Palm Oil Mill Effluent Sludge Research Articles

Rhamnolipids production by Pseudomonas aeruginosa RW9 using palm oil mill effluent sludge oil as a carbon source

The production of biosurfactants has garnered considerable attention in recent years due to their unique properties, which include the ability to enhance oil solubility in water, reduce surface tension, and exhibit low environmental toxicity. In this study, we investigated the production of biosurfactants by Pseudomonas aeruginosa RW9, using a renewable and non-food competitive, palm oil mill effluent (POME) sludge oil as a carbon source. Various carbon and nitrogen sources were introduced into the mineral salt medium to optimize biosurfactant production. The results demonstrated that P. aeruginosa RW9 successfully generated 1.57 g/L of rhamnolipids (RLs) biosurfactant. Liquid chromatography-mass spectrometry (LC-MS) analysis confirmed the presence of mono-RLs and di-RLs congeners. Furthermore, the RLs produced from POME sludge oil exhibited a significant reduction in surface tension, reaching 28.55 mN/m, and demonstrated efficient emulsification of diesel, with an emulsion index of up to 56.6 %. This research underscores the promising potential of using POME sludge oil as a sustainable substrate for RLs production. This approach not only adds value to a vastly available resource but also contributes to the production of environmentally friendly biochemicals.

COMPARING PHOSPHORUS RECOVERY AND OPTIMUM TIME DIGESTION FROM SINGLE AND MIXING SUBSTRATES BY USING ANAEROBIC MESOPHILIC DIGESTION TECHNIQUE

Phosphorus (P) is considered a limited and non-renewable mineral source that is essential in our daily lives, especially for the agricultural industry to produce fertilizer. Food Waste (FW), Palm Oil Mill Effluent Sludge (POMES), and Water Treatment Sludge (WTS) are wastes that are claimed to contain nutrients such as P. One of the methods that can be used to recover P is through the Anaerobic Mesophilic Digestion (AMD) technique. Therefore, this study was carried out to investigate the highest P recovery and time digestion from single and mixing substrates. The physicochemical and biological properties of raw FW, POMES, and WTS were determined, and it was reported that wastes were suitable to undergo the AMD process. Mesophilic conditions 350C (±1) were used as the appropriate conditions for the anaerobic bacteria (AB) to reproduce and grow. Results for single substrates found that POMES recovered the highest P with 57.88% (±1.24), and optimum digestion was at day 12. While FW and WTS recovered P with 31.94% (±0.76) and 26.47% (±1.51), respectively, the optimum digestion times for both wastes were at days 18 (FW) and 21 (WTS), respectively, which were longer than POMES. In mixing substrates, FW-POMES contributed to the highest P recovery value with 68.34% (±1.49), and the optimum time digestion was on day 9. Followed by WTS-POME, FW-WTS, and FW-POMES-WTS with values of 60.42% (±2.12) (day 15), 48.05% (±2.51) (day 8), and 20.85% (±1.33) (day 3), respectively. The better synergetic effect within anaerobic bacteria (AB) in mixing substrates with FW-POMES could eventually influence the highest P removal from the substrate in a short period of time. Moreover, this study also provides information on new strategies used in recovering P. Keyword(s) : Phosphorus recovery, Food Waste; Palm Oil Mill Effluent Sludge; Water Treatment Sludge; Anaerobic Mesophilic Digestion

Phytoremediation of Heavy Metal on Entisols and Plant Uptake Amended with Palm Oil Mill Effluent (POME) Sludge

