Boiler Ash Research Articles

Comparative effect of boiler ash-urea mixture on soil properties, growth, and yield of Cocoyam (Colocasia esculenta)

One major constraint in utilizing boiler ash in agriculture as fertilizer is its low nitrogen content. A field trial was conducted to evaluate comparatively the effect of integrating boiler ash with urea and two rates of NPK fertilizer on soil, growth, and yield of cocoyam Colocasia esculenta (Taro) in Iwollo, Southeastern Nigeria. The experiment was laid out in a randomized complete block design (RCBD) with three replications and five treatments which comprised of a control (no fertilizer), two levels of NPK 15:15:15 (100, 200kgha-1) combinations of two levels of broiler ash (5, 10 t ha-1) with 70 kg ha-1 urea. The plots were planted with cocoyam cormels. Data on soil properties after harvest, growth, and yield characteristics were collected and subjected to one-way analysis of variance, and significant treatments mean separated by Fisher's least significant difference at 5% level of probability. Results obtained showed that the treatments did not exert significant influence on the soil physical properties evaluated, but differed significantly (p<0.05) in pH, phosphorus, and percent base saturation. Comparatively, integrating the low level of BA (10tha-1) with 70 Kg ha-1 urea reduced soil acidity, increased soil available P, and percent base saturation but did not significantly influence growth and tuber yield of cocoyam. Application NP. K fertilizer at the rate of 200 Kg ha-1 was a higher number of cormels plant-1 (32.6), cormel yield (47.8 Mg ha-1), and corm yield (4.53 Mg ha-1). The fertilization effects of broiler ash – urea mixture at the rate applied in the study were masked by innate soil ability to supply plant-available nutrients, but significant reduction in pH and enrichment in available P suggest that the broiler ash – urea mixture may have a positive effect under more acidic and P deficient conditions.

Mercury emission and adsorption characteristics of fly ash in PC and CFB boilers

The mercury emission was obtained by measuring the mercury contents in flue gas and solid samples in pulverized coal (PC) and circulating fluidized bed (CFB) utility boilers. The relationship was obtained between the mercury emission and adsorption characteristics of fly ash. The parameters included unburned carbon content, particle size, and pore structure of fly ash. The results showed that the majority of mercury released to the atmosphere with the flue gas in PC boiler, while the mercury was enriched in fly ash and captured by the precipitator in CFB boiler. The coal factor was proposed to characterize the impact of coal property on mercury emissions in this paper. As the coal factor increased, the mercury emission to the atmosphere decreased. It was also found that the mercury content of fly ash in the CFB boiler was ten times higher than that in the PC boiler. As the unburned carbon content increased, the mercury adsorbed increased. The capacity of adsorbing mercury by fly ash was directly related to the particle size. The particle size corresponding to the highest content of mercury, which was about 560 ng/g, appeared in the range from 77.5 to 106 µm. The content of mesoporous (4–6 nm) of the fly ash in the particle size of 77.5–106 µm was the highest, which was beneficial to adsorbing the mercury. The specific surface area played a more significant role than specific pore volume in the mercury adsorption process.

Industrial symbiosis in Tanzania: A case study from the sugar industry

The concept of industrial symbiosis (IS) offers enormous potential for more sustainable manufacturing processes. This paper sets out to explore the IS forms occurring at a case study of the Kilombero Sugar Company Limited (KSCL), the largest sugar refinery in Tanzania; and identify the underlying factors based on the data collected through key informant interviews, observational site visits, and relevant documentary reviews. Findings reveal an evolving IS network at KSCL involving physical exchanges of bagasse, molasses, filter cake, and boiler ash and utility sharing among seven co-located units. Through these modest internal IS arrangements, KSCL has optimized resource use, thereby minimizing negative environmental impacts inherent from emissions, as well as generating additional revenues from resource recovery, in particular the alcohol distillery unit. Results also show that KSCL’s industrial ecosystem is fragile due to limited functional and structural diversity. We identify several drivers and barriers as possible leverage points. The lessons from KSCL are expected to provide a valuable reference for IS development in Africa.

