Efficiency Of Bioreactor Research Articles

Nonlinear effects of partitioning and diffusion limitation on the efficiency of three-layer enzyme bioreactors and potentiometric biosensors

The nonlinear effects of the partitioning and diffusion limitation on the efficiency of enzyme-based bioreactors and potentiometric biosensors are investigated analytically and numerically using a three-layer mathematical model involving the Michaelis–Menten type reaction in the transient and steady states. Analytical expressions of the steady state substrate and reaction product concentrations and the bioreactor effectiveness as well as biosensor output potential are presented for the first and zero-order reaction rates. Mathematical modelling of the diffusion limiting membrane and the conditions under which the same values of the steady state characteristics are obtained when simulating the treated system at different values of the diffusion and distribution coefficients are investigated. The effective diffusion coefficients in the total diffusion layer consisting of the diffusion limiting membrane and the outer diffusion (Nernst) layer are applied to reduce the three-layer model to the corresponding two-layer model. The dynamics and behaviour of the substrate consumption rate, product emission rate, effectiveness factor and the output potential are numerically investigated.

Design and implementation of closed-loop water reuse systems in urban and industrial settings for maximizing resource recovery and minimizing waste

Global demand for water while the freshwater sources are diminishing, it is necessary to find feasible solutions based on sustainable usage of resources. The goal is to provide beneficial use of as many resource constituents as possible with as little effluent discharge as possible leveraging innovations in treatment technologies and systems. Parameters of discussion include the operation and efficiency of membrane bioreactors, different kinds of oxidation, and reverse osmosis technologies. Such technologies are instrumental in improving the quality of water as well as enabling recovery of useful resources from the streams of wastewater that are normally obtained from several processes. This paper also assesses the feasibility of resource recovery closed-loop systems to measure its economic benefits determinable by operational expenses, energy usage and possible revenue streams from the recycled materials. Such knowledge synthesizes the findings of prior studies in the literature and emerging technologies that help to support this research and identify the impact that closed-loop water reuse systems can have. This emphasizes on the need to have proper regulatory status and consumer’s involvement for its general adoption and practicable implementation. In the long run, the integration of the systems explained above will definitely advance a sustainable water management system that will help in the stewardship of the environment and ensure that in case of arising challenges globally the country will be able to cope.

Pilot study on ceramic flat membrane bioreactor in treatment of coal chemical wastewater

Some toxic and refractory pollutants in coal chemical wastewater can penetrate the biochemical treatment systems and cause high concentrations of suspended solids in the effluent, which may obstruct the subsequent advanced treatment. In this project, a submerged ceramic plate membrane system was integrated to the last oxic corridor of an existing multistage anoxic/oxic tank. In the ceramic flat membrane bioreactor, the influent chemical oxygen demand (COD) was 102.24–178.88 mg/L, with a removal ratio of approximately 30%. The NH3–N concentration in the effluent was relatively stable with an average value of 1.76 mg/L. The turbidity of the effluent was in the range of 0.235–0.852 NTU and was stable below 1 NTU. A flux of 30 L m−2·h−1 could meet the requirements of the pilot test. A gas-water ratio of 50:1 was found optimal. When the concentration of mixed liquor suspended solids (MLSS) was >3769 mg/L, the extracellular polymeric substance in the mixed solution was utilized by microorganisms as a substrate. High MLSS decreased membrane fouling rate. NaClO backwashing can effectively remove pollutants without adversely affecting the treatment efficiency of membrane bioreactors.

