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Sewage sludge is a semi-solid waste material created as a result of the sewage treatment of industrial or municipal wastewater. Because the laws and regulations of the European Union require not only a reduction in waste generation but also the preparation of waste for reuse and disposal, it is necessary to look for new methods of the application of sewage sludge as part of sustainable waste management. In this study, ash formed as a result of the combustion of sewage sludge from the sewage treatment plant in Płaszów, Krakow in a fluidised bed furnace at a temperature of around 800°C was used. Sewage sludge ash (SSA) contains over 30% SiO2 and approx. 10% Al2O3, which indicates potential applications in geopolymer materials. In this study, samples of geopolymer mortars with a binder containing sewage sludge ash as well as fly ash (FA) and ground granulated blast furnace slag (GGBFS) were prepared. The mechanical parameters were determined after 2, 7, 14, and 28 days. The results show that the sewage sludge ash-based geopolymer shows binding properties at ambient temperature and, depending on the presence of FA and/or GGBFS, the compressive strength varies from 5 to 45 MPa after 28 days. The aim of the research was also to determine the total content of heavy metals (Sb, As, Cr, Cd, Cu, Ni, Pb, Hg, Zn) in the raw materials used and their leachability from the structure of the hardened materials. Immobilisation of heavy metals is very promising. Based on the results of tests, it seems possible to use SSA in geopolymer materials, but not as the main component of the binder.

Geopolymers may be considered as an alternative materials to Portland cement ones, providing an opportunity to exploit industrial wastes or co-products with promising short and long-term performances in the construction field, f.ex. for reparation issues. However, these materials are porous and consequently their durability depends on the risk of intrusion of aggressive agents. In order to assess their durability, we propose to investigate in this study gas permeability of sound and mechanically loaded specimens. Loading is performed using a splitting tensile test driven by a crack opening displacement up to a level of 50 microns. Tests are performed on four types of blended fly-ash (FA) and ground granulated blast furnace slag (GGBFS) geopolymer mortars, containing four different levels of GGGBF slag in the binder: 0%, 10%, 30% and 50% wt. Results show a positive effect of blending with slag in terms of modulus of elasticity and tensile and compressive strength, as well as the permeability. However, permeability recovery after cracking is the lowest when blending is the highest.

The advent of modern aluminosilicate binders has resulted in practical uses for fly ash, which belongs to the group of secondary mineral raw materials; this provides an interesting alternative to cementitious binders, which have a large carbon footprint. Geopolymers mineral binders with a growing range of applications in construction. Their inorganic, amorphous structure endows them with better resistance to high temperature compared to cementitious binders. In this study, the alkaline activation of aluminosilicate Połaniec Fly Ash made it possible to obtain noncementitious material with compressive strength of 18.5 MPa. The article presents the results of a comparison of characteristics of geopolymer mortar and Portland cement mortar after thermal exposure.

Despite the many advantages, each type of transport, there are many people for the health and life of people. This means that some of the challenges that are not productive have higher energy levels. Substitution of the instrument's characteristics. Management of the fleet of tourist company arders enabling the company to improve and client's operational affairs on the elements of reliability, service compliance, readiness and security (RAMS). The RAMS method used in railway transport has found application in monitoring the maintenance of railway vehicles in maintenance management system and the IRIS Standard. In the article, the authors present the method of assessing the technical maintenance of road vehicles based on the elements used in the RAMS analysis.