Pole pitch of the magnetic separator magnetic separator equipment has an important role and significance

Magnetic Separator pole pitch for magnetic separator equipment has an important role and significance, although we

are talking about from the effect of the production efficiency of the magnetic separator is obvious and

, But for most who do not know much about the magnetic separation equipment, may not understand.
There's a reason, so Kefan magnetic separator manufacturers absolutely necessary to carry out the necessary

introduction to help friends want to know. Affect the magnetic separation mainly due to

Su is the magnetic field and the pole pitch practical results show that, along with the particle size of the change in

composition of the top field when the magnetic separator are different, as the particle size increases, the magnetic field

required

Intensity; With the particle size of the change in composition of the top pole magnetic separator from the type required in

the magnetic separator; as the particle size increases, also increases the pole pitch.Neodymium Arc Magnets Magnetic Separator

Where is the pole pitch in dressing production efficiency of significance? Approximately half of the pitch when in the the

factory magnetic separator for beneficiation production line equipment sorting process, but the pole pitch of the

magnetic separator,

In law is universal, magnetic separator device pitch big sharp teeth very suitable for coarse-grade mineral, very suitable

for dealing with fine particles of mineral pitch small sharp teeth.
The tines of the magnetic separator device of the appropriate matching relation, tooth spacing and the particle size of

the mineral particles to be recovered by mineral particles by magnetic force formula is derived. Tines plate

When in use, to the tooth tip of the bit assembly, should minimize the level of dislocation from the installation, Choice

stars procedure is carried out in the entire tines plate stars constituency, it is necessary to

Study and analysis of the magnetic field distribution of the selected partition.ndfeb magnet

Five major trends in the development of magnetic separator Essentials

With the domestic and foreign high-performance permanent magnetic materials research work in depth, magnetic

separation equipment industry and traditional permanent magnetic separator magnetic system and structure of the

continuous optimization, upgrade and completeness

Good, to speed up the permanent magnet separator and gradually replace the solenoid magnetic separation process. Magnetic Head Pulley

With domestic and foreign mining enterprises in automatic control technology and control technology, mining

equipment manufacturing automation level

Have been increased, and magnetic separation equipment in the field of magnetic mineral separation accuracy

requirements have become more sophisticated. At present, the development of magnetic separators five development

trends:
1, magnetic separation equipment
Taking into account the actual needs of the ore magnetic separator, processing equipment manufacturers in the ever-

expanding device processing capacity at the same time, pay more attention to the magnetic separator equipment parts

fine design

. Design of the magnetic system, the introduction of high-performance permanent magnetic materials, structural

optimization, the design of the magnetic system, adding auxiliary magnetic system, the maximum degree of reduction

of magnetic leakage, improve accuracy

The SEPARATION minerals.magnetic trapping
2, the magnetic separation equipment ownership
Magnetic separator for the current expansion of the range of applications and processing fine improved, showing the

characteristics of a strong magnetic separation, can be widely used in various fields, expanding

Large applications.
3, large-scale equipment
Increase in demand due to the rapid development of the mining industry and mineral resources production and

construction, mining equipment manufacturing industry continues to expand, in the face of common equipment is

difficult to follow

Should be the gradual expansion of mine production capacity, mining equipment manufacturer dedicated to the

research and production of large-scale magnetic separation equipment.
4, the device updates
With the development of social science and technology, high-performance permanent magnetic materials, processing

technology more and more complex, the assembly technology continues to improve as well as automation and control

technology continues to improve

And promotion, combined with the actual needs of mine production, the magnetic separation equipment to further

speed up the update.
5, Automation Equipment
Development of automation technology, industrial development, increased productivity, need to continue to strengthen

the magnetic separator automation technology required to meet the automated production of mining enterprises

The maintenance magnechuck and safety instructions

Maintenance and safety instructions
  The electromagnetic chuck shall not serious bump, so as not to undermine the accuracy, idle, wipe oiled.cylinder magnets
The electromagnetic chuck enclosure should be grounded to avoid leakage wounding
The electromagnetic chuck perform standard: JB / T 10577-2006 magnechuck.

