Description:

Micronising is a process extensively used by the pharmaceutical, chemical, agro-chemical, pigment and cosmetic industries for the production offline powders.

The MEPL Micronising Mill is suitable for virtually any materials requiting ultra fine grinding, whether in campaign or continuous production. Special linings are available for cohesive and for abrasive materials. This is best suited for heat sensitive materials, because the cooling effect of grinding fluid as it expands at the jets and material remains cool.

It is possible to produce powders that are predominantly below 5micron for use in.

• Pharmaceuticals
• Organic Products
• Fine Chemicals
• Inorganic Products
• Antibiotics
• Agro chemicals
• Cosmetics
• Pigments
• Animal Health
• Dyestuffs

The Micronising Mill has many advantages over conventional comminuting equipment.

• It can produce materials of low micron size.
• The product particle shape is uniformly spherical.
• It is easy to clean.
• It can be used for hygienic/sterile applications.
• It has no moving parts.
• It operates with any compressed gas.
• Heat sensitive materials can be processed.
• If compressed hot air is used, a degree of product drying is achieved.
• Two or more material can be simultaneously micronised and blended.
• Materials can be coated.
• A wide variety of materials of construction and lining can be provided.

Feed material is inspirited by venture into the cylindrical grinding chamber of the mill. Compressed gas jets, arranged tangentially around the grinding chamber, accelerate the particles, causing omter-particulate impact in the extremely turbulent zone close to the chamber wall. Intense velocity of the jets and the fluid energy is rapidly dissipated to the particles. Larger particles are retained within the outer circulating mass by centrifugal forces, while fine particles outgoing gas stream. The combination of centrifugal and drag forces operating within the grinding chamber provides an efficient classifying mechanism. An adjustable guard ring at the center of the chamber further restricts the passage of oversize particles before material and gas pass from the chamber, either to an integral cyclone or to a separate collector.

• The Milling System consists of ONE MEPL Micronizer with a grinding chamber diameter of approximately 2”/4” / 6” / 8” / 12”/20”. This unit has all contact parts in SS 316 material of construction. It includes a set of removable PTEE liners to minimise product build up and caking.
  • Included with a Venturi based powder injection system for delivering the powder to the milling chamber. This injection system is completely removable and cleanable along with the Grinding Chamber.
  • All seals and gaskets for the above are made from silicone rubber.
• ONE Reverse Pulse Jet Filtering Chamber fabricated from polished SS 316 parts on a movable SS 304 stand. This consists of SS 316 filter bag frames and a specially designed filter bags suitable for use with the powder. These bags are continuosly dusted by a reverse pulse of air. An electronic timer with solenoid valves controls the frequency and duration of the air jet pulse.
• A powder feeding system for controlled dosing of the powder to the Jet Mill. This comprises of:
  • ONE detachable screw spiral specially designed for conveying difficult-to-flow powders. This screw is completely detachable and cleanable.
  • ONE geared Motor for driving the screw spiral in feeding the powder to the Mill. Precisely adjusting the rpm of the motor via VFD DRIVE controls feed rate of the powder.
  • ONE geared Motor for driving the Agitator Assembly inside the Product Feed Hopper for prevention of rat holing and ensures the even flow of powder into the screw spiral.
• ONE Product Collector in SS 316 with its own spring loaded trolley in SS 304. The Collector Vessel is securely fastened to the Pulse Jet Filter by Triclamps.
• This vessel further breaks down into 2 sections for ease of cleaning. The spring-loaded trolley is also completely washable.
• All powder contact surfaces of the grinding chamber, pulsejet filter and product collector are crevice-free, smooth and polished for ease of cleaning.
• A unique Vacuum Balancing System with a sight glass at both the product feeding end as well as the filtered air outlet end of the Reverse Pulse Jet outlet. This system ensures virtual SILENT running of the complete system and also prevents personnel exposure to the powder in case of blowbacks caused by some powders.
• All Piping is in SS 316 material of construction, polished on the inside and fastened with Triclamps.

1. Spare Product Collector in SS 316 with its own spring loaded trolley and Triclamp set.
2. A COMPLETE set of spares for uninterrupted operation of the unit for a period of around 2 years. (This includes one extra set of ALL sealing gasket/O-rings, ONE extra set of PTEE liners for the grinding chamber, ONE extra Venturi tube, ONE extra Grinding jet ring and ONE extra electronic timer for the Pulse Jet diaphragm valve.
3. FLP Control Panel.
4. PLC Control Panel.

An Example of one product which is micronised in microniser model MEM 200G practical distributor.

90% < 5 micron
99% < 7 micron
100% < 10 micron

Max particle size = 9 micron in general input feed size of 100 mesh with air pressure of 7.5 kg/cm2, adequate quantity of air and controlled feed gives better results. Setting of microniser also plays an important role.

However, final results can be delivered by trail. Fineness and out put depend upon material characteristics and other factors.