Ball mill cooling system and method

Abstract

A cooling system for a ball mill for producing lead oxide is disclosed. The system has: an internal nozzle configured to introduce water into an interior of a rotating ball mill drum; and a water conduit on the exterior of the rotating drum and configured for external water delivery to deliver water onto the exterior of the drum. A control system for controlling the cooling system may also be provided. A method is also disclosed.

Description

[0001] This application is a divisional application of the invention patent application with an application date of November 12, 2019, an international application number of PCT / US2019 / 060978, a national application number of 201980087925.5, and an invention name of “Ball Mill Cooling System and Method”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority to U.S. Provisional Patent Application Serial No. 62 / 759,969, filed on November 12, 2018, entitled “BALL MILL OXIDE COOLING SYSTEM & METHOD,” the entire contents of which are hereby incorporated by reference in their entirety. Technical Field

[0004] The present invention relates to the field of oxide production. The present invention more specifically relates to the field of lead oxide production. The present invention also relates to the field of batteries (e.g., lead-acid batteries, including batteries for vehicle starting, lighting and ignition applications; marine batteries; commercial batteries; industrial batteries; batteries for hybrid electric vehicles, micro-hybrid vehicles, etc.), and lead oxide for use in such batteries. Background Art

[0005] Lead oxide is often used to produce the paste used on the battery plates of lead-acid batteries. That is, lead oxide can be used to make a paste that is applied to the grid to form the electrodes of the lead-acid battery. After chemical conversion, the paste becomes an active material.

[0006] More specifically, the positive plate of the lead-acid battery can include a substrate having a lead dioxide active material or paste thereon. Examples of lead-containing compositions that can be used in the positive electrode paste include, but are not limited to, finely divided elemental Pb, PbO ("lead monoxide" or "yellow lead"), Pb3O4 ("red lead"), PbSO4 ("lead sulfate" The term "PbSO4" is defined to also include its associated hydrates, and basic sulfates: 1PbO.PbSO4, 3PbO.PbSO4.H2O, 4PbO.PbSO4), and mixtures thereof. Different materials can be used with respect to the lead-containing paste composition, and the present invention is not limited to any specific material or mixture (added fibers or other ingredients). These materials can be used alone or in combination as determined by many factors, including, for example, the intended use of the battery and other materials used in the battery.

[0007] The negative plate may also consist of a substrate with a sponge-like lead active material or paste thereon. The negative electrode paste may be substantially similar to the positive electrode paste, but may also be different. Example lead-containing compositions that may be used in the negative electrode paste include, but are not limited to, finely divided elemental Pb, PbO ("lead monoxide" or "yellow lead"), Pb3O4 ("red lead"), PbSO4 ("lead sulfate" term "PbSO4" is defined to also include its associated hydrates, and basic sulfates: 1PbO.PbSO4, 3PbO.PbSO4.H2O, 4PbO.PbSO4), and mixtures thereof. In addition, the negative electrode active material may also contain fibers and / or "expander" additives, which may, among other purposes, help maintain the active material structure and improve performance characteristics. Different materials may be used with respect to the lead paste composition, and the present invention is not limited to any specific material or mixture (added fibers or other ingredients). These materials may be used alone or in combination as determined by many factors, including, for example, the intended use of the battery and other materials used in the battery.

[0008] Various lead oxides can generally be made by reacting pure lead metal with oxygen in the air. A variety of processes are used to produce lead oxide, one of which is the ball mill process. As explained in further detail below, certain ball mill devices and processes have various disadvantages. Summary of the invention

[0009] An improved ball mill cooling system and method for producing lead-containing oxides is provided. Among other features, the improved system utilizes both internal and external cooling to the ball mill during the oxide production process.

[0010] More specifically, a cooling system for a ball mill for producing lead oxide is disclosed. The system has an internal water inlet configured to introduce water into the interior of a rotating ball mill drum; and a water conduit located on the exterior of the rotating drum and configured for external water delivery to deliver water to the exterior of the drum. A water source is provided, the water source being in communication with the internal water inlet and the water inlet configured for external water delivery. A control system is also provided, the control system communicating with the internal water inlet and the water conduit to function the internal water inlet and / or the water conduit, and communicating with one or more sensors configured to monitor the condition of the rotating drum or the material contained therein.

[0011] A method for producing lead oxide using a ball mill is also disclosed. The method includes: introducing a certain load of lead into the interior of a rotating drum of the ball mill; operating the rotating drum to rotate; moving air through the rotating drum by maintaining an inlet pressure differential; and cooling the rotating drum of the ball mill. Cooling includes: introducing water into the interior of the ball mill drum in response to and based on the condition of the ball mill, and introducing water onto the exterior of the ball mill drum in response to and based on the condition of the ball mill.

