Why wash out fresh concrete? Important reasons

Here they come again, the concrete mixers, their drums still full of liquid concrete residue… and now? The goal is ambitious: 100 percent of valuable cement water and residual concrete should be returned to the water and production cycle. The same applies to recycled concrete. But where to put the cleaning water – down the drain? Not allowed – and not necessary either. Because it’s 2025: intelligent concrete recycling takes care of everything related to recycled concrete and cement water. After the fresh concrete has been washed out, resources such as aggregates, wash water and process water are returned to concrete production – in compliance with all legal requirements.

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What do you gain by washing out concrete?

In the race for the most economical production of ready-mixed concrete and precast elements, the winner is whoever reduces the consumption of extra cement and fresh water as well as landfill and wastewater costs to an absolute minimum. Efficient concrete washers essentially do two things: when washing out fresh concrete from truck mixers, mixing plants, concrete buckets and concrete pumps, concrete recycling separates sand, gravel and water for later reuse of aggregates.

Residual water is recycled into process water and environmentally friendly rinsing water as part of a closed water cycle. The range of possible systems is broad, as they can be tailored to any intake volume and other individual requirements – from one cubic metre to 25 cubic metres of residual concrete per hour. A good system delivers high washing performance with minimal wear and low energy consumption due to its design.

What happens in your residual concrete recycling plant?

All processes run fully automatically, with an interface showing the operating status of the system. In addition to continuous interval operation, fresh concrete can also be washed out in manual mode – giving you full control over each individual component. Is there a problem? The system will alert you acoustically, visually and/or via an app. A text message on the display will tell you exactly what is going on.

Let’s get started: You transport your material as effectively as possible into the washing machine of the recycling plant, for example using a scoop wheel. This means that you can also transport material at ground level or below ground level instead of only from above or from the side via a table – for example, because you want to clean concrete pumps or small equipment. But now the concrete is in the washing trough, and rotating elements transport it towards the discharge side. Solid and liquid are separated by means of a discharge screw: counter-current sends the water to the other side; fine particles that float up are removed.

The result is thoroughly washed mixed gravel with a precise separation cut, so that only particles measuring 0.2 to 0.3 mm and smaller remain in the water. This is a value that should not only be stated in the data sheet for your residual concrete recycling plant, but is also a factual production reality. However, this is only guaranteed if you respect the capacity limits of your system!

Planning concrete recycling: What distinguishes machines and processes?

In order to manage concrete return and concrete washing in a first-class manner, residual concrete washers are required that are characterised by

– robust, low-maintenance design

– High separation accuracy

– Ease of use

– Functioning in confined spaces

– Immediate operational readiness

– Insulation, heating for winter operation

– Compliance with current environmental regulations

as well as seamless integration into existing systems.

Fully hot-dip galvanised recycling plants in a rotating trough design consisting of two half-shells, made for immense washing water volumes and large quantities of concrete, mortar or anhydrite material in the shortest possible time – up to 25 cubic metres per hour. The associated container with agitator usually holds twice as much. In combination with a spiral conveyor, discharge heights of well over two metres can be achieved. When two truck mixers arrive, two flushing gallows start working in parallel.

Additional accessories such as dosing buffers for simultaneous residual concrete collection from up to six mixer trucks or a particle separator for separating fibres from fibre concrete and much more round off the options. Are you responsible for a medium to large ready-mixed concrete plant with more than five mixer trucks that is bursting at the seams during peak times? Then this type of investment is worthwhile – galvanised or painted in the RAL colour of your choice.

Wash out fresh concrete and reuse the water: here’s how!

Back with water and dry aggregates from 0.2 to 32 mm in the cycle, for new concrete! Completely dewatered by filter presses, what remains – the filter cake – is professionally disposed of as construction waste. After the fresh concrete has been washed out, only the finest particles under 0.2 mm remain in the residual water tank, kept in suspension by an agitator. Water that is waiting to be used as additive water for recycled concrete in accordance with DIN EN 1008. Provided it qualifies for customised concrete! Ensuring this is the task of treatment plants, which continuously check and adjust the water density.

Modern residual water recycling automatically determines the residual water density (in kg/l) 24/7. Like the patented AJF cement-water treatment plant CWAS with intelligent control technology, which ensures a consistently low residual water density all year round – based on the principle of water density standardisation. Further details on the reuse of aggregates and residual water additives can be found in the “Guideline for the production of concrete using residual water, residual concrete and residual mortar” (German Committee for Reinforced Concrete).

Conclusion: Environmentally conscious use of resources pays off!

Washing out and recycling concrete? It works perfectly if the plant and design are right. Investing in residual concrete recycling pays for itself quickly – and the savings are measurable. The more precise the system and the more tailored the plant is to requirements, the more residual concrete water and aggregates return to the cycle.

No more expensive, environmentally harmful additions of cement and fresh water, with high disposal costs for sediment waste! And no, you don’t have to win sustainability awards like London-based Byrne Bros. But who knows? Maybe you’ll soon be shining with the Concrete Sustainability Council (CSC) Gold Certificate – a global seal of approval for environmentally, socially and economically responsible business practices.

The article Washing out concrete, managing resources efficiently first appeared on Fresh concrete recycling begins with AJF.

What can a concrete recycling plant do?

A long day is coming to an end: time to wash out the truck mixers – and each one still contains a fair amount of concrete gold. Smart residual concrete recycling ensures that nothing goes to waste. The size of the concrete plant or construction site is secondary. Innovative processing has everything you need to get started right on the spot. Such as a low-maintenance screw conveyor that adapts flexibly to requirements. Or a feed table that is precisely matched in design and size to the largest ready-mixed concrete plant. Because modern concrete recycling as an overall concept covers everything that is continuously produced – from rinse water full of solids and active cement components to the residual concrete itself. Reusing process water saves expensive fresh water – and recycling residual concrete saves valuable primary raw materials. Here, solids return directly to the material flow and mixing plant; coarser aggregates are strategically sorted out. What remains then ends up, in the best case, as filter cake – for reuse or proper disposal.

