Analysis of Hydrothermal Solid Fuel Characteristics Using Waste Wood and Verification of Scalability through a Pilot Plant (vol 10, 2315, 2022)

Abstract

“Seong-Yeun Yoo, In-Kook Kang, Namhyun Kim, Sanggyu Kim, Kangil Choe” were not included as authors in the original publication. The corrected Affiliations and Author Contributions statement appears below. In the published publication, there was an error regarding the affiliations for the addition of authors. In addition to affiliations 2 and 3, the updated affiliations should include: “2 Bioenergy Center, Kinava Co., Ltd., #701-704 7 Heolleung-ro, Seocho-gu, Seoul 06792, Republic of Korea”, “3 Carbon Neutral Division, Korea East-West Power Co., Ltd., #395 Jongga-ro, Jung-gu, Ulsan 44543, Republic of Korea”, “4 Construction Division, Korea East-West Power Co., Ltd., #395 Jongga-ro, Jung-gu, Ulsan 44543, Republic of Korea”. There was an error in the author contributions in the original publication because new authors were added to the original publication. The revised publication added new authors and contributing roles such as re-source, pilot plant design verification, pilot plant experiment analysis and verification, and project manager to the author contributions. All the author contributions were determined according to the added contributing role, and all authors agreed on the re-vised publication. New Author Contributions Statement: Author Contributions: Conceptualization, T.-S.S., K.C. and H.-I.Y.; methodology, T.-S.S., K.C. and H.-I.Y.; validation, T.-S.S.; formal analysis, T.-S.S. and J.-C.L.; investigation, J.-C.L.; Resources, I.-K.K.; data curation, S.-Y.Y. and I.-K.K.; Pilot Plant design verification, H.-B.L.; Pilot Plant test results analysis and verification, N.K. and S.K.; writing—original draft preparation T.-S.S.; writing—review and editing, K.C., J.-C.L. and H.-I.Y.; supervision, H.-I.Y.; Project administration, K.C.; funding acquisition, N.K. and S.K. All authors have read and agreed to the published version of the manuscript. Author Contributions: Conceptualization, T.-S.S., K.C. and H.-I.Y.; methodology, T.-S.S., K.C. and H.-I.Y.; validation, T.-S.S.; formal analysis, T.-S.S. and J.-C.L.; investigation, J.-C.L.; Resources, I.-K.K.; data curation, S.-Y.Y. and I.-K.K.; Pilot Plant design verification, H.-B.L.; Pilot Plant test results analysis and verification, N.K. and S.K.; writing—original draft preparation T.-S.S.; writing—review and editing, K.C., J.-C.L. and H.-I.Y.; supervision, H.-I.Y.; Project administration, K.C.; funding acquisition, N.K. and S.K. All authors have read and agreed to the published version of the manuscript. In the original publication, there was a mistake in Tables 3–8 as published. Table 4 was deleted, titles and contents of some tables were modified, and Figure 4 was added. The corrected tables and figures are as follows and appear below: Comparison of calorific value and mass yield after HTC of waste wood. Comparison of calorific value and mass yield after catalytic HTC of waste wood at the laboratory scales. Laboratory-scale HTC solid fuel analysis according to heavy metal and hazardous substance standards of biosolid fuel. Comparison of calorific value and mass yield after HTC of waste wood at the laboratory and pilot scales. Comparison of calorific value and mass yield after catalytic HTC of waste wood according to catalytic density ratio at the pilot scale. Laboratory- and pilot-scale hydrothermal carbonization solid fuel comparison according to heavy metal and hazardous substance standards of biosolid fuel. Van Krevelen diagram of waste wood and biosolid fuels produced by different HTC processes at the pilot scales. There were errors in the original publication. In consultation with the authors, the inappropriate content was excluded, and the results that could be disclosed were stated. Corrections have been made to these sections: “2.3. Laboratory-Scale Reactor HTC Experimental Conditions and Process, 2.4. Pilot Plant Reactor Configuration and Process, 3.2. Laboratory-Scale Catalytic HTC Effect Analysis, 3.3. Analysis of Heavy Metals and Hazardous Substances on Laboratory-Scale HTC Solid Fuel, 3.4. Pilot-Scale HTC Effect Analysis and Scalability Verification”. CORRECTED Paragraph: 1st paragraph, 3rd sentence: The moisture content of the pulverized raw material was then measured and placed into an aqueous solution inside the reactor to obtain the appropriate moisture content. 1st paragraph, 6–14 sentences: The added catalyst contains inorganic metals and acids. At this time, the case where a catalyst is added to HTC is called catalytic HTC. Additionally, the amount of catalyst added is determined by catalyst conditions. Catalytic conditions according to the experiment were similarly performed according to previous studies [14,15]. The catalyst is a combination of specific inorganic metals and acids. Two combinations designated by the KINAVA Company were used in the above experiment. The first case (Catalyst #1) is a combination of strong acid-based catalysts. The second case (Catalyst #2) is a combination of weak acid-based catalysts. In all cases, they were provided in the form of liquid catalysts prepared by an already specified method. 