Teknologi Pengolahan Material Sungging Pintowantoro Department of Materials and Metallurgical Engineering,Faculty of Industrial Technology (FTI), Sepuluh Nopember Institute of Technology Surabaya (ITS), Kampus ITS, Keputih Sukolilo, Surabaya 60111, Telp/Fax : 031-5997026 Department of Materials and Metallurgical Engineering, FTI-ITS (1)

Department of Materials and Metallurgical Engineering, FTI-ITS (2)

PETA PERSEBARAN SDA INDONESIA Department of Materials and Metallurgical Engineering, FTI-ITS (3)

PETA PERSEBARAN SDA INDONESIA Department of Materials and Metallurgical Engineering, FTI-ITS (4)

Mineral Processing Overview Mineral Processing Terminology, Economics Comminution and Classification Physical processing methods Chemical processing methods Waste products treatment and disposal Process plant flow sheets: uranium and potash

Importance of Mineral Processing “No substance has been as important as metal in the story of man's control of his environment. Advances in agriculture, warfare, transport, even cookery are impossible without metal. So is the entire Industrial Revolution, from steam to electricity.” Read more: http://www.historyworld.net/wrldhis/PlainTextHistories.asp?historyid=ab16#ixzz13XSEyvNz

Importance of Mineral Processing Bronze Age- Bronze is in use in Sumer, at Ur, in around 2800 BC Iron Age - from the 11th century BC onwards, steel replaces bronze weapons. It becomes essential, from now on, to have a good steel blade rather than a soft and indifferent one.

Lecture 8 Mineral Processing Overview: Geology-Mining-Processing Relationship Mineral Processing Terms Definitions Mineral Economics review Project Stages

Lecture 9 Comminution & classification circuits Comminution Methods Principles Crushing Grinding Classification Methods Hydrocyclone Screening Assignment

Lecture # 10 Physical Processing Methods Gravity Magnetic Electrostatic Radiometric Froth Flotation Solid/liquid separation Assignment

Lecture 11 Chemical Processing Basic Circuits Leaching Solvent Extraction Precipitation Drying Downstream – Purified Product Electrowinning Smelting Assignment

Lecture #12 Waste Stream Management: Tailings Disposal Surface Underground Effluent Treatment Chemical Precipitation Membrane Technology Assignment

Lecture # 13 Saskatchewan Mill Process Flowsheets Uranium Potash Assignment

Geology – Mining – Processing All 3 aspects must be favorable to make a deposit economically viable Geology: Find it. Is it big enough to be economic? Mining: Dig it. Is it economically recoverable from the ground? Processing: Extract it. Is it economically separable from the host rock?

Prevalence of mineral processing In Saskatchewan as of 2009 there were: 3 uranium mills 8 potash mine/mills 1 gold mine/mill coal mines (thermal) Salt mine An identified diamond deposit (Fort a la Corne) An identified rare earth element deposit (Hoidas Lake)

Prevalence of mineral processing Mining is all around us! In Alberta there are: Oil sands process plants (uses mining and mineral processing techniques) Coal plants Industrial minerals (limestone) Nickel/cobalt metallurgical complex In Manitoba there are: Many copper/zinc mines and mills, feeding the Flin Flon metallurgical complex Nickel mines nearby Thompson smelter In the Northwest Territories there are: 3 operating diamond mines Gold mines

Introduction to Mineral Processing Scope of mineral processing Definitions Economics Project Stages

Mining Terminology - Review Miners send their products to their customer – the mill. Ore : Rock that contains a mineral or minerals in sufficient quantities as to make commercial extraction (mining – milling) profitable. Grade : A measure of concentration of a mineral/metal contained in rock (or ore). Gold and other precious metals – g/t or oz/t, base metals - %, uranium – kg/tonne, rare earth elements – ppm… Cut off Grade : The minimum concentration or grade of mineral that is required for rock to be considered ore. Waste : Not Ore. Ore Body: A mineralized deposit (resource) whose characteristics have been examined and found to be commercially viable. The extents of the ore body are determined by the cut-off grade. Host Rock: The rock containing an ore deposit. Typically composed of 2 or more minerals. Gangue: Minerals in the ore body that are not of economic interest

Mineral Processing Is the recovery of valuable minerals from ore Takes place in a mill, aka concentrator - because it concentrates valuable minerals by removing unwanted material. The two main products are the concentrate streams (valuable minerals) and the tailings streams (rejects).