Temporal and spatial variations in the physical and chemical properties of anaerobic granular sludge within a Pilot Spiral Symmetry Stream Anaerobic Bioreactor

Anaerobic granular sludge (AGS) determines the high performance of the bioreactor. To study the regionalization of granular sludge in the bioreactor, a Pilot Spiral Symmetry Stream Anaerobic Bioreactor (P-SSSAB) was established over 216 days, divided into three zones (I, II, and III) from bottom to top. AGS at the bottom of P-SSSAB had a higher porosity (60.35 %–83.27 %) and more suitable settling velocity (60 m/h) when the particle size range was 1.0–2.0 mm. This proved the better metabolic activity and superior settling performance in zone I than in zones II and III. In addition, the elemental composition of AGS in various zones was analyzed. The relative content of iron (5.66 %, 3.36 %, and 1.38 %, respectively) and sulfur (2.47 %, 2.19 %, and 1.49 %, respectively) in zone I, II, and III tended to decrease with the height of P-SSSAB. This also verified the better mass transfer performance and operational stability in lower zone than in upper zone. However, the monitoring of bed temperature in various zones revealed that the microbial activity in zone I was 6.7×10−12~3.5×10−2 times and 1.8×10−15~1.4×10−3 times that in zones II and III, respectively, which indicated that the unit activity of AGS in zone I was the worst. It indicated that AGS in lower zone had poor unit activity but had the highest unit capacity due to the high sludge concentration. Besides, the unit capacity of the upper zone was too weak to produce enough alkalinity to neutralize acid produced by excessive hydrolysis and acidification in lower zone, resulting in the worst treatment efficiency of the upper zone. Therefore, temperature and concentration ratios under various spatial distributions in bioreactors are vital to the overall sewage treatment stability and efficiency of bioreactors in actual engineering applications.

Engineering microalgae for water phosphorus recovery to close the phosphorus cycle.

As a finite and non-renewable resource, phosphorus (P) is essential to all life and crucial for crop growth and food production. The boosted agricultural use and associated loss of P to the aquatic environment are increasing environmental pollution, harming ecosystems, and threatening future global food security. Thus, recovering and reusing P from water bodies is urgently needed to close the P cycle. As a natural, eco-friendly, and sustainable reclamation strategy, microalgae-based biological P recovery is considered a promising solution. However, the low P-accumulation capacity and P-removal efficiency of algal bioreactors restrict its application. Herein, it is demonstrated that manipulating genes involved in cellular P accumulation and signalling could triple the Chlamydomonas P-storage capacity to ~7% of dry biomass, which is the highest P concentration in plants to date. Furthermore, the engineered algae could recover P from wastewater almost three times faster than the unengineered one, which could be directly used as a P fertilizer. Thus, engineering genes involved in cellular P accumulation and signalling in microalgae could be a promising strategy to enhance P uptake and accumulation, which have the potential to accelerate the application of algae for P recovery from the water body and closing the P cycle.

Simultaneous Organic Matter and Nitrogen Removal from Piggery Slaughterhouse Wastewater Using Bioaugmented Gaslift Membrane Bioreactor

AbstractA single bioaugmentation reactor and a side‐stream gaslift membrane bioreactor combined with bioaugmentation are conducted to treat real wastewater from a centralized piggery slaughterhouse in Vietnam. The bioaugmented reactor is inoculated with heterotrophic microorganisms (Bacillus sp.) isolated from piggery slaughterhouse wastewater. The results of a single bioaugmentation experiment show high removal efficiency of chemical oxygen demand (COD) (84.8%–97.5%) and total nitrogen (TN) (69.9%–87.2%) at loading rates of 1.28–3.89 and 0.14–0.37 kg m−3 d−1, respectively. The combined system demonstrates a significantly higher TN removal efficiency (89.0%–96.1%) (p < 0.001), more stable flux (36.0–38.4 L m−2 h−1), and transmembrane pressure (0.95–1.05 bar), and better capacity of separation of solid–liquid phases compared to the single bioaugmentation. High COD and TN removal efficiency is possibly due to assimilation and simultaneous nitrification and denitrification processes. The results of this study also indicate the feasibility and propitious efficiency of the bioaugmented gaslift membrane bioreactor for piggery slaughterhouse wastewater treatment.