[0012] A ball mill for producing lead oxide is also disclosed. The ball mill includes a rotating drum operably connected to a motor for rotating the drum. The rotating drum has one or more agitators therein. A particle feed chute is positioned for delivering material for producing lead oxide to the rotating drum. An internal water port is configured to introduce water into the interior of the ball mill drum for a period of time. A water conduit is disposed on the exterior of the rotating drum and is configured for external water delivery so as to deliver water to the exterior of the drum. A water source is in communication with the internal water port and the water port configured for external water delivery.

[0013] These and other features and advantages of devices, systems and methods according to the present invention are described in or are apparent from the following detailed description of various examples of embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Various examples of embodiments of the systems, devices and methods according to the present invention will be described in detail with reference to the following drawings, in which:

[0015] Figure 1 is a schematic diagram of a ball mill lead oxide manufacturing facility.

[0016] Figure 2 is a cross-sectional view of an example ball mill with integrated cooling for use with the methods and systems described herein.

[0017] Figure 3 is a block diagram illustrating a control system for cooling a ball mill according to one or more examples of the embodiments described herein.

[0018] Figure 4 Sample test results from one or more experiments are presented, showing a box plot of the BET test results.

[0019] Figure 5 Sample test results from one or more experiments are presented, showing box plots of acid absorption values.

[0020] Figure 6 Sample test results from one or more experiments are presented, showing a box plot of the BET test results.

[0021] Figure 7Sample test results from one or more experiments are presented, showing a box plot of the BET test results.

[0022] Figure 8 Sample test results from one or more experiments are presented, showing box plots of water absorption values.

[0023] Fig. 9 Sample test results from one or more experiments are presented, showing a statistical graph of the percentage of free lead.

[0024] Fig.10 Sample test results from one or more experiments are presented, showing a box plot of the percentage of free lead.

[0025] Fig.11 Sample test results from one or more experiments are presented, showing a summary of the data distribution and percentage of free lead resulting from cooling a ball mill using only external cooling and cooling a ball mill using both internal and external cooling as described herein.

[0026] Fig.12 Sample test results from one or more experiments are presented, showing a box plot of 5 micron TOL demonstrating particle size.

[0027] Fig.13 Sample test results from one or more experiments are presented, showing a box plot of 7.5 micron TOL demonstrating particle size.

[0028] Fig.14 Sample test results from one or more experiments are presented, showing a box plot of 10.5 micron TOL demonstrating particle size.

[0029] It should be understood that the drawings are not necessarily drawn to scale. In some cases, details that are not necessary for understanding the present invention or that render other details difficult to understand may have been omitted. Of course, it should be understood that the present invention is not necessarily limited to the specific embodiments shown herein. DETAILED DESCRIPTION

[0030] According to one or more examples of embodiments, lead oxide (which is used to create a paste used on battery plates) is produced by a ball mill process.

[0031] In the ball mill process, high-purity lead of various size configurations is usually allowed to tumble in a rotating mill or rotating drum. The drum acts much like a rock tumbler or a clothes dryer. The drum has an agitator that tumbles the raw lead material inside. The tumbling causes collisions with the lead particles, thereby forming smaller particles that react and oxidize into a combination of lead and lead oxide (lead-containing oxide or oxide) when heated. This action generates heat, which in turn oxidizes the lead. More specifically, a lead block or lead ingot is filled into the ball mill together with air. The friction heat generated by the tumbling lead ingot triggers the oxidation reaction. The oxygen in the air reacts with the lead to produce lead oxide by means of the heat of the tumbling lead. During grinding, the fine particles of lead oxide and unoxidized lead formed on the surface of the lead ingot are broken, thereby forming fine dust that can be removed from the mill by circulating airflow. Centrifugal mills and cyclone separators are usually used to collect large particles, while finer particles are usually collected in bag filters. In one or more examples of embodiments, the output produced by the ball mill process is lead oxide and, in some examples, unreacted free lead. For example, the output may consist of 70 to 75 weight percent (wt%) lead oxide and the remainder, which is (e.g., 25% to 30%) free lead. Although some free lead is pasted into the battery plates during battery manufacturing, the remaining free lead that is not solidified in the pasted plates is wasted.

[0032] In reference Figure 1 In another example described, lead ingots are melted in a furnace 100. The molten lead in the furnace 100 is pumped to a cylinder casting machine 102. Lead columns are cast in the cylinder casting machine 102 at a rate higher than the oxidation process rate. These lead columns are transported and stored in a silo 104. The silo 104 delivers the required amount of lead columns to a ball mill 106 as and when needed. The amount of lead columns discharged from the silo 104 can be adjusted by, for example, a control system or PLC system 108.

