Disclosed herein are systems and methods for processing waste egg shells into (i) a first product including calcified egg shell particles having diameters of 3μ or less, and (ii) a second product including calcified egg shell particles having diameters in a range from about 3μ to about 7μ. The first product may be used as a CaCO.sub.3 substitute for paint compositions and plastics compositions. The second product may be used as a CaCO.sub.3 blasting media substitute for use with abrasive blasting equipment.

The present invention discloses a device for pulverization and explosion suppression of low carbon gas hydrate (LCGH). A feeding chamber connects with a pulverizing chamber, and the chambers communicate through a feed port. A pulverizing air pipe and the feeding chamber communicate through a feeding air pipe; two ends of a venturi connect with an entrainment chamber and a disperser respectively; and a gas-solid separation membrane (GSSM) is disposed on a discharging port and used for preventing LCGH powder from entering the entrainment chamber from the pulverizing chamber. When an explosion is triggered, the GSSM is opened to make the LCGH powder enter the entrainment chamber. The device can store and pulverize the LCGH and spray LCGH powder to achieve combustion and explosion suppression.

The present invention discloses a device for pulverization and explosion suppression of low carbon gas hydrate (LCGH). A feeding chamber connects with a pulverizing chamber, and the chambers communicate through a feed port. A pulverizing air pipe and the feeding chamber communicate through a feeding air pipe; two ends of a venturi connect with an entrainment chamber and a disperser respectively; and a gas-solid separation membrane (GSSM) is disposed on a discharging port and used for preventing LCGH powder from entering the entrainment chamber from the pulverizing chamber. When an explosion is triggered, the GSSM is opened to make the LCGH powder enter the entrainment chamber. The device can store and pulverize the LCGH and spray LCGH powder to achieve combustion and explosion suppression.

A control method of a treatment plant for elements to be recycled or disposed of, having a crushing roll to reduce the size of the elements to be recycled or disposed of, and a screen operatively arranged upstream of the crushing roll to enable passage therethrough only of elements having a size larger than a predetermined size, includes the steps of measuring the current absorbed by the crushing roll; comparing the measured current value to a first predetermined value; and reducing the vibrations of the screen, if the measured current exceeds the first predetermined value.

A control method of a treatment plant for elements to be recycled or disposed of, having a crushing roll to reduce the size of the elements to be recycled or disposed of, and a screen operatively arranged upstream of the crushing roll to enable passage therethrough only of elements having a size larger than a predetermined size, includes the steps of measuring the current absorbed by the crushing roll; comparing the measured current value to a first predetermined value; and reducing the vibrations of the screen, if the measured current exceeds the first predetermined value.

Methods for reducing moisture content of alkaline earth metal carbonate may include introducing alkaline earth metal carbonate having a moisture content ranging from about 0.1% by mass to about 10% by mass into a primary crusher and operating the primary crusher to obtain alkaline earth metal carbonate particles having a top cut particle size d.sub.90 of 90 microns or less. The method may also include introducing the particles into a primary grinder and operating the primary grinder to obtain reduced-size alkaline earth metal carbonate particles having a median particle size d.sub.50 of about 60 microns or less. The method may further include introducing the reduced-size particles into a classifier mill and operating the classifier mill to obtain further-reduced-size alkaline earth metal carbonate particles having a median particle size d.sub.50 of about 12 microns or less, and a moisture content of about 0.15% by mass or less.

Methods for reducing moisture content of alkaline earth metal carbonate may include introducing alkaline earth metal carbonate having a moisture content ranging from about 0.1% by mass to about 10% by mass into a primary crusher and operating the primary crusher to obtain alkaline earth metal carbonate particles having a top cut particle size d.sub.90 of 90 microns or less. The method may also include introducing the particles into a primary grinder and operating the primary grinder to obtain reduced-size alkaline earth metal carbonate particles having a median particle size d.sub.50 of about 60 microns or less. The method may further include introducing the reduced-size particles into a classifier mill and operating the classifier mill to obtain further-reduced-size alkaline earth metal carbonate particles having a median particle size d.sub.50 of about 12 microns or less, and a moisture content of about 0.15% by mass or less.

System and method for controlling the startup sequence of a roller crusher is disclosed. The roller crusher includes two generally parallel rollers that are separated by a gap where the rollers rotate in an opposite direction. During startup, the gap between the rollers is greater than the gap during normal production and a feeding arrangement is run at a speed that is lower than a normal production feed rate. The rollers are rotated at a predetermined speed that is less than the speed during normal production. Other parameters of the system are set such that material is fed over the entire length of the rollers and the no crushing force is exerted during the startup. The method and system of the present disclosure reduces the amount of stress on the rolls, frame and hydraulic system of the roller crusher.

System and method for controlling the startup sequence of a roller crusher is disclosed. The roller crusher includes two generally parallel rollers that are separated by a gap where the rollers rotate in an opposite direction. During startup, the gap between the rollers is greater than the gap during normal production and a feeding arrangement is run at a speed that is lower than a normal production feed rate. The rollers are rotated at a predetermined speed that is less than the speed during normal production. Other parameters of the system are set such that material is fed over the entire length of the rollers and the no crushing force is exerted during the startup. The method and system of the present disclosure reduces the amount of stress on the rolls, frame and hydraulic system of the roller crusher.

A device and a method for rounding a graphite material including a feeding device for feeding the graphite material to the device; a plurality of rounding tools designed to revolve while rotating, which are arranged at the outer circumference of a disc rotating about a rotational axis and in a rotational direction; at least one guide apparatus); a separating device for separating fine material and superfine material and a product outlet. Furthermore, provision is made such that a cover ring is arranged above the rounding tools.