Impact of gradually-achieved high phenol loads on the nitrification and COD removal performance of an MBBR fed with synthetic wastewater

ABSTRACT Phenol is a noteworthy pollutant, found in effluents of many industrial processes, like oil refining and drugs production, which can impair the treatment efficiency of bioreactors. This study evaluated the performance of phenol, COD, and nitrogen removal of an aerobic bench-scale Moving Bed Biofilm Reactor (MBBR) exposed to gradually increasing phenol content over 233 days. The reactor had Hydraulic Retention Time (HRT) set at 3 h and 40% filling degree (K1 media), and was fed with synthetic wastewater containing phenol (10, 20, 50, 100, 250 and 400 mg/L), glucose (400 mgCOD/L), and 40 mgN-NH3/L. Phenol, COD, and ammoniacal nitrogen removal averages were high – above 88%, 81%, and 82%, respectively –, even when the MBBR was exposed to the greatest phenol loads, indicating that the biofilm was able to acclimate and resist high phenol concentrations. However, the intense EPS production revealed the impact caused by phenol to the biofilm from the concentration of 250 mg/L onwards. Even though, at this concentration, the average removals of COD and phenol were 87.2% and 89.7%. The removal of ammoniacal nitrogen by nitrification was compromised, being 91.6% of the ammoniacal nitrogen removed by assimilation and only 0.35% removed by nitrification. At 400 mg phenol/L, the reactor provided COD and phenol average removals equal 88.6% and 80.9%, respectively. On the last day of operation, the removal of COD dropped to 55.4% and phenol removal was equal 49.0%. Novel microscopical evaluation of the MBBR’s biofilm revealed some negative effects of the phenol on the microbiota composition.

Modeling and calculation of the thermal balance of a pyrolysis plant for the production of alternative fuels from biomass

In this article, in order to determine the consumption of thermal energy for biomass processing, modeling and calculation of the thermal balance of a pyrolysis plant are performed. Based on these equations, the calculation of parameters such as the thermal balance for a tubular (cylindrical shape) bioreactor, the heat used, the efficiency of the tubular bioreactor, the exergy of the source fuel, the exergetic efficiency of the bioreactor, the loss of exergy to the environment, the heat transfer coefficient, etc. The heat balance calculation software is developed using the Java programming language. In addition, the article provides a comparative analysis of the technical and energy characteristics of bioenergy plants, which shows that the energy intensity of biomass processing in existing plants reaches up to 50-60% in the total heat balance

The Efficiency of Air-lift Bioreactor Using PVA-gel Carrier Materials to Treat Organic Components in Artificial Wastewater

An air-lift bioreactor using PVA-gel was used to remove organic components in wastewater treatment. The wastewater treatment system using Sequencing Batch Reactor with carrier material volume of 5%, activated sludge density of 2.5 g/L to treat artificial wastewater made from cat food (Whiskas) with initial COD content of 2,000 mg/L. After 10 days of operation, the removal efficiency of total COD, soluble COD, and achieved 92, 89, and 84%, respectively. Despite the high removal efficiencies of organic components, the output wastewater did not achieve QCVN 40:2011/BTNMT (Column B) discharge standards. Due to high concentrations of TSS and slow biodegradable organic components. The experimental system will be necessary to study the operating conditions to treat wastewater more efficiently and achieve the discharge standards to the environment.
 
 

Reeds and Reedmace Bioreactor Technique in Wastewater Heavy Metals Treatment, Rhizofiltration