How do we judge no magnetic force of the magnetic chuck

Encounter this problem, you must first determine the electromagnetic chuck and the machine connected

demagnetization controller is not damaged, if there is no damage, then the workpiece on magnechuck

Surface, pay attention here, to step onto the pole more than two demagnetization controller magnetization, overband magnetic separator magnetic

magnechuck If the workpiece can be sucked, such as

Fruit can not be sucked, not magnetic. General magnechuck magnetic, magnetic name tagselectromagnetic coil inside the sucker broken,

this is the most serious, it could be electromagnetic

Sucker internal wires loose, or damp, or poor contact

How to control the temperature of the permanent magnet sucker grinding?

 The design and selection of the permanent magnet sucker requirements into account, the sucker in the

corresponding frequency range, to meet the load requirements attenuation characteristics, if a filter failure

Reductions can not meet the requirements of the alerts, and can adopt multi-cascade, can be obtained higher

attenuation than a single stage, the type of filter cascade can be obtained in a wide frequency band within good

Attenuation characteristics. So, how to control the temperature of the permanent magnet sucker grinding it?Magnetic Grid
   Permanent magnet sucker grinding process is often too late to pass in the depths of the workpiece, which gather the

formation of local high temperature in the surface layer. Workpiece surface temperature is often up to 1000 (in Table

The surface layer is formed great temperature gradient (up to 600 1000 [/ mm). Permanent magnet sucker grinding the

thermal effects village workpiece surface quality and performance a great impact.

Especially when the temperature at the interface exceeds a critical value, it will cause thermal damage of the table turns

(surface oxidation, burn, residual stress buckle crack). As a result will lead to

Parts of the anti-wear performance degradation, increased sensitivity to stress corrosion, fatigue resistance

deteriorates, thereby reducing the service life and the reliability of the permanent magnet sucker Part. Furthermore,neodymium block magnets

Accumulated temperature rise of the workpiece in the permanent magnet sucker grinding cycle, often leads to the

workpiece shape accuracy error of dimensional accuracy.
   Other -, the grinding heat of grinding zone, not only affect the workpiece, but also affect the life of the permanent

magnet sucker wheel. Thus, approximately the temperature in the grinding zone on the workpiece

Distribution, study of the permanent magnet sucker grinding wheel the effective abrasive grinding zone temperature to

study the distribution characteristics of the grinding burn before and after cutting temperature, is the study of the

grinding machine

Management and improve the integrity of the important issues of the grinding surface of the part.

The extensive use of the permanent magnet sucker

Permanent magnet sucker, also known as magnetic chuck or permanent lifting, machinery factory, mold factory, forging

plant, steel mills, shipyards, steel place the necessary handling tools,

In order to greatly improve the massive, cylindrical, plate, irregular guide the conveying efficiency of the magnetic steel

material. Permanent magnet sucker is a high-performance NdFeB rare earth materials (N> 40)

Kernel,Neodymium Arc Magnets pulled by hand rotation of the suction cup handle, change the sucker internal NdFeB magnetic system, to hold

or release the suction of the need to move the workpiece.
In our machining, mold manufacturing, metallurgical and other industries, some bulky steel or iron, steel processing

accuracy requirements or surface roughness of finished or semi-finished

Goods lifting, they use a wire rope bundled lifting, or also useful for lifting electromagnet electromagnet large volume,

high cost, failure and more difficult to maintain,magnetic separation

Electromagnet at work to consume a lot of power, a power failure, accident-prone. With the advent of high-performance

NdFeB rare earth materials, the use of Nd-Fe-B permanent magnet materials

Become a trend in the development of magnetic tools, permanent magnet sucker came into being.

The following reasons causing the problems

To excessive mine sieve overload, sieve working conditions can not meet the requirements, the sieve fraction high

levels of qualified, high-frequency fine sieve plant production capacity of high-frequency fine sieve expectations are too

high, according to the production capacity of the production factory calibration or exceed its production capacity to the

mine make the problem even more serious;
   Second, to the mine site design is not quite reasonable, resulting in excessive wear and tear to the mine site,

reducing the life of the screen; screen material, but off. Should be to improve the quality of efforts to guarantee the

accuracy of direction.overband magnet

     Sorting operations Problems processing plant workers and the efforts of the manufacturers, the domestic magnetic

separation equipment made some progress, but there is a great distance away from the magnetite process. Barrel

permanent magnetic separator as a traditional magnetic separation equipment has a long history in the Concentrator,

but the product is relatively simple, it is only in a limited number of varieties limited options,magnetic drums it is difficult to do on the

different minerals different targeted, and tube-type magnetic separator in order to achieve the separation of monomer

mineral secretion effect ideal, but he kept the body powerless.

