Scientists of the St. Petersburg State University of Industrial Technologies and Design (SPbGUPTD) have developed a technology for the production of multilayer cardboard with a white top layer made from waste paper. It is necessary for printing information about the product on the packaging. The new technology makes it possible to refuse from importing a foreign analogue and provides a 10-fold saving on electricity and water compared to the production of packaging cardboard using traditional methods.
“We have found a solution to partially replace the wet method of producing a white top layer from recycled paper with a dry one. Calculations after the first commercial production showed that 87 kWh of electricity is consumed per ton of fiber in wet production, and only 9 kWh per ton in dry production. Waste paper production, waste paper are used as raw materials. In fact, this solves three problems at once, such as import substitution, recycling and recycling of paper production waste and saving resources, ”comments the author of the development, Professor of the Higher School of Technology and Energy of St. Petersburg State University of Technology and Energy Nikolai Midukov.
The new method eliminates seven pieces of large-scale industrial equipment from the production cycle and simplifies the very structure of cardboard production. Savings occur not only on electricity, but also on water. At the same time, the quality of the cover layer, which is important for printing, remains at the same high level.
“In the preparation of paper pulp in the wet process, a huge amount of water is consumed: almost 100 liters for the preparation of 4 kg of fiber. This process involves 5-10 pumps that pump the wet paper pulp and drive water between the machines and pools. Dry technology requires a shredder that shreds waste paper, a rotary-vortex mill for defibration and air ducts that drive dry fiber with fans, ”says the developer.
The development of scientists is included in the tasks of St. Petersburg State University of Food and Technology under the strategic project “Development of the production of biodegradable packaging at the enterprises of the pulp and paper industry, the transition from plastic until 2030” under the program of the Russian Ministry of Education and Science “Priority 2030”.
