Limestone Particle Size Research Articles

Effects of the Updated National Emission Regulation in China on Circulating Fluidized Bed Boilers and the Solutions To Meet Them

The advantage of circulating fluidized bed (CFB) boilers in China is their ability to utilize low rank coal with low cost emission control. However, the new National Emission Regulation (NER) issued in early 2012 brings much more stringent challenges on the CFB industries, which also causes much attention from other countries. Based on the principle of a CFB boiler and previous operating experience, it is possible for the CFB boilers to meet the new NER and maintain the advantage of low cost emission control, while, more influences should be considered in their design and operation. To meet the requirement of the new NER, the fly ash collector should adopt a bag house or combination of electrostatic precipitator and bag filter to ensure dust emissions of less than 30 mg · Nm(-3). For SO2 emission control, the bed temperature should be strictly lower than 900 °C to maintain high reactivity and pores. The limestone particle size distribution should be ranged within a special scope to optimize the residence time and gas-solid reaction. At the same time, the injecting point should be optimized to ensure fast contact of lime with oxygen. In such conditions, the desulfurization efficiency could be increased more than 90%. For lower sulfur content fuels (<1.5%, referred value based on the heating value of standard coal of China), increasing Ca/S enough could decrease SO2 emissions lower than that of the new NER, 100 mg · Nm(-3). For fuels with sulfur content higher than 1.5%, some simplified systems for flue gas desulfurization, such as flash dryer absorber (FDA), are needed. And the NOx emissions of a CFB can be controlled to less than 100 mg · Nm(-3) without any equipment at a bed temperature lower than 900 °C for fuels with low volatiles content (<12%), while for fuels with high volatiles, selective non-catalytic reduction (SNCR) should be considered. Due to the unique temperature in CFB as well as the circulating ash, the efficiency of SNCR could reach as high as 70%. The Hg emission of CFB is very low for the new NER due to its innate property.

Hydration and strength development in ternary portland cement blends containing limestone and fly ash or metakaolin

This paper reports the influence of limestone particle size and the type of (partial) cement replacement material on hydration and the mechanical properties of cement pastes. Limestone powders having median particle sizes of 0.7, 3, and 15μm, at OPC replacement levels between 0% and 20% (volume basis), and two other replacement materials of differing reactivity (i.e., Class F fly ash or metakaolin) at replacement levels between 0% and 10% (volume basis), are used to proportion ternary binder formulations. Fine limestone accelerates early-age hydration, resulting in comparable or better 1-day compressive strengths, and increased calcium hydroxide (CH) contents as compared to pure cement pastes. The incorporation of metakaolin in conjunction with limestone powder alters the heat release (i.e., kinetic) response significantly. A ternary blend of this nature, with 20% total cement replacement demonstrates the highest 1-day strength and lowest CH content. Thermal analysis reveals distinct peaks corresponding to the formation of the carboaluminate phases after 28days in the limestone–metakaolin modified pastes, whereas the incorporation of similar levels of fly ash does not change the response markedly. It is shown that the synergistic effects of limestone and metakaolin incorporation results in improved properties at early ages, while maintaining later age properties similar to that of traditional OPC systems.

Batch Thermodynamics and Kinetic Study for Removal of Cationic Dye from Aqueous Solution Using Iraqi Limestone

Model using Iraqi limestone as an adsorbent has been investigated. The influences of equilibrium time, limestone dosage, limestone particle size, pH of solution, adsorption isotherms and temperature on adsorption performance have been experimentally verified by a batch method. The adsorbent used in this study exhibited a good adsorption potential at initial pH 10, temperatures 28oC, particle size 75 µm, limestone dosage 0.1g for equilibrium time 140 min. The removal efficiency and distribution coefficient have also been determined for the adsorption system as a function of dosage of the adsorbent. The experimental results are described by Langmuir and Freundlich isotherm models. Experimental results show that the kinetic model of pseudo-second order provided a good description of the whole experimental data more than the kinetic of the Lagergren-first order. Keyword: Batch adsorption, Methyl Violet, Thermodynamics and Kinetic models.

Impacts of Limestone Multi-particle Size on Production Performance, Egg Shell Quality, and Egg Quality in Laying Hens.

