DefinePK

Research Objective

To generate biomethane using animal blood as a substrate exposed to different pretreatments and to determine the most feasible kinetic model for biomethane production.

Methodology

The study involved collecting pure animal blood from a slaughterhouse. Biomethane potential (BMP) tests were conducted using lab-scale digesters incubated at 35°C for 77 days. Various pretreatments were applied to the animal blood: NaOH/Sonication, NaOH/Heat, Only Sonication, H2O2/Sonication, and a blank substrate. Parameters such as Total Solids (TS), Volatile Solids (VS), Fixed Solids (FS), pH, and Soluble Chemical Oxygen Demand (SCOD) were analyzed. Biogas and methane production were measured, and kinetic modeling (Zero Order, First Order, Second Order, and Chen & Hashimoto) was employed to simulate methane yield, with the coefficient of determination (R2) used to identify the best-fitting model.

Methodology Flowchart

                        graph TD
    A[Sample Collection: Animal Blood] --> B[Pretreatment];
    B -- NaOH/Sonication --> C[BMP Test Setup];
    B -- NaOH/Heat --> C;
    B -- Only Sonication --> C;
    B -- H2O2/Sonication --> C;
    B -- Blank Substrate --> C;
    C --> D[Incubation 35°C, 77 days];
    D --> E[Measurement: Biogas & Methane Production];
    E --> F[Data Analysis];
    F --> G[Kinetic Modeling];
    G -- Chen & Hashimoto Model --> H[Determine Best Fit Model];
    H --> I[Results & Conclusion];                    

Discussion

The study highlights that slaughterhouse waste, specifically animal blood, is a valuable substrate for biomethane production. Pretreatment methods significantly enhance biogas and methane yields. The pH range of 6-8 is optimal for efficient digestion. Higher SCOD levels in pretreated samples indicate a greater amount of oxidizable organic material, leading to increased methane production. NaOH/Sonication pretreatment proved most effective due to improved solubility and conversion of volatile solids into methane.

Key Findings

NaOH/Sonication pretreatment resulted in the highest percentage of methane production (86%), followed by NaOH/Heat (85%), Only Sonication (83%), H2O2/Sonication (82%), and the blank substrate (76%). The Chen and Hashimoto model was found to be the most feasible kinetic model for this study, with R2 values ranging from 0.982 to 0.992.

Conclusion

Anaerobic digestion is an effective technology for utilizing abattoir waste like animal blood for economic benefit and bioenergy production. NaOH/Sonication pretreatment is the most efficient method for maximizing biomethane production from animal blood. The Chen and Hashimoto kinetic model accurately predicts the performance of the experimental design. Co-digestion with other waste types and optimization of pretreatment parameters could further enhance methane production.

Fact Check

1. Methane Production Percentage: NaOH/Sonication pretreatment achieved the highest methane production at 86%.
2. Incubation Time: BMP bottles were incubated for 77 days.
3. Kinetic Model Fit: The Chen and Hashimoto model showed excellent fitting to the experimental data with R2 values between 0.982 and 0.992.

Mind Map