[0033] As shown, the lead columns tumbling inside the ball mill drum 110 generate heat due to the friction between the lead columns. This heat initiates the oxidation process. The oxidation process is also an exothermic reaction. This exothermic heat increases the temperature of the material, which in turn accelerates the oxidation process. A sensor or thermocouple 112 is used to monitor the reaction temperature and the reaction temperature is controlled by periodic water cooling.

[0034] The air flow through the ball mill drum 110 provides oxygen for the oxidation process and also transports the battery lead oxide to a collection system. The collection system may include a combination of a cyclone separator and a dust collector or just a dust collector 114. The lead oxide is collected and transported to a storage silo 116. In some examples, the silo 116 storing the battery oxide is purged with nitrogen to keep the temperature of the oxide under control.

[0035] In some examples of embodiments, the ball mill process can be performed on or in a 24T (24 ton) system. In other examples of embodiments, the ball mill process can be performed on or in a 30T (30 ton) system. Note that the "ton" or "T" designation relates to the amount of oxide that can be produced within a twenty-four (24) hour period. Thus, a 30T ball mill can produce a greater amount of lead oxide than a 24T ball mill in the same period of time.

[0036] As shown, the reaction temperature is monitored using a sensor or thermocouple 112 and controlled by periodic water cooling. In the ball mill 106 disclosed herein, a novel cooling system is employed. Figure 2 1 shows an example ball mill 106 using combined cooling (both internal and external cooling). In one or more examples of embodiments, the ball mill 106 is a 30T ball mill. The ball mill 106 for producing lead oxide has a rotating drum 110, which is operably connected to a motor for rotating the drum, and has one or more agitators 118 in the rotating drum 110. A particle feed trough 120 is positioned for delivering materials (e.g., lead) for producing lead oxide to the drum or rotating drum 110. An internal water inlet 122 is provided and is configured to introduce water into the interior 124 of the ball mill drum 110. In one or more examples of embodiments, the internal water inlet 122 can be positioned inside the drum 110, adjacent to the inlet of the particle feed trough 120. A water conduit 126 is also provided, which is located on the exterior 128 of the rotating drum 110 and is configured for external water delivery so as to deliver water to the exterior 128 of the drum. In some examples, the water conduit 126 extends the entire length of the drum 110. A water source 130 is also provided that communicates with the internal water port 122 and the conduit 126 configured for external water delivery.

[0037] As shown, the oxidation reaction is exothermic and therefore provides heat that can speed up the process, but if the heat is not adequately controlled, it may overheat and fail to meet appropriate production requirements. Therefore, in one or more examples of the embodiment, the temperature of the ball mill process is controlled. Therefore, a control system or PLC (programmable logic controller) 108 can also be provided, which communicates with the internal water inlet 122, the water pipeline 126, and / or the water source 130 to activate water delivery through the internal water inlet and / or the water pipeline, and communicates with one or more sensors 112 or thermocouples, which are configured to monitor the condition of the rotating drum 110 or the material contained therein (see Figure 3). The sensor 112 or the thermocouple is configured to transmit a signal to the control system in response to the condition to communicate the condition. The control system can then decide to deliver water or stop delivering water through the combined cooling system water delivery mechanism (i.e., the internal water port 122 and / or the water pipe 126).

[0038] Traditionally, 24T ball mills are internally cooled. In other words, in a 24T ball mill, water is introduced into the rotating drum in order to counteract the heat generated by the oxidation reaction and control the temperature. This can be achieved by using a water nozzle to spray water internally for a period of time at certain intervals based on, for example, the temperature of the ball mill. For example, the temperature of a conventional 24T oxide ball mill is regulated by spraying water internally on one side of the rotating drum directly behind the particle entry slot.

[0039] Unlike the 24T ball mill, due to the increase in drum size, traditionally, the 30T ball mill is externally cooled (on the outside of the drum), because it has been found that internal cooling is not efficient in larger capacity mills. Therefore, there is no internal water spraying at all in the traditional 30T ball mill. More specifically, in order to cool the 30T ball mill and / or maintain a certain temperature or temperature range, a pipeline or other pipeline is provided outside along the entire length of the drum. The pipeline is based on the temperature of the mill in some examples, for example, water is sprayed to one side of the drum at various intervals for a period of time to cool the mill. Excess water usually goes to a drainage structure.

[0040] Notably, the effects of different cooling methods (i.e., cooling a typical 24T ball mill versus cooling a typical 30T ball mill) have been found to result in completely different reactions. More specifically, each conventional cooling method results in a different shaped oxide material with different reactivity. The lead oxide surface area also changes. Further, there are distinct rheological differences between the oxides produced by the two conventional units. In addition, the oxides produced by the conventional 30T ball mill do not react as well as the oxides produced by the 24T ball mill. Therefore, depending on the mill size / capacity, different paste formulations are often required or used for battery paste production using conventional ball mills, which can be inefficient and problematic for battery manufacturing.