Palm oil mill effluent (POME) sludge was derived from about 50% of wastewater effluent of fresh fruit bunch (FFB) productions. The objective of this study is to determine the effect of contaminant status which was applied with POME sludge on Entisols and plant uptake of maize growth. POME sludge obtained from the Jengka 8 FELDA Palm Oil was used in this study. The maize (Zea mays) was used as a test crop and planted in Rasau series soil (Entisols). The soil, leaves and stem samples were air-dried, homogenized and sieved. Heavy metal analysis identified the existence of Cu, Cr, Cd, Zn, Pb, Ni and Mn elements by the sequential extraction procedure using optical emission spectrometry (ICP-OES). The physicochemical of POME sludge showed that most heavy metals in each treatment fulfilled the WHO/FAO standard and were safe for human consumption. After applying treatments on Entisols, a small amount of Cu, Cr, Zn, Pb, Ni and Mn was retrieved from the exchanges phase. Small amount of Cr, Ni and Mn were identified in the stems and leaves. Zn, Cd, Pb and Cr were not detected in the bioavailable forms, while Cu was only available in the mixing ponds sludge samples. The results showed that most heavy metal properties contained low residual fractions from the soil and plant uptake in stems and leaves. The application of POME sludge in agricultural practices might offer a sustainable utilization of waste materials in the oil palm plantation.

Biohythane production from pineapple peel using Methanosarcina mazei enhanced with palm oil mill effluent (POME) sludge in single‐stage anaerobic digestion

AbstractBiohythane production via single‐stage anaerobic digestion (AD) is an effective way for sustainable energy recovery from lignocellulosic biomass. In this paper, biohythane was produced through the AD process from pineapple peel waste substrate using purely cultured Methanosarcina mazei with the enhancement of palm oil mill effluent (POME) sludge as the inoculum. This study focuses on the effects of the lignocellulosic pre‐treatment method, the addition of POME sludge into M. mazei culture medium as inoculum, and various operational conditions (food to microorganisms (F/M) ratios, temperature, pH) on gas production performances. The experimental results indicate that these parameters influenced the efficiency of biohythane production by producing the peak maximum biohythane production rate values (HPRmax) and (MPRmax), H2:CH4 = 1.93:0.67 L/L‐d, and biohythane yield (HY) and (MY), H2:CH4 = 1.18:0.55 mL/L‐substrate. This study demonstrates that biohythane gas (H2 + CH4 + CO2) production from pineapple waste can be accelerated by M. mazei only with the enhancement of POME sludge through single‐stage AD system under mesophilic batch process conditions.

The synthesization of activated carbon from electrocoagulated palm oil mill effluent sludge for wastewater treatment

The oil palm industry in Malaysia is certainly the one of economic and agricultural drives for the country. Nevertheless, despite the obvious benefits that it possesses, oil palm mill also significantly contributes to environmental degradation. It generates massive amounts of solid waste, wastewater, and air pollution from its production and processing processes. Activated carbon (AC) as an adsorbent has been used widely to remove pollutants in wastewater. Many attempts have been made to produce economically accessible AC. This paper explores the idea of producing an AC, a value-added product, sludge produced from the electrocoagulation process of palm oil mill effluents (POME) through chemical activation. AC has different applications after its discovery as a solid and reliable adsorbent. Its microporous structure, high surface reactivity, and surface area make it versatile and viable for removing pollutants from aqueous solutions. The electrocoagulated sludge-based AC is characterized by its surface characteristics, elemental compositions, surface morphology, and available functional group. To validate the adsorption capacity of electrocoagulated sludge-based AC, textile dye wastewater treatment was carried out to test the efficiency of AC. Results indicate that TSS in textile dye wastewater decreased as the adsorbent dosage increased. The values of TSS removal by AC from H3PO4 activation decreased steadily compared to KOH activation. Meanwhile, the color removal percentage decreased when the dye concentration increased. AC from H3PO4 activation has higher color removal percentage. This shows that AC from H3PO4 activation has better adsorption due to its more extensive surface area. From BET analysis, AC by H3PO4 activation offers a higher surface area, 36.1017 m2/g, compared than KOH activation, 8.9460 m2/g. Extensive surface area has a higher tendency to adsorb contaminations. The findings of this work confirmed the potential use of electrocoagulated sludge-based AC as an alternative and economically adsorbent for effective dye pollution removal in wastewater.

