OXB C140 OXIDE BALL MILL
BALL MILL FOR LEAD OXIDE
MODEL: OXB C140 w w w . z e s a r . c o m . t r
OXB C140 OXIDE BALL MILL
The ball mill lead oxide production process is based on well-­‐known Shimadzu method. Small metallic lead (Pb) cylinders are charged with air into a ball mill. Frictional head generated by the tumbling lead cylinders initiates and oxidation reaction. Oxygen in the air, assisted by the heat of the tumbling lead, reacts with the lead to produce lead oxide. During milling, the lead oxide that forms on the surface of the cylinders and fine particles of un-­‐oxidized lead are broken off, forming a fine dust that is removed from the mill by a circulating air stream. Centrifugal mills and cyclones are used to collect large particles, while the finer particles are collected in a bag house. The oxidation level of the lead may be adjusted by changing temperature and airflow. The unit comprises of following main parts. Automatic Ingot Feeder
Automatic lead feeding transfers lead ingots one by one to melting pot. It is initiated by “low level” sensors at melting pot. The operation is repeated until the sensor for maximum level is triggered. Includes: i. Ingot Lifting Hoist with Clamp • Electrical hoist • Flag type • 1.5m range • Lifting capacity 300kg, 5 – 6 lead ingots at a time. ii. Ingot Feeder • Electrically welded steel frame • Chain feeder • 1.5 kW gear motor. • Up to 40 ingots capacity iii. Ingot Elevator • Steel Frame • Pusher chain • 0.5 kW gear motor Lead (Pb) Melting Pot
The lead melting pot is provided for melting of ingots. The upper part is equipped with suction hood and exhaust outlet. Working temperature range between 450°C and 550°C. Includes: i. Structure & Insulation • Rugged rectangle metallic frame • Multiple layer insulation ii. Pot • Welded steel plate • Bottom drain • 2.600 kg melting capacity iii. Heating System • Gas or Electrical heating (45kW) • For gas heating, “zero-­‐low-­‐medium-­‐
high” fire to save energy • For electrical heating, standby status (15kW) to save energy • Control Unit Lead (Pb) Pump
A high efficiency centrifugal pump does lead supply. Feeding Line
Lead supply is done through a heating tube heated and temperature sensor equipped lead feeding line. Cylinder Caster
The cylinder caster is designed to produce small lead cylinders for the production of lead oxide (PbO). Cavities in spheroid crown are filled with molten lead and ejected vertically after cooling. A bucket elevator feeds the cylinders into cylinder silo. Includes: i. Base • Steel framework ii. Spheroid Crown • Cast iron • 1 ton/hr capacity with 90 cavities • 90 steel stems for ejection • Cylinder dimensions Ø18 X 18(h) mm. w w w . z e s a r . c o m . t r
OXB C140 OXIDE BALL MILL
• Height can be controlled by flow regulating valve. • 0.75 kW motor reducer iii. Cooling System • Internal cooling with water Bucket Conveyor
A conveyor, with metal buckets fixed on a chain collects the incoming cylinders from the cylinder caster and carries them to the storage silo. • 8000 kg/hr capacity • 2.20 kW installed power Cylinder Silo with Load Cells
Lead cylinders are stored in a silo. • 30 tons capacity • Equipped with 4 X 15 tons load cells and module control box • Conveyor belt to main system Main Drum
When the weighing system moves down the setting point, required amount of lead cylinder is loaded from the cylinder silo into the rotating main drum. Negative pressure created by the fan installed at the base of bag house generates airflow, causing lighter lead oxide powders to move from mill to the filter. All operating parameters are displayed and modified by means of a touch screen connected with the PLC. Life expectancy 30 years. Includes: i. Main Drum • Electrically welded and mechanically worked Steel • SS 304 base support • Equipped with load cells • 14 tons/day capacity • 75 kW total installed power • Internal Temperature between 120° C and 130° C. ii. Transmission Group • Reducer gear group iii. Lubricating System • Automatic lubricating pump • PLC set lubrication time iv. Cooling System • Internal water cooling • Temperature measurement at 3 inner points • PLC control v. Outer Housing • SS 304 PbO Output: • Oxidation: 68 – 72% • Acid Absorption: 230 – 260g of H2SO4/cm3 PbO • Apparent Density: 1.10 – 1.40gr/cm3 • Grain < 44 micron: 94 – 98% • Acid Reaction Time: 20 – 60 sec • Water Absorption: 10.5 – 12.5 cm3 H2O/100g PbO Pulse Bag House
A centrifugal fan placed at the lower section of the bag house sucks air from rotating main drum and brings lead oxide powder into the bag house. Also, heat due to exothermic reaction of PbO is reduced. When the air-­‐PbO mixture enters the bag house, %50 of the powder in air accumulates at the bottom on screw conveyor. Remaining PbO is filtered when air passes through the bags. Finally, clean air leaves the filter and passes through a secondary filter to make sure no impurity is present before releases in the environment. Includes outlet for oxide sample. Includes: i. Filter Bags • 120 pieces woven nomex filter bags made in Germany • 70 – 90 °C discharging temperature • Discharging speed 16m/sec maximum • Maximum emission on the air 5 μgr/m3 ii. Filter Body • Reinforced steel plate w w w . z e s a r . c o m . t r
OXB C140 OXIDE BALL MILL
iii. Vacuum Fan • 14 kW centrifugal fan • ± 7.200 m3/hr maximum ejected air Secondary Filter (Optional)
A secondary filter after the bag house prevents any leakage of the bag filter. Bags made in Germany. Negative Blower
A negative blower is used to suction the powder from main drum to bag house. Also, transfers the air t to go into the main drum at the same time. Screw Conveyor & PbO Elevator
Includes: i. Screw Conveyor • From bag house to silo and from silo to paste mixer • Continuous spiral made of mild steel is welded on a center pipe • Supported by ball bearings • Gear motor to provide motion • End bearing with seal to prevent outflow of PbO ii. Screw Conveyor • From bag house to silo and from silo to paste mixer • Cups to collect PbO and lift up to discharge point • Sealed with iron sheet carter Oxide Silo
Lead oxide is stored in the silos. • 40 tons capacity • Equipped with 4 X 15 tons load cells and module control box • Temperature monitoring with sensor • Special provision for bagging of oxide into sacks • With vibrators Control Panel The control panel is equipped with SIEMENS PLC and 6AV6647-­‐0AG11-­‐3AX0 model 15” wide touch screen, which controls all the operations related to: • Cylinder transport • Cylinder silo • Ball Mill • Oxide extraction system from the main drum • Oxide transport to the silo Specifications
• PLC System SIEMENS S7-­‐1200 • Main Motor: SIEMENS • Color: RAL5015 • Height Clearance Required: 9.5m System Capacity
• Nominal: 14tons/day • Achievable: up to 18 tons/day Utilities
Ø Main System Voltage: 220V/380V – 50 HZ Ø Air Pressure: 6 – 7bar Ø Fuel: Naturel Gas (0 – 300 mbar) w w w . z e s a r . c o m . t r