendix A Settlement test of tailing sand
Appendix B Fill slurry expansion test
Appendix C filling sinkage ratio test
Appendix D Calculation of filling material consumption
Glossary of this standard
Standard
GB/T 51450-2022 Technology standard for backfill engineering in metallic and non-metallic mines (English Version)
Standard No.
GB/T 51450-2022
Status
valid
Language
English
File Format
PDF
Word Count
16500 words
Price(USD)
495.0
Implemented on
2022-12-1
Delivery
via email in 1~5 business day
Detail of GB/T 51450-2022
Standard No.
GB/T 51450-2022
English Name
Technology standard for backfill engineering in metallic and non-metallic mines
Technology standard for backfill engineering in metallic and non-metallic mines
1 General provisions
1.0.1 This standard is formulated in order to standardize the engineering design, production operation and quality inspection for mine backfill, improve the technical level of domestic mine backfill, and promote the popularization and application of backfill mining method.
1.0.2 This standard is applicable to the engineering design, production operation and quality inspection for metallic and non-metallic underground mine backfill.
1.0.3 In addition to this standard, the design of metallic and non-metallic mine backfill shall also comply with the current relevant standards of the nation.
2 Terms
2.0.1
mine backfill
operation process of underground goaf backfill be means of sand, stone and other materials
2.0.2
backfill material
include backfill aggregate, binder and water as well as additives to improve the performance of backfill slurry
2.0.3
backfill aggregate
inert material that play a function of back-filling and supporting in a backfill
2.0.4
tailings
solid waste discharged by a concentrator after it grinds fine the ore and selects useful components under the current technical conditions
2.0.5
unclassified tailings
ungraded full-size tailings
2.0.6
classified tailings
coarse-grained sedimented sand used for mine backfill after tailings classification
2.0.7
particle size distribution
proportion of the particle content of each grade of the material to the total material, usually expressed as a percentage.
2.0.8
binder
material that can change from slurry to solid stone-like body and cement other materials to form a composite solid substance with certain mechanical strength under the physical and chemical action
2.0.9
backfill slurry
slurry formed by backfill aggregate, binder, etc. with water
2.0.10
recipe of backfill slurry
mass proportion relationship between backfill materials in backfill slurry
2.0.11
solid content of backfill slurry
percentage of dry mass of backfill aggregate and binder to the total mass of backfill slurry
2.0.12
settling ratio of backfill slurry
ratio of the volume of backfill slurry to the volume of coagulated and solidified backfill
2.0.13
backfill
solid or granular material formed by dehydration, solidification and hardening of backfill materials.
2.0.14
stope backfill
backfill formed after the backfill materials enter underground goaf such as stope
2.0.15
backfill specimen
backfill sample obtained by casting or core drilling for the purposes of testing or quality inspection
2.0.16
backfill strength
ultimate stress of a backfill to keep itself from being destroyed when resisting external force
2.0.17
backfill system
general term for equipment, facilities and structures used for collecting, processing and storing backfill materials, preparing backfill slurry and transporting them to a goaf
2.0.18
cemented backfill
mine backfill method that can harden backfill slurry (with binder in backfill materials) and have certain strength
2.0.19
uncemented backfill
mine backfill method that can consolidate or accumulate backfill materials (without binder in backfill materials)
2.0.20
hydraulic backfill
backfill method that takes water as a conveying carrier to turn the backfill materials in the state of two-phase fluid and then transport them to a goaf by pipelines
2.0.21
paste backfill
backfill method that backfill materials are transported to a goaf by pipelines in the state of structural fluid without setting up a dehydration facility in the goaf
2.0.22
rock backfill
backfill method that mine excavation waste rock or broken waste rock is taken as backfill material to refill the goaf
3 Backfill material
3.1 General requirements
3.1.1 Filling material shall meet the requirements of environmental protection and safety in China without producing harmful effects on human body, environment and backfill performance.
