Maximum Biogas Production Research Articles

Analysis of the Results of Experimental Studies of Sewage Sludge Treatment in the Biotechnology Laboratory

Background: The use of bioreactors at sewage treatment plants solves an environmental problem at water utilities in the Udmurt Republic, as sludge beds are overflowing due to the fact that tens of tons of sewage sludge have been stored on sludge beds every day since the 1980s and amount to hectares of land. Objective: The results of experimental studies on the processing of wastewater sludge in the Biotechnology laboratory were analyzed to improve the efficiency of the technological process for the disposal of organic waste using a biogas plant and a process activator. Methods: The methodology for preparing a biogas plant for entering the operating mode and further operation is presented. An algorithm for experimental studies using a biogas plant and obtaining biogas from organic waste is presented. Results: The article presents an analysis of the results of experimental studies of sewage sludge treatment under periodic psychrophilic and, subsequently mesophilic operating conditions of the bioreactor in relation to the climatic conditions of the Udmurt Republic. The results of experimental studies in the article are presented in the form of graphical dependencies of the volume of produced biogas on the temperature and duration of the process. Results: The article presents the dynamics of changes in the volume of produced biogas depending on the increase in temperature and duration of the process under the mesophilic operating mode of the bioreactor. On the first day of the experiment under the mesophilic mode in the bioreactor, the volume of produced biogas was 2.15% (7.41 g) at a temperature of 32 ° C; with increasing temperature, the volume of produced biogas increased. The maximum biogas production was observed on the fifth day of the experiment under the mesophilic mode and amounted to 7.66%, which corresponds to 26.41 g. Conclusion: The recommended loading volume of biomass into the bioreactor is 80 liters. In accordance with the actual conditions of the sewage treatment facilities, the volume of biogas produced will be 26,000 m3 of methane daily during the period of anaerobic fermentation in the bioreactor. To solve the environmental problem, it is necessary to install a complex of bioreactors at the water utilities of the Udmurt Republic.

Maximizing biogas production from expired dairy products: A two-stage anaerobic digestion approach

Maximizing biogas production from expired dairy products: A two-stage anaerobic digestion approach

Evaluation of additive effecton anaerobic sewage sludge digestion

An additive based on iron oxides was applied to reduce the amount of produced sludge and to increase the production and quality of biogas. The C/N ratio was 11.0–11.3 and the pH of the sludge mixture was 7.3 before the anaerobic digestion. The determined optimal dose of the additive was 0.35 g/g of sludge dry matter over 20 days. This allowed a reduction in the sludge retention time up to 6–11 days. Consequently, maximum biogas production was reached on average 1.6 times faster, volatile solids degradation increased by 56.7%, biogas production increased by 75%, specific biogas production increased by 11.5%, and methane concentration in the biogas increased by 8.4%–18.2%. When the additive was applied, the quantity of phosphate phosphorus in the supernatant was reduced by up to 19%, and hydrogen sulfide reduction efficiency in the biogas ranged between 55% and 62%. In sludge treatment facilities, using an iron oxide-based additive could reduce the dewatering and drying costs for digested sludge by up to 35% .

The Effect of the Mixing Ratio of Sewage Sludge and Organic Fraction of Municipals Solid Waste on Biogas Production in Anaerobic Digestion Process

Anaerobic digestion was the best way to treat organic waste biologically. It uses microorganisms to biodegrade biosolids without oxygen, producing biogas and compost. The study involved conducting batch experiments to investigate biogas and fertilizer production. Three digestive systems (A, B, and C) with three different mixing ratios were operated simultaneously and had a retention time of thirty-five days. The organic fraction of municipal solid waste, sewage sludge, and bacteria were employed in the experiments. The Al-Rustamiyah wastewater treatment plant was the source of the sewage sludge. The organic municipal solid waste fraction was utilized as materials, including fruit peels, rotten fruits, vegetable peels, eggshells, rotten vegetables, and garden leaves. The bacterial strain used in this research was E. coli, isolated directly from the local sewage sample and selected as an eco-friendly bacteria after conducting many tests. The digester's initial temperature was 30 °C, and it reached a high of 42 °C on the 16th day. Three digesters had initial pH values (6.7, 6.3, 6) and final values (7.3, 7.1, 7). The results showed good anaerobic digestion performance. The digester (C) achieved the highest biogas production, with a maximum cumulative biogas production value of 0.0549 m3. It also demonstrated removal efficiencies of 78.30% for TS, 89.13% for VS, 86.36% for BOD5, and 80.5% for COD. Additionally, the moisture content was measured at 43.30%. The anaerobic digestion’s final product was used as a high-quality fertilizer.

