2015 UTAH ASPHALT CONFERENCE AGGREGATE PRODUCTION 101. Kilgore Companies and Kimball Equipment

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1 2015 UTAH ASPHALT CONFERENCE AGGREGATE PRODUCTION 101 Kilgore Companies and Kimball Equipment

2 Table of Contents Types of Aggregates used in Asphalt Production Extraction Processes Primary Crushing Secondary and Tertiary Crushing Screening Equipment Screen Cloth Material Handling Material Load Out Aggflow Questions 2

3 Types of Aggregates used in Asphalt Sand and Gravel Sand has the fine debris of rocks, consisting of small loose grains, often consisting of quartz Gravel has small to large pieces of rock and stone. 3

4 Types of Aggregates used in Asphalt Limestone A sedimentary rock consisting primarily of calcium carbonate, often in the form of the mineral calcite. Limestone can occur in many colors but are usually white, gray, or black. They often contain fossil shells and other marine organisms 4

5 Types of Aggregates used in Asphalt Granite A common, coarse-grained, light-colored, hard igneous rock Great hardness, firmness, or durability Trap Rock is any dark-colored, fine-grained, igneous rock 5

6 Aggregate Extraction Processes Extraction The vast majority of materials used in the mineral aggregate industry are obtained from surface-mined stone quarries or from sand and gravel pits. How materials are extracted influences their quality. 6

7 Aggregate Extraction Processes Stripping As a first step, a Producer is required to designate a detailed stripping procedure for each and every deposit that is mined. This phase often is overlooked, yet has a great influence on the quality and variability of the product. Inadequate removal of overburden from the mineral deposit often may be the source of excessive variation in minus No. 200 material. 7

8 Aggregate Extraction Process Drilling and Blasting Quarry operators commonly design fragmentation shots for safety and ease of use at the primary crusher. The shot layout is required to be properly engineered, documented, and adhered to for maximum consistency. Varying the shot pattern may mean changes in product size throughout the operation. Smaller shot rock, resulting in less crushing in the secondary and tertiary stages, may mean less improvement through crushing. This can result in quality issues. 8

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11 Aggregate Extraction Processes Gravel Bank Extraction 11

12 Material Considerations Factors Affecting Crushing Process Material to be Crushed (what is available) Finished Product Size (desired product sizes) Desired Capacity (expected production rates) Wear Costs (material characteristic)

13 Material Considerations Factors Affecting Crusher Type Type of Material (abrasiveness) Compressive Strength Hardness of Material 25 (friability) Density (toughness) Fragmentation (particle shape) Material Condition (Clay or Dirt)

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32 Flow circuit for MAX Production Non-Selective Circuit Material from primary jaw and secondary cone is mixed with material from tertiary cone TPH for Max Production Rate Red lines indicate slabby material

33 Crushing Reduction Ratios Jaw.. 6 to 1 Cone (SH)....6 to 1 Cone (FH)....4 to 1 V.S.I. (Gravels & Basalts) 6-8 to 1 V.S.I. (Limestones).8-10 to 1 H.S.I to 1 Hammermill.. 20 to 1 Limemill.. 30 to 1 Note: The reduction ratio may vary by shape and friability of feed. Reduction ratios shown are for optimum production and gradation.

34 Abrasive Effect Abrasives Binding Agents Silica dioxide (SiO 2 ) Calcium carbonate (CaCO 3 ) Iron oxide (Fe 2 O 3 ) Magnesium carbonate (MgCO 3 ) Aluminum Oxide (Al 2 O 3 ) Total abrasives is the sum of Silica Dioxide (SiO 2 ), Iron Oxide (Fe 2 O 3 ) and Aluminum Oxide (Al 2 O 3 ). The Magnesium Carbonate (MgCO 3 ) content must also be considered. Each 5-10% of MgCO 3 will result in wear similar to 1% of additional total abrasives.

35 Abrasive Content Limit Recommended Abrasive Content Limitations 3% Limemill 5% Hammermill 10% Single Impeller 15% Double Impeller 50% Horizontal Rotor Secondary (High-Chrome) 70% Vertical Shaft Impactor (High-Chrome) 100% Compression Type (Jaw, Rolls, Cones)

36 Primary Crushing Equipment Jaw Crusher Horizontal Shaft Impactor Gyratory Crusher 36

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40 HSI Secondary Impact Crusher HORIZONTAL SHAFT IMPACT CRUSHER

41 Horizontal Impact Crusher Type of Crusher -The HSI is an impact crusher. The material is crushed by it s impact with the rotor blowbars and further broken as it impact the breaker plates. Application -The application is typically as a secondary and sometimes a primary in soft to medium hard materials. Reduction Ratio -The expected reduction ratio is 6 to 12:1. Particle Shape -The HSI provides quality output no matter what the feed rate. The HSI is an excellent tool for quality concrete aggregates. Fine Production -A HSI promotes fines production. Crushed Faces -The HSI provides a high % crushed faces.