[0041] Therefore, a novel method for producing lead oxide using a ball mill, and in particular a 30T ball mill 106, is provided herein. The method includes introducing a certain amount of lead into the interior of a rotating drum 110 of a ball mill 106, the range of lead being approximately 40% to 60%. The rotating drum 110 is operated to rotate at a desired torque. Air is moved through the rotating drum 110 by maintaining an inlet pressure difference. During the process, the rotating drum 110 is cooled by: water is introduced into the interior 124 of the ball mill drum 110 in response to and based on the condition of the ball mill, and water is introduced to the exterior 128 of the ball mill drum 110 in response to and based on the condition of the ball mill. Water can be delivered from the same position as external cooling or from a different position. Both the flow rate and frequency of water delivery can be controlled. Various conditions can be used to trigger a cooling mechanism, i.e., water delivery. In one example, the condition of the ball mill is the temperature of the drum or the material therein. In another example, the condition of the ball mill is time or a time period. In yet another example, the condition of the ball mill is water volume. In some examples of embodiments, the cooling process can be automated. In other examples of embodiments, the cooling process can be manually operated.

[0042] In order to implement the aforementioned method, a cooling system for a ball mill for producing lead oxide, and in particular 30T balls, can be provided. The system has: an internal water inlet 122, which is configured to introduce water into the interior 124 of the ball mill drum; a water conduit 126, which is located on the outside 128 of the drum 110 or the rotating drum and is configured for external water delivery so as to deliver water on the outside of the drum; and a water source 130, which is connected to the internal water inlet and the water inlet configured for external water delivery. Therefore, external water delivery is provided along the outside of the drum, and the internal water inlet 122 for water delivery can be placed inside the drum, for example, adjacent to the particle feed trough 120 of the drum. Water can be delivered to the internal water inlet 122 from the same position as the external cooling water delivery system. Reference Figure 3 , a control system 108 (which may be a PLC) is provided, which communicates with the internal water inlet 122, the water pipe 126, and / or the water source 130 to enable the cooling system (i.e., the internal water inlet and the water pipe and / or the water source) to function, i.e., trigger the delivery of cooling water. Therefore, the control system 108 is also in communication with one or more sensors 112 (such as but not limited to thermocouples), which are configured to monitor the condition of the drum 110 or the rotating drum or the material contained therein and transmit signals to the control system.

[0043] Therefore, an improved ball mill system and method is provided herein. In one or more examples of embodiments, the ball mill is cooled internally and externally. That is, a combined cooling system is used, wherein water is introduced into the drum for a period of time by spraying water internally at certain intervals using water ports based on conditions such as the temperature of the drum or the ball mill, and water is also sprayed downward to the outside or exterior of the drum for a period of time based on conditions such as the temperature of the ball mill, and excess water goes to a drainage structure.

[0044] The ball mill can be operated according to one or more of the following example parameters, either alone or in any combination. For example, the ball mill can be operated at a temperature ranging from approximately 120 degrees Celsius to 150 degrees Celsius. In another example, the ball mill can have a certain load, for example, the amount of lead inside the mill, the range of lead is from approximately 30% to 70% (1% load = approximately 200kg of lead). In yet another example, the ball mill can be operated or rotated with a torque of approximately 2500 to 8500kg. In another example, the range of the inlet pressure difference (e.g., the air moving through the mill) can be from approximately 10mmH2O to 70mmH2O. In another example of an embodiment, the quality of water for internal cooling and / or external cooling can also be adjusted. The mill setting can also determine the flow rate and frequency of conveying cooling water. Although various specific examples are described, it will be understood by those skilled in the art that modifications can be made for the intended purpose without departing from the overall scope of the present invention. For example, while water may be introduced based on temperature and / or time, it is also contemplated that water may be introduced based on volume or other factors or manufacturing characteristics designed to achieve a desired paste formulation.

[0045] Although the systems and methods described herein are specifically described for use with a 30T ball mill, those skilled in the art will appreciate that the same systems and methods can be equally applicable and functional to ball mills of other sizes (greater and less than 30T). Likewise, although water is described herein, those skilled in the art will appreciate that other liquids may be suitable for the purposes of the present invention.

[0046] Example

[0047] The following examples are illustrative of one or more examples of implementing embodiments of the present invention, and are not intended to limit the scope of the present invention. As will be seen from the following examples of experimental results, various parameters have been improved or changed due to the ball mill with combined cooling described herein.

