JPS60228622A - Production of charcoal powder briquette - Google Patents

Abstract

PURPOSE:To produce the charcoal briquettes which are usable in a blast furnace, electric furnace, etc. by subjecting charcoal powder alone or together with powder iron ore to pulverizing, adding and mixing of a binder, and heating by a mixer provided with a high-speed impeller then compressing and molding the mixture and adjusting the moisture of the molding. CONSTITUTION:Undersize charcoal sized <=10mm. is charged from a hopper 1 into the high-speed agitaintting mixer 2 provided with the impeller 3 and is pulverized by the impeller 3 rotating at a high speed. A binder 5 consisting of carboxymethylcellulose CMC, PVA, synthetic resin or others and water 6, if moisture is required, are added thereto and the mixture is agitated and kneaded. Heat is supplied from a heat source 8 to outside cylinder 7 of the mixer 2 and the moisture is discharged from an evacuating cylinder 9 to adjust the moisture if conversely the charcoal powder having high water absorptivity is to be used. The iron ore powder is added to the charcoal powder if necessary and the mixture composed thereof is molded to briquettes by a compression molding machine 10, a roll type molding machine 11 or a disk type molding machine 12 and the moisture and hardness of the briquettes are adjusted by a hot air drying furnace 15.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for producing charcoal powder briquettes.

[Prior art]

Currently, charcoal powder is generated as unsieved powder after charcoal is sieved at the place where it is used, or during the transportation process, but most of it is thrown away and cannot be used effectively. Generally, it is said that the amount of fine powder generated is about 15 to 2 degrees during the transportation process, and about 6 degrees at the destination after transportation, and most of it, except for a small portion, is disposed of.

Furthermore, the moisture content in charcoal is about 4 degrees when taken out of the pot, but it absorbs moisture during transportation and storage and can reach 7 to 9 degrees or even up to 30 degrees.

If the moisture content is less than 15%, it can be used as is with little effect even if mixed in a steelmaking blast furnace, but if it exceeds that, the rate of steam generation will be faster than the rate of release of evaporated moisture, and charcoal will not be used in the furnace. becomes powder, which causes furnace conditions to malfunction. Therefore, moisture management is important, but moisture absorption is an unavoidable problem because the products are transported and stored in an open state as much as possible to prevent dust explosions.

To make briquettes from fine charcoal powder, at the time when charcoal was used as fuel at home, the charcoal powder was crushed into briquettes, and a binder such as glue or sugar syrup was added to form briquettes by hand. It was hardened by natural drying and used as a heating charcoal block (tadong). However, the productivity was low and it could not be used for industrial purposes.

On the other hand, as a heating fuel, anthracite is used as the main raw material instead of charcoal powder, and clay, bentonite, glue, molasses liquid, pulp waste liquid, etc. are mixed as a binder, and the mixture is molded using a roll press molding machine. Light smoked charcoal is known.

In this case, the raw material is coal-based, has low water absorption, has a higher specific gravity than charcoal, and is not fibrous like charcoal, so its structure is dense and moldable. However, when charcoal powder is treated by the method described above, it has a moisture content of up to 30% and is soft. Conventional coal briquette binders such as medium pitch, asphalt, and bituminous binders have poor spreadability and high water absorption to coat each charcoal particle. It stutters, has poor moldability, breaks under heavy pressure, and is difficult to make into briquettes. Therefore, it is necessary to destroy the charcoal structure by crushing it with a fret mill roll.

The following steps are required to turn charcoal powder into briquettes. (1) A powerful mechanical crushing process that destroys the rough structure of charcoal; (2) A process of mixing and spreading binders with different specific gravity and time properties evenly on the surface of the charcoal particles; (3) Heating process required depending on the binder (4) Adding and removing water depending on the binder used (5) Powerful compression molding process (6) Improving the hardness of the finished product and adjusting moisture Therefore, it was not possible to briquette charcoal powder using conventional anthracite briquetting equipment.

