This disclosure may generally relate to drilling operations and, more particularly, to systems and methods for cleaning a drilling fluid as it travels back to the surface from a wellbore. An apparatus may comprise a magnetic body having a longitudinal axis. The magnetic body may comprise a pair of end plates that are spaced along the longitudinal axis and a magnetic unit disposed between the pair of end plates, wherein the magnetic unit is operable to generate a magnetic field. The apparatus may additionally comprise an axle disposed along a longitudinal axis of the magnetic body, wherein the axle is operable to rotate the magnetic body about the longitudinal axis.

A defibrating device and sheet manufacturing apparatus attract and remove metal fragments when metal fragments are mixed with fibrous material. A defibrating device has a main unit with a defibration section configured to defibrate fibrous material, and a swirl section configured to produce a rotational current, and by the rotational current cause the fibrous material to rotate and flow into the defibration section. The main unit has a magnet unit that is disposed to the swirl section, and has a magnet that attracts by magnetic force metal fragments conveyed with the fibrous material to the swirl section.

A defibrating device and sheet manufacturing apparatus attract and remove metal fragments when metal fragments are mixed with fibrous material. A defibrating device has a main unit with a defibration section configured to defibrate fibrous material, and a swirl section configured to produce a rotational current, and by the rotational current cause the fibrous material to rotate and flow into the defibration section. The main unit has a magnet unit that is disposed to the swirl section, and has a magnet that attracts by magnetic force metal fragments conveyed with the fibrous material to the swirl section.

A magnetic particle separating valve that includes a valve body adapted for allowing particulate matter to flow vertically through the valve from an upstream to a downstream side. A discharge flow control apparatus is positioned in the valve body and includes a plurality of blades positioned in the valve body and movable between a fully open to a fully closed position to control the rate of discharge of material from the valve. Each of the plurality of blades includes a magnet positioned on the respective blade in a flow proximity position to attract and remove magnetically attractable particles from the particulate matter flowing past the blades.

A magnetic particle separating valve that includes a valve body adapted for allowing particulate matter to flow vertically through the valve from an upstream to a downstream side. A discharge flow control apparatus is positioned in the valve body and includes a plurality of blades positioned in the valve body and movable between a fully open to a fully closed position to control the rate of discharge of material from the valve. Each of the plurality of blades includes a magnet positioned on the respective blade in a flow proximity position to attract and remove magnetically attractable particles from the particulate matter flowing past the blades.

Provided are a natural graphite, a modified natural graphite material prepared therefrom, a preparation method, and applications. The natural graphite has the following characteristics: a particle size D50 smaller than 10 m, and D90/D10<2.5; a 002 interplanar spacing ranging from 0.336 to 0.360 nm, I.sub.002/I.sub.11035; a saturated tap density greater than or equal to 0.6 g/cc and smaller than 1.3 g/cc; and a specific surface area greater than or equal to 1.0 m.sup.2/g and smaller than 10.0 m.sup.2/g. The provided natural graphite has specific particle size, orientation, tap density and surface area and can serve as a raw material for preparing modified natural graphite material, and the prepared modified natural graphite material has high isotropy and thus has better rate performance and cycle performance.

A ferro-magnetic material recovery system includes a drum rotating within a magnet housing. An array of magnets mounted within the magnet housing have corresponding magnetic fields which decrease in strength in the direction of rotation of the drum to extract the material from a slurry flowing through the drum. Flow deflectors may be mounted in the drum. The array of magnets may form a magnetic core having magnetic fields that are radially aligned.

A ferro-magnetic material recovery system includes a drum rotating within a magnet housing. An array of magnets mounted within the magnet housing have corresponding magnetic fields which decrease in strength in the direction of rotation of the drum to extract the material from a slurry flowing through the drum. Flow deflectors may be mounted in the drum. The array of magnets may form a magnetic core having magnetic fields that are radially aligned.

A ferro-magnetic material recovery system includes a drum rotating within a magnet housing. An array of magnets mounted within the magnet housing have corresponding magnetic fields which decrease in strength in the direction of rotation of the drum to extract the material from a slurry flowing through the drum. Flow deflectors may be mounted in the drum. The array of magnets may form a magnetic core having magnetic fields that are radially aligned.

A ferro-magnetic material recovery system includes a drum rotating within a magnet housing. An array of magnets mounted within the magnet housing have corresponding magnetic fields which decrease in strength in the direction of rotation of the drum to extract the material from a slurry flowing through the drum. Flow deflectors may be mounted in the drum. The array of magnets may form a magnetic core having magnetic fields that are radially aligned.