Preliminary Investigation of Different Types of Inoculums and Substrate Preparation for Biohydrogen Production

A pre-culture stage is required to obtain robustly-dividing cells with high hydrogen (H2) production capabilities. However, a step-by-step process for biohydrogen production is scarcely reported, mainly from palm oil wastewater. Therefore, this study developed a guideline to find the best inoculum heat treatment conditions and implement the selected conditions for biohydrogen production using palm oil wastewater. This study used raw palm oil mill effluent (POME) and POME sludge as substrate and inoculum, respectively. Our findings reveal that 80 °C and 30 min were the best conditions for inoculum heat treatment. When testing the conditions on POME sludge and inoculating with raw POME (28 g COD/L) at 37 °C (reaction temperature), 24 h (reaction time), and pH 5.5, 34 mL H2/d was recorded. A slight increase (1.1-fold) was observed compared to 5 g COD/L POME co-digested with 5 g/L glucose (31 mL H2/d). This discovery indicates that raw POME is a potential source for biohydrogen production under anaerobic fermentation and can be directly used as substrate up to 30 g COD/L. The proposed guideline could also be implemented for different organic wastes for biohydrogen production study.

I​nfluence of Treated POME Sludge Vermicomposting on Soil Physicochemical Properties and Maize Growth Performances

Background: Transforming the abundance of palm oil mill effluent (POME) sludge into beneficial substances such as an organic amendments is vital in the recycling of waste. Vermicomposting from treated POME sludge (TPS) was evaluated on the effect of soil physicochemical properties, crop performances and to determine the best treatment effect on the biomass of the hybrid grain maize (Zea mays L.). Methods: The experimental layout was designed in a randomized complete block design (RCBD). The grain maize cultivated in Bungor series soil (Ultisol) comprising of (T1) control (NPK fertilizer), (T2) 1 kg of vermicompost, (T3) 2 kg vermicompost, (T4) 1 kg TPS and T5 (2 kg TPS) with six replications, for a period of 100 days from June to September 2019. Half of the NPK fertilizer dosage applied from the recommended practices. Result: The treatments with 50% reduction of NPK rate significantly (p less than 0.05) affected soil physicochemical properties. The dry matter production, crop performance analysis (net photosynthesis, stomata conductance and transpiration rate) and root weight density were also increased significantly using 2 kg of vermicompost treatment. Vermicompost application demonstrated the best treatment effect on soil properties and grain maize productivity. Utilization of POME sludge waste into organic amendment through vermicomposting approach would become very crucial practices to be adopted in reducing the abundance waste.

Effect of Initial Carbon to Nitrogen Ratio on the Degradation of Oil Palm Empty Fruit Bunch with Periodic Addition of Anaerobic Palm Oil Mill Effluent Sludge

The objective of this study was to evaluate the effect of different initial carbon to nitrogen (C/N) ratios on the organic matter degradation during active co-composting of oil palm empty fruit bunch (OPEFB) and palm oil mill effluent (POME) anaerobic sludge. The initial C/N ratio was varied from 25:1, 35:1 and 45:1. Co-composting was conducted by periodic addition of sludge to maintain the moisture content and enrich the compost product. The organic matter (OM), carbon to nitrogen profile and compost maturity index were analysed. The results showed that the initial C/N ratio of 35:1 was the best initial C/N ratio. In addition, the C/N ratio of 35:1 gave the best OM degradation. The appropriate amount of initial C/N ratio coupled with the correct composting process parameters such as daily mixing, suitable pH and moisture content improved the organic matter degradation. It reduced the composting time from 40-60 days to 30 days.

Spent Labisia pumilia as a bulking agent for palm oil mill sludge composting

This paper aims to explore the potential use of herbal residue, spent Labisia pumilia (SLP) (also known as Kacip Fatimah) as a bulking agent for palm oil mill effluent sludge (POMES) composting to obtain biofertilizer. Natural aerobic decomposition through the passive aeration approach was implemented by using the bin-composting technique. POMES and SLP mixture were placed in three compost bins with a different weight ratio of 1:3, 1:1 and 3:1. Throughout the experimental period, samples were regularly taken out for physical analysis i.e. pH, temperature and moisture content. On day 90, samples were analyzed for nutrients analysis. The result indicated that ratios 1:1 and 1:3 illustrated typical pH and temperature profiles; meanwhile, ratio 3:1 vice versa for pH profiles. An in-depth analysis of the nutrients composition summarized that the C/N ratio for all mixture samples is within the standard limit for mature compost, and nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg) and calcium (Ca) are sufficient to utilize as a biofertilizer. In conclusion, it is feasible to utilize SLP as a bulking agent to improve palm oil mill sludge composting and eventually produce biofertilizer. Thus, it offers an alternative in handling solid waste from palm oil mills.

