One of the biggest challenges facing a designer of paper structures is its low resistance to moisture and water. Paper is a hydrophilic material that absorbs moisture from the outside. This causes the hydrogen bonds between the cellulose molecules to loosen and as a result a rapid decrease in strength parameters. In order to be able to use paper as a construction material, there is a need to select and evaluate the effectiveness of the appropriate impregnant, as well as to know its impact on the mechanical properties of the impregnated paper. The paper analyzes the effect of the use of various impregnations, including wood oil, yacht lacquer, and fire-retardant agent impregnation, on the tensile strength of several types of cellulose-derived materials, e.g. corrugated board, solid board, paper cores, and honeycomb board. The effectiveness of the impregnation was also assessed using the method of measuring the contact angle of the reference and impregnated surfaces.

Many paper-related products are in daily use all over the world. Although paper is one of the most recycled materials in the European Union, no end-of-waste criteria have been defi ned. Typical paper and cardboard should be recycled, but paper materials with impurities, such as cooking oil, sand, or plastic, are much more problematic. In particular, paper contaminated with cooking oil or butter (e.g., pizza boxes) is diffi cult waste. Also baking parchment paper cannot be stored as waste paper after use. Composting could be a solution, but in many municipal solid waste collection systems, this waste types are collected with the mixed waste stream, what fi nally leads this material to landfi lling or incinerating processes. Parchment paper and pizza box cardboard contain a lot of cellulose and in landfi lls are a source of CO2 and CH4. Incineration of these materials also leads to CO2 emission. The aim of this study was to investigate the degradation of cooking-oil-contaminated paper in media with a low inorganic nitrogen content. Cardboard usually used for packaging purposes was used as pre-test material. Two types of paper usually used in the kitchen were used: pizza box cardboard and parchment paper highly contaminated with cooking oil. Two types of low inorganic nitrogen media were tested: mature municipal waste compost (MSWC) and leaf mold (LM). The decrease of mass of both paper sample types was correlated with process time. Both tested sample types: dry cellulose materials and paper with cooking oil added, were partly or completely decomposed after 6 weeks of bioprocessing in aerobic conditions without an additional dose of inorganic nitrogen. According to waste separation rules, wet paper or paper contaminated with cooking oil have to be stored with other wastes which are „not possible for further use”. This work show possibility to change these rules.

Sludge from cardboard mill is most commonly landfilled, but it could also be recycled on-site into production or reused in some other way. In this study the use of sludge from cardboard mill as stabilizing agent in the stabilization treatment of cadmium polluted sediment was examined. The effectiveness of treatment and long-term leaching behavior of cadmium was evaluated by determining the cumulative percentage of cadmium leached, diffusion coefficients (De) and by applying different leaching tests (semi-dynamic test, toxicity characteristic leaching procedure, waste extraction test). In order to simulate the “worst case” leaching conditions, the semi-dynamic leaching test was modified using 0.014 M acetic acid (pH = 3.25) and humic acids solution (20 mg l-1 TOC) as leachants instead of deionized water. A diffusion-based model was used to elucidate the controlling leaching mechanisms. Applied treatment was effective in immobilizing cadmium irrespective of high availability in the untreated sample. The controlling leaching mechanism appeared to be diffusion, which indicates that a slow leaching of cadmium could be expected when the cardboard mill sludge as stabilization agent is applied.