Low-Temperature Pretreatment of Organic Feedstocks with Selected Mineral Wastes Sustains Anaerobic Digestion Stability through Trace Metal Release.

A low-cost approach for enhancing mesophilic (37 °C) anaerobic digestion (AD) of organic waste using a low-temperature (37 °C) pretreatment with different mineral wastes (MW) was investigated. A higher and stable methane production rate, in comparison to MW-free controls, was achieved for 80 days at organic loading rates of 1-2 g VS/L·d, using a feed substrate pretreated with incinerator bottom ash (IBA). The boiler ash and cement-based waste pretreatments also produced high methane production rates but with some process instability. In contrast, an incinerator fly ash pretreatment showed a progressive decrease in methane production rates and poor process stability, leading to reactor failure after 40 days. To avoid process instability and/or reactor failure, two metrics had to be met: (a) a methanogenesis to fermentation ratio higher than 0.6 and (b) a cell-specific methanogenic activity to cell-specific fermentation activity ratio of >1000. The prevalence of Methanofastidiosum together with a mixed community of acetoclastic (Methanosaeta) and hydrogenotrophic (Methanobacterium) methanogens in the stable IBA treatment indicated the importance of Methanofastidiosum as a potential indicator of a healthy and stable reactor.

Synthesis of Nano-silica from Boiler Ash in the Sugar Cane Industry using the Precipitation Method

Synthesis of Nano-silica from Boiler Ash in the Sugar Cane Industry using the Precipitation Method

Effect of Use of Substituted Oil Palm Shell Boiler Ash on Cement and Substituted Glass Powder on Fine Aggregate on Concrete Compressive Strength

This research aims to determine the effect of palm shell boiler ash substituted in cement and glass powder substituted on fine aggregate in concrete mixes on compressive strength and slump values and to determine the usefulness of the concrete. This research used an experimental method with 9 variations of substitution materials, a total of 60 samples of cube-shaped test specimens measuring 15cmx15cmx15cm. The variation of Oil palm shell boiler substitution used is 0%, 6%, 8%, and 10%, and for glass powder substitution variation is 0%, 5%, 10%, and 15%. From the results of the compressive strength test conducted on the 7th day, the substitution of 8% Oil palm shell boiler Ash and 10% glass powder or variation E received the highest compressive strength result of 19,593 MPaWhile on the 28th day, substitution of 6% oil palm shell boiler ash and 5% glass powder or variation A received the highest compressive strength yield of 22,630 MPa.

The role of silica-containing agro-industrial waste as reinforcement on physicochemical and thermal properties of polymer composites

This study was conducted to determine the influence of the oil palm boiler ash (OPBA) reinforcement on the microstructural, physical, mechanical and thermal properties of epoxy polymer composites. The chemical composition analysis of OPBA revealed that it contains about 55 wt.% of SiO2 along with other metallic oxides and elements. The surface morphology of OPBA showed angular and irregular shapes with porous structures. The influence of OPBA as a reinforcement in epoxy composite was studied with varying filler loadings (10–50 wt.%) and different particle sizes (50–150 μm). The result showed that the incorporation of OPBA in composites has improved the physical, mechanical and thermal properties of the epoxy matrix. The highest physical and mechanical properties of fabricated composites were attained with 30 wt.% loading and size of 50 μm. Also, thermal stability and the percentage of char residue of the composite increased with increasing filler loading. Furthermore, the contact angle of OPBA reinforced epoxy composites increased with the increase of filler loading. The lowest value of the contact angle was obtained at 30 wt.% of filler loading with the OPBA particle size of 50 μm. The finding of this study reveals that the OPBA has the potential to be used as reinforcement or filler as well as an alternative of silica-based inorganic fillers used in the enhancement of mechanical, physical and thermal properties of the epoxy polymer composite.