Separate, clarify, dewater, neutralise – tailor-made!

Concrete recycling plants operate according to the counterflow principle (flotation), capable of washing out sand and aggregates from 0.2 to 32 mm, so that only the finest (cement) particles up to 0.2 mm remain in the residual water. This is called a separation cut, and should not only be stated in the machine’s data sheet, but should also be the case in reality! This is because residual concrete recycling only works where a plant is operated in accordance with its capacity. If you overload your system, the separation cut is no longer guaranteed. In other words, your complete concrete washing solution should match the required capacity in every element – and everything should be compatible with each other. A pleasant side effect: the reuse of your raw materials can now be planned!

What results are achieved by residual concrete recycling and water treatment?

Depending on individual requirements, additional level and density probes, pumps and agitators complete the concrete recycling process, ready to convey between 8 and 25 cubic metres of residual concrete per hour, depending on the size of the plant, and cover all areas of precast concrete and ready-mixed concrete production. The goal: sand and gravel aggregates that are as dry as possible and perfectly washed, achieved by means of a screw conveyor or an ascending vibration and dewatering trough. Once the residual cement water has passed through the plant, it flows into the agitator tank and is pumped back into the mixing plant. Industrial water treatment – such as that provided by AJF technology – continuously and precisely determines its solids content. This ensures that residual water always returns to the cycle at a constant, exact density. If everything runs smoothly, your residual concrete recycling plant will produce perfectly separated raw materials and a lot of valuable, dry material for fresh concrete.

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Recovery systems: How does a recycling screw work?

Low-wear and low-maintenance recycling screws (type RS6 or RS8) for the ready-mixed concrete industry do their job in the smallest of spaces, in many sizes and designs, with drive motors of varying strengths, screw lengths and screw diameters. With a sophisticated spiral arrangement, they are equipped with wear-resistant wash-out paddles; and a central lubrication system extends their service life. Let’s get started: feed the concrete recycling plant via the feed hopper from any angle. Do you collect residual concrete from the mixing plant cleaning process with a wheel loader? A practical wheel loader feeding device makes the work easier. Overfilling the plant? Don’t worry, because the shape and dimensions of the feed hopper prevent this – and the solids discharge height allows for a considerable storage volume. The washout screw prepares everything with a separation cut of 0.2 to 0.3 mm. Every hour, the screw carries away an impressive number of cubic metres of residual concrete solids with solid grain sizes of up to around 35 mm.

Need to clear away huge volumes quickly? Your trough thinks big.

Sometimes the intake and washing water volume is particularly large, meaning that considerable quantities have to be handled at very short intervals. Individually configured recycling plants with high washing capacity can handle even that! Everything, from residual water basins to the number of truck mixers to concrete pumps and engines, is designed on a larger scale. Trough and drum recycling plants are available in lengths of around 6,000 mm, and the solids discharge heights guarantee impressive storage volumes. Feed hoppers measuring 1,100 x 4,000 mm and with a capacity of 25 cubic metres per hour are not uncommon. Anything that handles this much material needs effective wear protection: if the screw shaft is positioned at a well-designed distance in the housing, a material bed can build up, minimising wear. A residual concrete recycling plant in trough or drum design saves time: at peak times, you can feed the plant from two truck mixers simultaneously, in one go, thanks to extra-wide feed hoppers. Modern washing plants can be optionally equipped with a scoop wheel for washing concrete pumps.

Out with the leftover concrete! Almost as if by magic…

The new residual concrete recycling systems also reduce personnel costs thanks to fully automatic control of all components: when truck mixers or concrete pumps approach, the flushing concrete washer starts via a sensor on the gallows – and uses recovered residual water. Residual concrete flows continuously into the inlet hopper; the screw conveyor transports gravel and coarse sand towards the discharge opening. Once a cycle is complete, the screw stops. The gallows, pump and agitators of this residual concrete recycling plant operate automatically after a pre-selected period of time has elapsed.

Considering purchasing a concrete recycling plant? Here’s what you should look out for

A good residual concrete recycling plant is versatile – whether it’s concrete with unbroken aggregates such as natural sand and round grain, broken aggregates such as crushed sand and grit, or completely new types of aggregates. Ready-mix concrete, precast elements, bridge construction, traffic areas, private house construction? Impermeable, high-strength, self-compacting, light or heavy? Innovative residual concrete recycling is part of sustainable, demand-oriented concrete production, in the form of mobile mixing plants for small to large projects. Sophisticated, economical concrete recycling is characterised by

– Flexible product customisation, on-time implementation

– Clear operation, intelligent control

– Needs-based concept comprising equipment and accessories

– Planning, production, assembly and commissioning from a single source

– Solutions for minimal wear and easy maintenance

How do construction companies and concrete manufacturers benefit?

Firstly, stationary or mobile recycling systems for concrete, process water and waste water are good for the environment: state-of-the-art environmental technology ensures the complete reuse of residual concrete and wash water produced on a daily basis – for sustainable material handling, from mixing plants to concrete pumps and truck mixers. Secondly, a residual concrete recycling plant gives you the opportunity to thoroughly clean gravel and sand, but also to reuse cement water in your operations – in a predictable, precise and economical manner. AJF has been designing and manufacturing resource-saving processing plants for the concrete industry for many years. Get started with us: clever concrete recycling is a well-rounded solution that benefits both the environment and your budget. Everyone wins!

The article Why recycling residual concrete is now worthwhile for you first appeared on Fresh concrete recycling begins with AJF.

Work quickly, use resources sparingly

For Godel and its subsidiary Godel-Rohstoffe, which operate in the ready-mixed concrete, gravel, sand and metallurgical cement segments, the careful, energy-saving use of resources is a matter close to their hearts. A pioneer in the field of innovative concrete mixing plants, the company based in the middle Neckar region stands for selected raw materials. And it knows that whether it’s a large-scale project or a private house build, every delay makes the project more expensive. Clever equipment now saves Godel time and disposal costs when dealing with concrete slurry. The new AJF water treatment plant not only guarantees a consistently low residual water density, it also meets all environmental requirements.

