A brief introduction to the clay dryer
Because clay is buried deep underground for a long time, it contains few grains of sand and it is difficult for water to pass through it. Therefore, it needs to be dried and dehydrated to ensure that its final moisture content is below 0.5-1% before it can be applied to industrial production on a large scale.
Clay moisture content for industrial production
What types of clay can be processed by clay dryer and what are they used for?
Kaolin
Kaolin (china clay) is a mixture of hydrous aluminosilicates composed of various minerals, the basic components of which are clay minerals such as kaolinite group, halloysite, a small amount of montmorillonite group and hydromica.
The proportion of kaolin in ceramic industrial ingredients is generally 20-50%, some products are up to 80% and some electric porcelains are 100%.
In the paper industry, kaolin is used as fillers and coatings, which can improve the density, whiteness and smoothness of paper surface, reduce transparency and ensure better absorption of color.
In the rubber industry, kaolin is used as fillers. It is the reinforcing filler that can improve the mechanical strength and acid resistance of rubber, reduce the cost of products and is an important raw material in refractory equipment.
Kaolin is also used in dyes, plastics, paints, automobiles, white cement, enamel, agriculture, medicine, soap, clay masks, textiles, and other industries such as defense and atomic energy.
Earthenware
Earthenware is mainly composed of kaolinite, hydromuscovite, montmorillonite, quartz and feldspar. Its particle size is inconsistent, often containing sand, silt and clay.
It has the characteristics of absorption and plasticity after adding water. The sintering temperature of earthenware is lower than 1250℃, belonging to low-fire clay.
Its sintering range is wide, generally between 80℃–100℃. The earthenware is mainly used for firing exterior walls, floor tiles, pottery wares and so on.
Fire clay
Fire clay refers to clay that can be used as refractory materials and bauxite used as refractory materials with refractoriness greater than 1580℃.
In addition to their high fire resistance, they can maintain volume stability under high temperature and have slag resistance, rapid cooling and heat resistance, and certain mechanical strength, so they are extremely firm after calcination.
Fire clay applications in the metallurgical industry
As the raw material for the production of shaped refractory materials and unshaped refractory materials, the consumption of fire clay accounts for about 70% of all refractory materials. The hard clay is used to make blast furnace refractory materials, iron-fining furnaces, hot air furnaces, lining bricks of ladles and filling bricks.
Fire clay applications of clay brick
Fire clay applications in building material industry
Fire clay is used to make high-alumina brick, phosphate high-alumina fire brick and high-aluminium fused cast brick for cement kilns and glass melting furnaces.
The high-alumina clay can be made to aluminium-containing cement after calcination and mixture with limestone, which has the characteristics of rapid hardening, corrosion resistance and thermal resistance.
Fire clay applications in building material industry
Fire clay applications in the grinding industry, chemical industry and ceramic industry
High-alumina clay can be melted in an electric-arc furnace to produce abrasive materials, of which fused corundum abrasive is the most widely used one at present, accounting for 2/3 of all abrasive products.
In the ceramic industry, hard clay and semi-hard clay can be used as raw materials for making daily-use ceramics, architectural ceramics and industrial ceramics.
High alumina clay is used in oil wells as a proppant to purify petroleum; as a fertilizer promoter in agriculture; and paving materials for skid and abrasion resistance, etc. Hard clay is also used to make a new type of refractory and thermal insulation material—refractory fibre.
Ball clay
Ball clay is an aluminosilicate sedimentary mineral with strong plasticity and fine particle size (smaller than fireclay and kaolin), which is easy to disperse in water and coexistent with lignite.
The ball clay has various colors, mainly black and gray. After roasting, it is soft and sticky and shows white, yellow, ochre, etc. according to its impurity content. It is an important binding clay in the ceramic industry.
With good adhesion, ball clay is often used in refractory materials, such as dense clay bricks, high-quality alumina bricks, mullite products, corundum products, chrome corundum slide gate bricks, silicon carbide products and refractory sets.
Stoneware
The firing temperature of the stoneware can be as low as 1160℃ and as high as 1350℃ according to the content of its flux. It is characterized by rigidity and high mechanical strength.