Improving the methane productivity of anaerobic digestion using aqueous extracts from municipal solid waste incinerator ash

This study investigated the effects of mineral waste extracts (MWE) on laboratory-scale two-stage anaerobic digesters treating synthetic organic waste. MWE was prepared as aqueous extracts from different ash samples (incineration bottom ash (IBA), fly ash (FA) and boiler ash (BA) taken from a municipal solid waste incineration plant. At 20 days hydraulic retention time, all three MWE stimulated hydrogen production in their respective acidogenic reactor by around 35% (c.f. control acidogenic reactor), whilst no difference was seen in the methane productivity of the linked methanogenic reactors (average 527 ± 45 mL CH4/g VS, including control methanogenic reactor). Following a step reduction in hydraulic retention time from 20 to 10 days and a doubling of the organic loading rate from 2.5 g to 5 g VS/L. d, no significant change was seen in hydrogen production (p > 0.05) in the acidogenic reactor amended with MWE from IBA and BA, or the control acidogenic reactor. However, the acidogenic reactor receiving MWE from FA had 45% lower hydrogen productivity. The step change in hydraulic retention time and organic loading rates led to the failure of most methanogenic reactors (≤100 mL CH4/g VS), however, the one receiving feed containing MWE from IBA showed stable performance without signs of failure, and had higher volumetric methane productivity, albeit at lower methane yields (370 ± 20 mL CH4/g VS). 16S rRNA analysis using the Illumina sequencing platform revealed acidogenesis by Lactobacillaceae in the acidogenic reactor and syntrophic acetate oxidation by Synergistaceae linked to enrichment of the candidatus genus Methanofastidiosum, in the stable methanogenic reactor receiving MWE from IBA.

Predicting the effects of integrating mineral wastes in anaerobic digestion of OFMSW using first-order and Gompertz models from biomethane potential assays

Previous studies found mineral wastes (MW; incineration bottom ash (IBA), cement based waste (CBW), Fly ash (FA) and boiler ash (BA) are a promising resource for the macro-/micronutrients necessary for anaerobic digestion (AD) processes. The current study used first-order and modified Gompertz models from BMP assays to investigate the effects of integrating MW on the AD of OFMSW at 37 °C. Results from the first-order model showed a 45% increase in the specific growth rate of microorganisms (μ) in the MW- supplemented BMP compared to the control. Gompertz model results indicated that the IBA, CBW, FA and BA BMP amended assays obtained the highest K values (45–54 mL CH4 g VS−1 d−1) than the control (K ∼ 31 mL CH4 g VS−1 d−1), with no significant adverse effects of co-digestion of OFMSW with MW on the length of the lag phase (λ) in BMP assays (λ = 1.89 ± 0.07 days for IBA, CBW and BA amended assays compared to 1.5 ± 0.01 days for the control). However, FA amended assays had a greater λ value (3.66 ± 0.1 days). The MW provided both alkalinity and released several trace elements at concentrations within the optimal ranges for methanogenic archaea.

The Abrasive Properties of Coal Power Plants Ash and Slag Materials

Ash and slag materials (ASM), formed during the combustion of coal in thermal power plants, have abrasive properties, which are manifested during the operation of boiler units, ash collection, ash and slag removal. These properties must be considered to ensure durable trouble-free operation of thermal power plants. On the other hand, these properties can be used when planning measures for ash and slag material disposal. The results of experimental-industrial tests of ash and slag materials abrasive properties are presented in this paper. It was shown that, when cleaning metal surfaces of various shapes from old paint coatings, the consumption of crushed coal slag per 1 m2 of the surface being treated is on average 4.8 times less than the consumption of sand, the time of surface treatment with slag is on average 2.45 times less than with the use of sand in similar conditions. The empirical formulas to evaluate the technical and economic efficiency of using ash and slag materials as an abrasive in industrial applications are given.