Direct usage of plants to decrease pollution in groundwater and surface water, has gained popularity in both academic and applied fields. Phytoremediation is a low-cost technique and environmentally beneficial technology; heavy metals are absorbed via aquatic plants also usage aqua plants as fertilizer since Phragmites australis have the capability to regrow when harvesting. This would allow heavy metals to be removed from waterways over multiple growing seasons; there was a significant difference in the concentration of copper between reeds bioreactors before and after treatment. The concentration of Cu decreased from 4.00 to 0.0087 mg/L. The lower concentration of Cu values at end of the experiment might be due absorption of heavy metals from the contaminated media. The concentration of Zn was also lower than before planting having the lower concentration (0.0868 mg/L) in the fifth hydroponic. Reed has a high ability to reduce zinc concentration. The concentrations of Co and Cd decreased from 0.400 to 0.043 mg/L. As shown in the results, the levels of concentration of Cd in the reeds bioreactor were decreased. Also, the concentration of Mn decreased from 20 to 0.0219 mg/L. Moreover, Reedmace has the capacity to clean up contaminated water. The values of Cu concentration decreased from 4.00 to 0.0477 mg/L during the entire growth period. Zn from 20 to 0.1685 mg/L. Also, the concentrations of Co and Cd decreased from 0.400 to 0.043 mg/L. The concentration of Mn decreased from 20 to 0.0133 mg/L. The efficiency of reeds bioreactor for heavy metals removal in the following sequence: Mn (99.89%) > Cu (99.78%) > Zn (99.65%) > Co (89.2%) > Cd (86.08%). On the other hand, the sequence of removal efficiency of the Reedmace bioreactor was in the following sequence: Mn (99.93%) > Zn (99.15%) > Cu (98.81%) > Mn (89.25%) > Cd (88.40%).

Performance evaluation and substrate removal kinetics in a thermophilic anaerobic moving bed biofilm reactor for starch degradation

Abstract A laboratory-scale anaerobic moving bed biofilm reactor (AnMBBR) was installed and operated at various hydraulic retention times (HRTs) of 20 to 1.5 d with surface area loading rate (SALR) of 0.86 to 11.43 gCOD/m2/d. Synthetic starch containing desizing wastewater with chemical oxygen demand (COD) of 12.75 g/L was prepared and fed into the reactor. Monod, modified Stover-Kincannon, Grau second-order and First-order substrate removal models were used to evaluate the results of AnMBBR. COD removal efficiency of bioreactor was dwindled by increasing the SALR or reducing the HRT. Decay coefficient (Kd) and yield coefficient (Y) for the Monod model were 0.027 1/d and 1.01 mgVSS/mgCOD, respectively. Maximum substrate utilization rate (Umax) and kinetic constant (Kb) for the Modified Stover-Kincannon model were estimated as 12.57 and 15.22 g/L/d, respectively. The constants (a and b) for the Grau second-order model were found to be 1.09 and 1.31 whilst kinetic coefficient for the Second-order model and First-order substrate removal model were 1.62 and 1.55 1/d, respectively. Modified Stover-Kincannon model and Grau second-order model were found to be the best fit for experimental data with R2 value of 0.99. The findings suggest that these models can be applied to predict the behaviour of AnMBBRs on various scales.

Nickel (ii) effects on Anammox reaction: reactor performance, dehydrogenase, sludge morphology and microbial community changes

ABSTRACT Nickel (ii) (Ni2+) is considered as one of the necessary trace elements in the process of Anammox culture, but it may have toxic effects at high concentration. This study explored the long-term influence of Ni2+ on the denitrification efficiency of Anammox bioreactors. The results showed that when the concentration of Ni2+ was 0.5 mg/L, the bioreactor had the highest denitrification efficiency, while the removal efficiency of ammonia nitrogen and nitrite nitrogen gradually decreased at concentrations higher than 2 mg/L, and the removal rates of ammonia nitrogen and nitrite nitrogen were 26% and 39.81% at the end of the experiment, respectively. The NRR was decreased from 7.47 kg N/m3 d to 3.28 kg N/m3 d during the whole process. The highest concentration of microbial dehydrogenase was attained in about 40 days; in the meantime, its ability to consume organic matter was also maximized. The sludge morphology was changed from granular cluster to loose flocculant with a small number of spherical and filamentous bacteria and bacilli distributed on the surface. At the end of the experiment, both species richness and community diversity were reduced, and the proportion of the dominant bacteria Candidatus Kuenenia was also decreased from 59.89% to 36.72%.

