Co-digestion Of Food Waste Research Articles

Effect of co-digestion of tylosin fermentation dreg and food waste on anaerobic digestion performance

In this study, the effects of adding different food waste proportions (volatile solids ratio of 3:7, 5:5, 7:3) to tylosin fermentation dreg on anaerobic digestion were investigated. The results showed that the co-digestion group (294–399 mL·g-VS−1) increased methane production by 14.8%–55.5% compared with tylosin fermentation dreg alone-digestion (256 mL·g-VS−1). The correlation analysis showed that pH, total volatile fatty acids and acetic acid were the most important factors affecting cumulative methane production. Tylosin in the solid and liquid phases decreased significantly after anaerobic digestion, indicating that tylosin could be effectively removed by co-digestion, and the total removal rate was 68.2%–83.7%. Therefore, due to the satisfactory methane yield and the tolerable tylosin removal rate, it is feasible to make the co-digestion of tylosin fermentation dreg and food waste.

A new approach to enhance the conventional two-phase anaerobic co-digestion of food waste and sewage sludge.

Two-phase anaerobic co-digestion (TAcoD) is a versatile technology for the simultaneous treatment of organic materials and biogas production. However, the produced digestate and supernatant of the system contain heavy metals and organic substances that need to be treated prior to discharge or land application. Therefore, in this study, an innovative TAcoD for organic fertilizer and high supernatant quality achievement was proposed. In the conventional TAcoD, mixed sewage sludge (SS) and food waste (FW) were first hydrolyzed in the acidogenic reactor, and then the hydrolyzate substrate was subjected to the methanogenic reactor (TAcoD 1). In the modified TAcoD (TAcoD 2), only FW was fed into the acidogenic reactor, and the produced hydrolyzed solid was directly converted to the organic fertilizer, while the supernatant with high soluble chemical demand (SCOD) concentration was further co-digested with SS in the methanogenic reactor. Although TAcoD 1 produced bio-methane yield and potential energy of 56.18% and 1.6-fold higher than TAcoD 2, the economical valorization of TAcoD 2 was 9-fold of that from TAcoD 1. The supernatant quality of TAcoD 2 was far better than TAcoD 1, since the SCOD, total nitrogen (TN), and total phosphor (TP) removal in TAcoD 2 and TAcoD 1 were 94.3%, 79.4%, 90.7%, and 68.9%, 28%, 46%, respectively. In terms of solid waste management, the modified TAcoD converted FW to organic fertilizer and achieved a solid reduction of 43.62% higher than that of conventional TAcoD. This new modification in two-phase anaerobic co-digestion of food waste and sewage sludge provides a potentially feasible practice for simultaneous bio-methane, organic fertilizer, and high supernatant quality achievement. The online version contains supplementary material available at 10.1007/s40201-020-00603-8.

Co-digestive performance of food waste and hydrothermal pretreated corn cob

Anaerobic co-digestion of lignocellulosic biomass and food waste (FW) has been extensively applied. However, whether hydrothermal pretreatment (HTP) of lignocellulosic biomass can enhance the performance in co-digestion deserves further investigation. In this study, corn cob (CC) was adopted as a typical lignocellulosic biomass for co-digestion with FW at different VS ratios of 1:3 (S1–S4) and 1:6 (S5–S8), attempting to evaluate the effect of HTP of CC at different temperature gradients (125, 150 and 175 °C) on the co-digestion performance. The emphasis was placed on hydrolysis, acidification and methanogenesis for different feedstock conditions. Results illustrated that the HTP had a certain destroying effect on the lignocellulose structure in CC and the crystallinity of cellulose decreased, significantly facilitating its co-digestion with FW. For FW/CC co-digestion at the VS ratio of 1:3, the S3 group (CC was pretreated at 150 °C) reached the maximum cumulative biogas yield (CBY) of 4660 mL and the maximum specific methane yield (SMY) of 316.9 mL/g·VS. Moreover, at 1:6, S7 group (pretreated at 150 °C) exhibited the optimal CBY of 4100 mL while achieving the SMY of 277.6 mL/g·VS among the digesters, indicating that the co-digestion of pretreated CC and FW could achieve higher methane production, and 150 °C refers to the optimal pretreatment temperature. Moreover, the peak values of the accumulated VFAs in digesters S1–S4 (2000–3000 mg/L) is higher than that in digesters S5–S8 (800–1500 mg/L). As suggested from microbial community and diversity date, the HTP expedited the enrichment of system hydrolyzing and acidogenic bacteria. These results are significant and provide certain guidance for optimizing the co-digestion of FW and CC in actual engineering.

