rotary kiln

What is a rotary kiln?

A rotary kiln is a heating furnace that rotates a cylinder (retort), supplies raw materials into the furnace (inside the retort) using a feeding device (screw feeder, etc.), and uniformly heat-treats the raw materials while stirring. Rotary kilns usually have a slight slope with respect to the horizontal, allowing raw materials to be heated while gently rotating the cylinder (retort). At Tanabe, we handle a variety of processes from low-temperature ranges to high-temperature ranges (200°C to 2500°C) in order to respond to a variety of fields. please).

Features of Rotary Kiln

A heat pattern that matches the firing needs is possible.

• Since the temperature is controlled for each zone, the heat pattern can be set according to the firing needs of the product.
  [Air cooling mechanism (option)]
  For processed objects that generate heat during the firing process, it is possible to provide stable control by installing an air cooling mechanism so that the temperature control does not overshoot.
• The heater is placed on the entire surface (360°) of the heating part, and by bringing the distance between the heater and the retort closer, the heat is transmitted evenly, the heat efficiency is good, and the design is environmentally friendly with little heat loss.

Customization considering contamination

• In order to suppress metal contamination such as Fe, it is possible to customize the processing object contact part with a special alloy such as nickel. It is a technology that can be proposed because we are confident in welding special materials.

Seal measures

• We propose seal structures that meet the processing needs of our customers. We also have dust collection and dust protection covers to prevent fine raw materials from scattering around the seal.
  [High airtight seal (optional)]
• Continuous firing in a flammable atmosphere can be achieved with a unique seal structure using carbon material (highly airtight seal patent number: Patent No. 4150368).
• The unique seal structure enables control of positive and negative pressure. Prevents powder and gas leakage against positive pressure. For negative pressure, it prevents outside air from entering the furnace.

Furnace special structure

• A special structure can be installed to block the flow of raw materials, and the time the raw materials stay in the heating zone (residence time) can be maintained.

Principle, Structure and Mechanism of Rotary Kiln Furnace

Rotary kiln production system

There are two main types of rotary kilns: batch and continuous. There are some differences between these two.

Difference in processing method

• batch type
  
  
  In a batch-type rotary kiln, the raw material (heated material) is processed in fixed-volume batches (constant amount) at a time. When raw material is fed and processing is complete, the kiln is stopped, discharged, the next batch is fed, and the process repeats.
• Continuous type
  
  
  In a continuous rotary kiln, raw material (heated material) is continuously supplied and moves continuously inside the kiln. Raw material is fed into one end of the kiln and continuously discharged from the other end, allowing processing without stopping the kiln.

The difference between production capacity and efficiency

• batch type
  Batch rotary kilns are suitable for relatively small-scale production because the amount of raw material that can be processed at one time is limited.
• Continuous type
  Continuous rotary kilns are capable of continuous feed and discharge of raw materials, so they have high production capacity and efficiency. Continuous operation ensures a constant feed flow rate, improving process stability and consistency.

Which type of rotary kiln is most suitable depends on the processing requirements and production goals (please inquire individually for details of applications and processing volumes that Tanabe can handle).

Rotary kiln heating method

There are two main differences in heating methods for rotary kilns: electric heaters and gas burners.

electric heater

Electric heaters can usually heat up to high temperatures, but it is relatively easy to control the heating rate and temperature. Another feature is that it is easy to uniformly control the temperature distribution inside the kiln. The atmosphere inside the furnace can be air (including decarbonated air), oxygen, nitrogen, argon, etc.

gas burner type

The gas burner type uses heat derived from the processed material as fuel (heat source) for the heat booster. This is an energy-saving facility that utilizes the generated waste heat as an external heat source. Superheated steam (SHS) corresponds to the furnace atmosphere.

Application example of rotary kiln by temperature range

Application example with operating temperature up to 200℃

• Drying of LiB cathode material

Application example with operating temperature up to 500℃

• Copper alloy cutting chips Washing and degreasing
• SUS, FC Cutting chips Washing/degreasing
• Special metals Cutting chips Washing/degreasing
• Cutting chips of AL alloy (AC, ADC material) Cleaning and degreasing
• Cutting chips of cast iron Cleaning and degreasing

Application example with operating temperature up to 1000℃

• LiB cathode material firing
• Sintering LiB anode material
• Firing of tungsten powder
• Catalyst/ceramic firing
• Firing magnetic material
• carbon firing

Application example with operating temperature up to 2500℃

It will be supported by the carbon heater kiln.

• Firing of carbon material
• Firing of WC raw material (tungsten carbide)
• Firing of Si-based negative electrode material

Rotary kiln product lineup

Superheated steam cleaning/degreasing system for aluminum chips (active metals)

Safely removes adhering oil and moisture from aluminum chips (active metals) that often cause fires and explosions, realizing stable operation and improved added value. View product details

Superheated steam cleaning and degreasing system for various metal chips

We propose a superheated steam system with high added value and energy saving compared to the conventional method (direct combustion type, etc.). View product details

Superheated steam type organic matter removal system for metal waste

Even if it contains waste plastic or waste with a large amount of heat, and general pretreatment (combustion type) is difficult, it can be safely treated by using the superheated steam system. View product details

Superheated steam delacquering system for aluminum cans (UBC)

