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Lime Slaking Mill

A horizontal ball mill can be used as in a lime slaking circuit just as well as a vertimill.

Some operations apply the raw quicklime directly to the ore on the belt moving toward further crushing or grinding. In this application, it is necessary only to have a suitable lime storage tank with a live bin bottom and a means for metering the lime from the tank to the ore. Such metering devices may be screw conveyor, belt conveyor or star valves. An activated bin bottom on the storage tank, commonly referred to as a live bin bottom, is very desirable to promote, uniform discharge from the tank. The lime is thus intimately mixed with the ore and slakes to form hydrated lime when it comes in contact with the cyanide leach solution.

When mill practice requires that the lime first be slaked and made into a water slurry, the design engineer will find a wide variety of lime slakers available. All of these reject most of the inert material in the line except the ball mill slaker which grinds the core, which then reports with the lime slurry. Because of the high reactivity of the lime available, it

VSI Crusher Vertical Shaft Impactor

In a vertical shaft impact crusher, the aggregate feed is introduced into a shoe or pump spinning on a vertical axis. The aggregate feed is thrown centrifugalLY against a series of anvils, pockets of aggregate particles (i.e., autogenous), or a combination thereof. Vertical shaft impact crushers produce a small reduction ratio and arc often used for crushing tines.china manufacturer

In hammer mills the impact of a fast-moving hammer on a slow-moving rock causes shattering. It can also be caused by the collision of a rock traveling at high velocity with another rock or a breaker plate. This is the concept of a vertical-shaft impact crusher.

vertical shaft impactor (1)


vsi crusher

vertical shaft impact crusher (1)

Vertical Shaft Impact VSI Crusher

vertical shaft impact crusher (2)

vertical shaft impactor (1)

The Vertical Shaft Impactors or VSI

Sand Washing Machine

A high quality spiral sand washing machine for you sand wash plant. china manufacturer1-year-warranty
The spiral sand washing machine (XL series) is able to wash and separate the soil and other impurities in sand and gravel aggregate. I he enclosed structure, adjustable overflow weir plate, and reliable transmission parts increase the cleaning and dehydration effect, which can be applied to road, hydraulic, and construction industries.

The main features are listed below.

  1. The structure is simple. The bearing device of impeller driving is isolated from the washing water and sand thus largely decreasing the failure rate.
  2. The loss of fine sand and stone powder in sand washing process is small. The washed sand is of good gradation; the fineness modulus can easily meet the requirements of relevant standards.
  3. Almost no components of the machine are vulnerable to wearing and breaking down except the screen.

sand washing machine (1)

sand washing machine (4) sand washing machine (2)

sand washing machine

Dense Medium Cyclone

From the early 1960’s until the mid 1980’s, dense medium cyclone circuitry design technology did not change appreciably. The basic design, which was both highly flexible and highly efficient, was consistent with technology developed by the Dutch State Mines (“DSM”) in the mid 1940’s. During this period, the “typical” dense medium cyclone circuit was designed to process raw coal in the 9.5 mm x 0.6 mm size range. Coarser coal was processed in dense medium vessels or jigs, and the fines were processed in spirals, water-only cyclones, or flotation.

The past years have witnessed a significant extension in state-of-the-art dense medium cyclone circuitry design. Dense medium cyclones are rapidly becoming a common choice for cleaning a much broader size range of raw coal than considered economically feasible just a few years ago. From a nominal top size of 63.5 mm to 76.2 mm down to 0.15 mm dense medium cyclones have been shown to be capable of operating economically and over a narrow range of efficiencies. This remarkable extension of the feed size range considered appropriate for dense medium cyclone cleaning is primarily a function of the following:

  • An improved understanding of how cyclone configuration and operating conditions (including magnetite characteristics)


Our line of cutting mills includes models which reliably process: soft, medium-hard, elastic, tough and, fibrous materials. All models are based on the same grinding geometry and feature. Depending on which model, our cutting mills may feature:

Variable speed and adjustable in a range from 700- 3000 revolutions per minute
Fixed rotational speed of 1500 revolutions per minute

This allows your mill to be adapted to different sample requirements like breaking behaviour or temperature sensitivity. Additionally our larger cutting mill features the superior rotational energy storage technology which can improve the performance of the 3 kilowatt drive to up to 20 kilowatts. When necessary the according power is provided by a flywheel. The stored rotational energy in this flywheel provides additional energy & allows for grinding even difficult material like rubber products without blockage of the rotor. Therefore larger mill succeeds even with grinding tasks which cannot be processed by other mills. Another important feature is provided by the double acting cutting bars which permit 18 cutting events per revolution thus allowing for fast size reduction process. The large cutting mill can be equipped with the optional cyclone suction combination consisting of industrial vacuum cleaner and a cyclone unit the vacuum cleaner generates an airflow that