Estimation and Control of WRRF Biogas Production

The development of resource-efficient digital technologies is a critical challenge in the wastewater sector. This industrial case study, conducted in collaboration with the Veas Water Resource Recovery Facility in Norway, focused on creating data pre-processing methods and resource-efficient control strategies. Using data from the Veas biogas plant, dynamic models were developed to compare control outcomes. The primary objective was to maximize biogas production and hot water usage while maintaining optimal temperature and hydraulic retention time by adjusting inlet sludge and hot water flow rates. Sequential operations were approximated as continuous operations using a 30-min moving minimum/maximum for bimodal data and a 2-h moving average for noisy data. The data-driven dynamic models achieved an accuracy of up to R2 of 0.85. The control strategy, which included one feedback controller, one ratio controller, and flow rate restrictions, was compared to real production data (baseline) and tested across six scenarios. The best improvement over the baseline scenario resulted in a 3% increase in total biogas production, a 6% increase in total organic loading, a 13% increase in hot water use, and a one-day reduction in hydraulic retention time. Future work should focus on control studies using extended datasets and nonlinear models.

Syntrophic relationship among microbial communities enhance methane production during temperature transition from mesophilic to thermotolerant conditions

Hydrogenotrophic methanogenesis, in a syntrophic relationship with fermentative and acetogenic bacteria, is an essential key for maximizing biogas production and reducing CO2 emissions. However, its impact on CH4 production under varying temperatures is not widely understood. This study investigates the effects of incremental temperature transition from 37 °C to 45 °C at 2 °C intervals, on anaerobic digestion (AD) using digested sewage sludge with low glucose addition. Results showed CH4 production levels of 298 and 309 ml CH4/g CODfed at 37 °C and 39 °C, respectively, and exhibited a decrease at 41 °C. A temperature increase to 43 °C restored CH4 production to 260 ml CH4/g CODfed, with lower CO2 output. At 45 °C, the CH4 - CO2 production gap widened, indicating enhanced methanogenic activity due to prolonged high temperatures. Methanothrix was the predominant methanogen, followed by Methanobacterium whose activity increased at 43 °C and 45 °C alongside the upregulation of key hydrogenotrophic pathway enzymes (fwd, ftr, mch). The increasing abundance of fermentative bacteria at 43 °C and 45 °C may upregulates hydrogenotrophic methanogenesis. Flux balance analysis revealed the role of Acetomicrobium and Clostridia sp. strains that supplied the most acetate, providing approximately 7 – 600 mmol/gDW/h to the microbial communities. These findings highlight the adaptability of microbial communities and possible syntrophic relationships in response to temperature changes, demonstrating the resilience of AD processes under varying environmental conditions.

Performance Monitoring of Greenhouse Biogas Digester

The country of South Africa is facing an energy crisis due to heavy reliance on fossil fuels, resulting in continuous load shedding. The use of renewable energy technologies can help resolve the current electricity crisis in the country. Moreover, waste-to-energy conversion has the potential to greatly contribute to economic development and improve public health. One such technology is biomass, which exploits waste-to-energy conversion. Additionally, solar energy can be utilized to maintain appropriate digester temperatures for optimal biogas yield. The study aims to assemble a portable balloon biogas digester in an enclosed greenhouse cavity and feed it with cow dung. Daily monitoring of pH and temperature (ambient, greenhouse, and slurry) was conducted, while biogas yield was monitored using a serial residential diaphragm flow meter. Furthermore, the composition of methane was monitored using the SAZQ biogas analyzer. The study investigated the impact of temperature on biogas production. The results revealed that the gas production rate of biogas fermentation increased within a certain temperature range. Therefore, maximum biogas production was achieved at a pH of 6.84 to 7.03, and the composition of methane exceeded 50%. Consequently, the study concluded by indicating that the digester housed within a greenhouse envelope, as demonstrated in this novel study, maintains the temperature within the optimal mesophilic range necessary for anaerobic digestion.