Solid-state anaerobic co-digestion of food waste and cardboard in a pilot-scale auto-fed continuous stirred tank reactor system

Abstract Increasing volume of Food waste (FW) and cardboard (CB) which are the two major fractions of municipal solid waste increases environmental concerns. This study evaluated the performance of a pilot-scale auto-fed continuous stirred tank reactor (CSTR) system for the solid-state anaerobic co-digestion (ACoD) of acetic acid rich food waste (FW) and cardboard (CB). The objective to co-digest acids rich FW and CB originates from the fact that acetic acid can act as a pre-treatment agent. Can the frequency of feeding and feeding pattern assists the system to withstand an organic loading rate >4 g volatile solids (VS)/(L.d) without addition of any pH boosting chemicals? Four mixing ratios of 100:0, 80:20, 60:40, 50:50 (v/v %) of FW and CB on biogas yield and process stability at an OLR > 4 g VS/(L.d) at a hydraulic residence time (HRT) of 40 d was investigated. Results revealed that the reactor R1 operated with FW:CB in the ratio of 100:0 achieved 76% biodegradability (the ratio of experimental to theoretical methane yield) while it was 39%, 32% and 22% for FW:CB ratios of 80:20, 60:40 and 50:50, respectively. This study concludes that exposing the CB to acetic acid-rich FW assisted the disintegration and depolymerization of CB without any pre-treatment step. Micro-feeding the reactor on an hourly basis assisted to overcome the susceptible failure of the system. The outcomes of this study provides new insight into the potential of implementing decentralized AD units for the treatment of FW and CB at source, which not only diverts waste from landfills but creates a revenue model through bioenergy generation and digestate sales.

Effect of Agitation on Anaerobic Co-Digestion of Swine Manure and Food Waste

The synergism of food waste associated with swine manure can provide an increase in biogas production, besides promoting greater stability in the anaerobic co-digestion process. To verify this effect, co-digestion tests were performed in two reactors, one with agitation, and the other without agitation. In both systems, gasometers were used to measure biogas production in an experiment lasting two hydraulic retention times (HRT). On each feeding day, the temperatures of the ambient and of the effluent taken from the reactors were measured, and samples of the food waste and effluent were collected to perform analysis of pH, total solids (TS), volatile solids (VS), fixed solids (FS), volatile acidity (AV), and total alkalinity (TA). In addition, the chemical oxygen demand (COD) was determined every five days, and gas composition was determined at the beginning of the second HRT. As important results, in both reactors a decrease in pH was verified due to the weakening of the buffer effect of the medium. This was due to the low alkalinity found in the food waste, causing an increase in acidity in the contents of the reactors. The volume of biogas produced was higher in the reactor with agitation, which meant an increased efficiency of the process. Finally, a low methane content was verified through chromatographic analyses, indicating a reduction in the activity of the microorganisms present in the medium. Thus, it is concluded that agitation linked to anaerobic co-digestion of swine manure with food waste exerted a positive effect on biogas production.

Dry Anaerobic Co-Digestion of Highland Barley Straw and Food Waste: Anaerobic Co-Digestion Performances and Microbial Community Characteristics

Dry Anaerobic Co-Digestion of Highland Barley Straw and Food Waste: Anaerobic Co-Digestion Performances and Microbial Community Characteristics

Investigating the Effect of Crude Glycerol from Biodiesel Industry on the Anaerobic Co-Digestion of Sewage Sludge and Food Waste in Ternary Mixtures

This work evaluated the production of biogas and methane (CH4) through the anaerobic co-digestion (AcoD) of primary sludge (PS) from sewage treatment, food waste (FW), and crude glycerol (GL). To address the effect of the latter on AcoD stability and performance, biochemical methane potential (BMP) tests were carried out at different GL concentrations (1 and 3% v/v). Control experiments with PS or PS + FW were also performed. A modified Gompertz model was used to describe biogas/methane production behavior. The results demonstrated that small increases in the organic load resulting from glycerol addition led to significant increments in biogas and methane production. Although methanogenesis was transiently inhibited in the BMP trials with the highest GL concentration, implying a longer adaptation period for methanogenic archaea, methane production was restored and even maximized under these conditions. The biogas yield amounted to 432.4 and 692.6 mL/gVS (removed) at 1% and 3% GL, respectively, while the methane yield corresponded to 343.3 (1% GL) and 525.7 mLCH4/gVS (3% GL). The latter represent increases of 45.4% and 122.7% compared to those achieved with PS+FW. Finally, the energy potential from the AcoD of the ternary mixture was estimated to evaluate its contribution to electricity supply in Brazil.