Return concrete and water back into the cycle

If you want to make concrete production cheaper, you have to save cement. Unfortunately, a large proportion of the more than 47 million cubic metres of concrete produced annually in the UK ends up on the inside wall of the mixer drum. That is why the new approach is to reuse the resulting concrete residues and concrete recycling water for production. What does this require? A treatment plant that continuously determines the solid content. The more precise this is, the more residual water returns to the cycle at a constant density. In the battle for precise residual water density, Godel has discovered industrial water treatment – through AJF Technologie from Egg an der Günz, Unterallgäu.

Customised concrete, EN 1008 specifications fully met

The challenge: Excess residual water usually causes (disposal) problems. And anyone who adds cement to achieve a certain quality and component strength and compensates for fluctuations in residual water density is pursuing an expensive strategy that is not very environmentally friendly. According to the Ready-Mixed Concrete Association, the production of 1 tonne of cement generates around 550 kg of CO2. With the AJF system, Godel will in future meet the EN 1008:2002 requirements for the use of recycled concrete water, benefit from density measurement in terms of precisely tailored concrete quality – and distribute the recycled water in a cement-saving and environmentally friendly manner throughout daily production. AJF’s patented CWAS with intelligent control technology ensures a consistently low recycled water density in accordance with DIN EN 1008 – fully automatically, all year round, even in winter.

Water density standardisation

AJF water treatment continuously measures density, with values immediately fed into production control. The key feature is water density standardisation: Godel simply selects the desired water density of the residual water, while complying with all water specification parameters. The modular concept of cement-water treatment is tailored in every detail to the company, capacity and plant location – from residual water basins to cisterns. Coupled with sensors, CWAS makes every task easier, whether it’s probe control or retrieval of (wastewater) values. Once the maximum density value has been recorded, it is reduced by targeted sediment removal or the addition of fresh water. Sediments and cement water no longer have to be disposed of at great expense. Godel reuses them in the production of very high-quality concrete – and saves many litres of fresh water per cubic metre.

Objective: Maximise potential savings in cement

Godel had long since figured out which constant density achieved the best strength. And because Godel already uses computer-assisted project management in all its plants, it was time to use a fully automated solution in water treatment as well – and the Bavarian company AJF had just the thing. Given the company’s requirements, Godel had very specific wishes for the new concrete technology plant: please maximise the potential savings in cement and CO2. Zacharias Funk, Head of Maintenance, sets up and dismantles the concrete plants: “The AJF plant helps us enormously in our daily handling of concrete slurry – and it is very reliable. We use it for about 16 hours a day. Additional cement added to the concrete recipe? No longer necessary, because perfect mixing water now ensures key properties of concrete quality such as setting time and compressive strength.”

Excellent conditions for cost-effective concrete and relaxed working

But AJF’s winter-proof cement water treatment plant is ideal for Godel for another reason: Godel transports the raw materials for its innovative concrete mixes using mobile concrete mixing plants, with delivery and conveying coming from a single source. Godel develops its own concrete mixes and market innovations for many projects.
Owner Stephan Godel is passionate about tailor-made concrete construction solutions. The optimal location for a mixing plant is one that saves on raw material and transport costs while keeping CO2 emissions low. Patrick Schäffler, Head of Building Materials Technology in Ready-Mix Concrete Quality Assurance, is responsible for this – and Wladimir Blehm, Head of Scheduling and a long-standing member of the Godel team, delivers the concrete to the customer. Every AJF plant arrives pre-assembled so that the concrete producer can get started right away with plug & play.

From Lidl to Zeiss – Godel makes it happen

A lot has happened since Godel-Beton built its first mobile mixing plant for large-scale projects in the Stuttgart area in 1997: Godel-Rohstoffe now produces innovative, sustainable aggregates and binders. Godel Transportbeton has also been present in Poland for over twenty years – and in 2017 it conquered the Philippine market with concrete for Manila’s metro system. In 2018, Godel was involved in the construction of Lidl Germany’s headquarters, where space for 1,500 employees had to be created on 130,000 square metres in a very short construction period. No sooner said than done: the mobile mixing plant with a 3.3 m3 mixer delivered the required total concrete volume of approximately 145,000 cubic metres. At Zeiss, on the other hand, precision was the main motto: in spring 2024, Zeiss Hightech Jena needed floor slabs with specific vibration properties – a prerequisite for Zeiss production machines to work precisely even in the nanometre range. Large-scale concreting that could not be interrupted in order to avoid the risk of unevenness during hardening.

Sustainable travel

Godel-Beton stands for over three decades of high-quality concrete, delivered quickly and precisely to meet your needs – for building construction and civil engineering, large construction sites, and private house building. A third of the more than thirty locations are even CSC Gold certified, including the supply chain. CSC stands for Concrete Sustainability Council and is a seal of approval for ecologically, socially and economically responsible business practices in the raw materials, cement and concrete industry – right down to the electric concrete mixer. Godel is rather proud of this and welcomes school classes to construction sites such as Stuttgart 21 to inspire the civil engineers of the future. Godel and innovative AJF water treatment are a perfect match – together on the path to successful smart sustainability.

The article AJF water treatment plant for Godel Beton first appeared on Fresh concrete recycling begins with AJF.

Mobile water treatment plant for industry: The principle

Regardless of the industry: a fully automated, mobile water treatment plant for the

Industry, and specifically your concrete plant, saves water, disposal costs and time – while also complying with all water protection and environmental regulations. This also reduces the load on downstream wastewater treatment plants. As a concrete plant, you benefit from a closed water cycle thanks to mobile water treatment for concrete.

CWAS, a cement residue water treatment plant for the concrete industry, treats your concrete residue water so that you can reuse it for fresh concrete production. This is because 100 per cent of its components are returned to the raw material cycle. Everything you need is housed in a special container. Completely prefabricated, equipped according to individual requirements – and ready for immediate commissioning upon arrival at the construction site.