Problems and Prospects for the Development of China's magnetite beneficiation

   Magnetite iron mineral reserves in China accounted for a large proportion reached 48.8%. To identify reasonable

beneficiation process and processing equipment to deal with magnetite mine for our country and the entire steel

industry has a very important significance. In recent years, the beneficiation workers in China after unremitting efforts

magnetite beneficiation process and equipment has been greatly developed grade iron ore has been greatly improved.

The individual concentrator has reached 70%, the national average increase of more than l%; impurity content

decreased significantly, some concentrator application of a single magnetic separation silica content dropped to less

than 2%. Iron and create favorable conditions, but also the development of the mine. n52 neodymium magnets

    The following is a problem, as described below:

    The fineness of the grinding product is not reasonable dissemination size of magnetite material is very uneven,

ranging from a few microns to a few millimeters, and the same problem exists in the same mine the same ore body

brought to the processing operations difficulties. The process for the separation of magnetite Monomer to process

requirements, it will have to minimize the dissemination size as a standard for grinding, its result, part of the mineral

grinding.

       Mineral grinding mineral particles key force greater than its own inertia force, the beneficiation process becomes

not do anything, the consequences are lower concentrate grade and reduced metal recovery, the reason for the

existence of such phenomena, the following factors. (1) a single grinding equipment. Grinding equipment in China a

single species, and the concentrator can only choose several types on the market today only, nothing more than self-

mill, ball mill, rod mill. Autogenous grinding its selective grinding role beneficiation optimistic about the workers, but its

hard grind the presence of particles gave created a significant obstacle to the popularization and application. This is

because dealing with the hard grind particle crushing system to enter the restricted iron is very strict and difficult to

achieve non-ferromagnetic metal is removed, the ferromagnetic metal and difficult to separate the magnetic minerals,

stone crushing system is difficult to run, since The mill's production capacity can not be increased, can not meet the the

beneficiation production requirements, thus limiting the autogenous mill in the popularization and application of

magnetite Hill. Accurate iron removal device, and the stone crushing system to relax the restrictions on the iron

boundaries, the direction of future research.

      Beneficiation of domestic workers and equipment manufacturers in recent years, research in this area, and

received some effect. For example, the column mill has been in field trials, obtain some very important data, laying a

foundation for future research. Ball mill In addition to the specifications, the range of choice is limited. Domestic in this

area due to inadequate attention invested little beneficiation workers have no choice. The result is that only processes

to adapt to the equipment, beneficiation process can not be optimal.

     Foreign roller mill, the Aisha grinding, mixing mill, the beneficiation workers in recent years a number of studies, still

stuck in the pilot phase, to promote the application of certain difficulties because of its high cost, the real into the

beneficiation process There is no precedent. Domestic column mill in recent years developed a new grinding

equipment for mineral processing workers, such grinding equipment has its unique role in the mineral grinding, and

low cost, low cost of grinding, beneficiation workers a new idea for grinding opened up a new path. Before entering the

market in recent years, and magnetite is still in the pilot phase, the quality of its design, manufacturing precision, wear-

resistant materials, the ability of continuous operation, can be manipulated to be further improved. Its processing

power is also very small, is not conducive to large-scale production, into a study should be in large-scale equipment

clearance adaptive. Reduce the number of manual adjustment. So as to promote the application of the magnetite plant.

     (2) grinding operations to the mineral particles is too wide. The grinding process generally is a two-stage grinding

media choice is very difficult. Targeted particularly strong choice grinding media difficult to do, can not be achieved

targeted grinding, cause some mineral overground, to sorting operation caused great difficulties. Blind pursuit of short

process also contributed to this situation is an important factor. This is a misunderstanding, the direction of our

research should be increased grinding segment, to the mineral particles narrow level, the grinding medium of choice

more targeted to improve grinding efficiency by improving each piece of the overall grinding efficiency, so The

consumption does not increase.

