Concrete Mixers: What is Green Concrete?



You may be aware that concrete has devastating impacts on the environment but not know that there is an alternative option. Green concrete is an environmentally friendly concrete that you can use for your concrete projects. Read through our answers to common questions about green concrete and see how you can mix green concrete in your BS Commercial Power concrete mixers.


BS Commercial Power Concrete Mixers:


B&S Commercial Power is a supplier of Baumax concrete mixers. B&S Commercial Power has selectively chosen Baumax due to the ease of use, safety, and power of these concrete mixers.


There are four Baumax concrete mixers available at B&S Commercial Power.


400L Concrete Mixer with Baumax Engine: This concrete mixer produces an estimated 200L of mixed concrete.


Baumax BS500 500L Concrete Mixer fitted with Baumax RX200 2:1 Engine: An estimated 280L of mixed concrete is produced in this concrete mixer. If you require large amounts of mixed concrete in a quick frame of time, this is the concrete mixer for you.


400L Concrete Mixer with B&S Engine: Mixed concrete estimate is 220L in this concrete mixer. Despite being the same drum size as the 400L concrete mixer with Baumax engine, this concrete mixer produces a greater amount of mixed concrete.


Baumax BS360L Concrete Mixer fitted with Baumax RX200 2:1 Engine: This is our smallest concrete mixer drum, but still produces an impressive estimated 200L of mixed concrete.


The Baumax concrete mixers available at B&S Commercial Power are typically used for mixing conventional concrete in the construction industry. Our quick guide on green concrete will demonstrate how concrete mixers can also be used to mix green concrete.




Common Questions About Green Concrete:


We have answered the common questions around green concrete and shown step-by-step how you can use your BS Commercial Power concrete mixers to mix green concrete.


1) What is Green Concrete?


Green concrete, or eco-concrete, is an environmentally friendly alternative to conventional concrete.


The concept of green concrete was first introduced in Denmark in 1998 by Dr. WG. Dr. WG believed in turning the construction industry’s attention towards the by-products and waste generated within the industry. Rather than continuing the creation of waste, green concrete uses waste by-products in a better way.


Green concrete includes either the partial or complete replacement of cement and mined aggregates with recycled waste materials. To create green concrete, alternative forms of cement and aggregate are used.


Typical cement alternative materials used in green concrete are fly ash, silica fume, and ground granulated blast furnace slag. These are all by-products of other production processes.


Silica fume, for example, is a by-product in the production of silicon metal. Silicon metal is commonly used for the manufacturing of steel, microchips, and solar cells. Rather than discarding this waste, green concrete offers a greener solution.


Aggregates used in green concrete included broken concrete, waste plastic, mining and quarrying waste, slag, power plant waste, and foundry sand. The use of these waste by-products as aggregates in green concrete is an environmentally-friendly solution.




2) What is the Need for Green Concrete?


Conventional concrete is a mixture of manufactured cement, water, and mined aggregates. Conventional concrete has severe environmental implications as a result of the manufacturing and transporting of cement.


The manufacturing of cement results in carbon dioxide emissions. Carbon dioxide emissions are one of the major contributors to global warming. Climate change, acid rain, and health problems are but a few of the negative impacts carbon dioxide emissions are having on the planet and humans. Every step in the cement manufacturing process contributes carbon dioxide into the atmosphere.


Limestone is the most important ingredient in cement, and limestone needs to be mined. The mining process requires a wide use of heavy machineries, such as enormous drills and trucks. These machines require extreme amounts of energy to extract and move the limestone. This energy is usually sourced from the burning of fossil fuels, such as oil, coal, or gas, and this then results in carbon dioxide emissions.


The limestone, and other additional substances, are then ground down in large roller mills to create a raw mix. The raw mix is then moved through various extreme heating stages in a kiln. The heating is needed to cause chemical reactions in the raw mix to create clinker. Carbon dioxide is emitted during the process of heating the kiln and during the chemical reactions of the raw mix.




The clinker, which is the stony residue from the heated raw mix, is then moved through a chamber where huge fans are used to cool the clinker. The clinker is then ground down in huge machines into a fine powder and gypsum is typically added. The cooling and grinding processes to achieve the end product of cement require huge amounts of energy.


The cement will then be transported to smaller suppliers or distributed across the world. Due to the high demand for cement, numerous trucks and trains are used to transport the cement and thus include the burning of fossil fuels.


Concrete is the backbone of the construction industry and is, therefore, one of the most used materials in the world. To reduce the environmental impacts of concrete, there is a critical need for an environmentally friendly alternative. Green concrete provides a viable solution to reduce the environmental impacts generated by the concrete industry.


3) How Does Green Concrete Compare to Ordinary Concrete?