The stoneware body is fine and dense with low porosity and the water absorption rate less than 6%. Stoneware is commonly found in industrial acid-resistant chemical ceramics, architectural ceramics, domestic stoneware and furnishings.
Performance advantages of FTM Machinery clay dryer
1 Drying effect: The clay dryer not only adopts multi-combined lifting plates, but also have a new internal structure that strengthens the cleaning and heat conduction of the dispersed materials, reduces the adhesion phenomenon of the inner cylinder wall.
Performance advantages of FTM Machinery clay dryer
2 Heat transfer process: In the process of drying material, due to the high airflow velocity, the entire surface of the material can be taken as the effective drying area, in addition to the dispersion and stirring action during the drying period, the heat transfer process of drying is stronger and more efficient.
3 Environmental protection effect: The complete system of industrial rotary clay dryer has strong tightness and is equipped with a perfect dust removal device, so there is no dust overflow and the operating environment is better.
Working principle of clay dryer
1 The wet material is sent to the hopper by the belt conveyor or bucket elevator and then enters the feeding end through the charger of the hopper. The slope of the feeding pipe should be larger than the natural inclination, so that the clay can flow into the dryer smoothly.
2 The dryer cylinder is a rotating cylinder that is slightly tilted from the horizontal. The material is added from the higher end, the heat carrier enters from the lower end and comes into contact as a countercurrent. Sometimes heat carrier and the material flow into the cylinder together and move to the lower end under the action of gravity as the cylinder rotates.
Working principle of clay dryer
3 The shovelling plate is installed on the inner wall of the barrel, which is used to lift up the clay and spread it to increase the contact surface between the clay and the airflow, so as to improve the drying rate and promote the progress of the clay.
4 During the forward movement of the wet clay in the cylinder, it can directly or indirectly get the heat from the heat carrier, so that it can be dried and then sent out by the belt conveyor or spiral conveyor at the discharging end.
5 After the heat carrier passes through the dryer, a cyclone dust collector is generally needed to capture the materials carried in the gas. If it is necessary to further reduce the dust content of the exhaust gas, it should also be discharged after passing through the bag filter or hydro filter.
Component configuration of FTM Machinery clay dryer
1 Cylinder: The interior of the cylinder is made of wear-resistant material with long service life. Moreover, the cylinder is designed into inclined, which is conducive to drying clay and effective use of thermal energy.
FTM Machinery clay dryer
2 Lifting plate: The multi-combination lifting plate can evenly spread the clay in the barrel, allowing the clay to fully contact with the internal heat of the dryer, improving the drying efficiency and reducing energy consumption.
3 Sealing ring: The sealing structure can effectively reduce dust overflow and noise impact, which can improve the manual operation environment.
4 Motor: The brand motor with long service life is adopted. It can guarantee the use time of the clay dryer and the production will not be affected due to the power supply.
Successful customer cases of FTM Machinery clay dryer
5 TPH kaolin dryer in Indonesia
5 TPH kaolin dryer in Indonesia
| Model | Φ1.5×14 |
| Material | Kaolin |
| Capacity | 5.3–6.6 t/h |
| Main Motor | 15 kW |
| Weight | 19.7 t |
15 TPH bentonite dryer in India
15 TPH bentonite dryer in India
| Model | Φ2.4×14 |
| Material | Bentonite |
| Capacity | 13.5–16.9 t/h |
| Main Motor | 37 kW |
| Weight | 45 t |
25 TPH earthenware dryer in Pakistan
25 TPH earthenware dryer in Pakistan
| Model | Φ2.6×24 |
| Material | Earthenware |
| Capacity | 27.2–34.0 t/h |
| Main Motor | 55 kW |
| Weight | 73 t |
30 TPH ball dryer in the USA
30 TPH ball dryer in the USA
| Model | Φ3.0×20 |
| Material | Ball clay |
| Capacity | 30.1–37.7 t/h |
| Main Motor | 75 kW |
| Weight | 85 t |
FAQ about briquetting machines
What are the differences between sand and clay?
The sand particles are large and not easy to stick together. Sandy soil refers to soil with a high content of sand, which can hardly provide nutrients for plants.
