"The pulp and paper industry is one of the most polluting branches of the national economy. During the production of cellulose, lignosulfonates are formed, the demand for which is now less than their quantity. Unprocessed waste decomposes for a long time and can disrupt the oxygen balance in reservoirs, which leads to the destruction of microorganisms and can negatively affect food chains. Therefore, we have proposed a waste-free and environmentally friendly industrial technology that will allow us to improve building materials", says Alyona Zhulanova, a graduate student of the Department of Environmental Protection at Perm Polytech University.
Due to the unique properties of lignosulfonates, they are used in construction, in the production of pigments, dyes and emulsion stabilizers. The binding properties of waste are used in the foundry industry, as well as in the production of feed, trace elements, fertilizers and pesticides in agriculture. In the oil and mining industries, they are used as surfactants.
To determine the most optimal composition of cement, the researchers compared several samples of a mixture with different content of cellulose waste. The scientists received the material for the study at one of the pulp and paper enterprises of Perm.
Environmentalists found out that with an increase in the content of waste in the mixture, the cement hardening time increased. The optimal amount of lignosulfonates in the cement mixture was 25%, and the most effective composition was the ratio of 100kg of alumina cement, 150kg of sand and 20kg of lignosulfonates. The waste allowed increasing the strength and thermal insulation properties of cement. According to the scientists, with the help of the technology, it is possible to dispose of waste and obtain composite building materials.