Each composite was stage-crushed to P 100 of 6 mesh (3.35 mm), blended, and submitted for a Bond ball mill grindability test (closing screen …
operating work index) is also presented a product of for each simulation. For Greenfield design of an AG/SAG-ball mill circuit with JKSimMet, the additional power requirement in the ball mill(s) is determined with the Bond ball mill work index and the phantom cyclone technique. COMMINUTION Trusted Bench Scale and Pilot Scale
Bond Work Index an overview ScienceDirect Topics. Ball mill design requires a Bond work index, BWi, for ball mills at the correct passing size; SAG mill design requires an appropriate SAG test, for example, SPI (Chapter 5) Flotation design needs a valid measure of kinetics for each sample, including the maximum attainable recovery and rate constants for each mineral (Chapter 12) Take care to ...
Here, W IB is the work index, kw∙h∙t − 1; and P i is the sieve size of the test (µm). The ball mill produces a new material smaller than P i per lap, g∙R − 1. P and F respectively represent 80% generation particle size and the ore feeding particle size through the mesh size (µm).
The basic parameters used in ball mill design (power calculations), rod mill or any tumbling mill sizing are; material to be ground, characteristics, Bond …
The Bond Ball Mill Work Index can be used in the design calculations and simulations of a new grinding circuit. A Bond Ball Mill Work Index may also be used in the simulation and optimisation of existing mill(s) and the associated grinding circuit(s). Sample …
This Grindability Test or Bond Ball Mill Work Index Procedure is used to determine the Bond Work Index of minus six mesh or finer feed ore samples. These equation application methods are used to process <1/2″ ore samples in a Ball Mill using a standard ball charge.. Below describes in general terms the Bond Work Index Procedure used by a Professional Metallurgical Testing Laboratory.
Comminution tests (ball mill grindability) returned average Bond Work Index (BWI) values that categorize MET-1 as medium and MET-2 as moderately soft. More testwork will be undertaken to improve the 24- to 48-hour gold recoveries and optimize the leach residence time. Improvements are expected with these tests.
Bond Crusher Work Index; Bond Abrasion Work Index; Bond Ball/Rod Mill Indices; J-K Drop Weight Test* SMC Test®* Starkey SAG Design Test* Starkey SAG Variability Test (SVT)* Unconfined Compressive Strength (UCS) HPGR; VXP *Licensed to conduct this test work at our facility, data is interpreted and results reported by the parent company.
Bond Test WI's (kWh/t): Rod Mill: Ball Mill: 9.5 kWh/t.8 9 kWh/t . Bond Standard Circuit Work Index: Assume the rod mill Work Index of 9.5 applies from the actual rod mill feed sizeof 19,300 mµ (although some of this work might ideally be done by crushers to achieve a rod mill F80 of 16,000 m) to a rod µ
An improved method using less mass compared to the Bond Ball Mill Work Index test. The JK Bond Ball Mill (JKBBM) test, is a locked cycle grindability test conducted using a standard laboratory Bond Ball Mill with the same steel ball charge and material feed size ( passing 3.35 mm) as the Bond Ball Mill Work Index test.
Bond Test WI's (kWh/t): Rod Mill: Ball Mill: 9.5 kWh/t.8 9 kWh/t . Bond Standard Circuit Work Index: Assume the rod mill Work Index of 9.5 applies from the actual rod mill feed sizeof 19,300 mµ (although some of this work might ideally be done by crushers to achieve a rod mill F80 of 16,000 m) to a rod µ
Raw Bond Model. This is a SAG or AG mill plus ball mill model that estimates the specific energy consumption (E SAG) using the 1979 Barratt equation and the classical Bond work index equation including Rowland efficiency factors.The model allows a manual calibration factor on both equations (CF SAG and CF ball, respectively).This formula usually gives higher total circuit specific energy ...
Bond Work Index (BWI) & Hardgrove Grindability Index (HGI) tests for biomass & coal. • BWI can predict the potential for mill choking of biomass in a tube and ball mill. • HGI is a poor method of predicting grindability of biomass in vertical spindle mills. • Pellets should be composed of pre-densified particles close to the target size. •
Since for the ball mill design we are using 80% passing, the required value of C2 for the ball mill will be equal to1.20. C3 is the correction factor for mill diameter and is given as; 𝐶𝐶3 = 2.44 𝐷𝐷 0.2 (3) However, it is important to note that C3 =0.914 vessel used in producing the ball mill was got from a
Bond Work Index - an overview | ScienceDirect Topics
in terms of SAG power index, SPI (for SAG grinding) and Bond Ball mill work index, BWi (for ball mill grinding). A further measure, the Minnovex crusher index, Ci was also measured for use in the CEET program to determine SAG mill feed size (Kosick and Bennett, 2001). The SPI values varied from 13.5 to 107 minutes with an average of 53 minutes.