Bioenergy recovery from waste engine oil through anaerobic co-digestion with sewage sludge: Effects of total solids and inoculum to substrate ratio

ABSTRACT Considering their various benefits, such as pollution control, waste management, and eco-friendly energy production, much more attention is currently devoted to utilization of some urban, industrial, and agricultural wastes in the course of anaerobic digestion (AD) across the world. From this perspective, the present study aimed to evaluate prospects of biogas production from waste engine oil (WEO) through its co-digestion (CoD) with activated municipal sewage sludge (SS). In order to do this, AD was carried out in batch-mode 1-L reactors at a mesophilic temperature of 35°C, with consideration for total solids (TS) levels of 3% and 6% and inoculum-to-substrate ratios (ISRs = 0.5, 1, and 2), which were based on volatile solids (VS), over a period of 85 days. The treatment with TS = 6% and ISR = 2, or 6874 mL, showed the maximum biogas generation rate, according to the trials, with TS and VS removal values of 23% and 28%, respectively. As well, reactor monitoring during AD revealed that the parameters of potential of hydrogen (pH) and alkalinity recovered following acidification after 7 days, and the relatively low efficiency of the given process (0.233 m3/kg-VSadded) was attributed to the highly complicated and difficult-to-degrade structure of WEO. The kinetics of anaerobic CoD consistently established that the maximum cumulative biogas production rate (Rm = 5.61 m3/kg-VSadded.d) and the shortest biogas production lag time (λ = 0) occurred when there were TS = 3% and 6%, in that order. Moreover, kinetic models, i.e. the Modified Gompertz and Logistic Function ones, were found to be in very good agreement with experimental data, whereas the first-order model failed to offer ideal predictions of biogas production trend in most cases.

Improving biogas production with application of trimetallic nanoparticle using response surface methods

The potential of trimetallic nanoparticles (TMNPs) to enhance biogas production through microbe-to-microbe interactions and boost biogas yield is evident. This present study employed the central composite design (CCD) of response surface methods (RSM) to determine the optimal conditions of iron-cobalt-zinc TMNPs influenced anaerobic digestion for higher biogas yield. The impact of initial pH (6.6–7.4), TMNPs concentration (0–30 mg L−1), temperature (25-45 °C), and hydraulic retention time (HRT) (0-4 days) were modelled for improved biogas production. The results indicated that the linear model terms of pH and TMNPs concentration, and quadratic model terms of temperature and HRT, significantly affect the biogas production. Linear model terms of TMNPs, temperature, pH, and HRT have significant interactive effects and the numerical analysis identified the best conditions for the evaluated parameters. Ideal anaerobic process settings generated a maximum cumulative biogas production of 3700 mL−1POME than blank (2000 mL−1), corresponding to an 85 % yield. Optimizing the initial pH, TMNPs concentration, temperature, and HRT can significantly improve biogas yield and could be helpful for developing more efficient AD processes at large volume and commercial biogas plants. Promoting TMNPs as catalysts positively improves an AD process towards sustainable biogas production.

Synergizing sugarcane waste valorization: Optimization of two-stage anaerobic co-digestion for enhanced methane recovery and organic matter removal

Multiple strategies have been used in anaerobic digestion of effluents aiming to enhance the efficiency of the methane (CH4) recovery process, where co-digestion and the two-stage process emerge as prominent methods. In this context, this study aimed at evaluating the co-digestion of sugarcane vinasse and molasse in a two-stage process using anaerobic fluidized bed reactors (AFBR), verifying the effect of increasing the organic loading rate (OLR) (5–22.5 kg COD.m−3.d−1) and temperature in the second stage methanogenic reactor. Regarding the two-stage process, sugarcane vinasse and molasses fermentation demonstrated the maximum energy potential (E.P) of 57.08 kJ.d−1 (7.5 g COD.L−1). Regarding the methanogenic sequential reactors, organic matter removal reached high values (up to 84.5 % in a thermophilic sequential reactor (TSR); up to 84.5 % in a mesophilic sequential reactor (MSR)). The highest CH4 yield (MY) of 306.77 ± 38.84 mL CH4.g−1 COD rem was observed in MSR (9 kg COD.m−3.d−1). Meanwhile, the maximum value of MPR (3.8 ± 0.5 L CH4.L−1.d−1) was observed in TSR (21 kg COD.m−3.d−1). Regarding the Archaea domain, a predominance of hydrogenotrophic microorganisms could be identified, in which the genera Methanobacterium and Methanothermobacter were the most abundant in MSR and TSR, respectively. This study demonstrates that anaerobic digestion of sugarcane vinasse and molasses enhances anaerobic treatment using two-stage AFBRs. It not only produces CH4 but also generates hydrogen and high-value products through an acidogenic reactor. This research marks a significant advancement in managing sugarcane processing by-products, offering promising approaches to maximize biogas production and improve pollutant removal efficiency.

