Lithium battery lead powder temperature in production technology

The temperature control in the melting point of lead ( 327℃） Melting point and orthorhombic system PbO ( 885℃） In between. The transformation temperature, temperature range is polycrystalline by rhombic PbO to tetragonal PbO transformation temperature is 486 ℃. In 1908, patton Borton） A patented invention, with a hot pot of molten lead oxide, melting temperature of about 450 ℃, melting molten lead by pumping reactor, the reactor is a pan, the temperature is about 47. ℃ molten lead in the pot, stirring constantly into powder, a stream of air flow in reactor lead liquid oxidation, and blow the oxidation of lead particles from liquid table into the classifier. Here coarse grain of fine particle separation, and coarse grain back to the reactor again, to make coarse oxidation, dispersed, again to classifier. Exhaust gas is filtered is discharged into the air after cleaning system, the discharge amount of lead to ensure that is extremely low. Barton production of lithium battery lead oxide oxidation degree is 80%. Lead oxide in the high temperature reactor, mostly orthorhombic system. At lower temperature in the reactor, rhombic Pbo and tetragonal Pbo co-exist at the same time. Lead acid lithium battery industry preferred tetragonal PbO, therefore lead oxide reaction temperature should be chosen in the low range, polycrystalline transition temperature below 486 ℃. Barton powder in a small amount of rhombic PbO ( 15%) The formation, the impact is not big to lead acid lithium battery parameters. Typical barton lead oxide particles, there will be the combination of thick spherical mass crystal chips, has not been rough lead oxide particles are spherical particles. Barton tank ( The reactor) The temperature; Blowing ( Air) The speed; Blowing ( Air) Humidity; The temperature of the molten lead pot, molten lead flow reaction tank ( The reactor) The flow velocity. The above parameters analysis discussed below. ( l） The influence of the temperature of reaction tank when reaction tank temperature, the degree of oxidation of lead oxide also increased. Lithium battery lead powder suction acid value increase, production also increases. Lead oxide ( Yellow) Amount of rhombic PbO also is in the lead powder increases, and only a small amount ( Red) Tetragonal PbO. Meanwhile lead oxide the true density and apparent density were also reduced, lead powder particle size and surface area remain the same. When the temperature of the reactor is lower, the deer bounded under the temperature dropped to l, flow into the reactor of lead will be solidified into a big piece or mass. ( 2) The influence of the air flow rate in a system under high air velocity increase production efficiency, the same particle size, the true density and apparent density will increase. At the same time, however, lead powder suction suction acid value will decrease, specific surface area is also reduced. ( 3) Its true density, apparent density will reduce, suction acid value increases, the production equipment capacity and particle size, specific surface area lead oxide will remain the same. Improve the level of air moisture, can through the general regulation of spray a small amount of water into the reaction tank. ( 4) Lead the influence of the temperature of the pot of molten lead pot temperature remains near the lead melting point, in order to prevent the molten lead in reaction tank before, from cooling and solidification. To this end, the most common is between molten lead pot and reaction tank set a lose lead tube heat preservation, often heat pipe heat preservation. In order to prevent the molten lead pot temperature sudden drop, so people lead raw material cannot too much at a time, on the other hand, don't pay attention to the molten lead pot temperature is too high, Below 450 ℃) To avoid forming dross loss. ( 5) The influence of feed rate lead feed speed depends on the lead into the molten lead pot in reaction tank liquid velocity, it is a basic way to control the reaction tank temperature required. Therefore any increase lead feeding speed will lead to the corresponding reaction tank temperature, at the same time is bound to cause lead powder properties change. Obviously lead feed speed directly depends on the production capacity of the equipment. Feeding speed is done through automatic control device ( To control) , the change of the feed speed is affected by the current instantaneous changes.