Biocrude from hydrothermal liquefaction of indigenous municipal solid waste for green energy generation and contribution towards circular economy: A case study of urban Pakistan.

In this study, biocrude was successfully produced by the hydrothermal liquefaction of municipal solid waste collected from the landfill site of Lahore, the capital of Punjab, Pakistan, boasting a population of 12 million and an annual waste collection of 10 million tons. The hydrothermal liquefaction process was performed at reaction parameters of 350 °C and 165 bars with 15 min of residence time. The solid waste was found to have 78 % dry matter, 22 % moisture contents, 22.2 % ash, 22.69 MJ/kg higher heating value, 52.062 % C, 8.007 % H, 0.764 % N, and 39.164 % O. Non-catalytic process only produced 10.57 % oil, however when using the catalytic process, the biocrude yield improved to 17.61 %, with 22.61 % energy recovery for biocrude and 12.14 % for solids, when using 2 g dose of K ₂ CO ₃ . The resultant biocrude has a 28.61 MJ/kg higher heating value, having 60.28 % C and 9.28 % H. In contrast, the aqueous phase generated had 4.43 pH, 71.5 g/L TOC, and 1.35 g/L Total Nitrogen. TGA indicated that biocrude contains approximately 80 % of volatile fractions of different fuels. The organic compounds having the six highest peak areas in GC-MS were Ethyl ether 25.74 %, 2-pentanone, 4-hydroxy-4-methyl 9.08 %, 2-propanone, 1,1-dimethoxy 5.62 %, Silane, dimethyl (docosyloxy) butoxy 5.08 %, 1-Hexanol, 2-ethyl 4.53 %, and. Phenol 4.07 %. This work makes the first-ever successful use of indigenous solid waste from a landfill dumping site in Lahore to successfully produce useful biocrude with aims of waste reduction and management, circular economy, and energy recovery.
Competing Interests: I have attached the manuscript entitled: Biocrude from Hydrothermal Liquefaction of Indigenous Municipal Solid Waste for Green Energy generation and contribution towards Circular Economy: A Case Study of Urban Pakistan. Imran Naqvi(PhD), Tahir Hussain Seehar(PhD), Muhammad Raashid(PhD), Rab Nawaz(PhD), Zafar Masood(PhD), Sara Mukhtar(MSc), Thamer Abdulhameed Al Johanif(BSc), Anthony Doyle(MSc), Muhammad Nasir Bashir(PhD), Muhammad Mahmood Ali(PhD), M.A. Kalam(PhD), have submitted a research paper for possible publication in Journal of Fuel have no conflict of interest. All the authors who contributed to the work have been mentioned, and they reviewed the manuscript. The work is the author's work and has not been submitted to any journal. Moreover, there is no ethical issue with the manuscript.
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