[0048] Example 1

[0049] Figures 4 to 8Sample test results from one or more experiments are presented showing improvements in BET, acid absorption, and water absorption using the ball mill cooling method described herein.

[0050] “BET” refers to the Brunauer-Emmett-Teller (BET) theory, which is commonly used to evaluate gas absorption data and generate specific surface area results (area per sample mass (m 2 / g)). In this test, physically bound impurities are usually removed from the surface of the sample to be tested by degassing or outgassing before analysis. The specific surface area of ​​the material can then be determined by physical adsorption of a gas (for example, nitrogen, krypton or argon, depending on the expected surface area and the nature of the sample) on the sample surface at cryogenic temperatures (usually the temperature of liquid nitrogen or liquid argon). Once the amount of adsorbed gas is measured (by volumetric flow techniques or continuous flow techniques), calculations assuming a monolayer of known gases are applied. The results are shown in box plots. According to the literature, the BET results for the measured oxides typically range from 0.5 m 2 / g to 2m 2 / g.

[0051] Acid absorption ("AA") is a conventional analytical method commonly used in the manufacture of lead oxide, which is used to make pastes and / or electrodes for lead-acid batteries. Typically, the acid absorption of a material is determined by a standard but empirical procedure in which a weighed amount of the sample is treated with sulfuric acid and the amount of acid absorbed is determined. The result is determined as milligrams of sulfuric acid per gram of lead oxide (mg H2SO4 / g PbO). According to the literature, typical test results range from 220 mg H2SO4 / g PbO to 300 mg H2SO4 / g PbO.

[0052] In this example, ball mills were tested in two different manufacturing facilities. In each facility, multiple samples were tested on a 24T ball mill and multiple samples were tested on a 30T ball mill. The 24T ball mill was operated according to a conventional method using only internal cooling. In some tests, the 30T ball mill was operated under a conventional method using only external cooling as described above, and in other tests, the ball mill was operated by implementing the improved ball mill cooling system and method described herein using both internal cooling and external cooling. In Tables 1 and Figures 4 to 5 The results shown in demonstrate BET and acid absorption of lead oxide using traditional methods.

[0053] Table 1: BET and acid absorption

[0054]

[0055]

[0056] Figure 6 to Figure 7 Tables 2 and 3 show the results of the BET values ​​after adding internal cooling to the 30T ball mill. "30T Int." used in this example and other examples herein refers to a 30T ball mill using the novel process described herein including having external cooling itself and adding internal cooling.

[0057] Table 2: BET values ​​after adding internal cooling

[0058] Ball mill sample Day <![CDATA[BET(m 2 / g)]]> 10 1 1 1.92 10 2 1 2.10 10 3 1 2.05 10 1 2 1.98 10 2 2 2.03 10 3 2 2.00 10 1 3 1.77 10 2 3 1.45 10 3 3 2.43 10 1 4 2.35

[0059] Table 3: BET average values

[0060] facility type <![CDATA[BET average value (m 2 / g)]]> 1 24T 1.76 2 24T 1.84 1 30T 3.24 2 30T 1.93 1 30T Int. 2.00

[0061] As can be seen from the results, it is shown that in one facility, using the same ball mill, the BET surface area is reduced by 62 percent (%) after adding internal cooling to a conventional 30T mill. That is, it is shown that the BET of the 30T ball mill (ball mills 10 and 11 in the example shown) is 3.0 m when only external cooling is used. 2 / g to 3.5m 2 / g or an average value of 3.24m 2 / g. In contrast, it is shown that when the same 30T ball mill is operated using both external cooling and internal cooling as described herein, the BET of the ball mill ranges from about 1.5 m 2 / g to 2.5m 2 / g or an average value of 2.00m 2 / g.

[0062] Figure 8 Table 4 shows test results demonstrating water absorption of lead oxide. Tests were conducted using a conventional 24T ball mill, a conventional 30T ball mill, and a 30T ball mill utilizing both external and internal cooling. The values ​​are expressed as an average of milliliters (ml) of water (H2O) / 100 grams (g) of oxide.

[0063] Table 4: Average water absorption values

[0064] type Average value of ml H2O / 100g oxide 24T 11.39ml 30T 12.59ml 30T Int. 11.65ml

[0065] From the results, it can be seen that the 30T ball mill lead oxide paste formulation produced without internal cooling (i.e., produced under the conventional method using only external cooling) requires approximately 25 pounds (lb) of water in addition to the 30T ball mill using both internal cooling and external cooling. The 30T ball mill using external cooling and internal cooling operates similarly to the 24T ball mill, requiring approximately 5 lb of water in addition to the 24T ball mill. In addition, these results show that the variation in the mixture formulation consistency and water usage is much smaller due to the addition of internal cooling in the 30T ball mill.