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Whether it's fresh concrete recycling, residual water treatment, or process water management, we will find the optimal solution for your plant.

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Where is mobile water treatment for concrete at its best?

For concrete mixing plants and mixing supervisors, a mobile water treatment plant for industry means improved working conditions. Innovative cement residual water treatment achieves high concrete quality even with low water consumption and concrete slurry quantities. Mixer cleaning is also no longer carried out with expensive fresh water, but with recycled water. AJF offers you systems as plug & play products, transportable, flexible treatment systems with the appropriate water treatment technology components for construction water and waste water – even directly on the construction site.

It doesn’t take much: just stable ground, clear access roads and electricity. Mobile water treatment for concrete can be set up almost anywhere in a space-saving manner and put into operation at short notice.

A mobile water treatment plant for industrial use purifies irrigation, washing and pit water so that it meets the official requirements for process and waste water; the costs for construction site operation are reduced through recirculating water purification. Mobile water treatment plants have a wide range of applications.

On large construction sites, concrete is often produced centrally and pumped to the place of use via pipe systems. Flushing these pipes continuously produces dirty water – water treatment filters out residual substances directly.

Mobile water treatment reimagined – with the mo-BAT from AJF

A mobile water treatment plant for industrial use incorporates water basins such as cisterns, courtyard water basins and retention basins, so that this water automatically becomes part of the production cycle. Our mobile concrete water separation tank, or mo-BAT for short, designed for washing concrete buckets or other washing applications, does its job on construction sites as well as in precast plants.

The mo-BAT from AJF is a system that treats even small quantities of water and residual concrete in a closed water cycle, thereby saving a lot of cleaning water. And filtration? This is simply carried out using a filter bag; no further recycling equipment is required. As soon as sediments accumulate, they are separated and end up in a big bag; the filtered water is drained off via two outlets.

All this saves time and space! Industrial companies such as WMM AG in Illertissen are already using our mo-BAT 1000: wherever precast concrete elements such as ceilings and walls take shape, this efficient mobile water treatment plant makes its contribution in industry – ensuring that every delivery date is met.

Away with traditional settling tanks! There is a more contemporary approach…

Construction site water is full of concentrated mineral particles, and its pH value is equivalent to that of caustic soda. It goes without saying that this type of water does not belong in waterways or sewage systems. This is why construction site inspections check whether you have taken water protection precautions. If not, you could face heavy fines – and the requirements for future projects could be tightened.

Of course, you know that drainage containers or settling tanks are essential for construction site wastewater. However, this is not an ideal solution: sedimentation causes fine particles to settle there; the water is then drained from the settling tank. There is no question of sensible, continuous separation of sediment and water here – this classic strategy is time-consuming, not to mention the space it requires.

Mobile water treatment with mo-BAT – pH neutralisation included

Unlike mobile cement residue water treatment, which not only automates separation precisely, but also takes over what traditionally happens in the neutralisation tank: it is already integrated in the mo-BAT1000+ and mo-BAT3000. The wastewater from the filter big bag is directed specifically towards the neutralisation tank. Chemical neutralisation with CO₂ tackles alkaline wastewater at the pH value. The mobile water treatment plant for industry treats the purified water with carbon dioxide to lower the pH value as intended. Every AJF pH neutralisation plant is tailored to your specific wastewater volumes and requirements.

pH value determination and final pH check, either manually or fully automatically depending on the model, location-independent in a mobile container. To comply with all water regulations, an optional built-in evaluation station reliably checks turbidity and solids content. A fully automated wastewater control system in which all measured values can be called up via the controller display module. And if certain components require maintenance, your system will notify you automatically!

Can concrete producers reuse concrete water for fresh concrete?

Our CWAS cement-water treatment system for the concrete industry is available in both stationary and mobile versions. Concrete water produced during the cleaning of truck mixers still contains many valuable substances. However, these must meet the meticulous specifications of each individual concrete recipe. Water density standardisation allows you to comply with all water specification parameters. You can freely preselect the density values of certain substances in the residual water and integrate grain size processing and binder dosing – and, of course, preset the pH value of the return water. The result is cement water that you can reuse up to a maximum of 100 per cent! Every mobile water treatment plant for industry is a patented system that operates according to the principle of a closed raw material cycle – with a consistently low residual water density. This is essential for complying with the concrete recipe and ensuring reliable concrete strength and consistent quality.

Fully automatic: filtration, sludge dewatering

Not everything in the water can be separated by filters. Mobile water treatment adds flocculant as needed, which binds even the finest particles, neutralises their charge and automatically transforms them into large macroflocs. This prevents them from slipping through the mesh during filtration! An AJF flocculant station offers everything you need for the professional preparation of polyelectrolyte solutions, designed in a modular fashion to meet your requirements. Like a microfilter station with special filters that continuously remove tiny particles of all kinds from the water. Mobile, fully automatic sludge dewatering is also included: it separates solids and residual water from the liquid sludge, leaving behind solid sludge in a form that can be landfilled or incinerated, easily disposed of in big bags. The ideal complement to mobile water treatment wherever wastewater and sludge volumes are particularly high.

AJF at your side – from commissioning to water analysis

Conclusion: A tailor-made, mobile water treatment plant for industry reduces costs – for water, additives and more. Is your plant up and running? AJF Services is also there for you after installation, training and commissioning with advice, repairs and (remote) maintenance, as well as for planned conversions. Maintenance extends the service life of your plant, reduces operating costs and maximises machine availability. Do you have a new plant operator?

We are also happy to instruct him or her in the handling of the mobile water treatment plant. And because every type of water to be treated behaves differently, we also offer filtration or comminution tests and water analyses, so that your treatment leaves nothing to chance.

Problems with waste water disposal and concrete recycling?