Clay contains few sand particles and is sticky, so water cannot easily pass through it. In addition to aluminium, clay also contains small amounts of magnesium, iron, sodium, potassium and calcium, so it can provide nutrients for plants.
How much does the clay shrink when it dries?
Different types of clay have different drying shrinkage rates.
The drying shrinkage of kaolin is generally 3–10% (the higher the content of halloysite in kaolin, the higher the drying shrinkage rate); the montmorillonite clay is 12%–23%. The finer the clay particle size, the greater the drying shrinkage.
What are the advantages and disadvantages of clay bricks?
The advantages of clay bricks:
① Better thermal stability than silicon bricks and magnesium bricks.
② After drying, the qualified fireclay brick for blast furnace can be impregnated with phosphoric acid in a vacuum and then fired at low temperature, which can be used for the lining of the blast furnace body.
③ Clay bricks are made locally, cheap, durable, and have the advantages of fire prevention, heat insulation and moisture absorption.
④ Waste and broken clay bricks can also be used as aggregates for concrete.
The disadvantages of clay bricks:
① Large self-weight. The structure needs to bear greater self-weight, so the project cost increases.
② Poor sound insulation. Because of its small porosity, the sound cannot be isolated and the decibel reduction of the sound is very small.
③ Damage of the environment. Because clay bricks are mainly made by burning the excavated soil, it destroys the soil and vegetation.
What to do if the clay has high humidity and is difficult to dry?
Properly increase the length to diameter ratio of the clay dryer to prolong the residence time of the clay in the dryer.
It is difficult to meet the requirements by using one form of lifting plate, so a combined lifting plate is needed.
How to reduce waste dust from clay dryer?
Ensure that the dryer has a certain negative pressure and the high-temperature gas generated by the boiling furnace is inhaled into the dryer in time, so that it can quickly exchange heat with the dried clay and be eliminated in time. Reduce the exhaust gas temperature in the dryer as much as possible to achieve rapid drying.
In the current use of dryer equipment, the dust collectors that we often use are divided into two categories: cyclone dust collectors and bag dust collectors. Pay attention to the air volume of the dust collector.
Parameter
|
Spec./m
(Dia.×Length) |
Shell Cubage
(m³) |
Capacity
(t/h) |
Installation
Obliquity (%) |
Highest Inlet
Air Temperature (℃) |
Main Motor
(kw) |
Weight
(t) |
|
Φ1.2×8.0
|
9.0
|
1.9～2.4
|
3～5
|
700～800
|
7.5
|
9
|
|
Φ1.2×10
|
11.3
|
2.4～3.0
|
3～5
|
700～800
|
7.5
|
11
|
|
Φ1.5×12
|
21.2
|
4.5～5.7
|
3～5
|