Anaerobic Co-Digestion of Sugarcane Leaves, Cow Dung, and Food Waste: Focus on Methane Yield and Synergistic Effects

Anaerobic co-digestion (AcoD) of food waste (FW) and lignocellulose waste for methane production is a promising technology. This work investigated the methane generation from AcoD of FW, sugarcane leaves (SL), and cow dung (CD) under mesophilic condition in a batch test. As for AcoD of two feedstocks (SL and FW or CD and FW), introduction of SL and CD (25%, volatile solid (VS) basis) showed slight improvement in methane production from FW. In contrast, positive synergistic effect (synergy index=1.03–1.14>1) was observed in all the AcoD reactors of the three feedstocks (SL, CD, and FW). The optimum mixing ratio of FW:SL:CD (VS basis) was 85:11.25:3.75 with a synergy index of 1.07, achieving a methane yield rate and methane content of 297.16 mL/g VS and 73.26%, respectively. This methane production rate was 110.45% and 444.72% higher than mono-digestion of SL and CD. The biodegradability, soluble chemical oxygen demand (SCOD), and VS removal rate are 56.44%, 44.55%, and 55.38%, respectively. The optimum results indicate that AcoD of FW, SL, and CD have higher potentials for energy recovery and providing a forceful scientific evidence for their energy utilization.

Biogas Residue Biochar Enhances Thermophilic Anaerobic Co-Digestion of Sewage Sludge and Food Waste

Biochar addition in anaerobic digestion (AD) systems generally improves the transformation of organic waste and the production of methane, yet little is known on further recycling of the biogas residue into biochar for AD. Here we prepared biogas residue biochar by heating the residue of food waste after AD at 500°C. We comprehensively compared the performance of this biochar with coconut shell biochar and corn stalk biochar on anaerobic co-digestion of sewage sludge and food waste, and explored the corresponding mechanisms. Results show that the biogas residue biochar has the highest mean methane daily yield, of 432.16 mL per g of volatile solids, versus 377.66-386.30 mL for coconut and corn biochars. This finding is in agreement with the structure of biogas residue biochar, whose structure shows more abundant functional groups, especially basic functional groups, which can effectively neutralize fatty acids and alleviate systematic acidification. Results are also supported by characteristics of the biogas residue biochar, which enriched the abundance of electroactive Clostridia , Methanobacterium and Methan o brevibacter in sludge under thermophilic condition, thus shortening the process of methanation.

Anaerobic Co-Digestion of Food Waste with Livestock Manure: A Biogas Based Circular Economy and Sustainable Development Goals

Anaerobic Co-Digestion of Food Waste with Livestock Manure: A Biogas Based Circular Economy and Sustainable Development Goals

Anaerobic co-digestion of food waste, goat and chicken manure for sustainable biogas production

Anaerobic digestion of food waste alone is not very stable due to its acidic nature and high biodegradability. Co-digestion of food waste with alkaline substrate such as chicken manure and goat manure could enhance process stability and biogas yield. In this study comparison of mono digestion of food waste with 8% total solid content at an ambient temperature and co-digestion of food waste, goat and chicken manure at ratio 5:2:3 and 2:1:1 with 8% total solid content at an ambient temperature in hilly region of Nepal were carried out. Biogas yield was highest with mixing ratio of 5:2:3 with the values of 109 ml/gVS followed by mixing ratio of 2:1:1 with the values of 80 ml/gVS. Mono digestion of food waste was not stable and broke down after two weeks of operation. Findings from this study suggests that co-digestion could be a suitable method for addressing the problem related to stability in a single substrate digestion in an ambient temperature condition. Moreover, mixing ratio of co-digestion substrates is important for improved biogas production. Co-digestion of food waste with goat and chicken manure could be a practical approach for sustainable clean energy production and waste management in context of Nepal.