From a material perspective, green concrete and conventional concrete are equal in comparison.


Cement is used in conventional concrete as a binding agent and is critical to strong, durable concrete. The cement alternatives used in green concrete are pozzolanic materials.


Pozzolanic materials refer to materials that chemically react with water to form a cementitious material. This demonstrates that the environmentally friendly alternatives react in the same way as conventional cement.


Mined aggregates are used in conventional concrete to provide structure, volume, and stability. As long as the recycled by-products used as the aggregate in green concrete are clean, non-porous, strong, and durable, they will work equally well as mined aggregates.




4) What are Green Concrete Advantages?


There are numerous advantages to using green concrete in construction projects.


Reduced Carbon Dioxide Emissions: The use of by-products as the pozzolanic material to create green concrete means that you are avoiding the direct carbon emissions generated in the production of cement.


Recycling: Green concrete provides a viable use for by-products that would have previously been deemed trash.


A Solution to Waste Disposal: A common problem in the construction industry is the disposal of demolition waste. Green concrete provides a solution to the waste as it can be used as aggregates.


Cheaper: The use of by-products in green concrete means significantly reduced material costs.


Reduces Cement Demands: Whether you create complete or partially green concrete, you are reducing your cement demands. Lower demand reduces cement production which will then reduce carbon dioxide emissions from the concrete industry.


Lower Shrinkage Rate: Green concrete has been tested to show that it has a lower shrinkage rate compared to conventional concrete.


Easier Workability: Green concrete materials are easier to work and move compared to conventional concrete materials.




5) What are Green Concrete Disadvantages?


There are also disadvantages to green concrete.


High Water Absorption: Green concrete tends to absorb more water than conventional concrete. Water absorption can lead to cracks and failures in concrete. We recommend treating all green concrete with water-repelling sealers.


Lower Split Tensile Strength: Concrete split tensile strength refers to the concrete’s ability to withstand extreme weight or pressure. Green concrete split tensile strength is lower and thus will often need extra reinforcement.


Limited Availability in South Africa: Currently, there are only a few companies that sell green concrete in South Africa. One of these companies is AfriSam in collaboration with Concrete Laser Flooring.


Stainless Steel Reinforcement: The choice reinforcement for green concrete is typically stainless steel. This can add additional costs to your concrete project.


6) Can I Mix Green Concrete in my Concrete Mixers?


Green concrete can be mixed in your B&S Commercial Power concrete mixers. Simply follow the same method as mixing conventional concrete but replace the conventional concrete materials with green concrete materials. We have created a step-by-step method for creating green concrete in your concrete mixers.


Choose Your Concrete Mixer: Explore the variety of concrete mixers available at B&S Commercial Power and select a drum size that will suit the scale of your construction project.


Personal Protective Equipment: Before you start using your concrete mixers, you need to put on your personal protective equipment. Baumax concrete mixers have features that ensure your safety, but we recommend wearing goggles, a face mask, and work gloves whilst operating the concrete mixer.


Add Water: Pour the correct quantity of water into the drum of your concrete mixers. It is important to bear in mind that different green concrete materials require different water ratios.


Add Green Cement: Turn on your concrete mixers and slowly add in your chosen green cement. Pouring the green cement powder slowly avoids any large lumps landing into your concrete mixer. To overcome certain disadvantages of green concrete, you can supplement a percentage of your green cement alternative with conventional cement.


Add Aggregates: Add your selected green aggregates into your concrete mixers.


Pour Concrete: Once your concrete mixers have completed mixing, you are then able to pour your concrete.




About BS Commercial Power:


BS Commercial Power is a Cape Town-based equipment supplier. B&S Commercial Power stocks a wide range of power tools, such as concrete mixers. Whether you need power tools for professional or at-home use, B&S Commercial Power has all your needs covered.


B&S Commercial Power imports a range of power tools. Imported power tool brands include Honda, Briggs and Stratton, Stihl, Husqvarna, and Baumax. These brands are placed on B&S Commercial Power’s shelves due to their reputability, reliability, and quality.


Alongside importing, B&S Commercial Power also manufactures a range of robust power tools. This ensures that you have a wide variety of choices when it comes to finding the best-suited power tool for your project.


We can supply power tools to the whole of South Africa and a range of other Southern African countries. B&S Commercial Power is driven to ensure every individual and company have access to high-performance power tools to ensure every project is done well.


If you ever feel uncertain as to which B&S Commercial Power tools are right for your requirements, we will happily help. Our team has years of experience to ensure that we can always offer you support. At B&S Commercial Power, you will receive a personalised service.


Give green concrete a try for your next concrete project and mix your green concrete in one of B&S Commercial Power’s concrete mixers.