fly ash

DECARBONISATION OF INDUSTRIAL GAS EMISSIONS BY ADSORPTION METHODS

The article is dedicated to the problem of decarbonising industrial gas emissions using adsorption methods. The article examines promising approaches to reducing carbon dioxide (CO₂) emissions using adsorption materials with high selectivity and efficiency in capture processes. The purpose of the study is to determine the adsorption capacity of various types of adsorbents, including synthetic and natural materials, in particular, fly ash synthesised by the hydrothermal method, zeolite obtained by the sintering method, natural zeolite, and fly ash from thermal power plants.

OPPORTUNITIES OF WET-HANDLED COAL BOTTOM ASH USE IN BINDING MATERIALS: А REVIEW

Nowadays conventional binding material for the construction sector is Portland cement. Portland cement consists mainly of high-energy intensive with a significant carbon footprint Portland cement clinker. Reduction of clinker content in binding materials becomes the utmost priority for scientists in the field, it is reflected in manufacturers’ Sustainability Road Maps.

Development of Lightweight Grouting Materials Based on By-Products of Ukrainian Industry

A new competitive class of grouting materials has been created. These lightweight grouting materials (LGM) with a density of 1370–1650 kg/m3 consist of oil-well Portland cement PCTI-100, fine powder of PE grade (a by-product of fireclay production from kaolin), acidic fly ash from state district power plants, and lime dust (a by-product of lime production). The composition of the products formed during LGM hydration was clarified by X-ray phase and differential thermal analysis.

PREREQUISITES FOR THE IMPLEMENTATION OF THE EUROPEAN EXPERIENCE IN THE USE OF ASH-SLAG MATERIALS IN THE CONSTRUCTION OF HIGHWAYS: А REVIEW

The European Green Deal is the latest climate and environmental protection program launched by the EU. This is a strategy to transform the EU into a resource-efficient economy, in which in 2050 there will be zero greenhouse gas emissions and economic growth will be decoupled from the use of natural resources. After approving the National Economic Strategy for the period until 2030, Ukraine joins and focuses on the European Green Deal and aims to achieve climate neutrality in 2060 (Natsionalna ekonomichna stratehiia, 2021).

BEHAVIOR OF SUPERPLASTICIZED CEMENTITIOUS SYSTEMS FOR SELF-COMPACTING CONCRETE

The article presents the peculiarities of obtaining superplasticized cementitious systems "Portland cement – fly ash - superplasticizer" to find a rational provision of the given construction and technical properties of concrete. It was studied the physico-chemical peculiarities of the hydration processes of superplasticized cementitious systems. There were solved problems of directional formation of the microstructure of cement stone.

Physico-Chemical Peculiarities of Weighted Thermostable Plugging Materials Hydration

A new competitive class of plugging compositions (weighted non-shrink plugging materials) has been created using as components a fly ash from thermal power station, a weighting additive and a superplasticizer. X-ray phase analysis identified the composition of new materials formed in the hydration process of the developed plugging compositions. The kinetic curves of the plugging material expansion in a wide temperature range have been obtained.

DESIGNING OF ALKALINE ACTIVATED CEMENTING MATRIX OF ENGINEERED CEMENTITIOUS COMPOSITES

The development of high-performance materials, which are characterized by high compressive and flexural strength, durability and performance properties, is an urgent problem of modern construction. Engineered cementitious composites are one such material. Improving of properties of composites is achieved by partial replacement of cement with supplementary cementitious materials. The ratio of binder and filler components and superplasticizer consumption were selected.

MODIFICATION OF CEMENTITIOUS MATRIX OF RAPID-HARDENING HIGH-PERFORMANCE CONCRETES

The paper presents the results of research concerning the peculiarities of modern High Performance Concretes based on cementitious systems "Portland cement – active mineral additives – micro fillers – superplasticizers – accelerators of hardening". Physico-chemical regularities of structure formation of super plasticized cementitious systems are established.

Development of Heterogeneous Alkali Methoxide Catalyst from Fly Ash and Limestone

This study is aimed to use fly ash and limestone as raw materials for preparing alkali methoxide heterogeneous catalysts for transesterification of palm oil into biodiesel. The heterogeneous catalyst was synthesized from fly ash and limestone through wet and dry methods and calcined within 1073–1273 K. X-ray diffraction and scanning electron microscopy analyses indicated the well-dispersed presence of the Ca(OCH3)2 crystal over the fly ash and limestone framework, which was mixed using wet method and calcined at 1073 K (W-800).

SELF-СOMPACTING СONCRETES, HARDENING AT DIFFERENT TEMPERATURE CONDITIONS

In the article the features of reinforced concrete hardening at different temperature conditions and the current issues of preparation technology of Self-Сompacting Сoncretes (SCC) on the basis of superplasticized cementitious systems, combining knowledge of structure and modifying Portland cement compositions "Portland cement – active mineral additives – microfiller – superplasticizer – accelerator of hardening" to search for rational making provision of technical and building properties of concrete in the changing factors of its composition, technology and exploitation are shown.