[0066] Example 2

[0067] The novel ball mill and cooling method described herein were also tested for free lead produced during the formation of lead oxide. Lead oxide consists of metallic lead (Pb) and oxidized lead (PbO). "Free lead" is the exposed metal portion of the lead oxide. Generally, the more free lead there is, the less growth there is in the final lead oxide product. Although a certain amount of free lead is desired, the more free lead there is, the more conversion cost and time there is, which reduces the yield of the process.

[0068] The results of various tests for free lead are Figures 9 to 11 and are shown in Tables 5 and 6. Fig. 9 In the graph of FIG. 1 , the percentage of free lead is plotted against density. It can be seen that the percentage of free lead measured has a peak density (and higher density) of an average free lead percentage of approximately 28.00 with external cooling alone, compared to a lower peak density of a lower average free lead percentage of approximately 27.31 with the addition of internal cooling (including both internal and external cooling). Fig.10 A similar reduction in the percentage of free lead is reflected in the box plot shown, where the percentage of free lead is lower after internal cooling is added to the ball mill.

[0069] Over a period of several months, two samples were tested for their free lead percentage on a 30T ball mill using only external cooling and on a 30T ball mill using both internal and external cooling. The results are shown in Tables 5 and 6. "Before IC" and "After IC" refer to the establishment of internal cooling.

[0070] Table 5: Test results of 2 samples for free lead percentage

[0071]

[0072] Table 6: Specification range

[0073]

[0074]

[0075] Fig.11 A summary and comparison of the free lead percentage tests for two samples are provided, the percentage being obtained by cooling the ball mill using only external cooling and cooling the ball mill using both internal cooling and external cooling as described herein. The average free lead percentage and data distribution when internal cooling is not added are significantly different from the average free lead percentage and data distribution after internal cooling is added. The entire interval (95% CI) is below zero.

[0076] As can be seen from the foregoing examples, the amount of free lead shows an improvement, i.e., a reduction in free lead resulting from the combined cooling process. When considering manufacturing or production volume, even a small reduction (e.g., less than 1%) in free lead without a reduction in output is important.

[0077] Example 3

[0078] In another example, the apparent density of a 24T ball mill and a 30T ball mill was tested to assess the particle size in the respective mills. Multiple ball mills in multiple facilities were tested. Each ball mill sample was measured using (multiple) HELOS particle distribution sensors. The specifications were as follows: 5 microns (um)_85±3% TOL; 7.5um_90±3% TOL; 10.5um_94±3% TOL. Figure 12 to Figure 14 and Table 7 show sample test results showing apparent density, ie, an example indication of particle size in a 24T ball mill and a 30T ball mill.

[0079] Table 7: Particle size test results

[0080]

[0081]

[0082] As previously shown in previous examples, in some examples, the ball mills 10, 11 include external cooling and internal cooling according to the novel process described herein. It can be seen that the TOL value of the 30T ball mill is generally improved compared to the 24T ball mill.

[0083] Although various specific examples have been described so far, it will be appreciated by those skilled in the art that additional tests and examples can be provided and modifications can be made to the intended purpose without departing from the overall scope of the invention. For example, among others, other factors that can be measured and / or improved are impurities and surface area.

[0084] It can be seen from the foregoing that as a result of the combined cooling process of the 30T ball mill, the surface area of ​​the lead oxide is reduced, and in some examples of the embodiment, its surface area may be similar to the product of the 24T process. In addition, the combined cooling process results in a reduction in free lead. For example, in some examples of the embodiment, the combined cooling process in the 30T ball mill results in a 2% to 3% decrease in free lead compared to the typical output of the 24T process. Note that, in contrast, in order to produce a decrease in free lead, the production volume of the conventional 24T process needs to be slowed down. This shows the reactions occurring in the 30T ball mill utilizing combined cooling and the increase in ball mill output. Therefore, the introduction of internal water into the 30T ball mill provides additional cooling for the 30T ball mill equipment, which also increases the loading capacity and therefore increases the output, thereby resulting in an increase in machine output.

[0085] In addition to cooling the ball mill, in the improved systems and methods described herein utilizing combined (internal and external) cooling, further oxidation reactions and other chemical reactions may occur due to the introduction of water and water vapor directly into the ball mill. The rheology of the paste mixture may also be altered due to the increased reactivity of the generated oxide with the internal water. That is, the combined cooling system (i.e., adding internal water to an externally cooled 30T ball mill) changes the properties of the generated oxide, which makes the coating operation during battery plate manufacturing more consistent and increases the degree of oxidation of the lead oxide product. Therefore, due to the combined cooling process, a similar paste formulation used for the 24T process can be used in a 30T ball mill.