Utilization of the trash biochar and waste of sugarcane to improve the quality of sandy soil and growth of sugarcane

An abundance of sugarcane trash (ST) can be converted into soil amendment to improve soil quality. Pot research was carried out in Malang, East Java from October 2013 to October 2014. The research aimed to study changes in the properties of sand-textured soil due to the application of trash biochar and other sugarcane wastes, as well as its effect on sugarcane growth. The study was arranged in a randomized block design with six treatments and three replications. Treatment includes: 1) ST biochar 10 t ha−1; 2) boiler ash 10 t ha−1; 3) ST compost 10 t ha−1; 4) ST biochar 5 t ha−1 + ST compost 5 t ha−1; 5) boiler ash 5 t ha−1 + ST compost 5 t ha− 1; and 6) control (without soil amendment). The treatments improved the physical and chemical properties of sandy soil, namely bulk density, total porosity, available moisture content, aggregate stability, organic-C, total-N, available-P, exchangeable-K, and CEC. However, the improvement of this soil did not affect the growth and yield of sugarcane. Further research is needed to study the effect of residues from the application of biochar on ratoon sugarcane, and research on sugarcane development land.

Mechanical Properties of Natural Rubber Compounds with Oil palm boiler ash and Carbon Black as a Filler

This study aims to determine the mechanical properties of natural rubber compounds with variations of OPBA nanoparticle fillers and carbon black. Preparation methods for natural rubber compounds using Open Mill. Indonesian rubber standard -20 (SIR-20) mixed with anti-oxidants, activators, curing agents, accelerators and OPBA nanoparticle fillers size 56.31 nm and commercial Carbon black type (N330) with variations (0,2,4,6 and 8)% wt. The results showed that tensile strength increased with the increase in the composition of OPBA nanoparticles and carbon black, as well as the elongation of break and hardness. The best composition of OPBA filler 8% wt showed a hardness of 52 Shore A, a tensile strength of 1.7 MPa, an elongation of break 150%. The best composition of carbon black 8% wt filler with a hardness of 55 Shore A, a tensile strength of 2.5 MPa, elongation breakdown of 140%.

Hydrothermal Leaching of Nickel, Uranium and the Remaining Vanadium from Alkali Treated Boiler Ash Residue using Citric Acid

In this study; the boiler ash was subjected to a digestion process using citric acid solution. Previously the ash was treated with NaCO3-NaHCO3 solution for vanadium leaching. In this step about 85% of vanadium content was leached while nickel was not dissolved using the carbonate solution. The ash after vanadium dissolution was digested using citric acid for nickel and the remaining vanadium beside uranium dissolutions. Experimental results have shown that maximum metals dissolution obtained using 0.3M citric acid was 81, 85 and 89% respectively. The resultant liquor solution was subjected to successive nickel, vanadium and uranium separations. Firstly; the leach liquor is treated with dimethylglyoxime solution to precipitate Ni species. Secondly; the filtrate after Ni separation is treated with TBP/kerosene solvent for uranium extraction. Finally, the aqueous solution is treated with ammonium chloride to precipitate the vanadium content.

Microstructure and thermal properties of natural rubber compound with palm oil boilers ash for nanoparticle filler

This study aims to determine the properties of natural rubber compounds by varying the Oil Palm Boiler Ash (OPBA) nanoparticles with variations (0,2,4,6 and 8) wt%. The preparation method for natural rubber compounds uses Open Mill by mixing Indonesian Rubber Standard-20 (SIR-20) with anti-oxidants, activators, preservatives, accelerators, and OPBA nanoparticle fillers. The results showed thermal properties with Differential Scanning Calorimetric (DSC) increased melting point and the presence of cross bonds with increasing OPBA composition compared without filler. The distribution of compounds occurs even with the addition of OPBA filler. The results of the XRD diffraction pattern analysis of natural rubber composites without fillers amorphously shaped, but with the addition of OPBA fillers, the diffraction pattern showed a crystal structure. The FTIR graph shows that there is no significant difference between compounds with and without fillers.

