04211nas a2200409 a 450000500170000000800410001703500150005809900270007310000180010024501300011826000670024830000430031549000270035850001500038550200590053552021960059465000120279065000180280270000330282070000490285370000410290271000500294381000590299385600650305290700250311790200110314299800280315394500100318194500100319194200070320194200070320890901580321590901710337399900150354495201130355995201290367220260817162832.0260616s20269999th u  ms t    000   eng d  a.b12508366 9aAIT Thesis no.EV-26-241 aKhan, Tasbiha10aApplication of anaerobic digestate-derived biochar in the semi-continuous anaerobic digestion of sewage sludge and food waste  aPathum Thani, Thailand :bAsian Institute of Technology,c2026  a112 leaves :bill.+e1 online resource1 aThesis ;vno. EV-26-24  aA thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Environmental Engineering and Management  aThesis (M. Eng.) - Asian Institute of Technology, 2026  aDigestate-derived biochar was used to examine the effectiveness of semi-continuous anaerobic  co-digestion of food waste and sewage sludge under mesophilic conditions. Even though  anaerobic digestion is a common method for producing biogas, instability brought on by acid  buildup, ammonia inhibition, and varying organic loading rates (OLR) frequently limits its  effectiveness. In order to overcome these obstacles, biochar made from anaerobic digestate was  used to improve methane production and system stability.  At 35 ± 1°C, two identical lab-scal Continuous Stirred Tank Reactors with working volumes of  6 and 8 L were used. Reactor R1 received biochar (0.8, 1, 2, and 5 g/L), and reactor R2 was  used as a control. To evaluate performance under both stable and stressful situations, reactors  were run with increasing OLR. TS, VS, pH, alkalinity, ammonia nitrogen, VFAs, biogas  generation, and methane concentration were among the important variables that were tracked.  SPSS was used for statistical analysis.  Reactor stability and performance were greatly enhanced by the addition of biochar; R1  maintained a more constant pH (6.98{u2013}7.81) than R2 (6.71{u2013}7.35) and demonstrated less  ammonia accumulation (95.19{u2013}203.03 vs. 129.28{u2013}319.46 mg NH₄-N/L). Lower FOS/TAC  ratios (0.27{u2013}0.36) and lower VFA levels (476{u2013}792 mg/L) in R1 compared to R2 (up to 0.55  and 1148 mg/L) demonstrate improved process stability. Additionally, R1 produced more  biogas, with methane content reaching around 53% compared to about 42% in R2, especially  at ideal biochar dosages of 1-2 g/L. Better reactor performance was also demonstrated by  improved substrate degradation (TS up to 3.92). Biochar's high surface area and porous  structure, which encourage microbial activity and DIET, are responsible for these  improvements; 500°C biochar exhibits the best overall performance.  Overall, digestate-derived biochar is an effective additive for improving anaerobic co-digestion  stability and methane production. Future research should focus on optimizing biochar dosage,  long-term performance, and microbial mechanisms under varying operating conditions.   0aBiochar 0aSewage sludge0 aGhimire, Anish,eChairperson1 aCruz, Simon Guerrero,eExamination Committee1 aXue, Wenchao,eExamination Committee2 aPMU-KPCIP-AIT Scholarship,eScholarship Donor2 aAsian Institute of Technology.tThesis ;vno. EV-26-24403Full-Textuhttp://203.159.5.9/ait-thesis/detail.php?q=B24468  a.b12508366bmnarcca  a260622  b0c260619dmeh  fag0  lmnarc  lmnarc  c67  c40  aBarcode : -bCREATED : 2026-06-16cRECORD # : i13605616dLPATRON : 0eLCHKIN : -f# RENEWALS : 0g# OVERDUE : 0hIUSE3 : 0iTOT CHKOUT : 0jTOT RENEW : 0  aBarcode : 30050120420863bCREATED : 2026-06-17cRECORD # : i13606050dLPATRON : 0eLCHKIN : -f# RENEWALS : 0g# OVERDUE : 0hIUSE3 : 0iTOT CHKOUT : 0jTOT RENEW : 0  c6469d6469  00104070aMAINbMAINcmnarcd2026-08-17l0oAIT Thesis no.EV-26-24r2026-08-17 16:28:33t1w2026-08-17y67  00104070aMAINbMAINcmnarcd2026-08-17l0oAIT Thesis no.EV-26-24p30050120420863r2026-08-17 16:28:33t1w2026-08-17y40