single SAG mill, a two stage grinding circuit is recommended. 4 SELECTION OF AN APPROPRIATE SINGLE STAGE CONFIGURATION The first step in designing a single stage circuit is the selection of the optimum circuit configuration. Single Stage AG and SAG circuits can be sub-divided into a number of
AG/SAG mill and crusher circuit simulations through the use of JKSimMet. Independent of this it can be used in power-based calculations, which in conjunction with the Bond ball work index test, enable the prediction of the specific energy of comminution circuits
This flowsheet is typical of many mills that have been built throughout the world. Figure 3 shows a typical semi-autogenous (SAG) circuit with feed coming directly from a primary crusher, and the semi-autogenous mill product going to the separation process.
While the two SAG mills at Mt Keith are identical in design, their operation is not due tosegregation of the coarse and fine material in the stockpile that provides feed to the grinding circuit. Therefore, the two circuits operate under different conditions and this has always presented a challenge for maximising throughput and optimising grind ...
• 28 MW GMD for a 40' SAG mill • 28 MW GMD for 42' SAG mill Whether it is size or an installation at the highest altitude (4600 m.a.s.l.), ABB's GMDs are well positioned to contribute to the building of larger and ever more powerful mills. — Leading the gearless mill drive evolution The ABB gearless mill drive (GMD) is the most powerful ...
single SAG mill, a two stage grinding circuit is recommended. 4 SELECTION OF AN APPROPRIATE SINGLE STAGE CONFIGURATION The first step in designing a single stage circuit is the selection of the optimum circuit configuration. Single Stage AG and SAG circuits can be sub-divided into a number of
The discharge grates of the SAG mill were identified as a key component in the SABC circuit, and their design is a crucial factor in the mill's performance [17][18][19] [20] [21]. The initial ...
AG and SAG mills are now the primary unit operation for the majority of large grinding circuits, and form the basis for a variety of circuit configurations. SAG circuits are common in the industry based on: High single-line capacities …
Grinding Circuit Modelling Documentation. This documentation describes the operating and underlying mathematics of the SAGMILLING grinding circuit modelling program. It is intended to be used by the model users who want to operate and understand the functioning of grinding models.
grinding circuit (crushing, single-stage ball mill). Thus, the Etotal of a SAG and ball mill circuit is: Etotal=1.10×E ( 5 ) Partitioning the Total Energy Between SAG and Ball Mills The Bond-based method applied by Barratt involves deducting a SAG mill specific energy consumption, ESAG, from the overall circuit specific energy consumption ...
In his approach the total specific energy of the entire AG/SAG circuit is firstly predicted using the SAG mill feed F80 and the ball mill cyclone overflow P80.
SAG mill circuit example for gold processing [image: (135-6-3)] AG/SAG Mill AG/SAG mills are normally used to grind run-off-mine ore or primary crusher product. Wet grinding in an AG/SAG mill is accomplished in a slurry of 50 to 80 percent solids. 2D and 3D simulations of particles in a SAG Mill red=fastest, blue=slowest moving particles
AG/SAG SE values to enable the additional power required for AG/SAG milling to be determined. AG/SAG inef ciency varies according to the transfer size fi (T80), whereby the ner sizes have less ineffi ciency than the fi coarser sizes. This means a closed circuit single stage AG/ SAG mill can operate at a reasonable ef ciency if the fi nal fi
The mills can be operated in open circuit, feeding downstream secondary grinding, or operated in closed circuit as single stage mills generating a finer product size. Single stage SAG Mills are very beneficial in reducing CAPEX for plants with a staged throughput approach.
SAG mill drives (as GMDs) by some operators and principal motor designers/manufacturers until the reasons for known problems in design or manufacturing were better understood and resolved. Accordingly, the latest 40 ft dia. SAG mill is rated at 29 MW and 78% C.S., with a 42 ft dia. mill built but not yet operational. The more recent option
Gearless mill drive (GMD) technology has further expanded the use of large AG milling allowing Outotec to produce the world's largest SAG mill of 42' in diameter drawing power at 28 MW. Today, Outotec is the world leading supplier of gearless AG mills operating globally.
circuit or the overall performance of an autogenous-semiautogenous (AG-SAG)/ball mill circuit, but they are of limited value in evaluating AG-SAG and ball mill sections separately. This problem arises due to the difficulty of describing particle size distributions with different shapes by one number, the eighty percent passing size. This
Where the SAG mill/ball mill circuit is the bottleneck in the processing plant the pebble circuit can be a significant factor in limiting overall plant capacity. The pebble circuit recirculating load can be very significant (depending on the ore characteristics and SAG mill operating dynamics). Typically it represents around 25 % of the feed to ...
circuit is shown in Figure1. It is commonly referred to as a SABC circuit, for Semi-Autogenous Ball mill Crusher (SABC). This circuit shows a semi-autogenous grinding (SAG)/ball mill circuit where both grinding mills are in closed circuit, with the SAG mill closed with a crusher to control the amount of 'critical size' material in the circuit.
The mills can be operated in open circuit, feeding downstream secondary grinding, or operated in closed circuit as single stage mills generating a finer product size. Single stage SAG Mills are very beneficial in reducing CAPEX for …
Circuit surveys reported a SAG specific energy of 8.6 kWh/t and ball mill specific energy at 8.0 kWh/t (Dunne et al, 1999 Hart et al, 2001). The T 80 was not given so …
They will be fed to the SAG Mill circuit using conveyor by wheel loader. The SAG Mill, is a rotating cylinder containing steel balls to crush the chunks so that they have the ideal size for the process ahead. NHM currently operates two SAG Mill circuits with a total capacity of around 100 tons per hour.
to be used to predict the SAG mill circuit and ball mill circuit specific energies it is important to ascertain: 1. whether the transfer distributions obey the parallel conditions 2. what the appropriate T80 value should be for a given ore type, circuit configuration, mill geometry and operating condition 10 100 0.01 0.1 1 10 100 1000 size (mm)
Cadia in New South Wales has followed the pre-crushing circuit with a large HPGR to further reduce the SAG mill feed size as part of the Cadia East …
Next step is to add mills to the circuit: Create a new SAG mill by clicking the "+ primary mill" button. Further instructions. Continue adding mills (and pebble crushers) to the new circuit. The mills assigned to this new circuit are listed and can be edited (if necessary) by clicking the looking glass icons. Choosing the right model
in a SAG and Ball mill circuit where there is no scope for storage capacity between milling stages and throughput is normally limited by a bottleneck at one stage or the other. In this case any ore with a high BWi value will have reduced . throughput due to the ball mill despite the capability of the SAG mill to handle
Combined with a careful survey of an existing mill or detailed design of a new mill, the pulp discharge requirements can be designed with sorne confidence to avoid slurry pooling. This is of particular relevance to RoM and other SAG/AG mills operating in closed circuit.
The results showed that the HPGR-ball mill circuit achieved a 21% reduction in energy consumption over the existing SAG-ball mill circuit at the same P80 grind size of 160 mircons (μm). At a grind of 80% passing 75 μm, the HPGR-stirred mill circuit showed a 34% reduction in energy compared to the base case.
The mills can be operated in open circuit, feeding downstream secondary grinding, or operated in closed circuit as single stage mills generating a finer product size. Single stage SAG Mills are very beneficial in reducing CAPEX for plants with a staged throughput approach.
considered, such as a primary SAG and secondary ball mill circuit where the individual stages would be ESAG and Eball, and the combined total circuit CEE would be Etotal. In all cases, the specific energy consumption is defined as the motor power consumed relative to …