The amount of returned concrete in industrialized countries varies from 2 to 3% of the overall concrete production; this means that, every year, from 500 to 700 million tons of concrete are not used and come back to the ready-mix concrete plants with the truck mixers; in most cases, it becomes a waste, representing a serious environmental problem at the plant.
FROM REFUSAL TO A NEW LIFE: AN ADMIXTURE CAN TRANSFORM RETURNED CONCRETE DIRECTLY FROM MIXER TRUCKS
In 2012 Mapei developed RE-CON ZERØ, followed by the next generation product RE-CON ZERØ EVO, a bi-component powder additive to recover returned concrete. By adding RE-CON ZERØ EVO to the truck mixer, it is possible to transform, in few minutes of mixing and without any waste production, returned concrete into aggregates, which can be totally recovered and recycled to produce new concrete.
RE-CON ZERØ EVO is the most sustainable system to recover returned concrete, because landfilling is completely avoided and, with the “in-house” production of 2.3 tons of aggregates from 1 m3 of returned concrete, quarrying is reduced and natural resources are preserved. The economic saving arises from the total cut of the disposal costs and the reduction in the supply of virgin aggregates.
NR-MIX, SUSTAINABILITY PARTNER IN JAPAN
Japan is one of the countries where Re-Con Zerø EVO is most successful, thanks to the commitment of NR-MIX (Nagaoka Ready-Mixed Company), Mapei exclusive distributor of RE-CON ZERØ EVO for Japan. NR-MIX is a family company, established in 1967, and 2017 is the 50th anniversary of its foundation. The current CEO, Mitsuya Miyamoto, 39 years old with a Master Degree in Political Economy at Meiji University of Tokyo, strongly believes in innovation and circular economy. For these reasons, he considers RE-CON ZerØ EVO as the keystone to improve the sustainability of concrete in Japan.
With his technical team, he developed an innovative concrete, ECON®, based on 100% aggregates produced from returned concrete admixed with RE-CON ZERØ EVO. This new concrete is now produced at the new batching plant in Nagaoka, in the Shizuoka Prefecture, in Central Japan. Thanks to the excellent performance and durability and the low environmental impact, ECON® is now widely used as non-structural concrete for slabs, foundations and parking lots all over Japan.
Mitsuya Miyamoto is also the President of GNN, an association of more than 100 Japanese ready-mix concrete companies, many of them using RE-CON ZERØ EVO to recover returned concrete. He is also very active in introducing, through GNN, innovative technologies and materials in the Japanese concrete industry, assisted by his International Business Manager Alberto Ferrari.
TESTING GOES ON
Mapei and NR-MIX, in cooperation with Shiraishi Kensetsu Ready-Mix Company, based in Okayama Prefecture, in 2015 developed RE-CON ZERØ SPRAY, a special liquid additive which is sprayed inside the drum of the mixer and eliminates the need of washing the truck mixers after the delivery of concrete. RE-CON ZERØ SPRAY allows to save large volume of washing water and contributes to reduce wastewater and pollution in the ready-mix concrete plants.
Recently, Mapei and NR-MIX, in cooperation with the Japanese Concrete Pumping Association and Kawabata Kogyo, a Japanese manufactuter of pump machines, have developed RE-CON ZERØ PUMP, an unique product which allows to recover residual concrete from the tanks of the concrete pumping trucks. The first full container of Re-Con ZerØ PUMP will be shipped soon to Japan from the Mapei plant in Robbiano di Mediglia (Northern Italy).
Japan is one of the most advanced industrial countries, leaning forward with innovative spirit for creating new sustainable products and developing new sustainable technologies. Mapei and NR-MIX play an important role in this process, contributing with the Re-Con ZerØ product line to make the Japanese concrete industry more and more sustainable.
Giorgio Ferrari. Research & Development Laboratories, Mapei SpA