Crude oil contamination in soil, particularly in ecologically sensitive regions like Nigeria’s Niger Delta, presents a persistent environmental challenge. Bioremediation, which uses microorganisms to break down hydrocarbon compounds, offers a promising cleanup solution. Enhancing this process with biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More, a carbon-rich substance from biomassBiomass is a complex biological organic or non-organic solid product derived from living or recently living organism and available naturally. Various types of wastes such as animal manure, waste paper, sludge and many industrial wastes are also treated as biomass because like natural biomass these More, has shown great potential. However, effectively predicting the total petroleum hydrocarbon (TPH) levels during biochar-enhanced bioremediation has been challenging due to the complex interactions between biochar, microbial activity, and environmental factors.

A recent study published as a Journal Pre-proof in Soft Computing Letters by Daniel Hogan Itam, Ekweme Chimeme Martin, and Ibiba Taiwo Horsfall addresses this gap. The researchers employed an innovative approach: an artificial ecological system-based optimization (AEO) model, to forecast the maximal TPH removal from crude oil-polluted soil treated with a biochar mix. This model integrates artificial intelligence algorithms with ecological principles to simulate and optimize the TPH removal process.

The AEO model predicted a maximum TPH removal of 87.76% with an exceptionally fast convergence time of 0.02 seconds at 20 iterations. When compared to other cutting-edge optimization methods like Particle Swarm Optimization (PSO), Social Spider Optimization (SSBO), and Ant Colony Optimization (ASO), the AEO demonstrated superior optimization efficiency, convergence rate, and computational effort, especially for real-world engineering problems. This evaluation was performed at different upper boundaries of biochar components, specifically (15g, 10g, 3g) and (15g, 12g, 3g) for poultry litter (PL), rice straw (RS), and pine wood (PW) biochar, respectively. The AEO consistently computed faster than its counterparts in both scenarios.

The study also delved into the effectiveness of the biochar mix itself. The contaminated soil from Kpuite, Ogoni, in Nigeria’s Niger Delta, initially had a low pHpH is a measure of how acidic or alkaline a substance is. A pH of 7 is neutral, while lower pH values indicate acidity and higher values indicate alkalinity. Biochars are normally alkaline and can influence soil pH, often increasing it, which can be beneficial More of 4.72, a temperature of 28.5∘C, and a moisture content of 21.49%. While total heterotrophic bacteria (THB) and hydrocarbon-utilizing bacteria (HUB) counts were promising at 5.80×103 cfu/g and 5.70×102 cfu/g respectively, indicating potential for bioremediation if stimulated, hydrocarbon-utilizing fungi (HUF) were lower. The biochar mix comprised pine wood (PW), rice straw (RS), and poultry litter (PL) biochars. Notably, RS and PL biochars had alkaline pH values (8.23 and 7.16 respectively), making them more suitable for bioremediation as they can help neutralize the acidic soil. Pine wood biochar, however, had a lower pH of 3.60.

The interaction effects between the different biochar types were crucial. Increasing the amount of poultry litter (PL) biochar significantly enhanced TPH degradation, particularly when combined with rice straw (RS) and pine wood (PW) biochars. Low levels of PL biochar (5g) showed negligible TPH elimination and minimal interaction between RS and PW biochars. However, increasing PL biochar to 10g led to moderate TPH degradation due to a larger synergistic action, with the highest removal efficiency (nearly 50%) observed at 15g PL biochar. This suggests that PL biochar improves the bioavailability and efficacy of RS and PW biochars, making their interaction critical for optimal TPH degradation.

This research holds significant environmental implications. By accurately predicting TPH levels, environmental scientists and engineers can design more effective bioremediation strategies, monitor progress, and ensure successful cleanup of contaminated sites. The use of biochar, derived from organic waste, also promotes sustainability by repurposing waste materials and reducing the need for synthetic chemicals. While the study’s results are promising, future research will focus on validating the AEO technique in real-world scenarios, exploring long-term effects on soil properties, and investigating additional factors like oxygen availability and nutrient supplementation to further optimize bioremediation processes.

Source: Itam, D. H., Martin, E. C., & Horsfall, I. T. (2025). An artificial ecological system-based optimization to forecast the maximal TPH removal from Nigeria’s Niger Delta crude oil-contaminated soil treated with a mix of biochar. Soft Computing Letters.