Intelligent, mobile water treatment for industry supports you in production and recycling with constant density monitoring, compact, year-round, even in winter operation. Systems that generate less waste and wastewater – and noticeably reduce disposal, personnel and logistics costs, optimise processes and protect the environment. Our prediction: companies in concrete production and processing that focus on high-performance water treatment and sustainability in the future will be the ones that thrive! Want to expand your market position now and design mobile, flexible water treatment for your purposes? Let’s talk!

The article Mobile water treatment plants Industry first appeared on Fresh concrete recycling begins with AJF.

The optimal water treatment plant for companies in the concrete sector?

It treats residual concrete water more efficiently because it is smarter. Efficient means, for example, consuming fewer resources and producing less waste and wastewater that is expensive and time-consuming to dispose of. In compliance with all environmental regulations, residual water is used 100 per cent, meaning it is returned completely to the water and raw material cycle. Water treatment plants for manufacturers who think sustainably want to help their customers secure substantial market shares in the future. And they have recognised that there is no one-size-fits-all solution that is suitable for all concrete manufacturers and concrete processors without distinction.

Concrete recycling or water treatment?

Whether it's fresh concrete recycling, residual water treatment, or process water management, we will find the optimal solution for your plant.

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CWAS cement-water treatment from AJF: Tailor-made, fully automatic

Superior water treatment systems for concrete manufacturers achieve the goal of consistently low residual water density while precisely adhering to all water specification parameters – whether on site at the concrete plant or mobile on the construction site. The magic word is water density standardisation. Water treatment systems for concrete manufacturers can specifically preselect the density of each substance in the residual concrete water as well as the return water pH value.

Thanks to a pH neutralisation system tailored to the company’s specific wastewater volume, wastewater is discharged into the public sewer system safely, with a pH value that complies with legal requirements. Fully automatic pH measurement and final pH checks give manufacturers peace of mind. Grain size processing, binder dosing and evaluation stations for continuous testing of turbidity and solids content can also be accessed via the controller display module.

Effective flocculation and neutralisation of the finest particles efficiently treat water resources. Of course, the dosing station for flocculants is also tailored to individual requirements when it turns tiny flakes into large macroflocs. A modular – individually expandable – microfilter station for industrial requirements works with a needs-based selection of powerful special filters that reliably filter out even the tiniest particles.

Fully automatic water treatment systems for manufacturers such as CWAS also require very few staff: are flocculants running low? Integrated sensors report this immediately. Do components need maintenance? This water treatment system for companies in the concrete industry reports this itself.

Save cement – but still get the right concrete quality

Innovative water treatment systems for manufacturers of concrete components also reduce cement consumption. If the solids content is continuously and accurately determined, more recycled concrete water can be reused at a constant density – saving hundreds of tonnes of cement and CO2. Instead of regularly diluting water due to excessive residual water density, resulting in residual water quantities that then have to be disposed of.

Or, to ensure the quality and strength of components, add more expensive, environmentally critical cement. The solution? Water treatment plants for concrete manufacturers that meet the requirements of EN 1008:2002 for the use of recycled concrete water and work with intelligent density measurement, the values of which are incorporated into production control – with the aim of achieving a specific concrete quality.

As a concrete producer, you select the desired density of all materials in advance. Density too high? Targeted sediment removal or fresh water addition automatically reduces it. Positive side effect: sediments no longer have to be disposed of at great expense, but are reused in concrete production. Everything is integrated into a modular concept – from settling tanks to cisterns.

Whether it’s retrieving wastewater values or probe control, forward-thinking manufacturers of water treatment plants are stepping up to take every step off their partners’ hands, 365 days a year.

Concrete production of the future: automated from start to finish

Automation is the order of the day both nationally and internationally. Not only manufacturers of water treatment plants, but also concepts in the field of dosing systems and storage of aggregates are relying on it. Automatic bucket elevators, for example, enable fast, high-volume loading. Weighing systems are integrated into the bucket conveyors to ensure high precision in the dosing of aggregates – even where the quantities are significantly below the nominal volume of the mixer.

This minimises wear and tear on equipment and simplifies maintenance. Here, too, all processes are organised in a more targeted and controllable manner – from the speed of the mixing stars per mixing container rotation to the exact curve radius of the tipping bucket to its optimised driving and unloading process, controlled by a frequency converter for short transport times. The tipping bucket is connected via WiFi to a mobile chute, which moves into its predetermined position above the formwork to be concreted, precisely according to the production plan.

Central project management – from production planning to mixing recipes

Modern plant control is fully integrated into the existing company network. The aim is to achieve maximum automation in concrete production: production planning is stored in the system, and the production order is sent to the control system of the mixing plant via computer. All the production manager has to do is tick off the product in the order list. All concrete recipes are stored in the database.

Because it has long been established at what constant density the best strength can be achieved. Computer-aided project management makes it possible to supply even large construction projects with concrete elements at short notice. The ingredients required to achieve a specific concrete mix are precisely defined. Modern water treatment plants for concrete manufacturers are the key. Because the quality of the added water determines the setting time, strength development and compressive strength.

Networking, standardising and monitoring production processes in real time

For safety reasons, however, the concreting itself is not fully automatic but semi-automatic. After comparing the configuration with the values of the ordered product and checking whether there are still employees in the danger zone, the system gives the go-ahead for concreting. Finally, the computer calculates the necessary hardening time, etc. Every process is documented – and thus completely traceable, whether it is the production manager involved or the material batch used.

Every single raw material consumption is monitored in real time so that the production plan can be adjusted if reorders are necessary. And every step is standardised, with all reliable parameters known, resulting in a specific outcome: a specific concrete quality! In short, where production processes need to be streamlined, everything is networked and integrated into the digital enterprise system.

Why modern water treatment? Because it solves problems.

As a manufacturer of water treatment plants, we want concrete producers to rethink this issue. What’s in it for you? Continuous production with a complete raw material cycle all year round, integrated as a plug-and-play system in a compact mobile container that takes up minimal space – ready to use.

The control technology is easy to use and can be retrofitted to any machine design if requirements change. The concrete industry, precast plants and ready-mix concrete companies benefit from reliable, energy-efficient systems – from filter cake recycling to mobile concrete slurry separation tanks (mo-BAT) for water purification directly on the construction site.

