Shotcrete is a technique for applying shotcrete by wet spraying, at high speed, without dust and with minimum rejection. In the area of Refractory, this method involves the projection of refractory concrete by means of a special nozzle where compressed air is added, having been previously pumped with high performance equipment, and at the beginning of the process prepared in a mixer with the totality of its liquid.

The versatility and efficiency of Shotcrete Technology have made it the preferred option for dense refractory concrete applications in industrial equipment that require, on the one hand, refractory linings resistant to high temperatures and in extreme conditions of abrasion, erosion, corrosion and thermal shock, and on the other hand, to reduce the downtime of such equipment with a fast application of the refractory. Our experience of more than 30 years allows us to optimize the use of this Shotcrete technology to offer safe, durable, efficient and environmentally sustainable solutions. Throughout these years, we have developed and improved a proprietary system that we have patented as “Alfranjet®, to guarantee maximum efficiency, which translates into a longer service life of the installations and less downtime for our customers’ industrial equipment.

The use of shotcrete not only improves the efficiency of industrial facilities, but also contributes to process safety and sustainability. Thanks to its ability to form dense and uniform refractory coatings, it is possible to protect structures against wear and corrosion, critical factors in aggressive industrial environments. In this article, we will explore in detail what Shotcrete technology is, how we use it at Alfran and its various industrial applications.

What is shotcrete

Shotcrete is particularly valued for the ability of the refractory castables it projects to adhere to irregular and vertical surfaces, making it ideal for repairs and coatings in hard-to-reach places. In addition, precise control over the amount of mixing liquid and admixtures allows the properties of the sprayed refractory concrete to be adjusted, optimizing its strength and durability. This flexibility is crucial in applications requiring high performance, in industries such as cement, steel, non-ferrous metals, energy, oil & gas, among others.

Industrial applications of shotcrete

The applications of shotcrete in the industrial sector are wide and varied. In the cement industry, shotcrete is used to coat and/or re-lining with refractory concrete practically all the equipment involved in the manufacture of clinker, protecting these structures from wear caused by high temperatures and chemical processes.

In the steel industry, shotcrete is essential for the maintenance and repair of refractory linings in blast furnaces, reheating furnaces and converters, as well as steel maintenance and transfer equipment, where a material that can withstand extreme heat and abrasion is required.
In the aluminum industry, this technique uses refractory castables with anti-wetting properties, which minimize the formation of corundum, as well as the effects of erosion and corrosion.

In the energy industry, shotcrete applies refractory castables in boilers and combustion systems, where it provides a protective barrier against corrosion and oxidation. In addition, in the petrochemical sector, shotcrete is used to line refractory in reactors and processing units, ensuring safe and efficient operation in highly corrosive and high temperature environments.

Why and what we use shotcrete for at Alfran

With our patented alfranjet® system, nº1 in Shotcrete technology, with more than 30 years of experience and worldwide references in Cement, Iron and Steel, Energy and other industries, we offer the best solution for the installation of dense refractory concretes by wet spraying. At Alfran, we use shotcrete as a safe, efficient and effective solution for the installation and repair of refractory linings. This technique allows us to offer fast and high quality services, minimizing downtime.

The application of refractory castables by shotcrete minimizes the risk of accidents due to the reduction of the number of people involved in the installation process, with no need to lift material, as well as high performance due to its high installation speed, and minimal material losses in the process.

Our experience has taught us that each project has specific needs, so we adapt our

Refractory concrete, also known as refractory concrete, is widely used in various industries where structures or equipment must withstand high temperatures. The ability of refractory concrete to withstand extreme thermal conditions makes it indispensable for certain applications. Here are some examples:

Steel and Metallurgy Industry: Refractory concrete is commonly used in the manufacture of industrial furnaces, maintenance equipment, transfer and blast furnaces for steel production. It is used to line specific areas, providing a heat-resistant barrier that allows furnaces to reach and maintain high temperatures without damage.

Glass industry: As in metallurgy, furnaces for glass manufacturing also need to withstand high temperatures. Here, refractory concrete is used to coat and protect critical areas of the equipment.

Power Industry: In thermal and nuclear power plants, refractory concrete is used in various parts of the facility, especially those that are subject to high temperatures or corrosive conditions.

Chemical Industry: Many chemical processes require high temperatures, and refractory concrete is used to build and maintain reactors and other equipment used in these processes.

Cement Industry: Most of the equipment involved in cement production is lined with refractory concrete to protect it from the intense heat generated during the process.

The refractory concrete pumping process, which we call Pumpcrete, is used to transport the concrete from mixing to where it is needed, allowing it to be placed in areas that are difficult to access or in large volumes. Where a heat-resistant lining is required, the refractory concrete is pumped into place and then allowed to cure before the structure is subjected to high temperature conditions.

Refractory castables, also known as refractory concretes, are materials that have the ability to withstand high temperatures and pressures, in addition to having low heat transfer rates. In the cement, steel, energy, oil & gas, non-ferrous metals and glass industries, among others, these materials are crucial to achieve optimum energy efficiency.

One of the most notable benefits of refractory castables is their ability to act as excellent thermal insulators. They retain heat within the kiln, minimizing heat loss to the surrounding environment. This means that the equipment will require less energy to maintain the desired temperature.

In addition, refractory castables can withstand extremely high temperatures without decomposing or losing their properties. This is crucial in industrial equipment where very high temperatures are required in critical processes, such as metal melting or glass manufacturing.

These materials are also durable and resistant to wear and corrosion, which means they do not need to be replaced frequently. This reduces maintenance costs and downtime, which in turn improves overall equipment efficiency.

By effectively insulating heat and resisting high temperatures, refractory castables also protect other components, which could be damaged by extreme heat. This extends equipment life and reduces the need for costly repairs and downtime.

Refractory castables help maintain an even temperature distribution within the equipment. This is vital for many industrial processes that require precise temperature control to ensure consistent product quality.

These materials have excellent thermal shock resistance, which means they can withstand sudden temperature changes without cracking or weakening. This is critical in industrial equipment where temperature can fluctuate rapidly.

In addition to being thermally resistant, refractory castables also provide structural strength. This means that they can withstand heavy loads without deforming or breaking, which is crucial in the physically demanding environment.

Finally, refractory castables can be cast in a variety of shapes and sizes, allowing engineers to design systems that maximize heat efficiency. They can also be used to repair and rebuild damaged areas of the lining, extending service life.

In some cases, refractory castables can be recycled, which contributes to the overall sustainability of the production process and can reduce material costs.

One more year we celebrate our annual convention, in this case in the Aquarium of Seville, Spain. A space to share experiences and enjoy with all our colleagues from all business lines. The sense of belonging and teamwork was our common thread.

Thanks to all those who attended and to those who were unable to attend due to work.