Next, in order to thinly spread the binder on the surface of the fine charcoal particles, the surface needs to be moist as described above, but in the case of coal that does not absorb water, a moisture content of 5 to 6 inches by weight is required. However, in the case of charcoal, economic expansion of the binder cannot be expected unless it is absorbed into the interior and maintains the necessary moisture on the surface.

This adjustment cannot be made using the coal briquette method.

[Purpose of the invention]

The present invention converts fine charcoal powder, which has conventionally been discarded and not used, into briquettes of an appropriate size (-1 and by keeping the moisture content at 15 cm) to produce charcoal powder briquettes that can be used in charcoal blast furnaces and electric furnaces. The manufacturing method is provided.

[Summary of the invention]

In order to achieve the above object, the present invention has been made in accordance with Patent No. 98033.
Using the "Mixing device with high-speed stirring blades" (hereinafter referred to as -Bt mixer) of "Production method of strong briquette coal for coke and apparatus used therein" disclosed in No. 4, the conventional charcoal powder was The process necessary for manufacturing charcoal powder is simplified as much as possible, and the above steps (υ~(4)) are processed in one step, compression molding, and moisture adjustment are performed.In other words, the gist of the present invention is to simplify the steps necessary for manufacturing charcoal powder or charcoal powder. In the process of manufacturing briquettes using a mixture of iron ore powder and iron ore powder as raw materials and adding a binder to the raw materials, a mixer with high-speed stirring blades is used to crush the raw materials, add binder, mix, and heat treatment. The method for producing charcoal powder briquettes is characterized by processing a series of steps in one step, followed by compression molding and moisture adjustment.

[Structure of the invention]

Next, the present invention will be explained based on the process diagram of the present invention shown in FIG. Normally, unsieved powder or extremely fine powder of 1ON or less is charged in bulk into the raw material supply hopper 1, and then high-speed stirring K is carried out.
The charcoal is introduced into the B-nexer 2, and the charcoal is crushed by the upper and lower blades that rotate at high speed. At this time, since the particle size to be finely pulverized differs depending on the type of charcoal, this rotational speed can be arbitrarily changed by the transmission 4.

A residence time of 2 to 5 minutes in the high-speed stirring KB mixer 2 is sufficient. Next, the necessary binders include carboxy methylcellulose (CMC), polyvinyl alcohol and other synthetic resins, starch, lignin, inorganic bentonite, cement, water glass, pitch, tar, firefly, etc. alone or 2 to 4 of them. The mixed binder is supplied from the mixed binder hopper 5.

If moisture is required, it is added to the water tank 6 and the high speed stirring KB mixer 2 at the same time. Depending on the charcoal particle structure and ta, the above (1), the crushing step (2), the mixing and spreading step with the binder (3) and the heating step can be performed simultaneously.

-When the water absorption rate of charcoal is high, high-speed stirring KB<Fusa-2
Heat is supplied from a heat source supply device (steam, thermal oil, waste heat, etc.) 8 to the outer cylinder 7 of the exhaust cylinder 7, and moisture is released from the exhaust pipe 9 by indirect heating.

According to the method of the present invention, water content can be easily adjusted by adding water in the same high-speed stirring KB mixer 2 at the same time as the grinding process. In addition, excess water after spreading the binder becomes an obstacle during molding, so after sufficient spreading σ, high-speed stirring KB=? Moisture is discharged by heat from the outer cylinder 7 of the heat exchanger 2. Of course, the amount of moisture is related to the percentage of the binder used, so it is necessary to measure the moisture content of the charcoal and the moisture required by the binder in advance.

This moisture adjustment can also be done with high-speed stirring (260r/
Since the process is carried out under agitation conditions in the same container using the ITI method, the effective heat transfer area is wide and the process can be carried out effectively.

Next, the processed raw material discharged from the bottom is temporarily stored in the hottuber 10, and the compression molding machine 10. It is charged into a roll-type molding machine 11 or a desk-type molding machine 12.