High Performance Jaw Crusher

The 911MPEFC250 is a Fine Jaw Crusher for pre-crushing of extremely hard up to brittle materials down to < 2mm in one step:

  • End fineness 90% < 2mm
  • Very Powerful
  • Infinitely, reproducible gap adjustment
  • Easily change of jaw plates and side liner
  • Various infeed hopper: removable, with safety guard, batch loader and metering
  • External control by Start/Stop
  • Contamination free grinding

Superior Jaw Crusher engineered for pre-crushing of extremely hard up to brittle materials designed for batchwise and continuous pre-crushing of middle hard, hard brittle and tough materials for the following fine grinding.

Principle of operation
The 911MPEFC250 Jaw Crusher is used by laboratories and processing companies to crush solid materials such as rocks or soil and ores. The material to be processed falls into the crushing chamber of the LMC Crusher via a guide chute and is crushed by crushing action of a static and a dynamic jaw plate until it passes the preselected gap of the crusher.europe manufacturer

Principle of operation for fine-crushing
Unlike conventional jaw crusher, the movable crushing jaw is guided in this jaw breakers in an oscillating motion. As a result the crushing gap
remains in

Mixer Mill – High Energy Ball Mill

A Superior Mixer Mill engineered for rapid and reproducible sample preparation procedures. This High Energy Ball Mill can handle simultaneously two or more samples from 0.2 ml up to 160 ml. Grinding, Mixing and Cell disruption in on machine. This MIXER MILL is designed for “1001 laboratory applications”. Typically Processing times are between 15 and 45 seconds. This HIGH ENERGY BALL MILL can prepare 2 or more samples from 0.2ml up to 160ml. It is designed as well for high-sample throughput.europe manufacturer

All Static Mixers, have some helical mixing element which directs the flow of material radial toward the pipe walls and back to the centre. Additional velocity reversal and flow division results from combining alternating right- and left-hand elements, thus increasing mixing efficiency. All material is continuously and completely mixed, eliminating radial gradients in temperature, velocity and material composition.mixer mill


  • Universal and highly efficient, blending and disruption
  • Large range of grinding jars and accessories
  • Large range of grinding balls and accessories
  • Extremely short processing times
  • Designed for high sample throughput
  • Reproducible results by digital pre-setting of all working parameters

Air Jet Sieving Machine

The 911MPE Air Jet Sieving Machine is a powerful aspiration unit with variable throughput of 0-99 mBar ensures that the material is quickly dispersed and can pass the test sieve.

The aspiration unit is equipped with an automatic cleaning system for the filter. This allows that many sieving procedures can be done before replacing the cartridge.

An Air Jet Sieving Machine is used for particle test separation of powder and dry substances. The machine is designed to work with test sieves in the range of 5 and 4000µm.

The Air Jet Sieving Machine includes the following parts:

  • Air Jet Sieving Machine
  • Aspiration unit
  • Plexi lid
  • Filter cartridge
  • 5 Plastic bags
  • Rubber mallet

The Air Jet Sieving Machine 911MPELMAJ 200 is designed to handle materials which tend to agglomerate like pharmaceuticals, pigments and for sample materials with a low density. Sieving aids like sieving brushes, sieving balls and cubes which support the sieving process are available as well.
alpine air jet sieve principle

LAARMANN air jet test sieves are delivered with an external sealing from sieve to sieving machine by a special rubber – adapter ring. sieving-machines-test-sieves-air-jet-test


[pdf-embedder url=”https://www.911metallurgist.com/wp-content/uploads/2018/10/CK0.2-USER-MANUAL.pdf” title=”ck0.2 user manual”]

Comminution Model Types

Many types of mathematical models are used in comminution and mineral processing.  These models can generally be classified into one or more of the four categories shown above.

Mill Power Draw Models

The purpose of a mill power draw model is to predict what the mill power and/or torque draw will be for a mill of a certain geometry containing a specified charge being tumbled at a specified rotation rate.  These models are used be designers to select mill and motor combinations for new plant designs, and are used by operators to “benchmark” the operation of an existing mill.  An operating mill that draws power equal to or exceeding the model is generally a healthy mill.

Examples used in industry (and example software I am aware of):

  • Morrell C-model (JK SimMet & SAGMILLING.COM) and E-model
  • Austin SAG model (SAGMILLING.COM)
  • Hogg & Fuerstenau (MolyCop Tools)
  • Nordberg model (SAGDesign and SAGMILLING.COM)2018-08-10_1608

Specific Energy Models

The purpose of specific energy models is to predict how much grinding energy is required to break a particular rock down to a specified size.  A single size category, typically 80% passing, is used in order to simplify the equations.  These models are also used

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