     (3) grading operations to be further improved. Of magnetite concentrator applications grading equipment spiral

classifier, water spiral, high-frequency fine sieve. The spiral classifier most of the concentrator has been applied,

because in recent years the price of iron concentrate market to improve the grade fare increases,magnetic pulley prompting people to

pay more attention to improve the grade of iron concentrate, spiral classifier classification efficiency is low, the reverse

The shortcomings of the rich class people paid special attention, in some concentrator has been some other device

instead, will eventually be eliminated.

      Water spiral is being applied to a large number of concentrator for grading equipment, but also there are some

problems: First, the water screw machine is the use of the gravitational field classification, which requires water spiral

gravitational field is stable. Such minerals can be accurately graded, but we are now automatic control level is difficult to

do so by the a stable gravitational field, the precise classification can not be achieved within the water spiral; due to

application of misunderstanding on the water spiral mineral particles is too wide, will inevitably result in the density of

large particles with large density of small particles mixed with the same can not be accurately graded. This limits the

use and development of water conservancy spiral.

     The direction of future research should be placed on self-control, so that the gravitational field of the water spiral

remained stable. In order to make the water spiral give full play to its unique features, in order to achieve the purpose of

accurate classification. In recent years, high-frequency fine screen in the magnetite concentrator is a wide range of

applications, has played a very important role to raise iron impurity reduction. Foreign high-frequency fine sieve

structure is more reasonable, screening efficiency is relatively high, but the cost is high than the domestic many

applications in the mining less. In recent years, domestic high-frequency fine sieve manufacturer made a lot of work,

and achieved good results. Concentrator application of domestic equipment in recent years has also been a relatively

good results, but the device itself that there are some problems in the application of its advantages did not play very

well. First sieve qualified fraction content is high, the screen excessive wear and tear.

Introduction to magnetic beneficiation

Magnetic separator using various mineral magnetic differences in the magnetic field in the magnetic separator for

sorting a dressing method. Around the moving charge wins space and current surrounding space. Need most

common phenomenon in a magnetic field of two magnetic objects attract each other or mutually exclusive, suspension magnet and the

interaction between the magnets is carried out through a magnetic field. Magnetic field is energized conductor also

produced a production role, indicating the nature of the force of magnetic field when energized conductor moving in a

magnetic field. The magnetic force will be energized conductor acting, which means that the magnetic field energy. The

performance of these magnetic material.
   The magnetic field is generated by a moving charge or current. Permanent magnet generates a magnetic field, but

also because the the permanent magnet internal molecular current, so-called molecular current refers to the entire

molecule corresponding to the total magnetic effect on the outside circulating currents. If video games constant

magnetic field is constant, a constant magnetic field is called a constant magnetic field or static AIDS field.
  Said Fang Zi magnetic field strength turned the following categories:
  Magnetic line of force
  The magnetic field lines is an image showing the maps of the lines of magnetic force of the magnetic field strength,

direction, and stars in Buqian state curve permanent magnet and the solenoid the magnetic flux density indicative of the

strength of the magnetic field, the direction of the magnetic lines of force so provides: magnet The external N pole

departure, after the space into the S pole. Inside the magnet by the S pole to N pole, forming a closed curve. AIDS lines

of force in the direction is the direction of the magnetic field, the magnetic line of a point tangential direction is the

direction of the magnetic field strength of the magnetic field at that point.
    Magnetic induction
    Magnetic field on the movement of charge or current-carrying conductor stronger role. To describe the nature of the

magnetic field with the magnetic field of current-carrying wire forces physical quantity called magnetic induction.
    The breaking strength of induction size defined as follows: unit magnetic moment of the test coil in a magnetic field of

a point of maximum magnetic suffered refuse the Pm-coil magnetic moment equal to the current strength and it is

surrounded by an area of ​​the product, i.e., Pm = I So, the magnetic flux density in the practical system of units ", when

the magnetic moment of 1 [A] [m] 2 meridional, a point in the magnetic field, if it is the largest magnetic moment

[Newton] [ m], the point of the magnetic flux density of 1 Weber / m 2, pity Sri Lanka intends to (T), welding magnets tube known as a

"special". Magnetic field strength value is used to measure the physical strength of the magnetic field. Magnetic field

strength is defined as: (outer magnetic field in the magnetic medium due to render the magnetization can strengthen or

weaken the material of the magnetic field is called a magnetic medium), a magnetic field in a point of the magnetic

induction B and the same point on the magnetic permeability ratio . For the point of the magnetic field strength, which

means that the symbol H, i.e.: H = B / μ
The unit of magnetic field strength is determined as follows: In the above formula, a unit of the magnetic induction B