A new concept for bioenergy yield in anaerobic digestion process: Highlighting current yield challenges

The development of sustainable energy sources including biogas produced from urban and industrial wastes has received much attention over the past few years. Given that biogas can be an alternative to fossil fuels before long, its yield, representing the value of energy production from the substrate, has been of utmost importance. With reference to the current definition, biogas yield simply depends on the maximum biogas produced per unit mass of the substrate. In this line, anaerobic digestion (AD) is a time-consuming process, whose duration affects the biogas production yield as well as the maximum biogas production rate. Against this background, the present study dedicated focus on the time factor to present a new definition of biogas/methane (CH4) production yield in AD. In light of this, the time entailed for the AD process (T95%), including the lag phase time (Tlag), the time in proportion to the logarithmic production of biogas (Tlog), and the biogas stabilization time (reaching 95 % of the maximum biogas production rate, T→95%) were taken into account. In accordance with previous research, four modes, viz., (i) equal maximum biogas-different time, (ii) different maximum biogas-equal time, (iii) different maximum biogas-different time (receding yield) and (iv) different biogas maximum-different time (approaching yield) were assessed. For this purpose, the kinetic models, namely, modified Gompertz (MG) and logistic function (LF), were recruited to determine the maximum biogas production rate (Rm) and the lag phase time (λ). Among the mentioned modes, the yield difference between the samples investigated according to the current and time-based yields was 24 % on average, and reached 85 % in the first and third modes. Evaluating the data from 32 studies, using the Python programming language, correspondingly revealed that the correlation coefficient between the AD process time (T95%) and the current and time-based yields augmented from 7 % to 51 %. This demonstrated the impact of the time factor on the biogas yield. Based on the MG model, the significance level of the Rm parameter increased from 52 % to 94 %, highlighting the value of the logarithmic phase time of biogas in the AD reactor.

Silver nanoparticles incorporated with superior silica nanoparticles-based rice straw to maximize biogas production from anaerobic digestion of landfill leachate

Treating hazardous landfill leachate poses significant environmental challenges due to its complex nature. In this study, we propose a novel approach for enhancing the anaerobic digestion of landfill leachate using silver nanoparticles (Ag NPs) conjugated with eco-friendly green silica nanoparticles (Si NPs). The synthesized Si NPs and Ag@Si NPs were characterized using various analytical techniques, including transmission electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy. The anaerobic digestion performance of Si NPs and Ag@Si NPs was tested by treating landfill leachate samples with 50 mg/L of each NP. The results demonstrated an enhancement in the biogas production rate compared to the control phase without the nanocomposite, as the biogas production increased by 14% and 37% using Si NPs and Ag@Si NPs. Ag@Si NPs effectively promoted the degradation of organic pollutants in the leachate, regarding chemical oxygen demand (COD) and volatile solids (VS) by 58% and 65%. Furthermore, microbial analysis revealed that Ag@Si NPs enhanced the activity of microbial species responsible for the methanogenic process. Overall, incorporating AgNPs conjugated with eco-friendly green Si NPs represents a sustainable and efficient approach for enhancing the anaerobic digestion of landfill leachate.

The effect of raw material (cow and chicken manure) and reactor type for improving and maximizing biogas production.

Biomass energy is a type of renewable energy and animal waste is one of the main resources for its production. The purpose of this study is to investigate the effect of raw material type (cow and chicken manure) and the type of reactor (digester) on the biogas produced by measuring the amount of methane in the product. Three types of digester (metal, simple PVC, and PVC with leachate rotation) with the same volume (10 L) were prepared. Equipment was installed on the digesters to measure the pH and volume of produced gas. The experiments were carried out in controlled temperature conditions (28-30 °C) and in two stages. The first experiment was to load the digesters with cow excrement, and the second experiment was to load the digesters with chicken excrement. In both experiments, the digesters were fed with 1.5 kg of animal manure and water with a ratio of 1:1. During a period of 60 days, the volume of biogas and methane produced was measured and recorded. The results showed that the amount of biogas produced from chicken waste is more than the amount obtained from cow waste. However, the amount of methane produced using cow excrement was more than that of chicken excrement. Also, the performance of PVC digester with leachate rotation was better than the other two digesters, which could be due to the mixing of raw materials in this type of digester.

