1/2021
Low-temperature treatment of waste PET
Today, waste plastics represent a promising source both for energy production and chemicals. One way to use their potential is pyrolysis under well-defined conditions. This work presents a suitable method for treat-ment of waste polyethylene terephthalate (PET) using low-temperature pyrolysis realized by heating rates of 5 °C.min-1 (slow pyrolysis) or 25 °C.min-1 (fast pyrolysis) up to final temperature of 400 °C. Under these con-ditions, the valuable products were formed, namely solid fuel with HHV 31-33 MJ.kg-1 and liquid mixture containing mainly ethylene glycol and aldehydes. While slow pyrolysis provides mainly solid fuel, ethylene glycol and aldehydes, main products of fast pyrolysis are solid fuel and paraldehyde.
Remediation of scrap iron contaminated by odorants
Characterization of possible alternative materials for the production of marine fuels
Maritime transport is a significant contributor to the environmental pollution. For this reason, the maximum sulfur content in liquid marine fuels has been drastically reduced since January 1st 2020 for deep sea areas. This reduction can be solved by diluting the conventional high sulfur fuels with suitable low sulfur components. However, mixing two or more components with each other carries a potential risk of incompatibility or instability of the final product, especially in the case of longer storage and subsequent transportation to the end consumers. For the above reasons, this work deals with the mapping of alternative raw materials that could be used to produce very low sulfur fuel oils (VLSFO) with a sulfur level up to 0.5 wt%. A total of 5 raw materials (1 conventional fuel oil – HSFO and 4 alternative raw materials) were characterized. The individual raw materials were compared to each other with regard to the quality properties required for marine fuels according to the ISO 8217. Subsequently, the suitability of these raw materials for further mixing was outlined in order to meet the required quality parameters for marine fuel mixing.
Methods of landfill gas treatment in landfills in integrated prevention system
The article focuses on the issue of landfill gas management in landfills, which are within the scope of Act No. 76/2002 Coll., on integrated prevention. Although landfilling as a way of disposing of municipal waste is in decline, the subsequent care of landfills will continue for another decade after their closure, and landfill gas must be captured even then. The article summarizes information on the method of landfill gas management obtained through the information system of integrated prevention as well as the rules for landfill gas management according to the valid Czech technical standards. According to data obtained from the public database of the integrated prevention system, 136 relevant landfills were identified. The application of a cogeneration has the largest share in the way of landfill gas management. If a cogeneration unit is installed at the landfill, it is in most cases operated by a company other than the landfill operator. It was also found that the region with the lowest population density has the largest number of landfills with low capacity. Due to the fact that the production of landfill gas decreases over time, it is possible that there will be changes in the way landfill gas is handled at individual landfills.