Lipid production from palm oil mill effluent by microalgae

In tropical countries, the palm oil industry discharges a large amount of wastewater. The wastewater can serve as an economical nutrient source or substrate that can support the cultivation of microalgae. This study aimed to identify the local species of microalgae potentially existing in the industrial wastewater of palm oil mill effluent (POME). POME was selected as the key source of waste due to its higher potential in producing lipids from microalgae as biofuel substrate. A novel green microalgal strain was isolated from POME of Kulai-Johor west Palm Oil Mill in Malaysia and was identified as Chlamydomonas sp. and subsequently named Chlamydomonas sp. UTM 98 with Catalogue No. of KR349061. This strain was cultivated in media with different volume ratios of POME and Basal Bald Medium (BBM). Lipid is generally a group of organic compound that serves as the primary raw material for biofuel. Therefore, this study emphasizes the effectiveness of POME as the main carbon source to maintain the growth of microalgae and simultaneously to increase the lipid content. In addition, glucose (C6H12O6) was also used to compare the effectiveness of their cultivations against POME. Furthermore, four selected strains of green microalgae are applied namely Chlorella vulgaris, Chlorella pyrenoidosa, Chlorella sorokiniana, Tetraselmis sp and isolated microalgae from POME. All cultivation of microalgae were initially carried out in 250mL Erlenmeyer flask containing 100 mL medium at ± 30oC with continuous illumination (± 14 µmol-1 m-2 s-1) and up to 20 days of cultivations. The study demonstrated that Chlamydomona incerta (C. incerta) is the predominant species for specific growth rate (µ), biomass productivity and lipid content in the diluted POME with the value of 0.099/d, 8.0 mg L-1.d, 2.68 mg lipid mg-1 Cell Dry Weight (CDW), respectively. However, C. incerta showed that there was about one and the half times more lipid productivity when the biomass cells utilized glucose as carbon source, compared to POME. The best condition was determined with various carbon-to-total nitrogen (C:TN) ratio and light/dark (L:D) cycles, respectively. As a result, the highest lipid content was achieved when the condition was controlled at C:TN (100:7) and with continuous light (24 hr) which recorded a value of 17 mg lipid mg-1 CDW. These results concluded that C. incerta had the highest growth rates and lipid production in the diluted POME compared to other strains of microalgae. Finally, the study suggested several improvement of the experiment to achieve higher lipid production at steady state condition by manipulating the ratio of carbon-to-total nitrogen and the light intensity on the bio-substrate. The Nile Red method was used to measure the lipid content in the culture. Fatty Acid Methyl Esters (FAMEs) and samples were analyzed via gas chromatography. POME with COD 250mg L-1 concentration showed the greater lipid content with absorbance 3.138a.u. The result showed that Chlamydomonas sp UTM 98 grown in the media of diluted POME exhibited a high potential of microalgae for biomass production and POME nutrients removal

Bioenergy production and nutrients removal by green microalgae with cultivation from agro-wastewater palm oil mill effluent (POME) - A review

Environmental pollution specifically wastewater is gaining attention both in the developed and developing countries. Malaysia is considered as one of the major palm oil producers in the world. Therefore, it is important to develop an environmental friendly and economic method to treat palm oil mill effluent (POME). The wastewater can serve as an economical nutrient source or substrate that can support the cultivation of microalgae. This can be a great nutrient for algal cultivation at the same time as remediating effluent and generating biomass. Nowadays, many microalgae species are being investigated to determine their potential and effectiveness for phytoremediation application, especially high growth rate. However, using synthetic media for growing microalgae in a mass scale is costly. It is acknowledged that POME (as nutrients enriched media) assisted enhanced microalgae growth under certain condition can considerably reduce the presence of organic and inorganic compounds. In this review, the potential of wide range of the predominant microalgae species with main focus on green microalgae (high removal efficiency): Chlamydomonas sp and Chlorella sp were investigated. Moreover, we discussed about the history, methods and future prospects in nutrients removal by green microalgae comprehensively. This review discusses several potential strategies for tackling the environmental issue generated by agro-waste water POME with enhancement of biomass productivity which can be used as an alternative for energy production