PENGARUH KOMPOS TANDAN KOSONG KELAPA SAWIT DAN ABU BOILER DI LAHAN GAMBUT TERHADAP PERTUMBUHAN DAN PRODUKSI SEMANGKA (Citrullus lanatus)

The research aims to obtain a combination of doses of palm oil empty bunches compost (POEBC) and boiler ash to increase the growth and yield of watermelons on peatlands. The experiment was conducted in factorial form using Completely Randomized Design (CRD). The first factor was POEBC consisting of 4 levels (0; 7,5; 10 and 12,5 ton/ha) and the second factor is boiler ash consisting of 4 levels (0; 2,5; 5 and 7,5 ton/ha), and each combination was repeated 3 times. Parameters observed were plant length, stem diameter, flowering age, the weight of fruit per plant, and yield per plot (15 m2). The results showed that the combination of POEBC dosage 12,5 ton/ha and boiler ash dosage 7,5 ton/ha increased the plant length, stem diameter, the weight of fruit per plant 453%, yield per plot 139% and flowering 8 days faster compared to control (without treatment).

New Experimental Evaluation Strategies Regarding Slag Prediction of Solid Biofuels in Pellet Boilers

Pellet boilers and pellet stoves are widely used for heat production. But in most cases, only specific wood pellets with a low ash content are approved due to the increased risk of slagging and limited deashing capacity. The ash fusion test (AFT), according to prCEN/TS 15370-1, is currently the only standard method for the prediction of slagging. This method is not feasible for all biomass fuel types, since sometimes the characteristic temperatures cannot be determined or the characteristic shapes do not occur for temperature determination. Furthermore, the method is costly and requires complex instrumental infrastructure. Hence, a demand for more expressive or more rapid methods to characterize slag formation potential of fuels is often claimed. Based on a literature study, four such laboratory test methods were chosen, partly adapted, and then experimentally investigated. These methods included thermal treatment of the fuel itself or the ashes of the fuel and were the rapid slag test, CIEMAT, the slag analyzer, and the newly developed pellet ash and slag sieving assessment (PASSA) method. Method performance was practically assessed using 14 different biomass fuel pellets, which were mainly from different assortments of wood, but also herbaceous or other nonwoody fuels. The results from the tests with these four alternative methods were evaluated by comparing to both results from standard AFT and results from full-scale combustion tests performed over a maximum of 24 h. Seven different pellet boilers were assessed, of which one boiler was used to apply all 14 test fuels. According to the granulometric ash analysis (i.e., the ratio of >1 mm-fraction toward total ash formed), the sensitivity of the new test methods to depict slagging phenomena at a suitable level of differentiation was assessed. Satisfactory conformity of the boiler ash assessment (reference) was found for both, the slag analyzer and the PASSA method. The latter may, in particular, be seen as a promising and relatively simple low-input procedure, which can provide more real-life oriented test results for fixed-bed combustion. The standardized AFT could, however, not sufficiently predict the degree of slag actually formed in the reference boiler, particularly when only wood fuels are regarded.

Co-gasification and co-combustion of industrial solid waste mixtures and their implications on environmental emissions, as an alternative management

The primary sludge produced by the wastewater treatment plant of a pulp and paper mill has high physicochemical heterogeneity, which limits the efficiency of thermochemical methodologies for the final disposal of this residue. As a solution, co-pelletization of the Primary Sludge (PS) with two other principal Industrial Solid Residues (ISRs) of the plant, Coal Boiler Ashes (CBA) and Wood Waste chips (WW), was proposed as a way to valorize the PS for energy use, while reducing dewatering costs. The energy potential was evaluated through a series of thermal co-processing tests of disaggregated and pelletized mixtures. Due to their differing fixed-carbon-to-volatile-material ratios, combining the ISRs resulted in a reduction of up to 45% of the mass of the ISR generated, improving the disposal conditions and achieving a minimum thermal power of 5.0 MJ/Nm3 through gasification. Finally, the environmental implications of the thermal co-processing of the wastes were assessed, finding very low impacts due to pollutant emissions, in accordance with the legal environmental regulations in force in Colombia.

