Effect of temperature and organic loading rate on upflow anaerobic sludge blanket reactor and CH₄ production by treating liquidized food waste

Abstract

Anaerobic treatment of liquidized food waste (LFW) was carried out in an upflow anaerobic sludge blanket reactor (UASBR) by stepwise increase in organic loading rate (OLR) and temperature. The chemical oxygen demand (COD), total organic carbon (TOC), biogas and methane production were measured at hydraulic retention time (HRT) of 10 to 4d, and start up strategy of the reactor was monitored for 10 weeks. Thermophilic condition was achieved by increasing the temperature from 30 to 558C, and pH was maintained at 7 6 0.5 throughout the experiment. Maximum COD removal efficiency was 93.67% (r 5 0.84) at an OLR of 12.5 g-COD/LÁd and 4d HRT. Maximum TOC removal efficiency was 79.14% (r 5 20.94) at an influent TOC concentration of 3.59 g/L. Biogas and methane yield were recorded to a maximum of 1.364 L/g-COD removed Ád (r 5 0.81), 0.912 L/g-COD removed Ád (r 5 0.83), and average methane content of biogas was 63%. The reactor was fully acclimatized at 558C and achieved stability with high removal efficiency and biogas production. An OLR of 12.5 g-COD/LÁd and HRT of 4 days were suitable for the treatment of LFW in UASBR. The treatment process can also be extendable for more than 10 weeks without any measurable problem.

Effect of Cod Loading Rate on an Upflow Anaerobic Sludge Blanket Reactor During Anaerobic Digestion of Palm Oil Mill Effluent With Butyrate / Suvartojamo CHDS Poveikis Palmių Aliejaus Gamybinių Nuotekų Su Butiratu Anaerobinio Pūdymo Plokšteliniame Reaktoriuje Metu

“…This causes a drop in pH, which inhibits methanogenesis (Parawira et al 2006). It was found that digester could tolerate the concentration of acetic acid up to 4000 mgl -1 without inhibiting gas production (Latif et al 2011a). In this study the acetic acid concentration was found up to 1193 mgl -1 which was suitable for digester.…”

“…However, the gas production will increase with COD loading rate till a stage where methanogens could not work quick enough to convert acetic acid to methane (Latif et al 2011a). Methane production increased linearly with the COD loading rate up to 1.77 to 4.80 CODl -1 d -1 .…”

“…Among the high rate anaerobic reactor for the industrial effluent treatment, the use of an upflow anaerobic sludge blanket (UASB) process has gained popularity in recent years, with over 500 installations worldwide (Latif et al 2011a). This is due mainly to the positive energy balance of anaerobic treatment processes and the development of an inexpensive and high rate treatment systems (Misevicius, Baltrenas 2011).…”

Immobilized cement kiln dust enhances biomass and neutralizing of palm oil mill effluent for biogas production

“…So, it can be concluded that initially the addition of CKD may cause some inhibition in biogas production. It gets stable because of increase in buffer capacity of the substrate [27][28][29]. Therefore, the time consumed for the conversion of calcium acetate into methane and carbon dioxide is comparatively higher than that of a normal one [30].…”

Palm Oil Mill Effluent Treatment Process Evaluation and Fate of Priority Components in an Open and Closed Digestion System

“…Because of this, the biogas production rate in both tanks was almost low, but it was continued because of the low concentration of VFA in the organic matter 31 found low biogas yield and organic matter removal because of the accumulation of inhibiting substances, such as volatile fatty acids 32 reported that COD removal was greater than VFA removal at the same pH and initial concentrations 20 . Furthermore, VFA removal efficiency is affected not only by VFA species and concentration but also by other conditions, such as operating parameters and physical, chemical, and biological factors 33 . For example, it is known that VFA removal by activated sludge is dependent on dissolved organic matter 34 and pH 35,36 , whereby …”