Design and production of an automatic temperature regulation system for a biodigester (Republic of Guinea)

Automatic temperature regulation system is crucial to optimize the anaerobic fermentation process and maximize biogas production. In this study, we implemented an automatic system integrating GSM technology to enable remote temperature control and regulation. For this, we installed a temperature sensor inside the biodigester in order to monitor these thermal variations, the data collected by this sensor is transmitted to the central control system via an Arduino Uno module. The latter compares the received data with predefined thresholds and accordingly sends adjustment commands to the heating system. Operators can monitor and adjust temperature parameters remotely via SMS messages through the SIM800 GSM module. Through this system, the temperature of the biodigester can be maintained at optimal levels, thereby promoting efficient digestion of organic materials and continuous production of biogas, while providing convenient and responsive remote management.

A REVIEW OF AQUATIC PLANT BIOMASS PRETREATMENT METHODS FOR BIOGAS PRODUCTION

The increasing global demand for renewable energy sources has led to interest in generating biogas from aquatic plant biomass. This research examines the pretreatment methods of biomass, aiming to enhance the efficiency of biogas production processes. The analysis presents mechanical, chemical, biological, or combined pretreatment techniques, assessing their respective advantages, limitations, and potential synergies. The review extends beyond individual methodologies to identify potential synergies or sequential applications that could maximize biogas production efficiency. This study ultimately facilitates moving the field forward, contributes to the transition to more sustainable energy solutions, identifies gaps in existing researches, paving the way for future investigations and combat to solve upcoming energy problems.

Introduction of Plug-flow Anaerobic Sludge Blanket (PASB) reactor for wastewater treatment

Plug-Flow Anaerobic Sludge Blanket Reactor (PASB) was used as the experimental reactor for the treatment as a replacement for Up-flow Anaerobic Sludge Blanket Reactor (UASB). The novelty of this study is to analyse the applicability of a novel post-treatment for anaerobically treated water by modifying UASB reactor which might be cost-effective, sustainable, and time-saving in the field of anaerobic treatment. Low-strength and high-strength (Leachate) wastewater (WW) were anaerobically treated under ambient temperature (28ºC-32ºC) with different Hydraulic Retention Time (HRT) values using a PASB and UASB setup. Chemical Oxygen Demand (COD) removal efficiency, biogas production rate, and gas composition were recorded and analysed. The average influent COD concentration of the low-strength wastewater was about 2070 ± 70 mg/L during the operation period of the reactor, and the COD removal efficiency of PASB was 90 ± 0.2 % which was 16 % enhancement at 10 h (hrs) HRT compared to UASB. The maximum biogas production recorded at this HRT was 13.72 ± 0.16 mL/h/L, which was 30.7 % higher than UASB. For leachate, COD concentration was about 6270 ± 220 mg/L, and COD removal efficiency was 97.2 ± 0.2 %. It is about a 23 % increase compared to UASB, at 8 hrs HRT and the maximum biogas production rate obtained for leachate treatment was 71.57 ± 1.53 mL/h/L and it was 30 % escalation than UASB. Hence, the PASB Reactor seems to be a desirable technique in compared with UASB to reach a comprehensive treatment efficiency, with efficient biogas exploitation to meet goals of renewable energy especially in tropical nations where less reactor heating is needed.

Maximizing biogas production from leftover injera: influence of yeast addition to anaerobic digestion system

Abstract Injera is a staple food in Ethiopian dine. This study aimed to investigate on leftover injera (LI) for producing biogas via anaerobic digestion (AD), while leftover injera is full of easily biodegradable components. Aiming to examine the impact of yeast addition on biogas production efficiency, it was found that the addition of 2 % volatile solids (VS) of stimulated yeast, daily biogas output increased by 520 and 550 ml after 12 and 37 days of anaerobic digestion, respectively, with rather steady biogas production. The rate at which gas production increased was drastically cut in half when yeast was left out of the control group. Biogas production increased by only 60 ml despite the addition of two portions of substrate and yeast. Biogas output in the yeast group after fermentation was also up 33.2 % compared to the control group. The yeast group’s anaerobic digesting system was more stable, as determined by the study of markers including volatile organic acids, alkalinity, and propionic acid. The findings can be used as a benchmark for future trials aiming to industrialise continuous anaerobic digestion, allowing for more flexible response to feed as waste LI as organic load.