4th paragraph, 5th sentence: Content is appropriate. 1st paragraoh, 2–4 sentences: When the catalyst concentration ratio was 2-fold, the calorific value and mass yield after HTC were compared. If the calorific value increases after catalytic HTC, it is a combination of Catalyst #1 (a strong acid-based catalyst). The higher the concentration of Catalyst #1, the better the catalytic HTC reaction. 1st paragraph, 6–8 sentences: The catalyst concentration of Catalyst #1 was determined to have a calorific value of ≥25,120 kJ/kg that was a minimum of 1.5-fold more than the catalytic density ratio. When the catalyst concentration was reduced to the initial catalytic density ratio, the calorific value decreased to 25,120 kJ/kg or less, which did not reach the target calorific value. Therefore, in the pilot plant HTC experiment, we decided to add the catalyst at a concentration equal to or greater than 2-fold the catalyst density ratio. 2nd paragraph, 3–5 sentences: Although the catalyst concentration ratios were the same, the strong acid was added in a larger amount than the weak acid, considering the purity of the catalyst. When the strong acid-based catalyst (Catalyst #1) was added, the calorific value was high, but the yield was lower and the amount of catalyst added was increased. When the weak acid-based catalyst (Catalyst #2) was added, the calorific value was lower than when Catalyst #1 was used, but a stable yield was obtained. 1st paragraph, 2nd sentence: Table 5 is the quality standard. 1st paragraph, 9th sentence: It was confirmed that Catalyst #1 had the highest calorific value, but it was not a catalyst combination that could be used in the pilot plant because the chlorine content exceeded the standard for hazardous substances. Therefore, we decided to use Catalyst #2, which satisfied the standard of biosolid fuel as being suitable for the pilot plant-scale experiment. 1st paragraph, 2nd sentence: As shown in Table 6. 2nd paragraph, 1st sentence: listed in Table 7. 2nd paragraph, 2nd sentence: at a catalyst concentration of the same condition. 2nd paragraph, 4–5 sentences: It was increased by the initial density ratio, and the calorific value was measured to be higher than 25,120 kJ/kg at a 3-fold density ratio. It was also confirmed that the mass yield was more than 60% up to a 4-fold density ratio. 3rd paragraph: The chemical positions of the waste wood used as a reactant in these experiments and the biosolid fuels produced from the pilot-scale HTC processes were compared with a Van Krevelen diagram (Figure 4). The atomic H/C and O/C ratios of waste wood were 1.65 and 0.51, which are similar to that of general biomass. After HTC of waste wood at 220 °C for 1.5 h without a catalyst, the atomic H/C ratios of the biosolid fuel decreased from 1.65 to 1.13, and the atomic O/C ratios decreased from 0.51 to 0.39. This reduced the atomic H/C and O/C ratios by 31.5% and 23.5%, respectively, compared to those of the raw material, and showed intermediate levels of peat and lignite. On the other hand, the atomic H/C and O/C ratios of the biosolid fuel produced from the catalytic HTC (Catalyst #2) under the same conditions were reduced to 0.83 and 0.24, respectively. These figures showed reduction rates of 49.7% and 52.9%, respectively, compared to those of the raw material, and showed a degree of carbonization similar to that of general coal. In addition, the atomic H/C and O/C ratios decreased by 26.5% and 38.5%, respectively, compared to the biosolid fuel produced from the HTC without a catalyst. From these results, it was confirmed that Catalyst #2 provided by KINAVA greatly increased the selectivity for dehydration even in the HTC reaction under the same conditions, enabling the production of biosolid fuel with a high calorific value due to a high degree of carbonization. 4th paragraph, 2nd sentence: As shown in Table 8. In the original publication [1], the funder “Korea East-West Power Company of the Republic of Korea (Pilot Plant Development for Green Pellet Production from Woodwaste Using Hydrothermal Polymerization Technology (2019))” was not included. The funding sponsors had a role in the pilot plant design of the study. In the original publication, “S.-Y.Y., I.-K.K. and K.C. are employees of the KINAVA Company. N.K. and S.K. are employees of Republic of Korea East-West Power Company.” was not included. The authors state that the scientific conclusions are unaffected. This correction was approved by the Academic Editor. The original publication has also been updated. © 2023 by the authors.