42 Factors Affecting HSI Crusher Performance Speed Curtain setting Blowbar penetration Inertia Power Blowbar metallurgy Expansion chambers Proper feed angle Impeller bar quantity

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44 Gyratory Crusher 44

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47 Secondary and Tertiary Crushing HORIZONTAL SHAFT IMPACT CRUSHER 47

48 Secondary and Tertiary Crushing Type of Crusher -The HSI is an impact crusher. The material is crushed by it s impact with the rotor blowbars and further broken as it impact the breaker plates. Application -The application is typically as a secondary and sometimes a primary in soft to medium hard materials. Particle Shape -The HSI provides quality output no matter what the feed rate. The HSI is an excellent tool for quality asphalt aggregates. Fine Production -A HSI promotes fines production. Crushed Faces -The HSI provides a high % crushed faces. 48

49 Secondary and Tertiary Crushing Cone Crushers 49

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51 Secondary and Tertiary Crushing Get info from Kimball 51

52 Secondary and Tertiary Crushing Vertical Shaft Impact Crusher (VSI) 52

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54 Secondary and Tertiary Crushing Type of Crusher -The VSI is an impact crusher. The material is crushed by it s impact with the table shoes or rotor rock pockets, and further broken as it impact the stationary anvils or rock shelf. Application -The application is typically as a third or fourth stage crusher for low to med abrasive materials. Particle Shape -The VSI provides high quality product when properly fed. The VSI is an excellent tool for shaping and beneficiating aggregates. Fine Production -A VSI promotes fines production. Crushed Faces -The VSI provides a high % crushed faces. 54

55 Secondary and Tertiary Crushing How it Works 55

56 Screening Equipment Selecting the right type of screen for the application. Incline Vibrating Screens Horizontal Vibrating Screens High Frequency Screens 56

57 Flow circuit for MAX Production Non-Selective Circuit Material from primary jaw and secondary cone is mixed with material from tertiary cone TPH for Max Production Rate Red lines indicate slabby material

58 Gradation versus Specification Generally speaking, the crusher produces a gradation, but the screen produces the specification.

59 Screening Theory Backbone of the Crushing Circuit: In the majority of crushing circuits, screening is usually the bottleneck not the crushing. Proper screening is so important to the circuit, it is essential to cover the topic when discussing crushers.

60 Screening Theory Never Cut Corners on Screening The vibrating screen is the cash register in any operation. This is not a unit machine in the circuit that can afford to be undersized. Determination of the critical decks must be determined with consideration given to future markets. Custom blending and tighter aggregate specifications may require detailed review of product chute design. This type of design may affect the types and heights of screen structures.

61 Screening Theory Stratification must occur before Separation can occur!!

62 Stratification and Separation Feed Material Overs (Product) Material that passes over screening surface Throughs (Product) Material that passes though screening surface

63 Screen Styles Vibrating Screens Used In The Aggregate Industry

64 Screen Styles Types of Primary Screens in the Aggregate Industry 1. Inclined/Sloped Screens Low stroke, low G-force Gravity propels material down the screen 2. Horizontal Screens Large stroke, high G-force Screen movement propels material down the screen 3. High Frequency

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66 Inclined Screen 66

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75 Screen Cloth Wire Cloth More throughput and production Readily available Less expensive than rubber or polyurethane More adaptable design options Up to 10 foot wide widths and variable length options 75

76 Screen Cloth Square Opening Wire Cloth 76

77 Screen Cloth Double Weave Handles high-impact loads and wears better than heavier singlestrand wire Excels with large feed materials Reduces screen cloth change-outs and production costs per ton Improves material throughput by up to 50% with more open area than perforated punch plate Increases the volume of material you can process 77

78 Screen Cloth Double Weave 78

79 Screen Cloth D,W and T Style Screens Accelerates stratification, increasing material throughput by up to 40% Provides up to 30% more screen capacity than traditional woven wire screen media Eliminates blinding, pegging and clogging Minimizes downtime spent cleaning/replacing screens 79

80 Screen Cloth D,W and T Style Screens 80

81 Material Handling Equipment 81

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84 Material Segregation Factors that affect pile gradation and segregation Haul trucks Feed source quarry or pit face. Stockpiling stackers Front end loading into trucks Segregation during truck transport 84

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90 Material Load Out Causes of Segregation Segregation occurs in the formation of a traditional conical stockpile. As the product is transported by conveyor, vibration and motion of the belt causes fine particles to settle on the bottom of the pile. Coarse particles at the top of the material stream have a higher velocity as the material reaches the head pulley, and are thrown a greater distance. The resulting stockpile is segregated, with coarse particles settled at the toes, and fine particles in the center portion of the pile. 90

91 Material Load Out Remedies for Stockpile Segregation When loading from a segregated stockpile, the loader operator will attempt to blend material from the fine and coarse portions. This is best accomplished by drawing the material evenly from the edge of the pile perpendicular to the belt, thereby loading material from both the front and back face. Loading exclusively from either the front or back face of the stockpile will result in loads that are overly fine or overly coarse 91

92 Material Load Out Remedies for Stockpile Segregation When loading from a segregated stockpile, the loader operator will attempt to blend material from the fine and coarse portions. This is best accomplished by drawing the material evenly from the edge of the pile perpendicular to the belt, thereby loading material from both the front and back face. Loading exclusively from either the front or back face of the stockpile will result in loads that are overly fine or overly coarse 92

93 Agg Flow Software 93

94 Thank You QUESTIONS? 94