Overflowing residual water basins, disposal and logistics costs are a thing of the past. Up to 100 per cent of the recovered water is used in concrete production. AJF industrial water treatment plants for manufacturers of fresh concrete ensure that not a single drop of recovered water is lost – it couldn’t be more environmentally friendly!

Break new ground now! Start systematic water treatment

It’s time to rethink familiar approaches and carry out targeted process optimisation. This will enable you to produce not only in a more environmentally conscious manner, but also more economically. Future-proof, tailor-made water treatment plants for manufacturers in the concrete industry quickly pay for themselves. And then? Work with us to expand your market position. Because everything is just right – sustainability, production efficiency and concrete quality!

The article Systematic water treatment: How manufacturers can combine quality and efficiency first appeared on Fresh concrete recycling begins with AJF.

Why use filter presses for concrete sludge?

Concrete grinding sludge, screed and precast production, road construction and more: nothing works without chamber filter presses that filter concrete sludge, separate solids from liquids and separate the sludge into its components. The goal: clean water and a filter cake with a high degree of dewatering. Why all this effort? Concrete slurry and concrete wash water cannot be discharged into the public sewer system as they are. How does it work? A pump sends the concrete sludge under high inlet pressure into the sludge filter press, where solid filter cake gradually deposits in the filter chamber. Once the optimum amount of moisture has been pressed out, the filter cake falls out of the chamber.

Concrete recycling or water treatment?

Whether it's fresh concrete recycling, residual water treatment, or process water management, we will find the optimal solution for your plant.

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How does a sludge filter press work?

The sludge filter press works with filter cloths stretched over parallel, recessed filter plates, which together form the filter chamber and are mounted in a base frame with a hydraulic cylinder. This presses the filter plates together – the number of which varies depending on the plant volume. The pressure sensor signals that the water flow has stopped and the sludge filter press is full. Then the press opens and the filter cake falls out, pressed to a solid consistency and ready for transport. An even lower residual moisture content can be achieved with a membrane filter press: at the end of the feeding process, an integrated membrane presses the filter cake further. However, all this will only run smoothly and economically in the long term if you keep an eye on the condition of your sludge filter press. Particles such as cement residues tend to harden and can clog the filter cloths. You should therefore clean your filter cloths daily to improve efficiency and extend their service life. To do this, you can either remove the filter cloths for washing or treat them with a high-pressure gun and a special active cleaner.

How do backwash and residual water treatment work in practice?

The law stipulates that any concrete waste must be processed in an environmentally friendly manner. In gravel pits, concrete plants and ready-mixed concrete production, filter presses for concrete sludge play a central role in building material recycling, alongside recycling machines and agitators. Depending on the situation on site, customised chamber filter presses may be required, which can convey material from drop heights of several metres. This ensures that there is always sufficient air and space below, and the operator does not have to constantly remove washed-out material! This reduces factory traffic and also lowers energy costs. Let’s get started: Pre-separation of coarse materials > 0.2 mm ensures that only fine particles such as pigments, cement or flour grains < 0.2 mm reach the processing stage. This is an automated process that eliminates the need for manual intervention by the operator. A compressed air diaphragm pump pumps the recycled water – e.g. with an average density of 1.05 to 1.07 kg/l – into the

Chamber filter press. Done! The sludge filter press shakes and ejects the filter cake, ready to be used, for example, as RC material or gravel in road and path construction. Because what applies in the bakery also applies in the concrete industry at the end of the day: this cake is too good to throw away!

What distinguishes a modern filter press for concrete sludge?

When working with a filter press for concrete sludge, there are several basic options: Firstly, stationary, with a manually operated filter press for concrete sludge or as a fully automatic sludge filter press (emptied by a vibrating device); in this case, all units are mounted on a base frame. The most flexible solution? A sludge filter press that is completely assembled in a container with everything you need, so that you can achieve your goal even without a permanent operating building – as a compact system consisting of a sludge filter press, feed pump and sludge depot. A filter press for concrete sludge that automatically checks the fill level and density in the residual water basin – and starts feeding as required. The hut and container are tailored to your requirements as a concrete manufacturer and processor – winter-proof, so that work can continue even at sub-zero temperatures! Of course, comprehensive, innovative concrete recycling plants also include density measurement and pH neutralisation.

Would you like to save water and landfill costs?

An AJF filter press for concrete sludge contains all the components needed to get started right away – and thus performs automated residual water treatment to perfection, whether stationary or mobile. Water density standardisation is part of this – and allows you to precisely define the residual water density in all parameters. A fully automatic treatment plant for cement residual water such as CWAS

– Simplifies handling and transport

– reduces the costs of fresh water, landfill and waste water disposal

– saves personnel costs

– reduces the volume of sludge produced

– quickly pays for itself as an investment

Curious about how you can clean and filter concrete slurry more economically and innovatively? Would you like to learn more about water density standardisation or filter cake processing? Simply get in touch…

The article Sludge filter press: Innovation in residual water treatment first appeared on Fresh concrete recycling begins with AJF.

Water shortage in Germany – Act now!

The Association of Towns and Municipalities warns of water shortages in Germany due to drought – not only private households, but also industry should take action now if possible!

“The drastic increase in water demand in industry, agriculture and also in private households is problematic,” said Managing Director Gerd Landsberg in the Handelsblatt newspaper on 12 July.

“In the wake of heat waves, Germany may also experience regional water shortages. That is why we need even more active water management,” added Mr Landsberg. In addition, the costs of producing groundwater and drinking water will increase enormously in the future.

Concrete recycling or water treatment?

Whether it's fresh concrete recycling, residual water treatment, or process water management, we will find the optimal solution for your plant.

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How can industrial companies save water and thereby reduce not only their environmental impact but also their costs?

How can industrial companies save water and thus not only protect the environment but also reduce their costs?

