For the crushing circuit below, 135 tons of dry ore feed containing 75% Class 1 and...

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For the crushing circuit below, 135 tons of dry ore feed containing 75% Class 1 and 35% Class 2 is being fed as new feed (F) to the crushing circuit. The crusher product (D) is discharged onto the screen. The screen allows all of class 3 to go through as undersize circuit product (P) and 50% of class 2. The rest goes back to the crusher as recycling (R). Given that there are only three classes with the following size ranges; (Class 1-80 +40cm), (Class 2 - 40 +25cm), and (Class 3 -25cm) (For ref purposes use the upper screen i.e to calculate Ci for Class 1, used di=55) New Feed R The Breakage Matrix (B') is given as: [0.58 0 0 0 0.38 0.59 10.04 0.35 0.62] During crushing motion, the maximum opening K2 is always 1.5 X K1, the closed setting. C = 1- - [di K] K-K where Cis the classification function, K is the Closed Crusher setting (CCS) and K2, the widest possible opening at a given CCS. di is the particle size. The overall breakage model with classification function included is as follows; d = (1-C)(IBC)-f Note in this case d is the crusher product and S is the screen model which you calculate by applying the given rules. Questions: 1. establish a crusher Closed Side Setting (CSS) size that will yield a Product S that contains anywhere between 65 and 80% Class 3. 2. Estimate the energy used by the circuit to produce the product in question 1 if the work index is 18.5. 3. If everything stays the same, calculate the product's value without the screen. 4. Calculate the CSS to obtain the same product as in Q1, but this time without a screen included. 5. Design a two-stage crushing circuit that has both open and closed circuits and briefly comment on it. For the crushing circuit below, 135 tons of dry ore feed containing 75% Class 1 and 35% Class 2 is being fed as new feed (F) to the crushing circuit. The crusher product (D) is discharged onto the screen. The screen allows all of class 3 to go through as undersize circuit product (P) and 50% of class 2. The rest goes back to the crusher as recycling (R). Given that there are only three classes with the following size ranges; (Class 1-80 +40cm), (Class 2 - 40 +25cm), and (Class 3 -25cm) (For ref purposes use the upper screen i.e to calculate Ci for Class 1, used di=55) New Feed R The Breakage Matrix (B') is given as: [0.58 0 0 0 0.38 0.59 10.04 0.35 0.62] During crushing motion, the maximum opening K2 is always 1.5 X K1, the closed setting. C = 1- - [di K] K-K where Cis the classification function, K is the Closed Crusher setting (CCS) and K2, the widest possible opening at a given CCS. di is the particle size. The overall breakage model with classification function included is as follows; d = (1-C)(IBC)-f Note in this case d is the crusher product and S is the screen model which you calculate by applying the given rules. Questions: 1. establish a crusher Closed Side Setting (CSS) size that will yield a Product S that contains anywhere between 65 and 80% Class 3. 2. Estimate the energy used by the circuit to produce the product in question 1 if the work index is 18.5. 3. If everything stays the same, calculate the product's value without the screen. 4. Calculate the CSS to obtain the same product as in Q1, but this time without a screen included. 5. Design a two-stage crushing circuit that has both open and closed circuits and briefly comment on it.