Biogas Production from the Potato Peel Waste: Study of the Effect of C/N Ratio, EM-4 Bacteria Addition and Initial PH

Objective: The objective of this study was to examine the effect of the C/N ratio, EM-4 addition and initial pH on the yield of biogas from potato peels. Theoretical Framework: In this topic, the concept and theory of biogas production from potato peels on a laboratory scale is presented, then the best conditions and kinetic constants are studied using the Gompertz model. Method: The variables in this study were the C/N ratio of 25 and 30, the EM-4 addition of 10%v/v, and initial pH of 6.8 and 7. This research was conducted on laboratory scale digesters under batch system. This study also discussed the kinetics of biogas production using the modified Gompertz model. Results and Discussion: The results showed that the C/N ratio of 30 produced a more biogas yield 17.6-26.1% compared to the C/N ratio of 25. The addition of EM-4 bacteria resulted in a more biogas yield 17.8-23.4% compared to the without addition case. The initial pH of 7 resulted in a more biogas yield 26-29% compared to the initial pH of 6.8. In kinetic analysis, the C/N ratio of 30, with EM-4 addition of 10% and initial pH of 7 resulted the greatest values of the maximum biogas production (A) which was 6,570.24 mL/grTS and the biogas production rate (U) which was 168.56 mL/grTS.day and resulted the lowest value of the minimal biogas formation (λ) which was 13.69 days, with R2 = 0.998. Research Implications: The practical and theoretical implications of this research are discussed, providing insight into how the results can be applied or influence practice in the field of renewable energy in the form of biogas from potato peels. Originality/Value: This research contributes to the literature by presenting the concept of biogas production using potato peel as raw material. The relevance and value of this research is proven by the C/N ratio, EM-4 bacteria and pH were proven to increase the productivity of biogas from waste potato peel.

Assessing the impact of alkali pretreatment of rice husk on its composition and product portfolio: Tradeoff between biogas and valuable materials recovery for sustainability

The burning of agricultural crop residues has evolved into a significant global issue with far-reaching implications for public health and environmental integrity. Utilizing biochemical methodologies to valorize these residues presents a dual advantage, mitigating disposal challenges while concurrently fostering wealth generation through bioenergy production and the creation of value-added materials. Nevertheless, the biodegradation of residues faces impediments due to the presence of recalcitrant silica and lignin. To assess the efficacy and elucidate the performance of biochemical approaches, this study investigates the impact of NaOH treatment (2%, 4%, 6%, 8%, and 10% w/v) on rice husk (RH) at 90 °C for 2 h initially followed by anaerobic digestion (AD) for biogas generation. This recovers silica, yielding residual pulp devoid of lignin, a raw material for biogas generation. Analytical investigation through FE-SEM reveals mild fissures and surface ruptures in 4% NaOH-treated RH, while XRD shows a crystallinity index increase from 43.3% (untreated RH) to 69.4% (NaOH-treated RH). The optimal NaOH concentration, yielding 0.16 g/g of silica and 0.206 L/g VSadded of biogas is 4%. These results highlight tailored NaOH's potential for enhancing silica recovery and biogas production from RH. Spearman's correlation analysis reveals a strong correlation (0.9–1.0) among the reduction in volatile solids (VS %), total solids (TS %), methane yield (mL/g VSadded), and biogas yield (mL/g VSadded). P values for artificial neural network (ANN) and fuzzy models consistently range from 10−4 to 10−19. Achieving sustainability necessitates balancing the trade-off between maximizing biogas production and optimizing silica recovery for an environmentally sound and efficient system.

Biogas Production from the Paddy Straw Pretreated with Sodium Hydroxide and Co-Digestion with Cow Manure

Paddy straw waste (PS) is an organic waste that is disposed in open land after preparation of rice harvest that is generated in equal or greater quantities than the rice itself. Generally, it is disposed in open land, which increases anthropogenic gases. Converting it into useful energy or value-added products may reduce disposal problems and anthropogenic activity. In this study, PS with different treatments of sodium hydroxide (NaOH) at 2, 4, 6 , 8 and 10% was co-digested with cow dung (CD) for obtaining biogas by anaerobic digestion. For this purpose, PS was mixed with CD at different proportions, namely 50:50, 40:60, 30:70, 20:80, and 0:100 percentages on a mass basis, the samples were used in five different anaerobic digesters. The samples were kept in different anaerobic digesters for the study. The effect of important input parameters like pH and Carbon to Nitrogen (C/N) ratio on the biogas production was studied. Maximum biogas production was obtained from the co-digestion of the substrate containing 30% ps and 70% Cd for a digestion time of 20 days, and d3 shows a max pH value of 7.16. Further, the biogas collected from the digesters was characterized to ensure suitability for use as a renewable fuel. Furthermore, the digested slurry was also analyzed for its use in agriculture. The results are presented in this paper.