AAC production has evolved significantly over its 100-year history, with technological advancements playing a crucial role in enhancing efficiency and product quality. Over the past century, numerous technologies have emerged, but not all have endured. In AAC block and panel production, avoiding damages and achieving a low reject rate are paramount for optimal results and superior product quality. Central to this is preventing sticking during production, highlighting the importance of selecting the right technology. 

In 2007, HESS AAC Systems installed a Keen-Crete® - KBT plant at NUH Yapi in Türkiye, which continues to operate in excellent condition over 17 years later. This longevity underscores HESS AAC Systems’ commitment to delivering solutions that stand the test of time. 

NUH Yapi’s plant was the first to incorporate the Tilting/Back Tilting method combination (Keen-Crete® - KBT), significantly reducing but not entirely eliminating sticking during AAC production. 

Initially operating with white separation, NUH Yapi transitioned to the innovative Green Separator based on experiences from other HESS AAC plants. This retrofitting significantly enhanced product quality, eliminating sticking and minimizing the reject rate. 

NUH Yapi utilizes the Lathi mixing concept, complemented by peripheral mixers, as an additional purchase to achieve a homogeneous, fully automated, standard-compliant mixture. A special characteristic is the aeration concept for lime/cement, where built-in pads inflate with air during dosing, facilitating a unique level of dosing accuracy. Hammer strikes on the cone of the storage bins are not visible on the HESS AAC Systems’ mixing tower. 

NUH Yapi’s packaging line is tailored to local requirements and operates fully automatically to streamline processes. 

By diligently implementing HESS AAC’s Keen-Crete® - KBT technology, NUH Yapi achieves minimal reject rates. Remarkably, after 17 years of operation, the factory consistently surpasses production quotas with outstanding quality. 

Despite being 17 years in operation, the plant operates fully automatically, with operators overseeing monitoring and maintenance tasks in a steady, machine-friendly manner. 

Aligned with HESS AAC Systems’ KBT plant versions, NUH Yapi can produce AAC blocks and panels in various raw densities (DIN AAC density classes 300 – 600/>120 – ≤600 kg/m³) meeting requirements, ensuring versatility in construction applications. 

NUH Yapi’s success story exemplifies the enduring impact of innovative AAC production technologies. Through strategic adaption and continuous improvement, the company remains at the forefront of quality and efficiency in the construction materials industry. 

Interview with Nuh Yapi and HESS AAC SYSTEMS 

HESS AAC SYSTEMS, Michael Deissing: "How long have you been working with the HESS AAC SYSTEMS plant?" 

Nuh Yapi, Alp Dogru: "We have been working with HESS AAC SYSTEMS since 2007. "

HESS AAC SYSTEMS: "Why did you choose HESS AAC SYSTEMS? "

Nuh Yapi: "The HESS AAC system is smartly designed to make simple movements with well-equipped automation that makes it easy to operate and guarantees quality. Maintenance durations and costs are lower because of the high-quality machinery manufacturing."

HESS AAC SYSTEMS: "Can you tell us something about your experience with communication and customer service at HESS AAC SYSTEMS?"  

Nuh Yapi: "We are HESS AAC SYSTEMS’s first reference AAC plant with the Green Separator. All HESS AAC customers visited or knew us to witness the performance of the HESS AAC plant with experienced project details. On the maintenance side, we can quickly get the correct response and develop the solution online or on-site supervision."  

HESS AAC SYSTEMS: "What kind of AAC products are produced in your production facility? What sizes of AAC products are produced, and where are they sold?" 

Nuh Yapi: "We can produce AAC blocks according to EN 771 with sizes from 50 mm to 400 mm, with thickness of 600 x 250 mm, and length and height. We produce lintels and panels, too, according to market demand. We can produce AAC-based thermal insulation plate Termoküp™ with a lambda value of 0.045. We sell our AAC block products to European countries, the Middle East, Africa, and even South America. We sell our AAC-based thermal insulation plate Termoküp™ to European countries. We are open to selling our AAC-based thermal insulation plate Termoküp™ with new partners all around the world, especially in EU countries where thermal energy efficiency at buildings is motivated by Green Deal targets."