Safely removes surface coatings, deposits, and organic matter from metal resources (waste and valuables). View product details

Continuous external heat rotary kiln (electric)

From small machines to mass-produced machines, we propose optimal designs that meet the needs of processing items, processing fees, ancillary equipment, installation space, etc. View product details

Medium size batch type external heat rotary kiln (electric type)

Batch-type rotary kiln is recommended for samples that require long-time firing (4 hours or more). As with the continuous rotary kiln, various atmosphere gases are inserted into the furnace and the raw material is fired while stirring. View product details

Small size batch type external heat rotary kiln (electric type)

Batch-type rotary kiln is recommended for samples that require long-time firing (4 hours or more). As with the continuous rotary kiln, various atmosphere gases are inserted into the furnace and the raw material is fired while stirring. The small tester makes it easy to evaluate the firing of small amounts of high value-added raw materials. View product details

Ancillary equipment lineup for rotary kiln

In addition to the rotary kiln itself, we propose total engineering that meets customer needs, from raw material cooling equipment after kiln discharge to exhaust gas treatment (deodorization and dust collection) equipment. In addition, we can also design and manufacture only incidental equipment, so if you have any incidental equipment you want, please contact us.

continuous rotary cooler

We provide equipment that cools the raw material discharged from the rotary kiln by thermal conduction of the cooling jacket structure. View product details

continuous screw feeder

We provide equipment that cools the raw material discharged from the rotary kiln by heat conduction in a trough with a water-cooling jacket structure. View product details

Direct combustion deodorizing furnace (burner method)

Ancillary equipment that oxidizes and decomposes odorous components contained in exhaust gas at high temperatures using a burner, etc. View product details

Flow until introduction

• Based on the customer's request, we examine the specifications and create an estimate (for raw materials that Tanabe has never handled, we conduct verification tests and proceed with the examination of the specifications).
• We propose equipment specifications and equipment costs to customers.
• If there is an order from the customer, we will start designing and manufacturing.
• If there are any changes to your order, repeat steps 1 to 3 according to the changes.
• After production is completed, the system is brought to the site, installation work is carried out, and trial operation is carried out.

Validation test

We can conduct verification tests for equipment introduction according to the customer's heat treatment needs for research and development purposes (variety improvement and next-generation powder development) or verification for rotary kiln.

Flow of testing efforts

• meeting: We will discuss the test purpose and desired conditions at the meeting.
• Test plan drafting: Based on the results of the meeting, we propose a test plan that the customer desires.
• Reflection in facility specifications: We will conduct a test in the presence of the customer. Batch method is also available.
• test run: Organize data such as temperature conditions and processing time, and evaluate the results against the plan.
• Summary of result evaluation data: The test results are reflected in the equipment specifications, and the equipment specifications are proposed.

Verification test list

After-sales service

We will enhance the outer service after delivery of the rotary kiln and contribute to the creation of the optimal operating environment for our customers.

Main after-sales service

regular maintenance
We propose the best maintenance according to the customer's shutdown period.
・Cleaning and replacing the seal part
・Soundness check of external cylinder heater
・Cleaning inside the furnace and confirming soundness
・Cleaning inside the furnace and confirming soundness
・Replacing consumables such as rollers, etc.
spare parts sales
We have various consumables and spare parts necessary for stable operation. We also offer equipment diagnosis during regular maintenance.
Support for remodeling work
We are carrying out remodeling work to realize further functions, such as remodeling the in-furnace mechanism to strengthen production capacity and change products.

FAQ

Is it possible to check the workmanship of the processed material in advance?

We have testing equipment, so we can check the workmanship. After confirming the details of the test, both companies will decide whether or not to respond.

Can we ask for a proposal for pre-process and post-process equipment?

Powder processing requires not only a rotary kiln (heating furnace) itself, but also various pre- and post-processing equipment and exhaust gas processing equipment. Therefore, we propose a variety of auxiliary equipment according to the needs of our customers.

What can the furnace atmosphere do?

Mainly air (including decarbonated air), oxygen, nitrogen, argon, and superheated steam. After consulting with us about other matters, we will decide whether or not we can respond.

Can you handle maintenance for me?

We also handle regular maintenance, spare parts sales, and remodeling work. It is also possible to support only instructors or collaborate with maintenance companies.

Do you have a track record of delivering products overseas?

We have a track record of many deliveries to Asia and Europe. We can also deliver to other countries, so please contact us.

Do you have test equipment?

We have continuous type φ300RK x 2 units (for special powder / 1 unit), continuous type φ100 x 1 unit, carbon heater kiln x 1 unit, small batch type rotary kiln (φ400), so from the verification test We can proceed.

Is it possible to make it explosion-proof?

The rotary kiln itself cannot be made explosion-proof. Explosion-proof specifications can be partially selected for instrumentation equipment, etc.

What is the maximum size of the rotary kiln?

The maximum cylinder diameter (retort diameter) is φ1,400. The processing capacity is approximately 1,900 to 2,600 L/h (reference guideline for φ1400 RK).

Up to what temperature can it handle?

If it is up to 900℃, it is possible to handle it with an electric rotary kiln. A carbon heater kiln can handle temperatures from 1,000°C to 2,500°C.

Is it possible to change the material of the retort material?

We handle SUS materials and other special alloys, so it is possible to change. However, we do not handle ceramic materials.