1. We need the final product in this size gradations
a) 0-3 mm - we treat this as stone dust which is normally considered as waste. Very rarely this is used in a small quantity for asphalt work. So this is waste, which needs to be screened out.
(b) 3-8 mm :- This is called zero size product here and is very useful in our all the activities like asphalting, concreting and making the hollow block bricks.
(c) 8-14 mm :- This is called no.-1 size here and the most useful product. This is the main product. This is widely required and under great demand.it's percentage in design mixes are about 40-50% . So our aim is to get this size product as much as possible.
(d) 14-22 mm :- This is called no.- 2 size product. This is required but very less in percentage in design mixes.( even less than 20%). So our aim remains to reduce the percentage of this product. Although this is not waste but this is not required much here. Our aim should remain to get minimum percentage of this product.
(e) Normally we dont need +22-40mm sizes but there should be provision of getting this product from Screen-1(VS1) and Screen-2(VS2) also as this may be required some times in road projects.
Now based on this requirement I reccommend following changes in the circuit.
1.The VS-2 should be 4-deck in place of 3 deck. Alternatively if we still use 3 deck in that case the bottom most screen should have two part. First part for 0-3 mm material and second part 3-8 mm material. Hence there should be two chutes below the screen. Thus total 4 belt conveyors for output materials and one for recycling of +22 mm material totaling 5 belt conveyors at this point.
2.Since our main material requirement lies between 3mm to 14 mm so I pesonally feel that despite 2 nos. of cone crushers in tertiary stage we should go for one no. Impact crusher. This may provide good shape of material also as well as more quantity of smaller sizes products. This could be VSI ot HSI. In Libya the HSI ( Horizontal shaft impact crushers are widely used.). So far I have not seen even a single VSI here in this place. So please confirm do you manufacture Horizontal Shaft Impact Hammer crusher? If no, in that case please provide a suitable model of VSI. Also please let me know the product percentage as per our required gradation and the most optimum RPM of the VSI.
Please note that our final aim is to get minimum possible percentage of 0-3 mm and 14-22 mm sizes and as much as possible 3-8mm and 8-14mm sizes.
3. I reccommend to remove stone dust/soil powder ( 0-5 mm) from VS-1 which could be impurity and useless items. This should be removed out here and +5to -20mm size material can be directly sent to VS-2. Kindly suggest the outcome of this chages. ■
What's suitable equipement recomanded
1. We need the final product in this size gradations
a) 0-3 mm - we treat this as stone dust which is normally considered as waste. Very rarely this is used in a small quantity for asphalt work. So this is waste, which needs to be screened out.
(b) 3-8 mm :- This is called zero size product here and is very useful in our all the activities like asphalting, concreting and making the hollow block bricks.
(c) 8-14 mm :- This is called no.-1 size here and the most useful product. This is the main product. This is widely required and under great demand.it's percentage in design mixes are about 40-50% . So our aim is to get this size product as much as possible.
(d) 14-22 mm :- This is called no.- 2 size product. This is required but very less in percentage in design mixes.( even less than 20%). So our aim remains to reduce the percentage of this product. Although this is not waste but this is not required much here. Our aim should remain to get minimum percentage of this product.
(e) Normally we dont need +22-40mm sizes but there should be provision of getting this product from Screen-1(VS1) and Screen-2(VS2) also as this may be required some times in road projects.
Now based on this requirement I reccommend following changes in the circuit.
1.The VS-2 should be 4-deck in place of 3 deck. Alternatively if we still use 3 deck in that case the bottom most screen should have two part. First part for 0-3 mm material and second part 3-8 mm material. Hence there should be two chutes below the screen. Thus total 4 belt conveyors for output materials and one for recycling of +22 mm material totaling 5 belt conveyors at this point.
2.Since our main material requirement lies between 3mm to 14 mm so I pesonally feel that despite 2 nos. of cone crushers in tertiary stage we should go for one no. Impact crusher. This may provide good shape of material also as well as more quantity of smaller sizes products. This could be VSI ot HSI. In Libya the HSI ( Horizontal shaft impact crushers are widely used.). So far I have not seen even a single VSI here in this place. So please confirm do you manufacture Horizontal Shaft Impact Hammer crusher? If no, in that case please provide a suitable model of VSI. Also please let me know the product percentage as per our required gradation and the most optimum RPM of the VSI.
Please note that our final aim is to get minimum possible percentage of 0-3 mm and 14-22 mm sizes and as much as possible 3-8mm and 8-14mm sizes.
3. I reccommend to remove stone dust/soil powder ( 0-5 mm) from VS-1 which could be impurity and useless items. This should be removed out here and +5to -20mm size material can be directly sent to VS-2. Kindly suggest the outcome of this chages. ■