Hydrothermal carbonization for sludge disposal in Germany: A comparative assessment for industrial‐scale scenarios in 2030

Abstract

The efficient use of biogenic residues can make a significant contribution to increase resource efficiency. Due to its high energy efficiency, hydrothermal carbonization (HTC) is being discussed as a potentially suitable technology for particularly wet and sludgy biogenic residues. In Germany, however, it has not yet been established at industrial continuous operation. Among others, this is due to missing solutions for the economic treatment of the high organic loads in the liquid by‐product and insufficient knowledge on long‐term processing. Nevertheless, it is still expected that HTC could be able to contribute in the future, especially for sewage sludge disposal. Whether and under what conditions this could be the case is the subject of this study. The competitiveness of modeled cases for industrial sewage sludge HTC, which address different future paths, compared to thermal sludge treatment is investigated by using a multi‐criteria instrument. Results show that HTC can only compete with the reference technology if certain framework conditions are given. Particularly, an efficient phosphorus recycling should be integrated and the production costs of the solid product should be at least less than €325 per metric ton according to this case study. The treatment performance of the liquid phase should be as high as possible whereby costs for further treatment equipment should be minimized, so that mentioned productions costs are not exceeded. This article met the requirements for a gold‐gold JIE data openness badge described at http://jie.click/badges.

Phosphorus recovery from hydrothermal carbonization of organic waste: a review

“…The common trend in industrial applications of HTC includes the addition of acids (such as H 2 SO 4 ) to recover P from the liquid product. Even though high recovery rates can be achieved through this scenario (>85%), the costs of acid addition, maintenance, and the clean‐in‐process can reach up to 15% of additional costs from the total sum 120 . For this reason, several economic studies involving P‐recovery from HTC at industrial scales reported results that are less competitive with the traditional methods.…”

“…Even though high recovery rates can be achieved through this scenario (>85%), the costs of acid addition, maintenance, and the clean-in-process can reach up to 15% of additional costs from the total sum. 120 For this reason, several economic studies involving P-recovery from HTC at industrial scales reported results that are less competitive with the traditional methods. For instance, González-Arias et al (2021) showed that the price of hydrochar produced at industrial scale can range from €390/ton to €590/ton depending on the plant size.…”

Lithium‐ion battery cell production in Europe: Scenarios for reducing energy consumption and greenhouse gas emissions until 2030

“…Because battery cell production is still relatively in its early technological stages, there is much potential to improve efficiency, energy consumption, and corresponding GHG emissions in battery cell production. The study is structured analogously to Reißmann et al (2021). Analogously, four different scenarios that may have a significant impact on improving the energy consumption and corresponding GHG emissions of battery cell production were analyzed (Figure 2):…”

“…The study is structured analogously to Reißmann et al. (2021). Analogously, four different scenarios that may have a significant impact on improving the energy consumption and corresponding GHG emissions of battery cell production were analyzed (Figure 2): Market‐driven (MD) scenario : In this scenario, the strong growth of the battery cell market, which is expected to reach up to 600% of the current level by 2030 was taken into account (Hettesheimer et al., 2021; Zhou et al., 2021).…”

Process Waters from Hydrothermal Carbonization of Waste Biomasses like Sewage Sludge: Challenges, Legal Aspects, and Opportunities in EU and Germany

“…The quantities/yields depend on the process parameters as well as on the input material itself [25,26]. A well-functioning, reliable, and economical disposal, respectively, and treatment of the PW is essential for the successful commercialization of the HTC technology [27].…”