700～800
|
15
|
18.5
|
|
Φ1.5×14
|
24.7
|
5.3～6.6
|
3～5
|
700～800
|
15
|
19.7
|
|
Φ1.5×15
|
26.5
|
5.7～7.1
|
3～5
|
700～800
|
15
|
20.5
|
|
Φ1.8×12
|
30.5
|
6.5～8.1
|
3～5
|
700～800
|
18.5
|
21.5
|
|
Φ1.8×14
|
35.6
|
7.6～9.5
|
3～5
|
700～800
|
18.5
|
23
|
|
Φ2.2×12
|
45.6
|
9.7～12.2
|
3～5
|
700～800
|
22
|
33.5
|
|
Φ2.2×14
|
53.2
|
11.4～14.2
|
3～5
|
700～800
|
22
|
36
|
|
Φ2.2×16
|
60.8
|
13.0～16.2
|
3～5
|
700～800
|
22
|
38
|
|
Φ2.4×14
|
63.3
|
13.5～16.9
|
3～5
|
700～800
|
37
|
45
|
|
Φ2.4×18
|
81.4
|
17.4～21.7
|
3～5
|
700～800
|
37
|
49
|
|
Φ2.4×20
|
90.4
|
19.3～24.1
|
3～5
|
700～800
|
45
|
54
|
|
Φ2.4×22
|
99.5
|
21.2～26.5
|
3～5
|
700～800
|
45
|
58
|
|
Φ2.6×24
|
127.4
|
27.2～34.0
|
3～5
|
700～800
|
55
|
73
|
|
Φ3.0×20
|
141.3
|
30.1～37.7
|
3～5
|
700～800
|
75
|
85
|
|
Φ3.0×25
|
176.6
|
37.7～47.1
|
3～5
|
700～800
|
75
|
95
|
|
Φ3.2×25
|
201
|
42.9～53.6
|
3～5
|
700～800
|
90
|
110
|
|
Φ3.6×28
|
285
|
60.8～76.0
|
3～5
|
700～800
|
160
|
135
|
Technical parameters of indirect heat dryer:
| Shell diameter ×shell Length Items |
Inside diameter of outer shell (mm) |
Inside diameter of inner shell (mm) |
Shell Length (m) |
Shell cubage (m³) |
Shell obliquity |
Lifting blade form |
Highest inlet air temperature (℃) |
Dimensions (m) |
| Φ1.5×15m | 1500 | 500 | 15 | 20.27 | 3-5% | Lifting form | 850 | 16.2×2.7×2.7 |
| Φ1.5×17m | 17 | 22.97 | 18.2×2.7×2.7 | |||||
| Φ1.5×19m | 19 | 25.68 | 20.0×2.9×2.9 | |||||
| Φ1.8×21m | 1800 | 650 | 21 | 35.91 | 3-5% | Lifting form | 850 | 22.5×2.7×2.7 |
| Φ1.8×23m | 23 | 39.33 | 24.5×2.9×2.9 | |||||
| Φ1.8×25m | 25 | 42.75 | 26.5×2.9×2.9 | |||||
| Φ2.2×21m | 2200 | 800 | 21 | 58.10 | 3-5% | Lifting form | 850 | ---- |
| Φ2.2×23m | 23 | 63.61 | ||||||
| Φ2.2×25m | 25 | 69.15 |
|
Spec./m
(Dia.×Length) |
Shell Cubage
(m³) |
Capacity
(t/h) |
|
Φ1.2×8.0
|
9.0
|
1.9～2.4
|
|
Φ1.2×10
|
11.3
|
2.4～3.0
|
|
Φ1.5×12
|
21.2
|
4.5～5.7
|
|
Φ1.5×14
|
24.7
|
5.3～6.6
|
|
Φ1.5×15
|
26.5
|
5.7～7.1
|
|
Φ1.8×12
|
30.5
|
6.5～8.1
|
|
Φ1.8×14
|
35.6
|
7.6～9.5
|
|
Φ2.2×12
|
45.6
|
9.7～12.2
|
|
Φ2.2×14
|
53.2
|
11.4～14.2
|
|
Φ2.2×16
|
60.8
|
13.0～16.2
|
|
Φ2.4×14
|
63.3
|
13.5～16.9
|
|
Φ2.4×18
|
81.4
|
17.4～21.7
|
|
Φ2.4×20
|
90.4
|
19.3～24.1
|
|
Φ2.4×22
|
99.5
|
21.2～26.5
|
|
Φ2.6×24
|
127.4
|
27.2～34.0
|
|
Φ3.0×20
|
141.3
|
30.1～37.7
|
|
Φ3.0×25
|
176.6
|
37.7～47.1
|
|
Φ3.2×25
|
201
|
42.9～53.6
|
|
Φ3.6×28
|
285
|
60.8～76.0
|
Technical parameters of indirect heat dryer:
| Shell diameter ×shell Length Items |
Inside diameter of outer shell (mm) |
Inside diameter of inner shell (mm) |
Shell cubage (m³) |
| Φ1.5×15m | 1500 | 500 | 20.27 |
| Φ1.5×17m | 22.97 | ||
| Φ1.5×19m | 25.68 | ||
| Φ1.8×21m | 1800 | 650 | 35.91 |
| Φ1.8×23m | 39.33 | ||
| Φ1.8×25m | 42.75 | ||
| Φ2.2×21m | 2200 | 800 | 58.10 |
| Φ2.2×23m | 63.61 | ||
| Φ2.2×25m | 69.15 |