Utilization of sugar factory wastes as an ameliorant on sugarcane seedling media with bud chips technique

Filter mud and boiler ash are sugar factory wastes that have benefits as a soil amendment. The huge quantities of unutilized filter mud and boiler ash was a fuel of this study. The aim of this research is to analyze the effect of sugarcane wastes to planting media for bud chips sugarcane nurseries. This experiment was used randomized group design with three different planting media, consisting of filter mud and soils (P1), boiler ash and soils (P2), and soils only (P3). The sugarcane seeds used were bud chips sugarcane with Bululawang varieties. The results showed that the application of sugar factory wastes in planting media was able to enhance the sugarcane plant growth, including the amount of leaves, the diameter of stem, wet and dry weight of plants in 8 weeks after planting. Sugarcane wastes did not significantly improve the height of plants dan plant roots. Combinations of filter mud and soils has the highest value of vegetative growth compared to other media.

Karakterisasi Pelet Pupuk Organik Berbahan Slurry Limbah Cair Pabrik Kelapa Sawit Sebagai Pupuk Slow Release

The high availability of slurry from palm oil mill effluent, solid, and boiler ash with their nutrient contents make those three materials are potential to be processed become organic fertilizer in the form of pellet so it tends to has slow release characteristic. This research aims to analyize characteristic of organic fertilizer pellet from slurry of palm oil mill effluent as slow release fertilizer by analyzing its physical characteristics, NPK content, and NPK releasing rate in soil.Slurry was processed become solid fertilizer in the form of pellet using pellet mill with tapioca adhesive 5%. Pellet was made from slurry, solid, and boiler ash which were mixed with ratio 1:1:1, 1:2:2, 2:1:1, 2:2:1, 2:1:2, 1:0:0 (only slurry). This research ware analysis of physical characteristis (length, diameter, and density) and analysis of NPK content. N content was analyzed using Kjeldahl method, P content using spectrophotometer, and K content using Atomic Absorbtion Spectrophotometer (AAS). Then it was continued with analysis of NPK releasing content in latosol soil.The average length of pellets was 31–48 mm, diameter was 5,42 – 6,28 mm, water content was 0,426 – 0,976%, particle density was 1,04 – 1,34 g/cm3, and bulk density 0,49–0,63 g/cm3. Organic fertilizer pellet in six formulas contained N+P2O5+K2O about 5,93–8,08%. The highest content (8,08%) was produced from 1:0:0 pellet, followed by 2:1:2 formula (7,53%), and 1:2:2 formula (7,25%). Until the 10th days, the releasing of N element was about 1,99 – 3,18%, P element was 0,063– 0,075%, and K element was 43,54 – 62,26%.

PENGARUH PEMBERIAN ABU BOILER TERHADAP PERTUMBUHAN DAN HASIL BAWANG MERAH (Allium ascalonicum L.) DI LAHAN GAMBUT

The aim of research to study the effect of Boiler ash origin palm oil mills (PKS) and the pulp on growth and yield of onion (Allium ascalonicum L.) on peatland. Research conducted at the experimental farm, Faculty of Agriculture, University of Riau, Rimbo Panjang village, Kampar District, Riau Province from August to November 2015. The study using the split-plot design (Split Plot Design), as the main plot, Boiler ash consists of two levels (plant origin MCC and pulp), and the subplot is boiler ash doses (0, 3, 6, and 9 tons/ha). Parameters measured were plant height, tuber number, the weight of tuber per hill, and tuber yield per m2. The results showed that plant height increased markedly in the application of 3 tons/ha ash from two sources, the number of tubers per clump sample increased markedly on the application of 6 tons/ha ash from PKS, as well as tuber weight per hill and tuber yield per m2 tends to increase with the application 3-9 tonnes/ha, the increase is greater with higher doses of ash from both sources.