8 research outputs found
Optimization of process parameters for the production of citric acid using sewage sludge as major fermentation media
No full textA research was conducted on liquid state bioconversion for the production of citric acid using sewage treatment plant (STP) sludge as the main substrate with supplementation of sucrose as co-substrate. Three parameters were examined to determine the best process optimization conducted in two liter (2L) bioreactor. Two level factorial designs with three parameters were applied for the fermentation. It was
carried out using local isolates of Aspergillus niger strain O103A at room temperature (30 to 32°C),agitation was set at three different values which are 100, 200 and 300 rpm. Initial pH for fermentation was set at 5 and it was further adjusted to three levels which are 2, 3 and 4 on the second day of the fermentation. Another parameter was aeration where 1, 1.5 and 2 vvm were introduced. The fermentation was carried out for five days. The maximum yield of citric acid obtained throughout the fermentation was 23.68 g/L, which is due to low pH, low agitation and high aeration values
Sewage sludge as an alternative resource: Optimization of media for citric acid production
No full textSewage is the largest contributor of organic pollution to water resources as well as to
surrounding environments all over the world. In Malaysia, its contribution is top listed (64.4%),
followed by animal husbandry wastes (32.6%), agro-based (1.7%) and industrial effluent (1.3%)
in terms of the BOD load (Alam et al. 2009). Approximately 4.2 million cubic meters of sewage
sludge (pure organic waste without mixing with the industrial waste) is produced annually by
Indah Water Konsortium (IWK), a national sewerage company in Malaysia and the total cost of
managing is estimated at RM 1 billion (Kadir and Velayutham, 1999). The country has to adopt
a practical, economic, and acceptable approach in managing and disposing sewage sludge.
Present practice is either to co-dispose it with solid waste at landfill sites or direct disposal in
shallow trenches (Zain et al., 2001). However, the safe and environmental-friendly disposal of
this huge quantity of sludge is the main concern of IWK. Sludge can be a very good source of
carbon, nitrogen, phosphorus and other nutrients for many microbial processes. Therefore, the
production of citric acid using sewage sludge as the sole media would be an alternative to
overcome sludge disposal problem as well as to fulfill the demand of this organic acid globall
Process optimization in citric acid production using sewage sludge as fermentation media
No full textA research has been conducted on liquid state bioconversion for the production of citric acid using Sewage Treatment Plant (STP) sludge as main substrate and added with sucrose as co-substrate. Three parameters were examined as to determine the best process optimization conducted in two liter (2L) bioreactor. Two level factorial designs with three parameters are applied for the fermentation. It was carried out using local isolates Aspergillus niger strain O103A at room temperature (30-32oC), agitation is set at three different values which are 100, 200 and 300rpm. Initial pH for fermentation is set at 5 and it was further adjusted to three levels which are 2, 3, and 4 on the second day of the fermentation. Another parameter is aeration where 1, 1.5 and 2 vvm were introduced. The fermentation was carried out for five days. The maximum yield of citric acid obtained throughout the fermentation is 23.68 g/L, which is due to low pH, low agitation and high aeration values
Sewage Sludge as a Renewable Resource for Citric Acid Production: Optimization of Supplementary Nutrients
No full textThe optimization of supplementary nutrients in the sewage sludge as a basal medium was carried out to determine the media components on the citric acid production. Two statistical designs were employed in the citric acid productions which are Plackett-Burman and central composite design (CCD). For the media screening, the two-level Plackett-Burman was applied. Under the experimental conditions, it was observed that total suspended solids of sewage sludge (TSS), sugar, cassava, methanol, potassium di-hydrogen phosphate and urea to be the major factors in maximizing citric acid production. A study of single factor was conducted to find the optimum ranges of parameters for citric acid production followed by the central composite design (CCD) under the responses surface methodology. A polynomial model was created to correlate the relationship between two factors (sewage sludge TSS and sugar) and citric acid production. The optimum yield of citric acid, 29.12 g/L was produced with 0.8% TSS sewage sludge and 7% sugar in four days of fermentation. The determination of coefficient (R2) from the analysis was 0.9527, indicating that the model of this experiment is significant