Weber / m 2 (Wb / MZ), the magnetic permeability μ of the unit taken of Webber / Ann meters (Wb / A. M), the magnetic

field The intensity units are ampere / meter (A / m). A / m unit is very small, in practical applications, the common unit in

amperes / cm (A / cm) and Manchester Texts (OE), the conversion between them is:
   1A / m = 10-2A/cm == 4πx 10-3Oe
    It should be understood that the magnetic field and the magnetic induction intensity is indicative of the direction of the

magnetic field and the physical strength. They are both correlated (B = uH) have the difference. Influence on the

magnetic field due to the magnetization of the magnetic medium in a magnetic field, in the case of a uniform magnetic

media, including media magnetization and the magnetic field generated by magnetic induction B. Simplex current or

moving charge in the magnetic field caused by the magnetic field strength H.
    , If placed in the type of broken media have different magnetic induction B in the case of the same magnetic field, the

magnetic field strength did not change. For example, in a magnetic field into a piece of magnetic permeability than the

air permeability μ mu. Much larger piece of iron, most of the magnetic field lines intensive iron with iron filings can

check out this change. This shows that the magnetic flux density distribution has changed, but the intensity of the

magnetic field has not changed.
   The mineral grain Why can magnetization?
   The magnetic ore particles in a magnetic field can display the magnetic phenomenon called magnetization. The

fundamental reason is the arrangement of the mineral particles inside the atomic magnetic moment at the direction of

the magnetic field. The following describes the nature of the sources of magnetic substance and magnetization.
    We know that any substance is composed of molecules, molecules are made up of atoms. Do nucleus electronic

orbital motion and spin motion, as well as the spin of the nuclei, which are the formation of micro-current. Each micro-

current quite thousands of a small current-carrying coil, so it has a magnetic moment. The magnetic moments of nuclei

by most substances are much smaller than the electron magnetic moment is negligible. The magnetic properties of

the material in the magnetic moment of the electron, the spin magnetic moment plays a major role. The magnetic

nature of the material often called unit magnetic moment (or equivalent magnetic moments of the atoms or molecules)

and magnetization to illustrate. The quality of the diamagnetic, paramagnetic and ferromagnetic qualitative difference is

due to the external magnetic field, the magnetization state of phase
The same.
     Anti-magnetic substance in the absence of an external magnetic field, the magnetic moment of the atom cancel

each other, the equivalent magnetic moment of the atom is equal to zero, no significant external magnetic substance.

When the presence of external magnetic field, the magnetic force electrons rotating around the nucleus, and its angular

momentum change, is the angular velocity of rotation will change, and thus the atoms in the microscopic current will

change the original atom the magnetic moment of the equilibrium state is compromised, there appears an unbalanced

magnetic moment per atom. According to Lenz's law, we know that the magnetic moment and the external magnetic

field of the imbalance in the opposite direction, thus weakening the external magnetic field. General diamagnetic effect

is very weak, after the removal of the external magnetic field, the diamagnetic effect squid disappeared, in fact, anti-
The magnetic effect is widespread among all substances, but some substances diamagnetic effect is overshadowed

by other factors. Diamagnetic susceptibility of the material x is negative. Anti-magnetic substance is obvious bismuth,

and others such as copper, zinc, silver, gold, mercury, antimony, sodium, graphite, and argon, nitrogen and other inert

gases, and most of the organic substances are anti-magnetic substance.
     In the atoms and molecules of paramagnetic substances, the equivalent magnetic moment is not equal to zero, the

magnetic moment of the atom has an inherent, but because of the intrinsic magnetic moment of the atom is in a state

of disorder, confusion direction of external magnetic effects cancel each other out. And therefore does not exhibit

macroscopic magnetic properties. When the external magnetic field, the intrinsic magnetic moment attempt to tend to

the direction of the external magnetic magnetic substance. In this case, we say that the substance is magnetized. Once

the external magnetic field disappears, the material will be lost magnetic, paramagnetic susceptibility of the material x

is positive. Aluminum, barium, calcium, magnesium, tungsten, titanium platinum oxygen and other paramagnetic

substances. Be seen, the inherent magnetic moments of such substances to the root causes of the magnetic effect is