Diluted Luria-Bertani medium vs. sewage sludge as growth media: comparison of community structure and diversity in the culturable bacteria.

Because colony formation is essential to seek bacterial functions by the direct observation of phenotype, the diversification of colony formation for culturable bacteria is a big challenge in the research field of Environmental Biotechnology. In this study, the biodiversity of cultivable bacteria (colony or liquid culture) was compared by using Luria-Bertani (LB) medium and waste sewage sludge (WSS) under different dilutions and temperatures. When WSS was used as a bacterial source, whereas the highest number of colonies was found at the concentration of WSS (5%), a particular concentration of LB (10%) or WSS (1%) as a growth medium showed the best number of the operational taxonomic units (OTUs) of colonies. The results of bacterial community structure indicated that there are 1, 8, and 12 bacterial genera found uniquely in the agar plates of LB, 10% LB, and 5% WSS. By contrast, when palm oil mill effluent sludge was used as a bacterial source, the effect of dilution was different with WSS. When comparing the biodiversity between colonies and liquid culture, a high OTU value was observed in the colonies on the plate. In addition, 30°C showed the highest number of colonies in LB, 10% LB, and 5% WSS whereas the best OTUs were observed at 37°C for LB and 10% LB, and at 25°C for 5% WSS. This study demonstrates the diversification of cultivable bacteria through the number of OTUs in diluted LB medium and WSS, which is beneficial to isolate a unique bacterial strain.Key points• Impacts of diluted LB medium and WSS for colony formation were determined.• Difference of concentration of LB and WSS made different effects on colony formation.• Temperature change affected on diluted LB and WSS as media.

Production of Bricks from Sludge of Palm Oil Mill Effluent (POME)

Malaysia has been recognized in recent decades as one of the world's leading palm oil producers and exporters. The number of palm oil mills multiplies each year, increasing the capacity of fresh fruit bunch waste or effluent discharged. Countless numbers of research and development, as well as implementation, have been dedicated to advancing the pollution control technologies. Most of the research is to treat and manage liquid and solid waste generated from palm oil mills. The main reason for such tremendous efforts is that the waste coming from palm oil mills has been declared as one of the pollution sources in the world. Thus, the purpose of this study was to utilize treated palm oil mill effluent (POME) sludge from the electrocoagulation process to produce bricks. Here, three different dilution rates, which was 60%, 90% and 100% of POME concentration have been analyzed in the electrocoagulation process, respectively. After the electrocoagulation process, the characteristics of POME effluents were evaluated, and the treated POME sludge was collected. Instead of being discarded after the treatment, the treated waste sludge from the electrocoagulation process was used to make bricks. Three different bricks labelled (A, B and C) from treated POME sludge from the electrocoagulation process (60%, 90% and 100%) were fabricated. These bricks have been analyzed based on the JKR Standard Specifications for Building Works. Data obtained showed that the compressive strength for the bricks (A, B and C) after seven days were 6.076, 8.233, and 6.344 N/mm2. Meanwhile, the bulk density of the bricks (A, B and C) were 2247.92, 2233.95, and 2094.33 kg/m3. The results showed that the compressive strength for these brick samples had met the JKR Standard Specification for Building Works of 5.2 N/mm2. It can be deduced that the bricks from treated POME can be a greener product compared to the traditional bricks. Moreover, the concept of a circular economy is adapted in this study to eliminate waste for a long-term sustainable environment.