HESS AAC SYSTEMS: "What is your production reject rate? "

Nuh Yapi: "Our reject product rate is 0.5 %." 

HESS AAC SYSTEMS: "How do you evaluate the quality of the machines supplied by HESS AAC SYSTEMS compared to other suppliers on the market? "

Nuh Yapi: "We have one AAC Plant. We decided to work with HESS AAC Systems in 2006 and still produce with increasing expertise, developing new products, and improving our profit margin." 

HESS AAC SYSTEMS: "How has the Green Separator been running since its installation? What specific advantages have you noticed by using the Green Separator?" 

Nuh Yapi: "The Green Separator is necessary for AAC production; we had a white separator on our old plants where the white product reject rates were around 2%. At this AAC plant, we started with a white separator in 2008, and after some years, HESS AAC SYSTEMS developed the new green separator, which we have used since 2012. We have achieved a 20% production increase, about 80,000 m³/year, with Green Separator, which paid back its cost in a short period."     

HESS AAC SYSTEMS: "How do you evaluate the system’s efficiency after a period of 17 years in operation?" 

Nuh Yapi: "We have been in the AAC business since 1997; we already have an experienced production and maintenance team, which is our value to be in the AAC market with block, lintels, and thermal insulation plate Termoküp™. The HESS AAC plant performed very well in the last 17 years to support our AAC business performance. " 

HESS AAC SYSTEMS: "What role does sustainability play in your production philosophy, and how does using AAC products contribute to this?" 

Nuh Yapi: "We are a part of Nuh Cement Group, Türkiye’s biggest cement plant, where sustainable production is one of our primary targets. We have waste heat recovery and hydropower plants for renewable energy production. Besides those, we have ongoing investment projects for Wind Power Plants and Solar Power Plants to be in operation. Our AAC Plant has had an exhaust steam accumulation system in operation for ten years. We have a project planning biomass combustion at our circulating fluidized bed steam boiler.  We have a Research and Development Center focused on AAC and the sustainable production capability of various raw materials. Nuh Yapi is a lime producer, too. We developed and produced aluminum paste for the AAC process at our plant. In our AAC products, the cement, lime and aluminum paste are produced by our own company. I think we are the only AAC producer in the world with these three central raw material production capabilities. As the producer of cement, lime, and aluminum paste, we are working on lowering the carbon footprint of these raw materials to produce the most sustainable AAC products in the world." 

HESS AAC SYSTEMS: "How has the cooperation with HESS AAC SYSTEMS developed over the years? " 

Nuh Yapi: "As I mentioned, we are the first plant of HESS AAC, so we developed the system altogether. NUH YAPI and HESS AAC cooperated perfectly. If there is a better solution, it is applied in Nuh Yapi, or any process development requested/done by Nuh Yapı is saved as a modernization of HESS AAC Systems."  

HESS AAC SYSTEMS: "Can you tell us about your long-term strategy regarding using AAC technologies in your company?" 

Nuh Yapi: "We have one AAC plant now; we are now more focused on value-added AAC products like Thermal insulation plate Termoküp™, lintels, and panels than standard blocks. We have a patent application on Termoküp™, and we are studying more projects to develop Termoküp™ and lambda 0.06 – 0.07 blocks." 

HESS AAC SYSTEMS: "How do you anticipate the future of the AAC market? Are there any market or industry trends that could influence the development of the AAC market in the coming years? "

Nuh Yapi: "The AAC market will be a leading wall material with the help of the net zero road map of the European Autoclaved Aerated Concrete Association. AAC is always preferred because of its natural raw materials and fireproof structure. And no wall product recovers CO2 back on its life cycle better than AAC."  

HESS AAC SYSTEMS: "Thank you for the fantastic interview, and we look forward to continuing our excellent cooperation." 

The interview was conducted by Alp Dogru, Investment and R&D Center Manager at NUH Yapi, and Michael Deissing, Sales Manager at HESS AAC SYSTEMS.