[0086] Thus, the combined cooling process for the 30T ball mill makes the mixture formulation consistent with the 24T ball mill process, showing the physical changes of the final product compared to the original 30T ball mill process, and the different reactions inside the ball mill due to internal cooling, for example, catalyzing the reaction in addition to cooling, that is, catalyzing the reaction with water vapor. At the same time, the output of the ball mill can be increased. In view of the various advantages described above, the methods and systems described herein allow manufacturers to operate at higher capacities / loads and at increased speeds, thereby increasing the output of the ball mill. The increase in output and the change in the composition of the lead oxide also help to improve the performance of the final battery product and the manufacturing rate of the final battery product.

[0087] As used herein, the terms "substantially," "approximately," "substantially," and similar terms are intended to have a broad meaning consistent with common and acceptable usage by those of ordinary skill in the art to which the subject matter of the present disclosure belongs. Those skilled in the art who read the present disclosure should understand that these terms are intended to provide a description of certain features described and claimed without limiting the scope of these features to the precise numerical ranges provided. Therefore, these terms should be understood to indicate that insubstantial or inconsequential modifications or changes to the subject matter described and claimed are considered to be within the scope of the present invention as described in the appended claims.

[0088] It should be noted that references to relative positions (eg, "top" and "bottom") in this specification are only used to identify the orientation of various components as they appear in the drawings. It should be appreciated that the orientation of specific components may vary greatly depending on their application.

[0089] For purposes of this disclosure, the term "coupled" means that two members are connected to each other directly or indirectly. Such connection may be fixed in nature or removable in nature. Such connection may be achieved by forming the two members, or the two members and any additional intermediate members, integrally as a single piece with each other, or by attaching the two members, or the two members and any additional intermediate members, to each other. Such connection may be permanent in nature, or may be removable or releasable in nature.

[0090] It is also important to note that the construction and arrangement of the systems, methods and devices shown in various examples of the embodiments are illustrative only. Although only a few embodiments are described in detail in the present disclosure, it will be readily apparent to those skilled in the art that many modifications are possible (e.g., changes in the size, dimensions, structure, shape and proportion of each component, the value of a parameter, mounting arrangement, material use, color, orientation, etc.) without substantially departing from the novel teachings and advantages of the subject matter. For example, a component shown as being integrally formed may be constructed from multiple parts, or a part shown as multiple parts may be integrally formed, a connection operation may be reversed or otherwise changed, the length or width of the structure and / or components or connectors or other components of the system may be changed, and the nature or number of adjustment positions set between components may be changed (e.g., by a change in the number of engagement grooves or the size of the engagement grooves or the type of engagement). The order or sequence of any process or method steps may be changed or reordered according to alternative embodiments. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangements of various examples of the embodiments without departing from the spirit or scope of the present invention.

[0091] Although the present invention has been described in conjunction with the examples of the embodiments summarized above, various alternatives, modifications, variations, improvements and / or substantially equivalent schemes, whether known or currently foreseeable, may become apparent to those of ordinary skill in the art. Therefore, the examples of the embodiments of the present invention as previously stated are intended to be illustrative rather than restrictive. Various changes may be made without departing from the spirit or scope of the present invention. Therefore, the present invention is intended to include all known or earlier developed alternatives, modifications, variations, improvements and / or substantially equivalent schemes.

[0092] The technical effects and technical problems in this specification are exemplary rather than limiting. It should be noted that the embodiments described in this specification may have other technical effects and may solve other technical problems.

Claims

1. A cooling system for a ball mill for producing lead oxide, the cooling system comprising: an internal water inlet configured to introduce water into the interior of a drum of the ball mill to cool the drum and / or the material therein; a water conduit located on the exterior of the drum and configured for external water delivery to deliver water to the exterior of the drum; a water source in communication with the internal water inlet and the water conduit configured for external water delivery; as well as A control system, the control system communicates with the internal water inlet, the water conduit, and / or the water source to enable the water source, the water inlet, and / or the water conduit to function and deliver water to cool the drum and / or the material therein, and the control system also communicates with one or more sensors, the one or more sensors being configured to monitor the condition of the drum or the material contained therein and transmit a signal to the control system in response to the condition.