Incorporation of Rice Husk Ash with Palm Oil Mill Wastes in Enhancing Physicochemical Properties of the Compost

Rice husk ash (RHA), palm oil mill effluent (POME) sludge and decanter cake can be utilized together in compost production to minimize the environmental pollution. This study aims to evaluate the role of different composition of RHA in enhancing the physicochemical properties of palm oil-based compost. The composts were prepared by mixing different composition of RHA, in the range of 0% to 30%, with 1:1 (wt/wt) weight ratio of POME sludge and decanter cake. The moisture content, water holding capacity, pH, nitrogen (N), phosphorus (P), potassium (K), silica (Si) contents, and C:N ratio of raw materials were analyzed by using CHNS and WDXRF analyzers. The composting process was conducted in compost containers for 60 days, in which the temperature and pH of the composts were monitored daily. The finished composts were analyzed for physicochemical properties as same as raw materials. For physical properties of finished composts, RHA30 had the highest moisture content and water holding capacity which was 1.9 to 23.8% (wt/wt) and 4.2 to 26.8% higher compared to other finished composts, respectively. For chemical properties, the highest N and P contents were recorded by control compost. However, for K and Si content, the elements were found to be higher in RHA10 and RHA30, respectively, compared to other finished composts. Overall, RHA, POME sludge and decanter cake combination in compost production can create a well-balanced condition for the compost to perform effectively as an organic fertilizer. The addition of 5% to 10% RHA in compost formulation made from palm oil mill wastes is suggested to achieve the desirable condition.

Synergistic effect of ultrasonic and microwave pretreatment on improved biohydrogen generation from palm oil mill effluent

This study aims to investigate the effect of the ultrasonic, microwave, and combined ultrasonic-microwave pretreatment of palm oil mill effluent (POME) sludge before fermentation to analyze hydrogen (H2) production and chemical oxygen demand (COD) removal efficiency in batch fermentation. Experimental results showed that the pretreatment of sludge (ultrasonication, microwave, and ultrasonication-microwave pretreatment) had positively influence the H2 production and COD removal efficiency during fermentation as compared to control one (without any pretreatment). Combined ultrasonication-microwave pretreatment of POME sludge was shown to be more effective for increasing both H2 production and COD removal from POME with the highest cumulative H2 and COD removal efficiency of 4080 mL H2/L-POME and 75.56%, respectively. The improvement observed for cumulative H2 production and COD removal was 12.14% and 21.42%, respectively, compared to the control one. These observations concluded that the POME sludge pretreatment with ultrasonication-microwave irradiation could be an effective strategy for improved treatment of POME with simultaneous production of H2.

Co-pyrolysis of Palm Empty Fruit Bunch and Palm Kernel Shell with Palm Oil Mill Effluent (POME) Sludge

In Malaysia, the largest contributor to biomass is from the palm oil sector. Therefore, palm-based biomass has been extensively studied for bioenergy applications. Fast pyrolysis of biomass provides a liquid fuel called bio-oil, which has many potential uses. However, a low pH of bio-oil made a challenge to utilize as it is. Therefore, in this study, empty fruit bunch (EFB) and palm kernel shell (PKS) were subjected to co-pyrolysis with POME sludge individually. The reason behind this was that the bio-oil derived from EFB and PKS are acidic, whereas bio-oil from POME sludge is basic. Hence, it was hypothesised that through the co-pyrolysis, bio-oil with lower acidity might be obtained. Chemical characterization revealed that POME sludge contains alkali and alkaline earth metals (AAEMs), which may play a significant role in influencing the weight loss of EFB and PKS, also the bio-oil yield. The co-pyrolysis of EFB and PKS with POME sludge at different ratios were initially carried out via thermogravimetric analysis (TGA). Results showed that for the co-pyrolysis of PKS, a positive synergistic effect was observed when 50 wt.% of POME sludge was employed. Then, pyrolysis and co-pyrolysis experiments were carried out in a fixed bed reactor at 600°C. The bio-oil yield obtained from PKS was 44.5 ± 0.7 wt.%. In contradiction to TGA studies, the bio-oil yield for co-pyrolysis of PKS and POME sludge showed a negative synergistic effect.