As shown in Fig. 2, the roll-type molding machine 11 has a drainage groove 16 that can easily remove excess water released during compression, and the desk-type molding machine 12 has a drainage groove around the circumference of the mold, as shown in Fig. 2. 14 are provided.

Both have good compression effects.

The compression-molded briquettes are passed through a hot air drying oven 15 to adjust the moisture content and hardness of the finished product, depending on the properties of the binder used at that time. After passing through the hot air drying oven 15, the product is temporarily stored in a hopper 16 or directly transferred to a charcoal blast furnace 17. An electric furnace may be used instead of a charcoal blast furnace.

[Embodiments of the invention]

Next, examples of the present invention will be described.

Example 1 Using raw charcoal as the reference charcoal, domestic soft oak charcoal was used as the reference charcoal, and 8. Briquettes A were prepared by molding the unsieved powder, and briquettes B were prepared by changing the combination of binders, based on the above-mentioned process.

The formulation and physical properties of the binder are shown in Table 1.

Table 1 As shown in Table 1, Brichella) AB! :There is no big difference compared to standard 4 charcoal, so it can be charged into the blast furnace.
, and the water content is less than the standard (Brichella) AB.
The behavior inside the blast furnace due to moisture is excellent.

Example 2 An example in which briquettes were manufactured by simultaneously mixing raw material charcoal powder and iron ore fine powder will be described.

Brichella) C, D, and E were produced using the same process as in Example 1 and the formulations shown in Table 2 below, and the physical properties of the results are also shown in Table 2.

Table 2 As shown in Table 2, even if iron ore is mixed with charcoal powder, it can be made into briquettes according to this production method, and the strength of the briquettes is also good because iron ore powder with a heavy specific gravity is mixed.

The best mixing ratio of charcoal powder and iron ore powder is 1:1. It is also possible to replace iron ore powder with lime.Charcoal blast furnaces are characterized by the fact that the height of the furnace cannot be raised due to the weak physical strength of charcoal. On the other hand, charcoal has a higher reactivity than coke, so it is said that it is difficult to increase the size of the furnace because there is no need to raise the furnace height.

Therefore, since the effective internal volume of a normal charcoal blast furnace is 40-300 T/D8 degrees, the charcoal powder briquette according to the present invention can be used satisfactorily.

However, depending on the volume of the blast furnace used, if hot crushing of the briquettes is still required, the binder may be a thermoplastic acrylic resin, a thermosetting binder alone, or another binder. Further improvement can be achieved by combining with

〔Effect of the invention〕

As described above, according to the charcoal powder production method of the present invention, charcoal powder can be made into briquettes, which could not be achieved in the conventional coal briquette production process, by using a mixer with high-speed stirring blades and selectively using a binder. This is an extremely effective method that shortens the process and enables simple and economical production, and is a useful invention that enables effective use of charcoal powder and use in charcoal blast furnaces, electric furnaces, etc.

[Brief explanation of drawings]

FIG. 1 is a process diagram showing the manufacturing method of the present invention, FIG. 2 is a schematic diagram showing a dewatering groove of a roll-type molding machine, and FIG. 6 is a schematic diagram of a mold showing dewatering properties of a desk-type molding machine. In the figure: 1... Charcoal powder hopper, 2... High speed stirring mixer, 6... Stirring blade, 5... Binder hopper, 7... Outer cylinder, 8... Heat source supply device, 9... Exhaust pipe, 10... Compression molding machine, 11... Roll type molding machine, 12... Desk type molding machine, 16... Drain groove, 14
- Dehydration groove, 15...Hot air drying oven, 17...^furnace or electric furnace. Agent Patent Attorney Sanro Kimura

Claims (1)

[Claims] In the process of manufacturing briquettes using charcoal powder alone or a mixture of charcoal powder and iron ore powder as raw materials and adding a binder to the raw materials, a mixer with high-speed stirring blades is used to crush the raw materials and add the binder. A method for producing charcoal powder briquettes characterized by performing a series of steps of , mixing, and heat treatment in one step, followed by compression molding and moisture adjustment.