a vertical cement mill with a high efficiency separator will be used for raw coal grinding and drying. the nominal capacity of the mill is 25t/h of coal pulverized at 10% reject on 80 microns sieve. the raw coal bin will be equipped with a load cell. bin and extraction must be dedusted. the raw coal will be adjusted by weigh feeders. a metal separator is installed before the raw coal is fed to the vertical mill to eliminate metallic parts. the dust collected by the bag filter will be the qualified coal powder, which will be transported either to a bin for kiln or to a bin for precalciner. the dedusted air from the bag filter will be to the chimney. a fresh air inlet with damper will also be included in the mill air circuit. the design dust concentration in the dedusted gas will be lower than 50mg/nm3. the cooler exhaust gases will be used to dry the raw coal in the vertical cement mill. an auxiliary air heater is requested. the pulverized coal extracted from the bins by two sets of weighing and feeding systems will be pneumatically transported to the kiln and precalciner burners. the capacities will be 7~9t/h for the kiln burner and 10~12t/h for the precalciner burner. the transporting air is supplied from roots blowers. the workshop will also include necessary explosion valves, co and temperature detection and co fire protection, etc.
two cement grinding system will be adopted and each system includes a roller press and a æ4.2´12.0m cement mill in closed circuits with o-sepa high efficiency classifier. the nominal capacity of each cement mill system will be 120t/h of ordinary portland cement at fineness of 320m2/kg. the main motor power of each mill is about 2800kw. proportioned mixture are conveyed via belt conveyor and elevator below the proportioning bins to feeding bin, which is equipped with three load cells, above the roller press. the weight signal sent by the cells serves as the feedback signal of materials flow to control the feed volume of belt weigher under the proportioning bins for mixture. materials from the roller press are sent to v-shaped powder separator. coarse particles return to the feeding bin above the roller press. fine product taken by the airflow is sent to cyclone collector and then to the ball cement mill for grinding. those cannot be caught by cyclone collector are sent to o-sepa separator of the ball cement mill by airflow. materials ground by ball cement mill are transported to n2500 o-sepa separator by high efficiency bucket elevator. the coarse particles separated return to ball cement mill for regrinding while the fine product is collected by the high efficiency bag filter behind the separator and then conveyed to cement silo via an air slide and bucket elevator.
vertical cement mill works in the last part of the cement production line, supplying right size cement powder for the industry. zenith lm series vertical mill is widely used for ore and stone crushing production line. we produce lm vertical mill with high capacity long service time, with a decade of years’ research of mills, vertical roller mill is designed and manufactured based on our advanced design idea, and in combination with the european technology and the market demand. cement ball mill is the most widely used cement mill in cement manufacturingindustry. the materials are fed into cement ball milling cavity, which will roll with materials and grinding balls, and then with continues rolling the materials will be resized into cement powder. it is widely used in building material, chemical industry, etc. there are two ways of grinding: the dry process and the wet process. it can be divided into tabular type and flowing type according to different forms of discharging material. cement roller mill is a new kind of large scale power mill which is designed specially to solve the problems of low capacity and high consumption of industry cement mills. with a decade of years’ research of mills, cement roller mill is designed and manufactured based on our advanced design idea and best materials.