The synergistic strategy and microbial ecology of the anaerobic co-digestion of food waste under the regulation of domestic garbage classification in China

With the implementation of new domestic garbage classification policy in China, attention is growing to improve the treatment efficiency of municipal ‘wet’ waste. Combing with the new regulation, the synergistic strategy and the microbial ecology of the anaerobic co-digestion (AcoD) of cooked food waste (CFW), uncooked food waste (UCFW) and rice straw (RS) were analyzed in current study. Results showed that the maximum cumulative methane yield (CMY) and synergic index were obtained when CFW and UCFW were mixed at the ratio of 1:1 (based on volatile solid content). The highest CMY 452.94 ± 0.99 mL/g-VS was obtained when the ratio of CFW, UCFW and RS was 0.81:0.09:0.10, which was 16.29%, 36.20% and 121.84% higher than their mono-digestion, respectively. The AcoD promoted the methane potential by prolonging the release time of organic matter and slowing down the hydrolysis rate. Furthermore, the AcoD increased the species diversification and relative abundance of fermentation bacteria in digesters, and Methanosaeta predominated the methanogen communities. This study demonstrated a clean and sustainable AcoD strategy for safe disposal of urban food waste and revealed the variation of microbial community, which can provide a base for efficient bioenergy recovery from urban domestic garbage.

A case study on integrating anaerobic digestion into agricultural activities in British Columbia: Environmental, economic and policy analysis.

This paper provides an example of the kind of analysis needed to support better targeted policies to reduce the environmental impacts of agricultural activities, using the specific case of Anaerobic Digestion (AD) to treat animal manure and other agricultural and food wastes in British Columbia (BC). Economic and life cycle environmental performance metrics are estimated to compare integrated and stand-alone systems using the resulting biogas and digestate. Using biogas for heating outperforms purifying it for distribution as renewable natural gas (RNG). However, current policy and energy prices in BC perversely support RNG, making biogas-fired heating systems economically unattractive. The performance of biogas-fired heating system can be improved and their dependence on subsidies reduced by integration with local agricultural activities, exploiting CO2 and digestate as by-products. Biogenic CO2, from combustion of the biogas and from mushroom cultivation, can displace natural gas use in producing CO2-enriched atmospheres to enhance growth rates in greenhouse production. Using digestate as growing media in greenhouses and mushroom cultivation can generate significant revenues but the environmental benefits are nugatory. Co-digestion of food waste can further improve performance by increasing biogas yield. With all extra benefits combined, integrated AD systems can increase both GHG mitigation and revenues by at least 80%. The analysis illustrates the general point that, to avoid perverse outcomes, policy measures must support options based on their actual GHG mitigation benefits, rather than targetting any specific technology.

Role of syntrophic acetate oxidation and hydrogenotrophic methanogenesis in co-digestion of blackwater with food waste

Blackwater collected from toilets represents a type of sustainable bioenergy resource in the modern sanitation system, while its biomethane recovery efficiencies through anaerobic digestion were limited by slow hydrolysis and inhibited methanogenesis due to a large fraction of solid organics and high free ammonia concentrations. In the current study, food waste and blackwater co-digestion was performed in an up-flow anaerobic sludge blanket (UASB) reactor (35 °C). Co-substrates with increasing food waste proportions were stepwise applied to demonstrate the threshold organic loading rate (OLR). Co-digestion effectively enhanced substrate hydrolysis efficiency by up to 86.1% and methanisation rate by up to 39.7% compared to blackwater mono-digestion. Hydrogenotrophic methanogens showed predominance in both feeding conditions. The dominant bacterial groups shifted from genus Bacteroides to T78, and methanogenic groups shifted from genus Methanogenium to Methanoculleus and Methanospirillum when the operation system shifted from blackwater mono-digestion to food waste co-digestion. The microbial community structures and the isotopic carbon analysis for CH4 and CO2 in the produced biogas indicated that a combined syntrophic acetate oxidation (SAO) and hydrogenotrophic methanogenesis (HM) pathway was established throughout the operation. The enhanced substrates’ properties including higher carbon/nitrogen (C/N) ratios and more readily biodegradable organics in food waste and blackwater co-digestion system contributed to the enhancements in biomethane recovery and microbial development compared to blackwater mono-digestion. The OLR stress under the overloaded condition negatively affected the microbial community structure and resulted in process deterioration.