3.1.2 The backfill aggregate shall be selected according to the following requirements:
1 Backfill aggregate shall comply with the relevant provisions of the current national standard GB 18599 Standard for pollution control on the non-hazardous industrial solid waste storage and landfill;
2 Backfill aggregate shall be mine solid waste such as tailings, waste rock or non-hazardous industrial solid waste;
3 Aggregate with sulfur content exceeding 8% shall not be used for cemented backfill.
3.1.3 Cement or other materials with cementitious effect shall be used as binders.
3.1.4 The quality of water for backfill shall meet the following requirements:
1 pH value shall not be less than 5.
2 The content of SO_4^(2-) shall not exceed 2,700 mg/L.
3.1.5 Before the preliminary design of the backfill system construction scheme, the backfill material test shall be completed.
3.1.6 If changes occur in the backfill material or its properties, the corresponding backfill material test shall be carried out again.
3.2 Sampling of backfill material
3.2.1 Specimens of backfill materials shall be representative.
3.2.2 The tailings produced by continuous selection test shall be selected for the mine which adopts tailings backfill but its concentrator has not yet been built.
3.2.3 Chessboard sampling shall be adopted for bulk aggregate.
3.2.4 The sampling quantity of backfill materials shall be greater than 1.5 times of the amount required for the test.
3.2.5 Binders shall be moisture-proof during laboratory storage and shall be used within the shelf life.
3.3 Preparation of laboratory backfill material
3.3.1 The tailings mortar shall be air-dried naturally, mixed evenly by ring cone method, cone moving method or rolling method, and packaged in batches according to the test scheme.
3.3.2 Before the test, the moisture content of backfill aggregate shall be measured, and the recipe of backfill slurry shall be calculated based on the moisture content of backfill aggregate.
3.3.3 When mixing backfill materials in laboratory, the material amount shall be measured by mass. During weighing, the allowable deviation of aggregate is ±0.5%, and that of binder, water and additives is ±0.2%.
3.3.4 Mechanical stirring shall be adopted for laboratory backfill slurry, with the stirring time of not be less than 180 s.
3.4 Aggregate physical and chemical tests
3.4.1 The test parameters of physical properties of aggregate shall include density, particle size, porosity and permeability coefficient, and the test method shall be implemented according to the relevant provisions of the current national standard GB/T 50123 Standard for geotechnical testing method.
3.4.2 Aggregate shall be tested for its chemical composition and content.
3.4.3 Test for aggregate particle size distribution shall meet the following requirements:
1 Aggregate with particle size greater than 74 μm shall adopt the screening test method.
2 Aggregate with particle size less than or equal to 74 μm shall adopt laser particle size analysis test method, wet sieve method and hydraulic analysis method.
3.5 Binder test
3.5.1 The water requirement of normal consistency, setting time and soundness of binders shall be carried out according to the relevant provisions of the current national standard GB/T 1346 Test methods for water requirement of normal consistency, setting time and soundness of the portland cement.
3.5.2 Cement strength test shall be carried out according to the relevant provisions of the current national standard GB/T 17671 Method of testing cements — Determination of strength.
3.6 Tailings settling test
3.6.1 Tailings settling test shall be carried out for the backfill process of preparing tailings mortar by gravity settling concentration.
3.6.2 Static simple settling test shall be carried out for classified tailings backfill, and settling velocity, solid flux and maximum underflow concentration under different feed concentrations shall be recorded.
3.6.3 Static simple settling test and static flocculent settling test shall be carried out for unclassified tailings backfill. Dynamic flocculent settling test shall be carried out for the concentration by a deep cone thickener as supplement, and settling velocity, solid flux, maximum underflow concentration and suspended solids concentration in overflow water shall be recorded under different feed concentrations, different flocculants and different addition amount of the same flocculant.
3.6.4 Tailings settling test shall be carried out according to Annex A of this standard.
Contents of GB/T 51450-2022
1 General Provisions
2 Terminology
3 Filling materials
4 Filling system design
5 Filling operations
6 Quality Inspection
Appendix A Settlement test of tailing sand
Appendix B Fill slurry expansion test
Appendix C filling sinkage ratio test
Appendix D Calculation of filling material consumption
Glossary of this standard