Design engineers generally use Bond equation to estimate specific energy requirements using a parameter called, Bond Work Index, which is determined experimentally in a laboratory ball mill [1–3]. Morrell [ 4 – 6 ] has proposed different …
The parameter Wi, known as the work index of the ore, is obtained from batch bench tests first devised by Bond (1961). The power calculated on using equation 1, (Bond, 1961; Rowland and Kjos, 1978), relates to: 1) Rod milling – a rod mill with a diameter of 2.44 meters, inside new liners, grinding wet in open circuit.
Bond Ball Mill Test; 3.4.7 ... Factors Affecting the Work Index; 3.5.1; Effect of the Test Screen Size on Work Index; 3.6; Approximation Methods for Work Index3.6.1; Magdalinovic Method; 3.6.2; Methods Using a Non-Standard Mill and Charge; 3.6.3 ... * Outlines the theory and practice in the design of flow sheets and operation of an integrated ...
design to specify a feed and product size plus a hardness index to produce a specific energy value (kWh/t). ... submitted to the Bond ball mill work index test. The number of SAG mill revolutions required to grind the ... EF4 and EF5 factors for ball milling (Rowland, 1982).
Bond Ball Mill Work Index, BWi, kWh/t 13.4 Bond Rod Mill Work Index, RWi, kWh/t 18.1 Table 1. Example of AG/SAG Ball Mill Circuit Wio Calculations [1] [2] ABstrAct Optimum use of power in grinding, both in terms of grinding efficiency and use of installed capital, can have a large effect on profitability.
The ability to simulate the Bond work index test also allows examination of truncated ball mill feed size distributions on the work index. For grinding circuits where the feed to a ball mill is sent directly to the classifier and the cyclone underflow feeds the ball mill (see Figure 3.10), a question arises as to whether this practice will alter the ball mill work index (BW i) of the material ...
The amount of feed was set at 1175 g, which was proportional to industrial scale.The ball mill speed was constantly set at 76.8% Cs.Experiments were conducted at different ball sizes (between 20 and 40 mm), grinding time (10–30 min), solids content (65–80%) and work index of copper sulphide ore (12–15.4).RSM and Box–Behnken design were used for the experimental design and modeling of ...
The Bond work index is a measure of ore resistance to crushing and grinding and is determined using the Bond grindability test. Its value constitutes ore characteristic and is used for industrial comminution plants designing. Determining the Bond work index value is quite complicated, timeconsuming and requires trained operating personnel and therefore is subjected to errors.
Bond/Rowland rod mill ball mill model. This is a rod mill feeding a ball mill model that estimates the specific energy consumption (E RM and E BM) using the Rowland interpretation of the classical Bond work index equation including Rowland efficiency factors.. There are two varieties of this model, one based on feed generated by closed-circuit crushing and other based on feed generated by open ...
pressure grinding rolls (HPGR) products based on a Bond mill test procedure. Multiple trade-off studies have reported the performance of HPGR versus SAG milling with energy savings of between 11 and 32 per cent. One factor that is often inconsistently defined in these studies is the change in the Bond Ball Work Index (BBWi).
rod mill work index has not been de ned as yet. The ball fi mill work index is con rmed at 16 kWh/t. The operating fi work index, though, is in the range of 21 kWh/t to 25 kWh/t showing high ineffi ciency. This raises the point that, in some cases, the Bond EF4 …
bond ball mill work index test standard pdf. 1 Introduction A Bond Ball Mill Work Index test is a standard test for determining the ball mill work index of a sample of ore It was developed by Fred Bond in 1952 and modified in 1961 (JKMRC CO 2006)This index is widely used in the mineral industry for comparing the resistance of different materials to ball milling for estimating the energy,
* Bond F. C., "Crushing Tests by Pressure and Impact", Trans AIME, Vol 169, 1947, pp 58-66. Bond Rod Mill Grindability Test. The test determines the Bond Rod Mill Work Index which is used with Bond's Third Theory of Comminution to calculate net power requirements when sizing ball mills*. Various correction factors may have to be applied.
In conjunction with the Bond ball mill work index they can be used to accurately predict the overall specific energy requirements of circuits containing: • AG and SAG mills. • Ball mills • Rod mills ... These factors are best discussed with your local metallurgical laboratory when you are at the planning stage. However, in the majority of ...
Since for the ball mill design we are using 80% passing, the required value of C2 for the ball mill will be equal to1.20. C3 is the correction factor for mill diameter and is given as; 𝐶𝐶3 = 2.44 𝐷𝐷 0.2 (3) However, it is important to note that C3 =0.914 vessel used in producing the ball mill was got from a
The basic parameters used in ball mill design (power calculations), rod mill or any tumbling mill sizing are; material to be ground, characteristics, Bond Work Index, bulk density, specific density, desired mill tonnage capacity DTPH, operating % solids or pulp density, feed size as F80 and maximum 'chunk size', product size as P80 and maximum and finally the type of circuit open/closed ...