Treatment of palm oil mill effluent (POME) by coagulation flocculation process using peanut–okra and wheat germ–okra

Coagulation–flocculation has been proven as one of the effective processes in treating palm oil mill effluent (POME), which is a highly polluted wastewater generated from palm oil milling process. Two pairs of natural coagulant–flocculant were studied and evaluated: peanut–okra and wheat germ–okra. This research aims to optimize the operating parameters of the coagulation flocculation process in removing turbidity, total suspended solid and chemical oxygen demand (COD) from POME by using a central composite design in the Design Expert® software. Important parameters such as operating pH, coagulant and flocculant dosages were empirically determined using jar test experiment and optimized using response surface methodology module. Significant quadratic polynomial models were obtained via regression analyses (R2) for peanut–okra (0.9355, 0.9534 and 0.8586 for turbidity, total suspended solids and COD removal, respectively) and wheat germ–okra (0.9638, 0.9578 and 0.7691 for turbidity, total suspended solids and COD removal, respectively). The highest observed removal efficiencies of turbidity, total suspended solids and COD (92.5, 86.6 and 34.8%, respectively, for peanut–okra; 86.6, 87.5 and 43.6%, respectively, for wheat germ–okra) were obtained at optimum pH, coagulant and flocculant dosages (pH 11.6, 1000.1 mg/L and 135.5 mg/L, respectively, for peanut–okra; pH 12, 1170.5 mg/L and 100 mg/L, respectively, for wheat germ–okra). The coagulation flocculation performance of peanut–okra and wheat germ–okra were comparable to each other. Characterizations of the natural coagulant–flocculant, as well as the sludge produced, were performed using Fourier transform infrared, energy-dispersive X-ray spectroscopy and field emission scanning electron microscope. More than 98% of water was removed from POME sludge by using centrifuge and drying methods, indicating that a significant reduction in sludge volume was achieved.

Influence of Treated Palm Oil Mill Effluent Sludge on Maize (Zea mays) Growth Performance and Gas Exchange

The presence of abundant oil palm residues in Malaysia prompted the need to utilize this waste to avoid environmental pollution. This waste was abundant at the oil palm mill and accounted for almost 50% of production. The study was conducted to determine the morphological effect of Palm Oil Mill Effluent (POME) sludge on the maize growth performance and gas exchange. Physicochemical, growth morphology and gas exchange was measured after treated with POME sludge from different treatment pond systems: Mixing, anaerobic, facultative, algae and dumping. The results indicated the pH, C, and CEC of mixing the < anaerobic < facultative < algae < dumping ponds. There was a significant presence of macronutrient (N, Mg, Ca, Fe, S) in the treated POME sludge, contrary to the presence of heavy metal (Cd, Cu, Ni and Pb) elements which were not significantly different in all the treatments and lower than WHO/FAO standard. Root Shoot Ratio (RSR) and Specific Leaf Area (SLA) indicated significant difference in biomass accumulation and yield compared to the control. The gas exchange variable was a significant difference on stomata conductivity (Gs) and transpiration rate (E). However, the POME sludge from the facultative, algae and dumping ponds showed positive correlations between net photosynthesis, stomata conductivity and transpiration rate. Indeed, the increased transpiration rate (E) was correlated with stomata conductance (Gs) after treatment with anaerobic, facultative, algae and dumping ponds. In conclusion, the POME sludge amendment was able to increase the maize biomass and yield.

English

The underutilized and improper management of wastewater such as palm oil mill effluent sludge (POME) sludge might create pollution and give a negative impact towards the environment. This study was aimed to evaluate the effect of shear strength parameter and root length density of maize on Entisols applied with POME sludge as a soil amendment. The maize was planted on Rasau soil series (Entisols) amended with different POME sludge treatment systems from various ponds (mixing, anaerobic, facultative, algae, and dumping). Standard direct shear box test was used to identify the cohesion (c) and angle of internal friction (φ) after application of treatments. The bulk density, porosity, moisture content, organic matter, root length and root density of Zea mays L. (Hibrimas) applied with POME sludge from dumping pond (DP), aglae pond (ALP) and facultative pond (FP) were significantly difference against the control treatment. The positive effect of root length and root length density (RLD) treated with POME sludge from the dumping pond was 26% and 38% compared to the other treatments. The results highlighted that roots enhanced soil shear strength by reducing the cohesion and increased the angle of internal friction component. The shear strength analysis showed that high shear strength of normal stress at 500.72 kN/m2 was measured from the dumping pond's POME sludge treatment after maize harvesting. The POME sludge from the DP, ALP and FP was ameliorating some nutrients deficiencies for the plant growth and improved the root length density. In conclusion, the POME sludge from the DP indicated the high shear strength and root length densities due to the adequate nutrients for roots distribution and maize growth.