Impacts of different operational temperatures and organic loads in anaerobic co-digestion of food waste and sewage sludge on the fate of SARS-CoV-2

The impacts of different operational temperatures, and organic load (OL) on the fate of SARS-CoV-2 during the anaerobic co-digestion of food waste (FW) and sewage sludge (SS) was evaluated. The lab-scaled batch reactors (i.e. R1-R7) were performed under psychrophilic, mesophilic, and thermophilic conditions and the OL of systems was 1.5, 3.5, 6 gVS/L. The performance parameters showed that at higher OL the stability of systems failed and low biogas was produced. In contrast, increasing of operational temperature of systems induced more biogas generation due to the increment of metabolic activity of bacteria. Therefore, R1-R7 achieved biogas yield of 202.5, 249, 187, 260, 246, 163, and 300 mL/gVS respectively. Both SARS-CoV-2 genes i.e. ORF1ab, and N genes were detected in the effluent of psychrophilic reactors i.e. R1, and R2, with a total concentration of 46 × 103, and 11 × 103 copies/L respectively. In R3, no viral genes were observed, when the VFAs was accumulated up to 2000 mg/L and caused a pH drop to 5.6. At the mesophilic condition, the viral concentration was significantly declined, and no viral genes were observed at an OL of 3.5 gVS/L. Furthermore, the synergistic effect of temperature and accumulation of intermediate metabolites provided a sever condition for SARS-CoV-2 survival at an operational temperature and OL of 50 °C, and 1.5 gVS/L respectively.

From anaerobic to aerobic treatment: upcycling of digestate as a moisturizing agent for in-vessel composting process

In Tunisia, there are crucial challenges facing both urban and rural areas, the most prominent of which are the production of organic waste, the need for waste treatment, the demand for water and energy and the need for a circular economy. To this end, the study was designed to develop a technical concept on closed cycle ‘biowaste to bioenergy’ treating, basically food waste (FW) through combined biological processes. In this approach, the generated digestate from FW anaerobic reactors was used successfully as a moisturizing agent for FW in-vessel composting. Four types of digestate were examined to be used as moisturizing agent (MA). The selection of the appropriate MA was achieved based on technical criteria; moisture content (MC), C:N ratio and heavy metals concentrations. The findings showed that the digestate obtained from anaerobic co-digestion of food waste and wheat straw (D1) was the most efficient AD-effluent to be added. In terms of composting process performance, the thermophilic phase of the amended reactor (A1) lasted 16 days and reached higher temperatures of about 72 °C, while the unamended one (A1) was characterized by a thermophilic temperature of around 66 °C indicating that the end products were of a pathogen-free compost. When it comes to the physico-chemical factors examined demonstrating that the biological conditions were sufficiently developed. The findings showed overall decreasing profiles during the composting period for moisture, C:N ratio as well as nitrification index (NI). From the quality-point of view, it was found that heavy metal concentrations had lower limits than those values set by German standards. Moreover, all the compost samples appeared to be stable and classified as class IV and V end product.

Stimulatory effect of magnesium supplement on anaerobic co-digestion of food waste and domestic wastewater

This study investigated the synergistic effect of anaerobic co-digestion (ACoD) of food waste (FW) and domestic wastewater (DWW) together with the magnesium (Mg2+) supplement on biogas production and organics removal. An upflow anaerobic sludge blanket (UASB) reactor was operated at 35 °C under an intermittent feeding mode (48 h feed and 48 h no feed) while batch experiments were performed for the effect of Mg2+ supplement on ACoD. In terms of chemical oxygen demand (COD) removal and methane recovery, the best performance was at 150 mg/L Mg2+ supplement where COD removal efficiency and methane content reached 83.1 ± 1.1 % and 61.4 ± 0.6 %, respectively, 13.06 % and 10.63 % higher compared to the control without Mg2+ supplement. In addition, a lower ammonia-nitrogen accumulation (661.1 ± 53.0 mg/L) was observed compared to the control (811.0 ± 44.5 mg/L), showing the Mg2+ supplement also stimulatory to the ammonia-nitrogen removal, further reducing the inhibitory effect of ammonia on the ACoD performance. Results imply a promising strategy for the successful implementation of the use of ACoD technology to the treatment of FW and DWW for the resource recovery.