In the concrete industry, our CWAS cement wastewater treatment plant demonstrates the advantages of a complete raw material cycle! Concrete wastewater can be treated so that it can be reused in a closed circuit for the production of fresh concrete. In addition, we automate your additional water basins, such as cisterns, courtyard water basins or other retention basins, and automatically feed the water they contain into your production cycle.

The AJF Mo-BAT is ideal for treating small quantities of water and residual concrete – a closed water circuit is possible.

WMM AG manufactures high-quality prefabricated elements such as ceilings and walls in Illertissen. In doing so, WMM meets all requirements in terms of construction, quality and guaranteed delivery times.

From the outset, WMM has relied on the mo-BAT 1000, which is a fixed component of water treatment for small quantities of water and residual concrete. Filtration through the filter bag is reliable and efficient. Other costly recycling systems are not necessary. A closed water circuit can be established, saving you a considerable amount of cleaning water.

The article Saving water in industry first appeared on Fresh concrete recycling begins with AJF.

The task of a filter press is to clean suspensions. Solids contained in the liquid are separated from it by means of a filter press. One example of such an application is a filter press for concrete (concrete waste water). Here, the recycled water is cleaned using a filter press and the fine sand and cement (concrete sludge) contained in the water is filtered out. The result is clean, clear water and an easily transportable filter cake.

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How does a filter press work?

In principle, all filter presses work in the same way. Water is pumped through filter cloths and thus filtered out.

The essential components for constructing a filter press are filter plates and filter cloths, as well as a base frame with a hydraulic cylinder that compresses the filter plates.

The filter plate is designed as a half-shell in which the filter cloth is placed. Two compressed half-shells form a filter chamber. The more filter plates are used, the greater the filter volume of the press. The filter plates are guided on the base frame and compressed tightly together by means of hydraulic cylinders.

The contaminated water is pumped into the chambers. The sediments are filtered out by the filter cloths, and the water flows through the cloths, purified, out of the press. As water flows continuously over the chambers and thus over the filter cake that has already formed, the filtration effect is increasingly improved. The filter cake acts as an additional filter element.

The sediments thus form the filter cake in the half-shells. Contrary to what one might assume, the actual pressing of the filter cakes does not take place with the hydraulic cylinder, but with the inlet pressure and the flow rate of the feed pump.

High-quality systems have a pressure sensor at the press inlet for this purpose. Only when a defined back pressure and correspondingly low flow rate are reached is the water supply switched off and the press opened. If the back pressure to be achieved is correctly adjusted, the filter cakes fall out of the press immediately upon opening and are sufficiently dry for removal or further use. At least firm enough to hold their shape.

On our YouTube page, you can find more interesting videos about our water treatment products.

What is the difference between a chamber filter press and a membrane filter press?

Both filter press systems serve the same purpose: the mechanical filtering of sediments from liquids. At first glance, the basic design does not necessarily differ. Both presses have a base frame, filter plates and filter cloths, as well as a hydraulic cylinder for closing and compressing the filter plates. In both the membrane filter press and the chamber filter press, the filter cake forms between the plates, while the clean, filtered water flows over the filter cake and the filter cloths out of the press. In both systems, the dirty water is usually fed in a pressure- and flow-controlled manner.

The big difference lies in the details. In a chamber filter press, the filter plates are designed as rigid half-shells. A membrane filter press, on the other hand, has a membrane integrated into the filter plates, which can be activated after the pressing process and can “repress” the filter cake. This leads to additional dewatering of the filter cake.

To do this, the integrated membrane is filled with either air or a liquid, usually water, and the chamber volume between the filter plates is additionally reduced. In this case, the filter cake is actually pressed through the membrane.

Depending on the configuration of the filter press, both sides or just one side of the chamber can be equipped with a membrane. The ratio of investment costs to the required residual moisture in the filter cake is often used as a decision-making aid here. Membranes on both sides further reduce the residual moisture in the filter cake, but also increase the investment costs.

What are the advantages of a membrane filter press?

In addition to the main advantage already mentioned of additional dehumidification of the filter cake by means of post-pressing via the membrane, the membrane filter press offers further advantages that are helpful in certain applications.

Since the membrane allows the chamber volume to be reduced, it is possible to obtain a dry filter cake even when the chambers are not completely filled, for example due to insufficient dirty water or sediment in the water. In addition, the throughput capacity of the filter press can be increased thanks to the membrane technology.
Can a filter press be automated?

With the right system design and control, filter presses today operate fully automatically. Feeding can be started and stopped, for example, based on the fill level or density in the wastewater tank. It is important to ensure that a filtration cycle is always run through to the end in order to obtain a sufficiently dry filter cake.

However, when dealing with difficult media, such as concrete residual water (recycled water) or cleaning water from screed production, it is very important to pay attention to the condition of the filter cloths.

The remaining components, such as cement in the water, react and harden. This clogs the filter cloths and prevents them from functioning properly. To prevent hardening, we recommend cleaning the filter cloths daily.

The article What is a filter press and how does it work? first appeared on Fresh concrete recycling begins with AJF.

Kutter company: building construction, civil engineering and road construction, own ready-mixed concrete

Kutter has almost 100 years of experience in building construction, civil engineering and road construction, turnkey construction and precast concrete construction, plus asphalt paving and bitumen mixing plants. Its own ready-mixed concrete production ensures independence from suppliers. Kutter also supplies concrete to Austria, which complies with ÖNORM B 4710-1 in strength classes C 8/10 to C 35/45. Today, the founder’s grandsons, the Groll brothers, run the medium-sized company with 2,300 employees and headquarters in Memmingen, together with other managing directors.

Making ends meet? Only through consistent consumption of fresh water

Since the late 1970s, Kutter has also been well established in the field of road construction. Here, too, the motto is: do it yourself, if you can.

Wolfgang Mayer has been with Kutter since 2002 and is responsible for technology and fresh concrete at the concrete plant in Darast, Woringen. “In the past, we simply increased the density,” says Mayer. During the winter months, they just about managed with very consistent fresh water consumption.