Harvesting solutions: discover the evolution of agriculture wastewater treatment through comprehensive bibliometric analysis using Scopus database 1971-2023
No full textThis bibliometric study examines scholarly research on agricultural wastewater treatment using Scopus data from 1971 to 2023 by exploring publication trends, leading countries, prolific authors, and keyword co-occurrences. This study was conducted using VOSviewer software (version 1.6.17) which enables advanced bibliometric analysis and visualization, exploring the publication networks and patterns. By using various procedures to collect and refine data, 1908 research articles were retrieved. The findings indicate a steady growth in research on wastewater treatment since the 1970 s, with a significant surge in publications in recent decades. Research on wastewater treatment for agriculture has significantly increased, particularly focusing on technologies, reuse in agriculture, and environmental impacts. However, several research gaps to be addressed, including specific focus areas within agriculture wastewater treatment, underrepresented regions in the literature, interdisciplinary approaches, long-term environmental impacts, and policy effectiveness and implementation. The analysis also highlights influential authors, institutions, and countries driving research in this field, along with the most cited publications and journals. Additionally, the study identifies research gaps and suggests future research directions in wastewater treatment. Overall, this bibliometric analysis provides valuable insights into the landscape of wastewater treatment research, its evolution over the past five decades, and its economic and policy implications. © 2024 The Author
Optimization of biodiesel production by solid acid catalyst derived from coconut shell via response surface methodology
No full textAn Assessment of the Potential, Suitability and Sustainability of the Sand Mining Site in the Kemaman River Basin, Terengganu Using Acoustic Doppler Current Profiler
No full textSand mining from the catchment basin for building is a worldwide issue. The increasing demand for sand in the construction industry has led sand suppliers to look for alternative methods by which they can obtain source of sand from the riverbed. Floodplain and river slabs can be used as new sources of sand mining. In Sungai Kemaman, during September until March a high precipitation can cause high flow in river. This high flow can cause riverbank erosion which leads to instability of river. Therefore, river erosion can probably be reduced by identifying the potential area for sand mining. This research was conducted to analyse sand capability on floodplain and riverbed by integrating resistivity method and sediment transport loads using Acoustic Doppler Current Profiler (ADCP). Resistivity survey is used in determining the availability of potential soil at the study area and the equipment could measure subsurface profile up to 80 meters depth. Meanwhile, ADCP survey is utilized to make river profiler in term of velocity meshes and riverbed depth. The primary data collected was from 20 January 2014 to 19 February 2014. The findings found that the samples trapped in the Helly-Smith grabber were majority of the samples consisted more than 93% of gravel and sand materials and from the resistivity analysis, it is verified that the surrounding materials along the Sungai Kemaman is sandy material and high potential of the sand mining site
Lake UniSZA Water Quality Monitoring: Pollution Effects to The Aquatic Environment
No full textLake is one of the complete ecosystems and source of freshwater itself. Lake serves as a habitat for aquatic plants and animals, including the microorganisms. Lake can either be formed naturally or manmade. Most formed lakes are from volcanic eruptions, or cave ruins and lakes are formed from the rainwater. Man-made lakes usually formed after mining activities, and many can be found all over the world. Water pollution, including lake pollution, is common worldwide. It can be from point-source or non-point source. Natural environmental factors can also contribute to the lake pollution. In this study, aquatic life has been found dead and the samples of both water and aquatic life were taken for analysis. Two types of analysis were conducted; in-situ sampling analysis with YSI handheld parameter and an ICP-OES analysis were conducted. The analysis shown that early low concentration of dissolved oxygen (DO) (3.5~4.5 mg/L) and highest concentration of ammoniacal nitrogen (NH4-N) (20.69 mg/L) as well as high concentration of sulphur (S) 3.506 mg/L) were found in both water sample and the tissue samples of the organisms. This concludes that the death of the aquatic life was due to the toxicity of sulphur found in the tissue samples