Denitrification potential of sodium alginate gel beads immobilized iron–carbon, Zoogloea sp. L2, and riboflavin: Performance optimization and mechanism

A kind of gel beads loaded with iron–carbon powder (Fe–C), Zoogloea sp. L2, and riboflavin (VB2) were prepared through cross–linking of sodium alginate (SA) to establish an immobilized bioreactor. The optimal ratio of SA beads was adjusted by orthogonal experiment. The change of oxidation–reduction potential (ORP) and the concentration of Fe2+ and Fe3+ showed that the addition of VB2 as a redox mediator can promote denitrification. Under the optimal conditions (carbon to nitrogen (C/N) ratio = 2.0, pH = 7.0, and hydraulic retention time (HRT) = 8 h), the nitrate removal efficiency (NRE) of bioreactor reached 98.48% (1.99 mg L–1h−1). Furthermore, Fourier transform infrared spectrometer (FTIR), Fluorescence excitation–emission matrix (EEM), X–ray diffraction (XRD), and gas chromatography (GC) analysis revealed that the immobilization and denitrification of the immobilized bioreactor were excellent. High throughput sequencing also showed that Zoogloea played a vital role in nitrate removal.

In-situ pilot-scale passive biochemical reactors for Ni removal from saline mine drainage under subarctic climate conditions

Efficiency of passive bioreactors (PBRs) to treat mine drainage (acid – AMD and neutral – NMD), in northern climates, is evaluated using pilot-scale PBRs installed at the Raglan Mine (Quebec, Canada). Three reactors (PBR-AMD, PBR1-NMD and PBR2-NMD) were filled with reactive mixtures and operated (at hydraulic retention times of 2.5d and 1d, for AMD and NMD) for 48 days, 94 days and 44 days, respectively. The AMD quality was 27.6 mg/L Ni, 23.7 mg/L Fe, 2.4 mg/L Cu, and 3186 mg/L SO42−, at pH 3.6, while the NMD quality was 23.9 mg/L Ni, 0.06 mg/L Fe < 0.003 mg/L Cu, and 587 mg/L SO42−, at pH 7.2. Removal efficiencies of the PBR-AMD reactor were 93–95 % vs 53–56 % Ni (at the beginning and end of the tests, respectively), 96–99 % Fe and 99 % Cu. In the PBR1-NMD reactor, 99 % vs 83 % Ni (in 2017 and 2018, respectively) was removed, while in the PBR2-NMD reactor, 95–99 % vs 61–83 % Ni (at the beginning vs at the end, respectively) was removed. However, all bioreactors failed to meet environmental criteria. None of the bioreactors developed favorable conditions for sulfate reducing bacteria (SRB). Ni retention was likely mainly governed by sorption mechanisms on organic matter or on Fe-oxy-hydroxides. Low temperatures, combined with salinity, may explain the lack of SRB growth in the reactors and the absence of SO42− treatment. The treatment of Cu was not affected by the low temperatures and the primary mechanism of Fe removal in the PBR-AMD reactor was precipitation in the form of oxy-hydroxides.

Simulation of Biological Wastewater Treatment in Aerotanks with Moving Biocenosis

Purpose. The main purpose of the article is to develop a numerical model for the analysis of the process of biological wastewater treatment in a reactor with a mobile biocenosis. Methodology. For mathematical modeling of the process of biological wastewater treatment in a reactor with a moving biocenosis, a hydrodynamic model of a non-viscous vortex-free flow is used. We calculated the boundary conditions for the modeling equation on the surfaces of the bioreactor, solid walls, and the upper surface; at the inlet boundary; at the outlet boundary from the building. To calculate the process of movement of activated sludge and substrate in the bioreactor, a mass transfer model is used, which takes into account the convective-diffusion movement of the substrate and activated sludge. The process of biological water purification in that part of the bioreactor where there are no mobile biocenosis carriers will be calculated based on the Monod model. The process of biological water purification in the part of the bioreactor where there are mobile carriers is calculated on the basis of an empirical model in three stages. The first stage is determined using the Harremoes model. At the second stage, the rate of substrate «consumption» in the biofilm is calculated. At the third stage, the change in the substrate concentration in the zone where the biocenosis carriers are located is determined due to convective movement, substrate diffusion in the flow and its destruction in the biofilm on the carriers. The chaotic motion of biocenosis carriers in the reactor is modeled based on the parabolic diffusion equation. Finite-difference schemes are used for numerical integration of modeling equations. Findings. The software implementation of the constructed numerical model is carried out. A computational experiment to determine the efficiency of biological wastewater treatment in different parts of the bioreactor was conducted. Originality. An effective multifactorial numerical model has been created, which allows quick analysis of the efficiency of biological wastewater treatment in an aeration tank with mobile biocenosis carriers. Practical value. The created two-dimensional numerical model can be used for serial calculations at the stage of designing biological wastewater treatment systems and analysis of the efficiency of bioreactors under different operating conditions.