Safety analysis of ammonia exposure at a chemical plant

The Environmental Protection Agency (EPA) is issuing this Alert as part of its ongoing effort to protect human health and the environment by preventing chemical accidents. In chemical manufacturing industry, there are many hazards in the workplace particularly chemical hazard. Although there is safe work procedure for activities involving chemical handling, however, incidents of ammonia exposure are still occuring. Therefore, assessment on the workplace conditions and the knowledge and attitude of employees is essential to evaluate the extent of the problem. Accordingly, the objectives of this study are to (1) identify potential exposures, possible effects and root causes of ammonia exposure to workers, (2) to analyse knowledge and attitude of workers on ammonia exposure, and (3) to propose recommendations (guideline) for the improvement of safety handling of ammonia. A Job Safety Analysis was conducted to identify potential exposures, possible effects and root causes of ammonia exposure to workers. Knowledge and attitude questionnaire was conducted for 36 production workers of a company to analyse their knowledge and attitude on ammonia exposure. The results show that the potential ammonia exposures were from this areas; improper carboy cap fastening and lid absence, transfer spillage, residuals splashes, overcharging and continuous pumping, hose leakage, loose and dismantled, rushed scooping, manhole exposure, and charge-in pump not halted. The possible effects of ammonia exposures are carboy leaked, overspill, hose leaked, forced out through loosened hose, ammonia evaporated to fumes, ammonia fumes inhaled into respiratory system, sprinkles and splashes, and direct contact with skin and eyes. The root causes of ammonia exposures are; no initial checking, not wearing PPE, improper pouring method, mixing tank unattended, procedure overlooked, rushing, not following proper procedure, and pump control unattended. The workers’ knowledge of ammonia exposure was high, whereas their attitude was moderate. A guideline was proposed to improve safety handling of ammonia and enhance the knowledge and attitude of workers

Evaluation of awareness and safety among students and technicians in UTM research chemical laboratories

Incidences in chemical research laboratories have been occurring at an alarming rate resulting in chemical-related injuries and illnesses ranging from skin and eye irritation to burns, chronic diseases, or death. Students need to make safety as part of their daily routine when working in chemical research laboratories by understanding particular hazardous characteristics of chemicals they are using in order to prevent accidents. Standards such as OSHA’s Occupational Exposure to Hazardous Chemicals in Laboratory standard (29 CFR 1910.1450) can be used by institutions for safe work in research laboratories. The purpose of this study is to assess the awareness and safety of students and technicians in Universiti Teknologi Malaysia (UTM) chemical research laboratories, to identify the type of hazards in chemical research laboratories and propose improvements to existing guidelines. For this study, a qualitative method was used for data collection using a self-administered questionnaire for students and technicians and laboratory checklist. The data collected was analysed using Statistical Package for Social Sciences (SPPS). After various observations and analysis, it is recommended that chemical spillage and handling should be included in the existing guidelines for awareness and safety on hazards caused by chemical and acutement substances in the chemical research laboratories; students should be given safety practices training to create awareness and prevent laboratory accidents when carrying out experiments; and laboratory inspections should be carried out to see whether the students and technicians are adhering to laboratory rules and regulations

Palm Oil Mill Effluent as an Environmental Pollutant

In recent decades, Malaysia has been known as one of the world’s leading producers and exporters of palm oil products. Every year, the number of palm oil mills increases rapidly, thus increasing the capacity of fresh fruit bunch waste or effluent discharge. Based on the data from the Malaysian Palm Oil Board in 2012, Malaysia produced 99.85 million tons of fresh fruit bunch (FFB) per year. However, about 5–5.7 tons of water was required in order to sterilize the palm fruit bunches and clarify the extracted oil to produce 1 ton of crude palm oil resulting in 50% of the water turning into palm oil mill effluent (POME). POME is one of the major environmental pollutants in Malaysia. The characteristics of POME and its behavior, if discharged directly, in water are described in this chapter. The suspended solid and nutrient content in POME could be able to support the growth of algae. This chapter aims to demonstrate that POME could be used as a main source for algae production, and this effluent is one of the main environmental problems in the tropical region especially in Malaysia

A review on microalgae as potential lipid container with wastewater treating functions

Abstract Microalgae are reported as potential source to produce lipids from their biomass cells. Lipid as a group of organic compound is a primary raw material used in biofuel production as well as component for foods, cosmetic products, fertilizers and animal feed. As the resources of manufacturing lipid from synthetic media are costly, the derivation of inexpensive carbon and nutritional sources from wastewater such as palm oil mill effluent (POME) is useful in massive scale. Furthermore, unique characteristic of microalgae as alternative agents to treat POME wastewater is another encouraging aspect of its application. In addition, biodiesel production from algae can produce 5,000 -15,000 gallons of biodiesel per acre/year. However, high yield production of high-lipid-content-algae biomass, determination of effective techniques in order to harvest grown algae, algal oil extraction and trans-esterification of extracted oil for converting into biodiesel are challenging issues need deep investigation. This review is focused on previous studies on POME as possible carbon and nutritional source used to treat environmental pollution caused by POME discharges and to increase the growth rate of microalgae in order to high-lipid content production

Recent advances in process improvement of dark fermentative hydrogen production through metabolic engineering strategies

