Kiln cooler

Types of kiln coolers

A kiln cooler is an essential part of the cement production process. It has the following types.

• Clinker grate cooler

  It is also known as a grate cooler. It uses a moving grate to discharge clinker from the kiln. Cold air moves up through the grate to cool the hot clinker.

• Tube cooler

  The tube cooler uses the principle of heat exchange. Hot clinker moves through the tubes. Air or water flows around the outside of the tubes to cool the clinker.

• Rotary cooler

  The rotary cooler moves clinker through a rotating cylinder. Cold air flows into one end of the cylinder and out the other end. It cools the clinker as it moves along.

• Air quenching cooler

  This type of cooler uses a rapid blast of air to quench and cool hot clinker quickly. It reduces the cooling time significantly.

• Water quenching cooler

  A water quenching cooler sprays water directly onto hot clinker to cool it rapidly. This method is suitable for small-scale operations.

• Cooling grate

  It is a static grate surface on which clinker spreads. Cold air moves through the grate from the bottom to the top to cool the clinker.

• Flash cooler

  A flash cooler uses a fast-moving stream of air to cool clinker rapidly. It is compact and suitable for limited space.

• Double pass cooler

  This cooler has two stages. Clinker passes through two sets of cooling grates. Each stage cools the clinker further.

• Cooling bed

  A cooling bed is a static system where clinker moves slowly on a bed-like surface. Cold air moves up from below to cool the clinker.

Designs of kiln cooler

There are several designs for kiln coolers, each having its pros and cons. The choice of design depends on the type of cement being produced, the size of the kiln, and other operational requirements. The most common designs are the grate cooler, rotary cooler, and air-suspension cooler.

• Grate cooler

  A grate cooler is also called a mechanical air cooler. It has a series of grates or plates that move in unison to push hot clinker out of the kiln. Grate coolers use a fan to blow cold air through the moving plates, which cools the clinker by convection. They are efficient at cooling large quantities of clinker quickly. They also reclaim heat energy from hot clinker to preheat raw materials. Grate coolers are suitable for large-scale cement plants with high production demands.

• Rotary cooler

  As its name suggests, the rotary cooler works like a rotary kiln. It consists of a rotating cylindrical drum inclined slightly downward. Hot clinker falls into this rotating drum, and its motion mixes the clinker with air, thus cooling it. Rotary coolers are simple and require low maintenance. They are also good at handling clinker with varying temperatures. Small to medium-sized cement plants usually use them.

• Air-suspension cooler

  Air-suspension coolers are also known as air-slide coolers or pneumatic coolers. These coolers use fast-moving air to suspend and transport hot clinker through a channel or conveyor. The fast-moving air provides enough force to lift and move the clinker, while the air also cools the clinker by convection. Air-suspension coolers are compact and need less space. They are suitable for small-scale cement plants or plants where space is a constraint.

Scenarios of kiln coolers

Coolers for kilns have various applications in different industries. These are some important applications where kiln coolers are essential.

• Cement industry

  The cement industry is a large user of rotary kiln coolers. They cool the clinker and recover heat to preheat the raw material. For example, the grate cooler and rotary cooler cool the clinker in the cement kiln and use the waste heat to preheat the raw material.

• Mineral processing

  Kiln coolers are used in the production of lime, dolomite, and other minerals. The lime shaft cooler is used in the dolomitic lime kiln to cool the lime and dolomite products.

• Ore processing

  When processing ores, kiln coolers are used to produce ores such as sulfides and phosphates. A fluid bed cooler may be used to cool the ore pellets in the ore kiln.

• Ceramics and pottery

  Kiln coolers are used in the ceramics and pottery industry to cool greenware. They are used in art and industrial pottery. The air-cooled kiln cooler cools the pottery and tiles in the kiln. This increases productivity and prevents damage to delicate ceramic materials.

• Glass manufacturing

  In glass production, kiln coolers are used to cool glass batches. The glass batch cooler is used to cool the glass mass in the cooler. This is important for shaping and reducing thermal stress in the glass.

• Food processing

  Kiln coolers are also used in food processing. For example, they are used in curing meat and fish. The cooler can be a blast cooler. It reduces the temperature of the fish and meat products. This improves food safety and extends shelf life.

• Waste treatment

  Some waste treatment processes use kiln coolers to treat hazardous waste. E.g. rotary coolers are used to treat toxic metals in hazardous waste. The coolers reduce the temperature to make the waste safe for disposal.

How to choose a kiln cooler

• Production capacity

  When choosing a cooler, matching the production capacity with the kiln's production capacity is important. The cooler should be able to meet the cooling needs of the production scale.

• Cooling method

  Decide what type of cooling method is needed. If water or ice is available, choose a water-based or ice-based cooler. For environmentally friendly options, choose air-cooled or evaporative coolers.

• Energy efficiency

  Check the energy efficiency of the cooler. Opt for coolers with energy-saving features such as frequency conversion and efficient cooling materials to reduce energy costs.

• Control system

  Look at the control system of the cooler. Choose coolers with automatic and intelligent control capabilities, allowing for automatic temperature and humidity control, thus improving cooling efficiency and convenience.

• Space and installation requirements

  Check the available space and installation requirements for the cooler. Ensure that the size of the cooler matches the available space and that the installation requirements can be met. Also, consider the ease of operation and maintenance of the cooler.

• Reliability and stability

  Choose a cooler with a reliable and stable performance. It should have a long service life and the ability to work continuously to reduce the need for maintenance and replacement costs.

• Cost

  Consider the budget and overall cost of the cooler. Besides the initial purchase cost, also consider operating costs such as energy costs and maintenance costs. Strive for a cooler that has a cost-effective performance.

Q&A

Q1: What are the benefits of using a kiln cooler?

A1: The advantages of adopting a kiln cooler include energy efficiency, increased production capacity, extended lifespan of equipment, enhanced air quality, and reduced operational costs.

Q2: How does a rotary cooler work?

A2: A rotary cooler works through the rotation of a drum combined with the introduction of cooling air or water, which cools down the hot material and makes it fall at the cooler's bottom.

Q3: What are the applications of kiln coolers?

A3: Kiln coolers are useful in industries like cement, ceramics, lime, metal, and glass manufacturing.

Q4: What should be considered when selecting a kiln cooler?

A4: While choosing a kiln cooler, factors such as the type of material being cooled, cooling requirements, space availability, energy efficiency, and maintenance should be considered.

Q5: Are kiln coolers environmentally friendly?

A5: Kiln coolers help reduce greenhouse gas emissions and conserve water, thus promoting sustainability in cooling processes.