Disciplines related to mineral processing

Fields of Metallurgical Engineering Description Example of topics Mineral Processing Beneficiation or Mineral Dressing Theory and practice of liberation of minerals from ores and their separation by physical methods at ambient conditions Crushing and grinding, magnetic and electrical methods, flotation, etc. Extractive metallurgy Chemical methods sometimes at high temperature and pressure for treating ores to recover their metal values in a pure form Leaching, precipitation, electrolysis, oxidation, reduction, etc. Metal Processing Physical metallurgy Study of physical properties of metals and alloys, preparation of alloys Crystal structure, effect of impurities, metallography, heat treatment, etc. Engineering metallurgy Processing of metals in the molten state Casting, welding, etc. Mechanical metallurgy Processing of metals in the solid state Forging, rolling, extrusion, piercing Powder metallurgy Processing of metal powders into finished products Preparation of metals in powder form, hot pressing, etc.

Engineering Terminology in Mineral Processing Circuit: The path that the ore that is being processed takes as it proceeds from one processing point to another. Flow Sheet - Drawing that indicates the path that the mineral takes within a process. Several circuits are often contained within a flow sheet Recovery Rate – The percentage of valuable metal/mineral, by mass, in the concentrate from the feed

Mineral Processing The goals of mineral processing are to: separate economic mineral particles from waste or gangue subject minerals to processes in order to concentrate them or to extract metals from them

Many forms of mineral processing Depends on feed material and desired product

Mineral Processing Terminology Concentration: Another word for grade Heads: A term that is used to denote the mineral found in the FEED to a circuit. Head Grade: aka feed concentration Concentrate: a purified mineral. May require further downstream processing to convert for end uses. Examples: Copper and nickel sulfides Tailings - Material rejected from a mill after the recoverable valuable minerals have been extracted. Industrial mineral: is used for end purpose without chemical alteration. Examples: gravel, coal Mineralogy: Description of mineral contents

What is mineral processing? a)A solid naturally-occurring compound having a definite chemical composition. b) Inorganic substance that are extracted from the earth for use by man. c) A naturally occurring inorganic element or compound having an orderly internal structure and characteristic chemical composition, crystal form, and physical properties.

Mineral classification Nonmetallic processing has some commonalities with metal processing, but lots of differences

Examples of minerals

Examples of minerals

Mineralogy determines recoverability

Impact of mineralogy We mine rocks but we concentrate minerals. Gangue minerals also important Understanding mineralogy allows design of processes Important for feasibility studies This is an overhead photo of the surface operations of Kidd Mine and shows the key ventilation infrastructure for the mine. Greater detail is given in the following slides. Kidd Mine employs the use of a predominantly exhaust-only type of ventilation system whereby the primary flows through the mine are enabled through the operation of a surface exhaust fan system. The two exhaust shafts are as follows: NVS (North Vent Shaft): The primary exhaust route for the mine air. SVR (South Vent Raise): The secondary route of mine exhaust air. The fresh air is drawn into the mine through four main routes: #2 Shaft: Primary intake. Note that the air is heated during the winter to prevent freeze-up of the shaft conveyances. #1 Shaft: Main fresh air supply for Mine D. This air is refrigerated in the summer using the Refrigeration Plant and BAC (Bulk Air Cooler) Portal: Fresh air for upper part of the mine. Air is heated during winter to prevent icing of the ramp. Open Pit: Air is drawn through the bottom of the pit for the Cold Stope.

What is mineral processing? Extract values, reject waste Conversion of mined ore into usable product More expensive/challenging with lower grade ores Numerous processing methods

Mineral Processing Methods = beneficiation + extractive metallurgy Beneficiation aka Mineral Dressing Overlap of physical and chemical methods, depending on product Where extractive metallurgy leaves off, metal processing begins

Mineral Processing Terminology Beneficiation: enrichment of ores and separation of unwanted gangue minerals subsequent metals extraction more efficient. Can be divided into two distinct steps: Liberation: the rock is broken down by mechanical means, mineral components become independent of each other, detached Separation: valuable minerals are separated by means of physical and physico-chemical methods making use of differences in specific gravity, magnetic properties, etc. Extractive metallurgy: Chemical reactions of the processes equipment where reactions take place Flowsheets – combinations of processes

Typical Beneficiation Steps

Beneficiation Terminology Comminution: Reduction of particle size Starts at mine with blasting Two basic types of equipment used: Crushing – breakage by compression Grinding – breakage by abrasion and impact

Comminution Equipment Shaft

Comminution Equipment Shaft

Beneficiation Terminology Classification : Separation based mainly on particle size Behavior affected by size, shape, and density of the particles Two common types of classifiers: Screens – dry method, coarser particles Hydrocyclones – wet method, finer particles