Anaerobic Co-Digestion of Palm Oil Mill Waste Residues with Sewage Sludge for Biogas Production

Empty fruit bunches (EFB), palm oil mill effluent (POME), sewage chemical sludge and sewage biological sludge were evaluated for methane production under liquid-state anaerobic digestion (L-AD) and solid-state anaerobic digestion (SS-AD). The highest methane yield of 456 mL CH4 g-1VS was achieved from co-digestion POME with sewage chemical sludge at a ratio of 99:1 under L-AD. The highest methane yield of 18 mL CH4 g-1VS was achieved from co-digestion EFB with sewage chemical sludge at a ratio of 95:5 and EFB with sewage biological sludge at a ratio of 95:5 under SS-AD. An increasing of sewage sludge content of 6-42% in both AD systems resulted in decreasing of methane yield. The L-AD system has 2-3 times higher volumetric methane productivity than the SS-AD system. The electricity production from 1-tonne a mixture of POME and sewage chemical sludge or sewage biological sludge would be 218 MJ or 60 kWh of electricity. Anaerobic co-digestion POME with sewage sludge has great potential for biogas production.

Kinetics and Mechanisms for Copyrolysis of Palm Empty Fruit Bunch Fiber (EFBF) with Palm Oil Mill Effluent (POME) Sludge

Copyrolysis of biomass is one of the potential options to improve the quality of bio-oil. In this study, different types of feedstock, palm empty fruit bunches fiber (EFBF) and palm oil mill effluent (POME) sludge, were conducted via thermogravimetric analysis. The thermogravimetric behavior of EFBF and POME sludge blends (EFBF:POME sludge mass ratio of 100, 90, 75, 50, 25, and 0%) were subjected to different heating rates of (5, 10, 20, 30, 40 °C/min) with a nitrogen (N2) purge of 20 mL/min to simulate pyrolysis conditions. As the percentage of POME sludge in the blend increases, the thermogravimetric data and thermogravimetric derivative profiles shifted from EFBF to that of POME sludge gradually. A higher mass loss rate of EFBF upon devolatilization indicates the higher reactivity than that of POME sludge. During copyrolysis, a positive synergistic effect was observed. All the samples experienced three pyrolysis stages, and for each stage, the mechanisms responsible were determined. The third order kin...

Ameliorating Plant Available Water by Addition of Treated Palm Oil Mill Effluent (POME) Sludge on Entisols

Palm oil mill contributed a significant benefit to agro-based industry and social-economic for Malaysia. The treated POME sludge was produced from the open treatment ponds and palm oil mill effluent (POME) without any treatment is considered as a polluted wastewater. This study is to determine the effect of POME sludge on Entisols for plant available water (PAW). The data obtained from this study were selected to measure physicochemical parameters (bulk density, porosity, compaction, organic matter), hydraulic parameter (hydraulic conductivity, hydraulic capacity and water retention) to determine the PAW. The POME sludge from different treatment ponds (control, mixing pond, anaerobic pond, facultative pond, algae pond and dumping pond) was applied to the Zea mays (Hibrimas) as a test crops. The results showed that maize treated with POME sludge from the dumping pond indicated significant difference on soil organic matter, bulk density, porosity, soil compaction and plant available water compared to mixing and anaerobic ponds. As a conclusion, POME sludge from the dumping might improve soil physical properties of Entisols. The dumping pond sludge has significant potential to be used as an organic amendment for plant growth in the future.