What are Poromix Additives

Poromix additives are chemicals for optimizing production of AAC. They are produced in Poland, which is the largest European market for AAC. Continuing the decades-long tradition of Polish innovation in AAC, modern chemicals are developed by PMX Labs.

The chemists have over 30 years of experience in AAC, and during this time they have gained invaluable experience with the matter. With such understanding of chemical processes and possibilities to enhance them, Poromix is designed specifically for AAC production environment. Currently there are two main types of Poromix: Poromix-H and Poromix-N. They are blends of five components, based on PCE and have been developed from chemicals for concrete industry.

Why factories use Poromix

Poromix is a useful tool in production, that can help in short perspective: with lowering cost of production, improving quality of the end product, and in long perspective: market conditions and environment.

The main benefit of Poromix is a significant water reduction in the AAC mix, and at the same time, reduction of total binders (cement and lime) to achieve products of better characteristics at a reduced cost. That is a direct chemical effect.

Besides economic benefit manufacturers also observe other benefits presented in this article.

Each AAC plant is different, as some of the raw materials are locally sourced, and there are various technologies of production. Yet main objectives are the same – to supply the market with a final product that meets the requirements and is produced cost-efficiently. If a plant can release the product with improved quality and at a lower cost – it is a major opportunity to improve the position in the market.

The market also becomes more environmentally aware and aims for sustainability and Carbon Neutrality. Cement and lime are not only costly raw materials, but they are also major sources of CO₂ emissions. A topic that in the years to come will be only more and more important, as building materials industry is under a lot of pressure to reduce its carbon footprint. Often factories look for additives because of this very simple reason.

Here are examples from PMX Labs customers, as they were experiencing various difficulties common for many factories around the world. With implementation of Poromix under guidance from PMX Labs they managed to overcome those problems, gaining substantial advantages.

Factory 1: Introducing green cement in sand-based production of AAC

The client was a factory in Eastern Europe. The headquarters required the plant to introduce lower emissions cement in the recipe, as a part of plan to become more sustainable. There was a soap-based additive used to help with the flow. After the initial trials with new cement the green cakes would not harden enough in the required time frame.  

Poromix-H replaced the soap in the mixer, as well as degreaser for aluminum. Under close guidance of PMX Labs experts, reductions were made: green cement went down by eventually 25 kg, lime by 10 kg and water by 50 kg (0,02 W/S ratio). The temperature before cutting developed higher: 86,0°C compared to 84,6°C. Cast-to-cut time in range 200-220 minutes remained stable.

The green cake after changes showed much less cracks. More homogenous structure resulted in less waste. Final dosages of Poromix-H were 1,2 kg to the mixer, and 0,2 kg to aluminum holding tank. In both cases the existing dosing systems for chemicals were used. The cost per batch was the value of 1,4 kg of Poromix-H, and the cost reduction was cement, lime and elimination of soap. Needless to say, the client made savings with each cake produced.

Later the client reported that consumption of gas in the boiler dropped by 2,9 % month-to-month, as compared with production before introducing Poromix. This is the result of less water in the green cakes and therefore in the autoclaves. It means less energy is needed to convert water to steam during the process.

The client proudly calls Poromix implementation as an important step on its way to more sustainable production.

Factory 2: Cast-to-cut time limitation on a sand-based production of AAC blocks

The client was a factory in central Europe. No additives were used in the production. It was a lime-rich formula. Cast-to-cut time was a fast 125 minutes, and due to limited amount of moulds it was of utmost importance to keep it or shorten it.

The production was very stable and controlled. There were lime spots and soft patches occurring periodically. PMX Labs conducted trials aimed to reduce the cost of the recipe. 1,2 kg of Poromix-N was introduced, together reductions of 10 kg cement, 10 kg lime and 45 kg of water (~0,015 W/S Ratio).

Thanks to better homogenization of the mass, due to Poromix preventing coagulation, quality of the green cake improved. White cakes showed less waste and better distributed pores. Reduction of costs due to 10 kg cement and 10 kg lime was greater than the cost of 1,2 kg of Poromix-N, thus every cake generated costs savings.

Couple of months later production manager of the plant made optimization of the recipe, in consultation with PMX Labs. Without increasing the production costs the curing time was shortened safely to 115 minutes, putting less pressure on the daily operations.

Currently the client is working on reducing the autoclaving time – due to less amount of water inside the cakes – to increase the overall capacity of the plant.

Factory 3: Severe sedimentation and foam on top of cakes in a sand-based production with addition of ash.

The client was a plant in Europe, part of a group. It turned to PMX Labs for help with quality issues after changing the lime supplier.

Changing a key raw material highlighted many issues the factory was just living with over the years but were not critical with the old lime.

There was a simple stabilizer used in production for many years and no one in the plant knew what its function was. The mass did not mix properly, as the sedimentation and uneven distribution of pores was clearly visible. Top part (3-5cm) of the green cake was literally foam due to extreme foaming of the stabilizer. For density 500 kg/m³, the difference in top and bottom cubes in density was up to 12%, where in compressive strength it was as high as 18%.

Soap used to degrease the alu powder when in contact with the stabilizing chemical was generating extra residues in the slurry tank.

The cake was cut horizontally, and often the soft mass at the top of the cake was generating dirt in the cross-cutting area. This often required extra care by the operators to prepare the cut top for lifting.

PMX Labs performed trials, which lead to implementing Poromix-H. The cement and water was reduced by 20 kg and 30 kg (0,015 W/S Ratio) respectively, with the additive dosage 1,0 kg. The old additive was successfully replaced, which only added to the financial benefits of introducing Poromix.

Quality gains were substantial: as the mass became more homogenous, the green cake was stronger. The foam was no longer created on the top, and the cutting process went much smoother and cleaner. The difference in top and bottom cubes was at about 4% in density and 5% in compressive strength.

The interval for cleaning of the return slurry has been extended to two years. It was reported that after the implementation of Poromix the maintenance of the slurry system was easier, and there were no stoppages in production due to improved flow of the return slurry.

These changes made also a visible impact – the blocks had much better distribution of pores, and there was less waste reported on the packing line.

Poromix trials at your plant

Every factory can potentially benefit from Poromix additive. PMX Labs offers trials of the additives to experience the possibility of optimization on-site in practice. In most cases a personal visit is organized to maximize the efforts and steepen the learning curve.