generated.
   Ferromagnetic material with anti-magnetic material. Paramagnetic significant difference. Iron, cobalt, nickel, and

some of their alloys, as well as manganese and chromium alloy or the like of a class of the substance of the crystalline

state, even under a weak external magnetic field, also showed a strong magnetization of such substances called iron

magnetic substances. Internal atomic magnetic moments of the ferromagnetic substance, in the absence of an

external magnetic field under the action has been ordered in some way, i.e. to have reached a certain degree of

magnetization, this magnetization is called the spontaneous magnetization. Spontaneous magnetization into the region

in many cells in each small region, the atomic magnetic moments are then arranged in the same direction, the

spontaneous magnetization of the small area called magnetic domains. In the absence of an applied magnetic field,

the ferromagnetic material within each magnetic domain direction of the spontaneous magnetization of the same

external magnetic effect cancel each other out, and thus does not show the magnetism when the applied magnetic

field, the external magnetic field is not to make a single atomic magnetic moments steering, but each magnetic domain

magnetic moment turned to the direction of the external magnetic field. Such ferromagnetic substance in a less strong

external magnetic field is strongly magnetized, until saturation. Therefore, the presence of a magnetic domain is the

root cause of the ferromagnetic materials have a very strong magnetic effect.
    Magnetization state of magnetic solids in addition to the diamagnetic, paramagnetic and ferromagnetic so-called

ferromagnetic and ferrimagnetic not be introduced.
   From the above, the magnetization of the material is due to the external magnetic field, the material internal atomic

magnetic moments are arranged in the direction of the magnetic field. This is the source of material magnetization and

magnetic nature.

The scope of application of the magnetite mineral processing equipment

The magnetite English name magnetite iron oxide. Chemical formula: the feo Fe2O3, (i.e., Fe3O4), often vanadium,

titanium, chromium and other mixed. Isometric crystal system. Crystal mostly octahedral or rhombic dodecahedron. But

more often has a granular or massive aggregate output. Iron black. Semi-metallic luster. Opaque. The relative density

of 4.8 to 5.3. Hardness of 5.5 to 6.0. With strong magnetic. Magnetite is a very common mineral,magnetic trapping can be formed in a

variety of endogenous and metamorphism, and rich integration huge deposits. Industrial Applicability It is the main raw

material of iron-making. High purity magnetite powder is an important material in the modern electronics industry. In

gemology, magnetite is generally of great value.
Magnetite beneficiation equipment full set of equipment, the main products are: jaw crusher, hammer crusher, roll

crusher, impact crusher, vertical crusher, energy efficient cone bearing ball mill, vibrating screen, automatic anti-sand

spiral polarized machine, high efficiency flotation machine, mining stirred tank, feeder, concentrator, mine hoist, mining

conveyor, pre-water into a ball plate, spiral chute, dressing shaker, washing machine and other equipment .
The equipment and technology for crushing, the preselected throw waste, grinding, classification, magnetic separation.

The primary ball mill cone energy-saving ball mill, energy-saving effect is remarkable high production efficiency; motor magnets

magnetic separator using the new composite magnetic system, high recovery rate of complete separation; concentrate

high-frequency screening re-election, and then grinding, anti-flotation process, part of the solution thoroughly the

problem of low ore grade iron powder.

Vanadium-titanium magnetite magnetic separator

Vanadium-titanium magnetite ore belong to the late magmatic segregation deposits of ore. This type of ore on the

nature of the ore particle size embedded the bout and mineral magnetic, magnetic separation easier to handle object.

Already has a certain scale of production in our country and abroad, and there is a larger vision of development.magnetic hooks In

addition to containing magnetite ore multi useful elements associated with ilmenite and nickel vanadium drill. Gangue

minerals gabbro.
                  Panxi region in China Panzhihua metallurgical and mining company with a magnetic separation sorting

vanadium-titanium magnetite period of closed-circuit grinding and two-stage magnetic separation a sweeping

magnetic separation process in addition to recovering iron, and also in conjunction with other processing methods,

comprehensive recovery of titanium minerals and vanadium, cobalt and nickel minerals.cylinder magnets
                  Magnetic separation based magnetite ore in the production practice, often in combination with other

processing methods, used contains a composite of magnetite ore, the magnetic hematite iron ore and iron ore

roasting.