wet ball milling vs dry ball milling | orbis machinery, llc
Everything we make use of in our day to day activities passes through a milling process. Cement used in building, the cereals we eat, toiletries, paints used in making our house presentable, and the tiles that beautifies the house we live in, all went through a milling process. A ball mill is a grinder which is used to grind, blend and mix materials like chemicals, ores, pyrotechnics, paints, mineral dressing process, paint and ceramic raw materials. Its working principle is impact and attrition. Ball milling have proved to be effective in increasing solid-state chemical reactivity and production of amorphous materials. Milling operations are carried out either wet or dry.
The difference between the result gotten from using wet and dry milling are most of the time very large. This difference is attributed to the power. The power to drive a wet ball mill is said to be 30% lesser than that of a similar dry ball mill.
Nature Of Materials
In the production of some products both wet ball and dry ball milling processes are required. The grinding of the raw mix in a cement plant, can be carried out either wet or dry but because of the nature of the cement can, grinding it has to be carried out dry.
The quality expected will be the determinant of which ball milling process to be used. For example, if pyrotechnic materials is grounded dry, it gives a product superior characteristics compared to the one which was grounded wet. The grinding of aluminium for the preparation of paint is most of the time carried out using a wet milling process since the method introduces stearic acid, or other antiflocculent
The advantages Wet ball milling has over dry milling are higher energy efficiency, lower magnitude of excess enthalpy, better heat dissipation and absence of dust formation because of the aqueous environment it is being performed.
Introduction Of Active Surface Media
Wet ball milling allows easy introduction of surface active media having to do with the reduction of the required energy for the inhibition of aggregation of fine particles. Due to wide adoption, it is only theoretically possible to introduce such material or substance in gaseous or vapour form into dry ball milling. The only practicable method of introducing substance in gaseous form is wet ball milling.
In the production of ethanol, wet ball milling is the process used, because of its versatile process. It produces more products than dry ball milling, but in terms of efficiency, capital, and operating cost, most ethanol plants in the USA prefer to use dry ball milling process. In other words, dry ball milling is cost efficient in ethanol production than wet ball milling.
With the above, you should be able to weigh which of the ball milling process is appropriate and cost efficient for your production needs.
synthesis and characterisation of advanced ball-milled al-al2o3 nanocomposites for selective laser melting - sciencedirect
High-energy ball-milling employed to synthesise Al-Al2O3 nan-composite powders.The effect of the milling and pause duration analysed.The characteristics of the composite powders examined.The effect on the powders' micro-hardness analysed.
Selective laser melting (SLM) offers significant potential for the manufacture of the advanced complex-shaped aluminium matrix composites (AMCs) used in the aerospace and automotive domains. Previous studies have indicated that advanced composite powders suitable for SLM include spherical powders with homogeneous reinforcement distribution, a particle size of <100m and good flowability (Carr index<15%); however, the production of such composite powders continues to be a challenge. Due to the intensive impacts of grinding balls, the high-energy ball-milling (HEBM) process has been employed to refine Al particles and disperse the nano Al2O3 reinforcements in the Al matrix to improve their mechanical properties. Notwithstanding, the specific characteristics of ball-milled powders for SLM and the effect of milling and pause duration on the fabrication of composite powders have not previously been investigated. The aim of this study was to synthesise Al-4vol.% Al2O3 nano-composite powders using HEBM with two different types of milling and pause combinations. The characteristics of the powders subjected to up to 20h of milling were investigated. The short milling (10min) and long pause (15min) combination provided a higher yield (66%) and narrower particle size distribution range than long milling (15min) and a short pause (5min). The nano Al2O3 reinforcements were observed to be dispersed uniformly after 20h of milling, and the measured Carr index of 13.2% indicated that the ball-milled powder offered good flowability. Vickers micro-hardness tests indicated that HEBM significantly improved the mechanical properties of the ball-milled powders.
manufacturing of aluminum flake powder from foil scrap by dry ball milling process - sciencedirect
A feasibility study for producing aluminum flake powder from aluminum foil scrap by dry ball milling under an inert argon with a few % of oxygen was carried out. It was found that the pieces of aluminum foil scrap were laminated to each other, elongated by micro-forging of the falling balls, fragmented into small pieces of foil and finally formed into flake powder, during the ball milling. A larger ball is more beneficial to the milling of aluminum foil into the flake powder due to the large impact energy during the falling of the ball. Intermediate stops during the ball milling produced a finer aluminum flake powder than non-stop milling for up to 25h due to cooling of the vial. A larger amount of stearic acid reduces friction between the foil or the balls and vial wall, thus give less milling efficiency, 3wt.% of stearic acid as additive being verified as the optimum content. The aluminum flake powder produced by the dry ball milling of aluminum foil scrap can be applied to fingerprint detection or to aerate light-weight concrete.