A novel integrated single-stage anaerobic co-digestion and oxidation ditch-membrane bioreactor system for food waste management and building wastewater recycling

This study is to develop a novel integrated single-stage anaerobic co-digestion and oxidation ditch membrane bioreactor (SAC/OD-MBR) for food waste and building wastewater recycling. The co-digestion of food waste (FW) from a canteen with waste sludge (WS) from OD-MBR was performed with the proportion of FW:WS at 10:1 by weight. The liquid digestate from the co-digestion process was further co-treated with building wastewater in the OD-MBR system for water reuse purpose. Maximum methane content of 65.2% in biogas as well as average specific methane yield of 0.24 gCH4/gVS could be obtained with anaerobic co-digestion of food waste and waste sludge from OD-MBR with HRT of 24 h and horizontal flow velocity of 0.3 m/s. The observed main methanogen species in this co-digestion process were Methanoculleus bourgensis and Methanoculleus palmolei. For co-treatment of liquid digestate and building wastewater with the OD-MBR, it was found that HRT of 24 h and horizontal flow velocity of 0.3 m/s could achieve highest COD and nitrogen removal efficiencies. HRT can be considered as a main key parameter to promote nitrification activity inside the OD-MBR system. Moreover, treated effluent from the SAC/OD-MBR could comply with the water reuse standard for garden and landscape application in the university campus. Furthermore, the techno-economic analysis indicates that this proposed system has a high potential of total cost savings and other indirect benefits. Therefore, the prototype SAC/OD-MBR can be an alternative system for food waste management and wastewater recycling for building application.

Anaerobic co-digestion of food waste and cardboard in different mixing ratios: Impact of ultrasound pre-treatment on soluble organic matter and biogas generation potential at varying food to inoculum ratios

The aim of the present work is to investigate the impact of acetic acid assisted ultrasound pre-treatment of food waste (FW) and cardboard (CB) to overcome the barriers of substrate characteristics. Anaerobic co-digestion (ACoD) experiments were conducted with FW and CB in the mixing ratios of 100:0, 80:20, 60:40 and 50:50 at a food to inoculum (F/I) ratio of 1:1 and 1:2 to investigate its impact on biogas yield, volatile solids (VS) removal, solubilization of organic matter and the specific energy (SE) required. Results revealed that the biogas yield obtained from ultrasound pre-treated samples regardless of mixing ratio was higher at a F/I ratio of 1:2 compared to 1:1. The formation of bubbles, cavities and floc matrix significantly increased and the particle size decreased from 100 μm to 10 μm for FW:CB of 60:40 and 50:50 after pre-treatment. Ultrasound pre-treatment for 45 min was adequate for FW:CB of 100:0 and 80:20 while it was 60 min for 60:40 and 50:50 for increased sCOD between 37 % - 53 %. The VS removal efficiencies increased between 3–15 % from pre-treated samples compared to untreated. The CB mixing ratio is inversely related to SE while directly related to sCOD. Overall, during ACoD of FW and CB, the FW:CB of 80:20 gave a higher biogas yield of 471 mL/g VSadded followed by 60:40 and 50:50.

Codigestion of Food Waste with Used Lipids as Substrate Material to Produce Biogas

Anaerobic co-digestion of food wastes process is represents an active technique to enhance the production of biogas as one of the clean energy sources. The effects of adding lipids as substrate material to the food waste mixture for producing biogas by anaerobic co-digestion are experimentally investigated and evaluated at various mixing ratios in the present work. The influence of lipids and food waste (potatoes, tomato, Carrots, Cellulose) mixing ratios, digestion time and other factors on production of the biogas and CH4, CO2 and H2S percent are investigated experimentally. Seven samples of substrate mixtures (used edible oil, waste food, cow dung and water) with various mixing ratios were tested during 32 days as digestion period to investigate the influence of lipids percent compared to food waste on biogas yield. The results show that, average biogas production was in range of 100-160 ml per day and the maximum percent of Ch4 and CO2 were 52% and 46% respectively for the produced biogas. Increasing the lipids percent in the substrates mixture could enhanced the biogas and CH4 production. The mixing sample containing 70% lipids and 30% food waste percent was produced significantly higher biogas and CH4 yields compared to the other mixing samples. Best digestion time of the food waste-lipid mixtures was observed in range of 12-16 days for the tested samples. The maximum cumulative biogas was 5120 ml which was produced by substrate mixture (70% lipid and 30% solid waste) during digestion time 32 days.