Then, in 2020, the order came in for the A96 motorway bridge. “It was clear that we would need a lot of concrete that would need to be heated – and a corresponding amount of fresh water. It didn’t seem feasible to continue as before. Another problem was the reuse of our recycled material.”

Problem: Ensuring watertightness, even during winter operation

To ensure watertightness even during winter operation, the management sought a solution: last winter, the residual water level was very high. So Kutter considered: why not pump the recycled water into a separate container and leave it there for 24 hours? We drained the fresh water back out at the top. This works quite well in principle, unless the concrete slurry is too wet to be disposed of.

“While researching online, we came across the company AJF,” says Wolfgang Mayer. Contact was quickly established: could AJF solve the problem? Mayer highlights the advantages of the winter-proof cement water treatment plant. Problems with excess recycled water only arise when temperatures drop below freezing and normal concrete output is not as high. The requirement: to ensure that the water density is maintained at a value of 1.05 to 1.06 in order to guarantee the desired concrete consistency. “Excessive residual water density causes deposits in the plant, in the water pipes and in the spirit level – and is detrimental to the production of concrete.“

How water treatment works in the container

The AJF water density standardisation process uses intelligent, robust control technology that ensures constant water density in full compliance with DIN EN 1008. The maximum density value is reliably recorded and reduced by targeted removal of sediments or by adding fresh water. The required density values can be freely preselected with the CWAS system.

Instead of spending a lot of money on disposal, thanks to CWAS, a large proportion of the sediments are reused in concrete production via recycled water.

AJF residual water treatment: Individually tailored

The modular system can be expanded as needed. The finished system arrives pre-assembled so that concrete producers can get started right away with plug & play. The clean, compact solution saves water, energy and personnel costs. Wolfgang Mayer from Kutter Transportbeton comments: “AJF arrived on 4 December, set up the container and quickly connected everything. On 8 December, we pressed the first recycled water – everything has run flawlessly since then.”

Waterproofing can be maintained consistently

After the first winter, Kutter no longer has any problems with residual water and concrete slurry. “We can maintain our water density at a value of 1.05 or 1.06 without any problems and have a completely closed circuit,” says Mayer happily. This means that the company is no longer dependent on additional concrete when it comes to recycled water. This problem has been solved. He adds: “I can only recommend the AJF system, which works flawlessly. Anyone who deals with recycled water should really have a water treatment system like this. Whether it’s ready-mixed concrete or a precast plant – it just makes work so much easier!”

The article Kutter Transportbeton saves money and time when handling recycled water and solves watertightness problems first appeared on Fresh concrete recycling begins with AJF.

But whatever the cost, your concrete must meet all specifications – not least in terms of the water-cement ratio. So you add kilos of extra cement per cubic metre. Is this necessary, or can cement be saved even when using residual water?

Why correct dosing helps save cement

Magic? No, a patent-pending system based on the principle of water density standardisation. All you have to do is preselect the exact water density required; smart control technology does the rest. The CWAS system implements a complete raw material cycle, meaning you spend less on the disposal of residual water and sediment waste, on clear water and on additional cement.
Ingredients such as sand and aggregates, as well as water content, correspond to the quantities required by the recipe. Precise dosing reduces costs.

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Whether it's fresh concrete recycling, residual water treatment, or process water management, we will find the optimal solution for your plant.

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Ask yourself: Do I need to use the full two per cent deviation allowed in the total dosage? For a batch of two cubic metres with 3,700 kg of sand and aggregates, this can amount to 74 kg per mix! Saving cement means not compensating for deviations in aggregate dosage and water quantity by adding expensive cement to your concrete mix at a rate of between 5 and 30 kg/m³.

Save cement – with intelligent water treatment and automatic recycling

All this just to be on the safe side when it comes to concrete strength! Don’t leave such process decisions to chance: there is a more accurate, more predictable and more cost-efficient way. Saving cement when using recycled water in concrete? This can only be done effectively if the composition of the solids in the water is determined precisely in every detail – so that production can always be carried out with the correct residual water density. What’s more, the environment will thank you for reducing the amount of cement you use – even modern cement production still releases a lot of CO2. Intelligent water treatment using an automatic recycling system brings measurable savings in precious resources – and the concrete quality is just right!

What are the requirements of DIN EN 1008 for residual water tightness?

Residual water contains aggregates, cement, flushing water from truck mixers and concrete pumps, and possibly rainwater. The concentration of this aqueous fine material suspension varies depending on the origin of the residual water. The grain sizes are less than 0.25 mm. Only residual water with a solids content of less than 1% by weight of the aggregate may be added during concrete production. Only a certain percentage may consist of different aggregates. Solids that are not homogeneously distributed in the residual water must be separated in the settling tank. Details on sampling, testing and assessing the suitability of water can be found in DIN EN 1008. Residual water density, associated mass of solids and residual water volume can be found in the tables there and taken into account in the concrete composition. Further regulations for the reuse of concrete recycling water and for recovered aggregates can be found in the “Guideline for the production of concrete using residual water, residual concrete and residual mortar“, German Committee for Reinforced Concrete (Ri5).

How do you distribute residual water evenly across daily production?

At least once a day, the residual water density in kg/litre must be determined at the time of the expected highest water density – or better still, continuously, around the clock. The average solid density is 2.1 kg/litre, with 1.07 kg/litre being optimal, with a solid mass of 0.134 kg/litre and a residual water volume of 0.936 litres/litre. Incidentally, for high-strength concrete or aerated concrete, you must not use recycled concrete water, only fresh water. But how can the requirement to distribute residual water evenly over daily production be realised in practice? Cement-water treatment plants such as the CWAS from AJF do the job automatically. Stationary but also mobile, the mobile recycled water treatment plant is also suitable for smaller concrete plants. Concrete water is automatically treated – even in winter operation, with a constantly low residual water density of, for example, 1.07 kg/litre.

The article Save cement – make clever use of recycled concrete water first appeared on Fresh concrete recycling begins with AJF.