Classification Equipment

Beneficiation Terminology Separation Techniques take advantage of the differences in characteristics between minerals: Flotation: Attachment of minerals to air bubbles - hydrophibicity Magnetic Separation: Apply magnetic field Gravity Separation: differences in specific gravity of materials Electrostatic Separation: Apply electrostatic polarity Particle size distribution has large influence on results

Separation Equipment Flotation cell

Separation Equipment Magnetic separator

Separation Equipment Gravity separation - jig

Separation Equipment Electrostatic separator

Beneficiation Terminology Dewatering: To remove water from a substance. Also refers to the circuit where this takes place. Dewatering Techniques: Thickener: Allow gravity settling Filter: Apply air pressure to draw water out Centrifuge: Apply centrifugal force Dryer: Apply heat to evaporate Slurry Density: The amount of solids in a slurry, expressed as a percentage by weight.

Dewatering Equipment Thickener

Dewatering Equipment Disc filter

Dewatering Equipment Rotary kiln dryer

Beneficiation Terminology Waste Disposal - "Mining is waste management ..." The majority of tonnage mined must be disposed of as tailings Water used must be treated and released Tailings Dam: Built from ground waste rock discharged after processing from the mill Acid Mine Drainage: produced by exposing sulfide minerals to air and water, resulting in oxidation that generates acid. Waste Rock: Unprocessed non-mineralized / low grade mined material Water Balance: Accounting of water inputs and outputs from a mine/mill site. Water Treatment: The removal of harmful contaminants from water

Waste Disposal Tailings Dam

Waste Disposal Waste Rock Pile

Waste Disposal Acid Mine Drainage

Waste Disposal Water Balance

Mineral Processing Methods = beneficiation + extractive metallurgy Beneficiation aka Mineral Dressing Overlap of physical and chemical methods, depending on product Where extractive metallurgy leaves off, metal processing begins

Extractive Metallurgy Terminology Hydrometallurgy Leaching - the process of extracting a soluble constituent from a solid by means of a (water based) solvent Water changes solubility, by making it acidic or basic, oxidizing or reducing Solvent Extraction – transfer between immiscible fluids Ion Exchange – solid resins that adsorb/desorb dissolved chemical species Precipitation – convert dissolved into solid Crystallization via evaporation Ionic precipitation - addition of a reagent to a solution creates a metal compound whose solubility is so low that precipitation takes place immediately

Hydrometallurgy Equipment Tank leach circuit

Hydrometallurgy Equipment Solvent extraction mixer-settlers

Hydrometallurgy Equipment Ion Exchange

Hydrometallurgy Equipment Vacuum crystallizer

Extractive Metallurgy Terminology Pyrometallurgy – use of heat to induce a chemical transformation Roasting – convert to oxide form. Example: 2 CuS2 + 5 O2 → 2 CuO + 4 SO2 Smelting - uses reducing substances that will combine with those oxidized elements to free the metal. Example: 2 Fe2O3 + 3 C → 4 Fe + 3 CO2

Pyrometallurgy Equipment Smelter

Extractive Metallurgy Terminology Electrometallurgy – use of electrical energy to induce a chemical transformation Electrowinning – to precipitate a metal from solution using electric potential Electrorefining – to purify a metal by dissolving it, then re-precipitating it

Electrometallurgy Equipment Alternating anodes and cathodes in a tankhouse for electrowinning

Flowsheet examples Aluminum: from bauxite Copper: from chalcopyrite Iron: from hematite Gold – Placer, sulphide and oxide Oil Sands – Fort McMurray

Aluminum

Copper

Iron

Gold

Oil Sands

Mineral Processing Recovery Recovery : Potential for loss every step of the way, in each circuit! Tonnage vs. Recovery: A processing circuit pushed beyond its capacity will induce recovery loss Feed Grade vs. Recovery : A higher feed grade tends to have higher processing recovery Concentrate Grade vs. Recovery: A higher concentrate grade tends to result in lower processing recovery (= rejection of lower quality minerals to tailings) Concentrate Grade vs. Price: A higher quality concentrate will fetch a higher price (have lower impurity penalties) Revenue = Production (tonnes) x grade x recovery x price

Milling Operating Costs Typical relative cost of beneficiating an ore Operation % Crushing 5 - 20 Grinding 25 - 75 Flotation 25 -45 Dewatering and drying 10 -20 Other operations 5 - 10