Performance Analysis of Anaerobic Digestion of Textile Dyeing Industry Effluent in a Modified Sequential Batch Reactor

The effects of four types of sulfonamide antibiotics (SAs), including sulfaquinoxaline, sulfamethoxazole, sulfamethoxydiazine and sulfathiazole, on the digestion performance during anaerobic digestion process were studied using a lab-scale anaerobic sequencing batch reactor, and the changes of the community structure in the presence of SAs were investigated with the help of high throughput sequencing. The results indicated that when SAs were added, the hydrolytic acidification process was inhibited, and the accumulation of volatile fatty acids (VFAs) was induced, resulting in the suppression of methane production. However, the inhibition mechanism of different SAs was quite different. The inhibitory effect of high concentration of SAs on the hydrolysis of solid particulate matter into dissolved organic matter followed the order of sulfaquinoxaline > sulfamethoxydiazine > sulfathiazole > sulfamethoxazole. SAs have obvious inhibitory effects on acidification and methanation of dissolved organic matter, especially sulfathiazole. The richness and the community composition of the microorganism including bacteria and archaea in the digestion system were affected by SAs. Under the effect of SAs, the relative abundance of many microorganisms is negatively correlated with methane production, among which Methanobrevibacter, a kind of Archaea, had the greatest influence on methane production.

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Anaerobic Digestion Process for the Treatment of Sisdole Landfill Leachate in Nepal

Journal of Southwest Jiaotong University ◽

10.35741/issn.0258-2724.55.4.35 ◽

2020 ◽

Vol 55 (4) ◽

Author(s):

Bikash Adhikari ◽

Shilpa Koirala

Keyword(s):

Anaerobic Digestion ◽

Removal Efficiency ◽

Landfill Leachate ◽

Waste Treatment ◽

Batch Reactor ◽

Batch Reactors ◽

Leachate Treatment ◽

Anaerobic Digestion Process ◽

Digestion Process ◽

Solids Concentration

Along with the population, organic waste has been rising significantly in recent years. The resulting uncontrollable waste loads and conventional methods of waste treatment have begun to cause chaos at the landfill sites. This study evaluates the performance of an anaerobic digestion process using batch reactors for the treatment of landfill leachate collected from the Sisdole landfill site in Nuwakot, Nepal. A lab-scale anaerobic batch reactor was set up in Kathmandu University, Nepal. Using an anaerobic digestion process, COD values of the leachate decreased from 2230 mg/l to 1125 mg/l (removal efficiency of ~50%), whereas total solids concentration decreased from 1925 to 925 mg/L under a retention time of 10 days. In addition, Monod’s model was established to design an Anaerobic Sequential Batch Reactor to achieve better performance, resulting in 85% removal efficiency for the leachate treatment. Overall, this study analyzed the anaerobic digestion process on the landfill leachate of Sisdole, and modeled the process to identify the conditions required for increasing the efficiency of treatment of Sisdole landfill leachate.

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Performance Analysis of Three Controllers for the Polymerisation of Styrene in a Batch Reactor

Chemical Product and Process Modeling ◽

10.2202/1934-2659.1014 ◽

2007 ◽

Vol 2 (1) ◽

Cited By ~ 2

Author(s):

Emmanuel E Ekpo ◽

Iqbal M Mujtaba

Keyword(s):

Performance Analysis ◽

Batch Reactor ◽

Monomer Conversion ◽

Average Chain Length ◽

Generic Model ◽

Batch Reactors ◽

Dynamic Optimisation ◽

Model Control ◽

Simple Kinetic Model ◽

Generic Model Control

The performance analysis of three advanced non linear controllers is the main focus of this paper. All three controllers are applied for the control of a batch polymerisation reactor which is defined by a very simple kinetic model for the polymerisation of styrene. This simple set of equations describing the polymerisation process is first solved using the sequential strategy i.e. Control Vector Parameterisation (CVP) technique within gPROMS to find optimal initial initiator concentrations and the reactor temperature trajectory necessary to yield desired polymer molecular properties (defined here as fixed values of monomer conversion and number average chain length) in minimum time. The sequential solution strategy has had limited application in solving optimisation problems for polymerisation in batch reactors, most researchers instead employing the Pontryagin's Maximum Principle (PMP) to solve optimal control problems involving these systems.The temperature trajectory obtained from the dynamic optimisation is used as the setpoint to be tracked by the three controllers: Dual Mode control with PID, which is representative of industrial practice, Generic Model Control (GMC) with Neural Networks as online heat release estimator, and Direct Inverse Control (DIC). Published work on the last two controllers as applied to the control of a batch polymerisation reactor is absent from the literature.When the performances of the different controllers are evaluated, it is seen that the GMC-NN controller performs better than the other two for the system under consideration.

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