2. A cooling system for a ball mill for producing lead oxide, the cooling system comprising: an internal water inlet configured to introduce water into the interior of a drum of the ball mill to cool the drum and / or the material therein; a water conduit located on the exterior of the drum and configured for external water delivery to deliver water to the exterior of the drum; a water source in communication with the internal water inlet and the water conduit configured for external water delivery; as well as a control system that communicates with the internal water inlets, the water conduits, and / or the water source to cause the water source, the water inlets, and / or the water conduits to function and deliver water to cool the drum and / or the material therein, and that communicates with one or more sensors that are configured to monitor a condition of the drum or the material contained therein and transmit a signal to the control system in response to the condition, wherein the control system is configured to operate the water source, the water inlet, and / or the water pipeline and deliver water based on the signal transmitted by the one or more sensors in response to the condition to increase the consistency between the lead oxide produced by the ball mill and the lead oxide produced by another ball mill, and the ball mill has a higher capacity than the other ball mill.

3. The cooling system according to claim 1 or 2, wherein: The condition is the temperature of the drum.

4. The cooling system according to claim 1 or 2, wherein: The condition is a time or a time period.

5. The cooling system according to claim 1 or 2, wherein: The condition is the amount of water.

6. The cooling system according to any one of claims 1 to 5, wherein: The flow rate and frequency of water delivery are controlled.

7. The cooling system according to claim 1 or 2, wherein: The ball mill is a 30-ton ball mill.

8. The cooling system of claim 2, wherein: The other ball mill produces lead oxide by introducing only water into the interior of a drum of the other ball mill.

9. The cooling system of claim 2, wherein: The ball mill is a 30-ton ball mill, and the other ball mill is a 24-ton ball mill.

10. A lead oxide product formed by a ball mill using a cooling system as claimed in any one of claims 1 to 9.

11. A method for producing lead-containing oxide using a ball mill, the method comprising: introducing a certain loading amount of lead into the interior of the rotating drum of the ball mill; operating the rotating drum to rotate; moving air through the rotating drum by maintaining an inlet pressure differential; and Cooling the rotating drum of the ball mill by: In response to and based on the condition of the ball mill, introducing water into the interior of the rotating drum; and Responsive to and based on the conditions of the ball mill, water is directed onto the exterior of the rotating drum.

12. A method for producing lead-containing oxide using a ball mill, the method comprising: introducing a certain loading amount of lead into the interior of the rotating drum of the ball mill; operating the rotating drum to rotate; moving air through the rotating drum by maintaining an inlet pressure differential; and Cooling the rotating drum of the ball mill by: In response to and based on the condition of the ball mill, introducing water into the interior of the rotating drum; and directing water onto an exterior of the rotating drum in response to and based on a condition of the ball mill; wherein, in response to and based on the condition of the ball mill, water is introduced to the interior and exterior of the ball mill drum to increase the consistency between lead oxide produced by the ball mill and lead oxide produced by another ball mill, and the ball mill has a higher capacity than the other ball mill.

13. The method according to claim 11 or 12, wherein: The ball mill is a 30-ton ball mill.

14. The method according to any one of claims 11 to 13, wherein: The condition of the ball mill is the temperature of the rotating drum.

15. The method according to any one of claims 11 to 13, wherein: The condition of the ball mill is time or time period.

16. The method according to any one of claims 11 to 13, wherein: The condition of the ball mill is the amount of water.

17. The method according to any one of claims 11 to 16, wherein: The flow rate and frequency of water delivery are controlled.

18. The method according to any one of claims 11 to 17, wherein: The cooling process is automatic.

19. The method of claim 12, wherein: The other ball mill produces lead oxide by introducing only water into the interior of a drum of the other ball mill.

20. The method of claim 12, wherein: The ball mill is a 30-ton ball mill, and the other ball mill is a 24-ton ball mill.

21. A lead oxide product formed by the method of any one of claims 11 to 20.

22. A ball mill for producing lead oxide, the ball mill comprising: a rotating drum operably connected to a motor for rotating the rotating drum, the rotating drum having one or more agitators therein; a particle feed chute arranged to deliver material for producing lead oxide to the rotating drum; as well as A cooling system as claimed in any one of claims 1 to 9.

23. The ball mill according to claim 22, wherein: The internal water inlet is arranged inside the rotating drum adjacent to an inlet of the particle feed chute.

24. The ball mill according to any one of claims 22 to 23, wherein: The water conduit extends over the entire length of the rotating drum.

25. The ball mill according to any one of claims 22 to 24, wherein: A control system communicates with the internal water inlet and the water conduit and / or the water source to function the internal water inlet and / or the water conduit, and the control system communicates with one or more sensors configured to monitor the condition of the rotating drum or the material contained therein and transmit a signal to the control system in response to the condition.

26. The ball mill according to any one of claims 22 to 25, wherein: The ball mill is a 30-ton ball mill.

27. A lead oxide product comprising any one or any combination of the technical features of claim 10.

28. A lead oxide product comprising any one or any combination of the technical features of claim 21.

29. A ball mill for producing lead oxide, comprising any one or any combination of the technical features of claims 22-26.

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