Lawrence Darkwah

Kwame Nkrumah University Of Science and Technology | KNUST · Department of Chemical Engineering

Sulphur content is one of the most important fuel parameters affecting exhaust emissions from vehicles. Sulphur is a direct pollutant that can combine with other atmospheric elements to form compounds that contribute to global warming; hence minimising its quantity in fuels is essential. Standards have been set globally to regulate the sulphur cont...

Diesel is an essential energy source in the transportation and industrial sectors worldwide; hence, the quality of this commodity is crucial. This study compares various fuel samples to understand the quality of the fuels in terms of sulphur content, density, surface tension, viscosity, and calorific value. The properties of diesel fuel samples fro...

Food waste can be converted to a useful product such as biochar as a way of recycling waste to retain nutrients in the soil, which in turn contributes to carbon sequestration and offset some greenhouse gas emissions in the struggle to achieve carbon neutrality. Mixed food waste-derived biochars (FWB1–300°C, FWB2–450°C and FWB3–600°C) were pyrolysed...

In order to expand the output of solar power systems for efficient integration into the national grid, solar energy resource assessment at site is required. A major impediment however, is the widespread scarcity of radiometric measurements, which can be augmented by satellite observation. This paper assessed the suitability of satellite-based solar...

The potential of methane yield depends on the composition of feedstock which is characterized by a diversity of biodegradable fractions. This study aims at constructing and using the novel kinetic model as a tool to predict methane-to-carbon dioxide ratio from slaughterhouse solid waste using hydraulic retention time and temperature as parameters....

The drive for a sustainable society and a circular economy has motivated researchers around the globe to turn to the transformation of renewable raw materials like biomass into value-added products that are akin or superior to their fossil counterparts. Among these biomass raw materials, cocoa pod husks (CPH) which is the non-edible portion of coco...

This paper highlights some of the commonly used bio-based materials studied for their applicability as adsorbents in wastewater treatment. Additionally, few processing techniques employed to enhance the ability and or affinity of the adsorbents for wastewater treatment have been discussed. More so, some of the commonly used characterization techniq...

In order to expand the output of solar power systems for efficient integration into the national grid, solar energy resource assessment at site is required. A major impediment however, is the widespread scarcity of radiometric measurements, which can be augmented by satellite observation. This paper assessed the suitability of satellite-based solar...

Slaughterhouse activities generate large volumes of biodegradable organic wastes such as animal faeces, blood, fat, animal trimmings, paunch contents and urine. These wastes are mainly responsible for air, soil, and water pollution if untreated or poorly managed. In many developing countries, the common method adopted by most slaughterhouses in the...

Continuous expansion of agriculture for the production of biofuels may be considered a potential source of greenhouse gas (GHG) emissions due to the ever-increasing amount of waste and fossil fuel-dependent materials involved. Agricultural waste utilization through the circular bioeconomy concept offers a pathway to reduce GHG emissions. Palm oil p...

The use of macrophytes has been identified as one of the eco-friendly means of remediating soils contaminated with heavy metal(loid)s. This study sought to ascertain the synergistic influences of Hg, As, Cd and Pb on the uptake capacity of Typha capensis in remediating soils contaminated with these pollutants. Uptake of Hg, As, Cd and Pb by this aq...

The Sustainable Development Goals (SDGs) are emphatic on the role of energy for development, with a target to ensure universal access to affordable, reliable and modern energy services to about 1.3 billion people without electricity access, and to increase substantially the share of renewable energy in the global energy mix. For remote rural commun...

This study is to design a novel septic tank, named Anaerobic Upflow Domestic Septic Tank (AUDST) to recover biogas asenergy and treat domestic sewage. The green technology proposes alternate options to existing Domestic Septic Tanks (DST),encourages anaerobically pre-treatment to reduce bacteria, pollutants, Total Suspended Solids (TSS), Chemical o...

In Ghana, Biogas Technology has been limited mostly to donor-funded projects in communal areas, educational and health institutions. This has made development of biogas technology relatively minimal. In most cases, some of these projects have been abandoned due to lack of sustained funding, poor maintenance and proper management of the facilities....

Hydrocarbon-contaminated drill mud waste associated with oil and gas activities constitutes a major risk to the environment, but current conventional treatment methods have not been effective. In this study, the remedial potential of nutrients addition to stimulate the growth of microbes was harnessed to treat drill-mud waste contaminated with hydr...

The potential for using blast furnace slag (BFS) to remove heavy metals (Fe, Cu, Zn & Mn) from acid mine drainage (AMD) and restoring alkalinity explored at the laboratory scale is reported in this paper. Initial pH effects on adsorption have been studied in the pH range 2.5 – 4.5. The effect of reaction temperature on removal kinetics of single me...

Cyanide is used for gold recovery by the major gold mining companies in Ghana. Speculation on the use of cyanide and the disposal of its residual and by-products have instilled fear in local communities, the public, and sometimes employees working in the gold mining industry. A life cycle assessment (LCA) of cyanide in Ghana was conducted using Ori...

This study analyses technical potential and ex ante socioeconomic impacts of biogas production using cassava waste from agroprocessing plants. An analysis was performed for two biodigesters in two cassava processing communities in Ghana. The results showed that the two communities generate an excess of 4,500 tonnes of cassava peels per year. Using...

This study is to design a novel septic tank, named Anaerobic Upflow Domestic Septic Tank (AUDST) to recover biogas as energy and treat domestic sewage. The green technology proposes alternate options to existing Domestic Septic Tanks (DST), encourages anaerobically pre-treatment to reduce bacteria, pollutants, Total Suspended Solids (TSS), Chemical...

Electricity access is key in driving socio economic development. Since Ghana initiated its National Electrification Scheme (NES) 20 years ago, access has risen to 72%, with over 88,000 communities yet to be electrified. From 2006 to 2008, the Multifunctional Platform (MFP) programme provided mechanical energy services based on diesel engines in 38...

The quantity and quality of input and output water at the various stages of mining is of critical importance in monitoring the dynamics of mine water. This study was undertaken to assess the quantity and physic-chemical quality of water sources for ore processing, the process water pond and surface waters in the Central African Gold (CAG) Mine conc...

The research is aimed at assessing the performance of the wastewater (excluding sewage) treatment plant in a Ghanaian beverage industry. Sixteen (16) water quality parameters were analyzed by collecting influent and effluent wastewater samples of the treatment plant for a year and their average values were compared with EPA (Ghana) guidelines for b...

The study aimed at conducting a water quantity audit in a Ghanaian beverage plant. Primary data on the daily volumes of input water from the main reservoirs of the plant, daily volumes of beverage produced and the water consumed at the 8 metered stages of the plant out of a total of 12 stages were recorded over a period of four months. Secondary da...

Background Petroleum fuel is facing acute peaking problems due to the ever increasing demand in the face of dwindling production rate and the instabilities in the centres of petroleum production, both resulting in fluctuations in crude oil price which affects national and global economies. These factors, among others, have renewed the interest i...

Real acidic mine-water drainage was seeded with Acidithiobacillus ferrooxidans to catalyse the removal of iron contained therein. The addition of At. ferrooxidans increased metal precipitation kinetics and decreased the water iron content by approximately 70%. Supplementing non-sterile mine water with a bacterial growth medium accelerated metal rem...