Hydrodynamics and Mass Transfer Analysis in BioFlow® Bioreactor Systems

Biotechnological processes involving the presence of microorganisms are realized by using various types of stirred tanks or laboratory-scale dual-impeller commercial bioreactor. Hydrodynamics and mass transfer rate are crucial parameters describing the functionality and efficiency of bioreactors. Both parameters strictly depend on mixing applied during bioprocesses conducted in bioreactors. Establishing optimum hydrodynamics conditions for the realized process with microorganisms maximizes the yield of desired products. Therefore, our main objective was to analyze and define the main operational hydrodynamic parameters (including flow field, power consumption, mixing time, and mixing energy) and mass transfer process (in this case, gas–liquid transfer) of two different commercial bioreactors (BioFlo® 115 and BioFlo® 415). The obtained results are allowed using mathematical relationships to describe the analyzed processes that can be used to predict the mixing process and mass transfer ratio in BioFlo® bioreactors. The proposed correlations may be applied for the design of a scaled-up or scaled-down bioreactors.

Effect of ultrasonic frequency on the bacterial community structure during biofouling formation in microfiltration membrane bioreactors for wastewater treatment

Biofouling significantly reduces the performance efficiency of membrane bioreactors due to the colonization and accumulation of a matrix of microorganisms. In order to investigate the effect of ultrasonic frequency on biofilm formation and bacterial ecology at different frequencies, four microfiltration membrane modules were subjected at 0, 20, 30 and 40 kHz in pilot-scales. The results of massive parallel sequencing showed that the application of ultrasonic frequency significantly affected the bacterial population in biofouling and modifies the species richness even at low frequency. This research reveals that the application of ultrasonic frequencies avoids the colonization of Acinetobacter genus, which is considered an initial colonizer of biofouling and clogging in the submerged membrane reactor, fact that caused problems in full-scale wastewater treatment plant. The promotion of Gordonia genus was observed during the application of any ultrasounds frequencies (20,30 and 40 Hz). The compositional statistics data exposed the similarity of bacterial communities under medium-high ultrasonic frequency, while those great distances were found in both low and no-ultrasounds frequencies apply. These results suggest that the application of ultrasounds in membrane bioreactor for treating wastewater could be effective in the potential reduction of biofouling formation in order to improve the to improve the useful life of this system with short periods of application of ultrasound.