Biological means of hydrogen (H2) production has attracted tremendous research and development attention. Dark fermentation provides a possible way of producing H2 from a range of renewable energy sources, including wastewater. During fermentation, various metabolites are formed to create a complex metabolic flux network. Insufficient focus has been placed on the metabolic engineering that is intrinsic to fermentation. This current review summarizes the biochemical pathways occurring in the metabolic network of dark fermentation and how the key operational factors influence metabolism during dark fermentation. Recent developments and strategies for metabolic engineering that have been described to enhance H2 production are recommended. Finally, the economic analysis related to bio-H2 production and prospects is examined. It is envisaged that this study can give beneficial aspects in terms of fundamental knowledge, understanding, and the latest technology for scientists and research engineers in the field of bio-based H2 generation

The effects of caffeine, gliclazide, and prazosin on the performance and microbial diversity in an up-flow anaerobic sludge blanket (UASB) reactor

A laboratory-scale up-flow anaerobic sludge blanket (UASB) reactor was deployed in this study to examine the relationship between pharmaceutical compounds and anaerobic process performance. The reactor successfully biotransformed up to 87–99% of psychostimulant caffeine, anti-diabetic drug gliclazide, and anti-hypertensive drug prazosin during 92 days of operation. At the same time, fluctuations were recorded for the methane gas production, and also the domination of acetic acid and propionic acid in the presence of pharmaceutical compounds was measured. The results from 16s rRNA sequencing revealed that these compounds stimulated the growth of hydrogenotrophic methanogens, mainly Methanobrevibacter and Methanobacterium, while shifting the compositions of hydrolytic and fermentative bacteria. These outcomes proved the capability of the pharmaceutical compounds to influence the process performance by changing the microbial compositions in the anaerobic reactor

Characterisation of synthesised trimetallic nanoparticles and its influence on anaerobic digestion of palm oil mill effluent

The augmentation of biogas production can be achieved by incorporating metallic nanoparticles as additives within anaerobic digestion. The objective of this current study is to examine the synthesis of Fe–Ni–Zn and Fe–Co–Zn trimetallic nanoparticles using the co-precipitation technique and assess its impact on anaerobic digestion using palm oil mill effluent (POME) as carbon source. The structural morphology and size of the synthesised trimetallic nanoparticles were analysed using a range of characterization techniques, such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), and Energy-dispersive X-ray spectroscopy (EDX). The average size of Fe–Ni–Zn and Fe–Co–Zn were 19–25.5 nm and 19.1–30.5 nm respectively. Further, investigation focused on examining the diverse concentrations of trimetallic nanoparticles, ranging from 0 to 50 mgL−1. The biogas production increased by 55.55% and 60.11% with Fe–Ni–Zn and Fe–Co–Zn trimetallic nanoparticles at 40 mgL−1 and 20 mgL−1, respectively. Moreover, the lowest biogas of 11.11% and 38.11% were found with 10 mgL-1 of Fe–Ni–Zn and Fe–Co–Zn trimetallic nanoparticles. The findings of this study indicated that the trimetallic nanoparticles exhibited interactions with anaerobes, thereby enhancing the degradation process of palm oil mill effluent (POME) and biogas production. The study underscores the potential efficacy of trimetallic nanoparticles as a viable supplement for the promotion of sustainable biogas generation

Efficiency of Microalgae Chlamydomonas on the Removal of Pollutants from Palm Oil Mill Effluent (POME)

AbstractMalaysia is considered as a major palm oil producer in the world. Therefore, it is vital to utilize an environmentally friendly and inexpensive method to treat palm oil mill effluent (POME) in Malaysia. Nowadays, the use of microalgae to remove pollutants from POME has gained a lot of attention. The main objective of this research was to investigate the effect of POME as a nutrient on the microalgae growth and analyze the removal rate of pollution. In this study, a pure culture Chlamydomonas incerta was aseptically transferred to an Erlenmeyer flask containing POME. The effect of POME as a high nutritional substrate, different cultivation scales, carbon total nitrogen (C:TN) ratio, and the lipid productivity of microalgae C. incerta were assessed. C. incerta was grown at room temperature under continuous illumination with the intensity of ± 15 (μmol/m2/s) for 28 days, followed by the measurement of chemical oxygen demand (COD) reduction at different substrate concentrations. The results of this study demonstrated that organic carbon was removed by C. incerta for the ratio of 100:7, 100:13, and 100:31 respectively within the second day of cultivation. Fast growth of microalgae was observed in organic and inorganic substrates for adoption within the second day of experiment. The optimum achievement rate of nutrient removal with C. incerta was about 67.35% of COD for 250mg/L of POME concentrations in 28 days. The significance of this study is regarding the introduction of a new microalgae strain with a high ability to remove nutrients from POME, which can contribute to the effort in finding an efficient and economic technology for improving our environment