What are the 5 steps in gypsum production?

The production of gypsum typically involves several steps, including mining, crushing, grinding, calcination, and drying. Here are the five steps in gypsum production:

Link to wuxing

1.Mining: Gypsum is extracted from underground or open-pit mines. In underground mining, shafts or tunnels are dug into the earth to reach the gypsum deposits. Open-pit mining involves the removal of overlying soil and rock to access the gypsum. The extracted gypsum is usually in the form of large chunks or layers.

2.Crushing: The extracted gypsum is transported to a crushing facility where it is crushed into smaller pieces. This crushing process helps to break down the gypsum into manageable sizes and prepare it for further processing.

3.Grinding: The crushed gypsum is then transported to a grinding mill, where it is pulverized into a fine powder. The grinding process involves the use of mechanical forces to break down the gypsum particles and reduce them to a desired fineness. This powdered gypsum is often referred to as land plaster or stucco.

4.Calcination: The ground gypsum powder is subjected to a process called calcination. Calcination involves heating the gypsum at high temperatures (around 150-165 degrees Celsius or 300-350 degrees Fahrenheit) in order to remove the water of crystallization from the gypsum and convert it into a different chemical form known as calcium sulfate hemihydrate, also known as plaster of Paris.

5.Drying: After calcination, the gypsum product is in the form of calcium sulfate hemihydrate, which still contains a small amount of water. The product is dried in a specialized drying chamber or kiln to remove the remaining moisture, resulting in the final product known as commercial gypsum or drywall gypsum.

It's worth noting that the specific production processes may vary depending on the equipment and technology used by different gypsum manufacturers.

The present invention relates to the phosphogypsum is the method for raw material producing building terra alba, relates in particular to a kind of high potassium/sodium phosphogypsum with the phosphoric acid by wet process by-product and be the method that raw material, preparation can be used for producing the building gypsum plaster of Thistle board.

Phosphogypsum is washed pre-treatment, can make the alkalimetal ion of solubility such as potassium, sodium ion enter water, by water slurry cyclonic separation, filtration, remove the alkalimetal ion of the solubility of the overwhelming majority, potassium sodium ions content in the phosphogypsum is reduced, the sticking paper problem that the phosphogypsum that can solve high potassium/sodium content is used for Thistle board when producing.But it is long that the characteristics of this technology are flow process, investment is big, the washing cost is higher, and bring the difficult problem in the wastewater treatment after the washing, the free water content of the phosphogypsum dihydrate after washing increases simultaneously, gypsum frying to follow-up workshop section is unfavorable, directly causes the increase of phosphogypsum frying energy consumption, and cost rises thereupon.Because the problems referred to above, make that the high potassium/sodium phosphogypsum is difficult to be used as the raw materials for production of Thistle board.

For more Gypsum powder grinding machineinformation, please contact us. We will provide professional answers.

The by product phosphogypsum of phosphoric acid by wet process is a quantity discharged maximum in the chemical gypsum.Dihydrate gypsum content generally about 80&#;90%, is higher than the common commodity plaster of paris in the phosphogypsum, can be used as the substitute of the plaster of paris.The ordinary method that with the phosphogypsum is raw material system Thistle board at present mainly comprises phosphogypsum producing building terra alba, two steps of building gypsum plaster system Thistle board, that is: at first the phosphogypsum frying is become the required raw material of Thistle board--building gypsum plaster by the frying production line, again by the Paper-faced gyp board assembly line with building gypsum plaster mix with amidin, paster moulding, drying become Thistle board.Because phosphorus ore quality difference, the foreign matter content in institute's by-product phosphogypsum is closely not identical yet, and alkali metal ion content measured such as potassium, sodium are higher in the phosphogypsum that has, K in phosphogypsum 2 O, Na 2 The O gross weight reaches 0.1% (butt) when above, ion migration can take place in high-load potassium sodium in the drying process of Thistle board, produce " scum " phenomenon in gypsum board surface, cause cardboard to separate, make plasterboard only form waste product because lose sticking paper function.Therefore, this high potassium/sodium phosphogypsum usually can not be directly as the raw material of making Thistle board.

Summary of the invention

In order to solve the not sticking paper problem that above-mentioned high potassium/sodium phosphogypsum exists as Thistle board, the invention provides a kind of method that can be used for the high potassium/sodium phosphogypsum producing building terra alba of Thistle board, can suppress the migration of potassium sodium ion with its Thistle board of making, effectively prevent to produce " scum " phenomenon in gypsum board surface, and less investment, technology is simple, and running cost is low.

The inventive method is achieved in that at K 2O, Na 2The O total content reaches and adds potassium sodium inhibitor C aCO in the phosphogypsum raw material more than 0.1% of phosphogypsum butt weight 3Or CaCO 3With the mixture of CaO, to the pH of gained target product in 4.0&#;5.5 scopes, through broken mixing, ageing, make required building gypsum plaster with ordinary method again.

The inventor finds in experiment, adds CaCO in the high potassium/sodium phosphogypsum 3Or CaCO 3With the mixture of CaO, the potassium sodium ion there is the obvious suppression effect.It suppresses mechanism and has two kinds: a kind of CaCO of being 3Or CaCO 3With after the adding of CaO with phosphogypsum in H 2SiF 6Reaction causes a large amount of SiO 2Separate out,, thereby prevent that it from separating out because the viscosity of SiO2 adsorbs the potassium sodium ion; Another kind is building gypsum plaster pH in 4.0&#;5.5 scopes the time, and the potassium in the phosphogypsum, sodium ion may be with Na 2SiF 6, K 2SiF 6Form exists, and Na 2SiF 6, KSiF 6Solubleness lower, therefore, potassium, sodium ion mainly exist with insoluble salt form and can not separate out in this case, the sticking paper of the Thistle board that the building gypsum plaster of gained is produced is functional, sticking paper rate can reach more than 98%.Therefore, with CaCO 3Or CaCO 3With CaO as potassium sodium inhibitor, not only can suppress separating out of potassium sodium, can also improve simultaneously the pH value of phosphogypsum, solvable phosphorus in the elimination phosphogypsum, solvable fluorine are to the disadvantageous effect of plaster of Paris material, method therefor is simple, processing cost is low.

Because pH is in 4.5&#;5.0 scopes the time, Na 2SiF 6, K 2SiF 6Solubleness minimum.Therefore, add potassium sodium inhibitor when the pH of building gypsum plaster is in 4.5&#;5.0 scopes, best to the restraining effect of potassium sodium, the paper phenomenon can cannot not appear stickingly in the Thistle board of the building gypsum plaster production of gained.

SiO 2The amount of separating out is many more, and the effect that suppresses potassium sodium is good more.But CaO is a strong basicity, and big to the pH value influence of phosphogypsum, add-on is too much unsuitable, otherwise causes the pH value fluctuation of phosphogypsum excessive easily.And CaCO 3Little to phosphogypsum pH value influence, but add-on is crossed the strength degradation that conference causes the building gypsum plaster that makes.Therefore, used CaCO 3Be advisable with 1:0.3&#;0.5 with the weight ratio of CaO.

Starting point of the present invention is not lie in how to reduce the potassium sodium ions content of bringing in the Thistle board, but by selecting for use suitable inhibitor to suppress the migration of potassium sodium ion, solve " scum " phenomenon of gypsum board surface, used treatment process technology is simple, less investment, easy to operate, running cost is lower, and can not bring the waste water handling problem of washing process.

Contact us to discuss your requirements of Gypsum powder processing plant. Our experienced sales team can help you identify the options that best suit your needs.