Energy Efficiency of a Small Bioreactor in Various Climatic Zones

The authors proposed a model for estimating the heat balance and energy efficiency of a bioreactor that makes possible for a small-sized reactor operating on a relatively low-energy substrate to determine the critical volume, under which the existing climatic conditions allow year-round fully autonomous operation of the digester, as well as for evaluation the potential energy efficiency of such a bioreactor (output commodity heat). For the numerical characteristics of the climatic zone, it is proposed to use the average annual temperature and/or the “degree-day of the heating period” (DDHP) indicator common in construction heat engineering; the DDHP value more adequately characterizing the unevenness of the average monthly temperature distribution, i.e. degree of climate continentality. At the same time, the value of the critical volume of the bioreactor, at which year-round autonomous operation of the digester operating on the municipal sewage sludge, is possible, varies from 7.5 (Vladikavkaz, DDHP = 3410) to 17.0 m3 (Tomsk, DDHP = 6938), i. e. increases almost in proportion to the degree-day of the heating period. It should be noted that when using a substrate with a high biogas yield, e. g., pig manure (a biogas yield of 40 g/kg is adopted), the critical volume in all cases is less than 1 m3. Such results are relevant only for relatively low-energy raw materials. The nature of changes in the output of commodity heat, depending on the volume of the bioreactor and climatic conditions, is quite expectable, viz. the amount of heat that is useful for business interests is higher, the higher is the reactor volume and the milder is the climate. However, when the reactor volume is less than 5 m3, the non-linearity of the graphs is much higher, i. e. for a designer of especially small bioreactors, it seems mandatory to carry out such calculations. The obtained numerical values can be useful both for the designer of bioreactors and for the customer of the project when evaluating the economic efficiency of the planned new innovations.

Nitrogen Removal Efficiency and Microbial Community Analysis of a High-Efficiency Honeycomb Fixed-Bed Bioreactor

Based on the concept of microbial community multi-processing in integrated spatial bacterial succession (ISBS), this study constructs a highly efficient cellular fixed-bed bioreactor that follows the growth of biological flora in the wastewater treatment process. The reactor is organically partitioned based on synergistic laws and in accordance with environmental and microbial metabolic changes, and sewage is subjected to unitized and specialized biological treatment under direct current conditions. The results show that the ISBS reactor exhibits stable nitrogen removal performance under a low-carbon source. Compared with traditional sewage biochemical treatment technology, the microbial concentration is increased by 2–3 times and even up to 12 times, and the ammonia nitrogen removal rate is maintained at 99%. The removal rate reaches 90% (hydraulic retention time of 14 h). High-throughput sequencing analysis based on 16S rDNA reveals the microbial community structure succession at different depths of the same section of the reactor. The microbial community is rich under the influence of environmental factors and exhibits different responses. The intervals vary. An analysis of the microbial community function explains why the ISBS reactor has high nitrogen removal efficiency.

Geospatial investigation of physicochemical properties and thermodynamic parameters of biomass residue for energy generation

Biomass represents vast under-explored feedstock for energy generation across the globe. Among other factors, the location from where the feedstock is harvested may affect the overall properties and the efficiency of bioreactors used in the conversion process. Herein is reported some physicochemical properties, the kinetic study and thermodynamic analysis of corn cob sourced from two major economies in sub-Sahara African region. Brunauer Emmett and Teller (BET) analysis was performed to investigate the surface characteristics of corn cob while Fourier transform infrared (FTIR) spectroscopy revealed the corresponding functional group present in the selected biomass residue. The proximate and CHNSO analyses were performed using the standard equipment and following the standard procedures, then the result is reported and compared based on the geographical locations under consideration. Also, the thermal decomposition study was carried out at different heating rates (10, 15, 30 °C min−1) in inert atmosphere while the kinetic parameters were evaluated based on Flynn–Wall–Ozawa (FWO) and Kissinger–Akahira–Sunose (KAS) methods. The analysis of variance (ANOVA) showed that there is a statistically significant difference between ultimate constituents, the fixed carbon, and volatile matter obtained from the two countries at 95% confidence level. FTIR spectroscopy showed different spectra peak in both samples which means there are varying quantity of structural elements in each feedstock. The pore surface area (1.375 m2/g) obtained for corn cob from South Africa (SC25) was greater than the value (1.074 m2/g) obtained for Nigeria (NC25). From the result, the highest value of activation energy (Ea = 190.1 kJ mol−1 and 189.9 kJ mol−1) was estimated for SC25 based on KAS and FWO methods, respectively. The result showed that the geographical location may somewhat affect some energetic properties of biomass and further provides useful information about thermodynamic and kinetic parameters which could be deployed in the simulation, optimization, and scale-up of the bioreactors for pyrolysis process.