Development of a technology for utilizing the electroplating wastes by applying a ferritization method to the alkaline­activated materials

• Main Authors: Oleksandr Kovalchuk, Gennadii Kochetov, Dmitry Samchenko, Anton Kolodko
• Format: Article
• Language: English
• Published: PC Technology Center 2019-04-01
• Series: Eastern-European Journal of Enterprise Technologies
• Subjects: industrial waste water; ferritization technology; alkaline cements; ferritic precipitations; leaching of heavy metal ions
• Online Access: http://journals.uran.ua/eejet/article/view/160959

The study reported in this paper reveals the effective way of recycling water treatment products by using them as a component of alkaline cements and concretes based on them. Large-scale utilization of products from waste water purification in the composition of building materials has traditionally been limited given that heavy metal compounds are included in the composition of waste. Materials that are created using such a waste are traditionally considered to be dangerous for human health and the environment. Application of alkaline cements as matrices for binding these wastes and related products makes it possible to solve the task on reliable binding of heavy metals. It was experimentally determined that the main crystalline phases are calcite, quartz, hematite, coesite, and diopside. Also defined is the presence of gelatinous neo formations that are capable of subsequent recrystallization into zeolite-like structures. Such a composition of neo formations provides the involvement of heavy metal ions into the structure of the received material. Compressive strength of alkaline-activated systems that employ water treatment products (industrial wastes of galvanic production) reaches 40 MPa in standard mortars. Application of the developed cements in concretes makes it possible to achieve the strength of 45 MPa without changing the technological process of concrete preparation. The leaching of heavy metals from the matrix of alkaline cements was studied following the aging of up to 28 days by using atomic absorption spectroscopy. The study performed has shown that the alkaline cement matrix is characterized by high immobilizing properties relative to the heavy metal compounds (the level of immobilization of heavy metals ions is up to 99 %) and allows the use of industrial waste water purification products in the composition of alkaline cements and concretes based on them. Application of such an approach will not only solve the environmental problems related to disposing of hazardous products from water treatment, but would also make it possible to obtain building materials for general purposes with high operational properties