This experiment was conducted to evaluate the effects of single or multi-particle size limestone on the egg shell quality, egg production, egg quality and feed intake in laying hens. A total of 280 laying hens (ISA brown) were used in this 10-wk trial. Laying hens were randomly assigned to 4 treatments with 14 replications per treatment and 5 adjacent cages as a replication (hens were caged individually). The experimental treatments were: i) L, basal diet+10% large particle limestone; ii) LS1, basal diet+8% large particle limestone+2% small particle limestone; iii) LS2, basal diet+6% large particle limestone+4% small particle limestone; iv) S, basal diet+10% small particle limestone. The egg production was unaffected by dietary treatments. The egg weight in S treatment was lighter than other treatments (p<0.05). The egg specific gravity in S treatment was lower than other treatments (p<0.05). The eggshell strength and eggshell thickness in S treatment were decreased when compared with other dietary treatments (p<0.05). The laying hens in LS1 and LS2 treatment had a higher average feed intake than the other two treatments (p<0.05). Collectively, the dietary multi-particle size limestone supplementation could be as efficient as large particle size limestone.

The effect of dietary calcium concentration and particle size on performance, eggshell quality, bone mechanical properties and tibia mineral contents in moulted laying hens

1. A total of 72 H&N Brown Nick laying hens, 76 weeks of age (moulted at 60 weeks of age), were randomly assigned into a 3 × 3 factorial arrangement with three limestone particle sizes and three dietary Ca concentrations (30, 36 and 42 g/kg Ca); with 8 replicates per treatments, and one hen (individual) per experimental unit. 2. Particle sizes of the limestone were: distributions smaller than 2 mm (Fine), between 2 to 5 mm (Medium), and larger than 5 mm (Large). The fine, medium and large limestone particles were all obtained from the same source, and sieve sizes used had screen sizes 2 mm and 5 mm. 3. The different concentrations of dietary Ca, particle size or interactions had no significant effect on egg production, egg weight, egg mass, feed intake or feed conversion ratio. 4. The concentrations of dietary Ca and particle sizes had no significant effect on egg breaking strength, eggshell as % by weight of whole egg or eggshell thickness. The interactions between Ca concentrations and particle sizes had a significant effect on eggshell breaking strength, but not on other parameters. 5. Different dietary particle sizes had no significant effect on the Ca, P and Mg mineral contents of eggshell. While the different concentrations of Ca in diets had a significant effect on the P content of eggshell, they had no significant effect on Ca and Mg contents. 6. Different dietary concentrations of Ca had a significant effect on shear stress, and Ca and Mg contents of tibiae, but not other parameters. Also, dietary particle sizes had a significant effect on shear stress and Ca contents of tibiae. The interaction between Ca concentrations and particle sizes had a significant effect on tibia shear force and Ca content. 7. According to the results of this study, moulted brown laying hens should be fed 36 g/kg Ca and a medium limestone particle size (2–5 mm) in the diet to maintain performance, eggshell and bone quality.

Níveis de cálcio e granulometria do calcário sobre o desempenho e a qualidade da casca de ovos de poedeiras comerciais

Effects of calcium levels and limestone on laying hen performance and egg shell quality. An experiment was carried out to evaluate the influence of calcium levels and combinations of limestone particle sizes on the laying performance and egg shell quality of hens. Three hundred and sixty Hy-Line laying hens of 57 weeks of age were used, distributed in a randomized design in 3x5 factorial arrangement (3.75, 4,15 and 4,55% of calcium in the diet and 0, 25, 50, 75 and 100% of replacement of limestone powder) with 4 replicates, each consisting of 6 hens. Egg production, feed conversion, egg weight, and strength and thickness off egg shell were influenced by diet calcium levels. No single effect of limestone particle size replacement was found in the studied parameters. The average egg weight was improved when different diet calcium levels, interacting with different combinations of limestone particle sizes, were used.

Effect of the levels of calcium and particle size of limestone on laying hens

This experiment was conducted to evaluate the effect of levels of calcium (Ca) and particle size of limestone (LS) for laying hens. It was used 216 Dekalb White laying hens at 25 to 49 weeks of age in a completely randomized design in a 3 × 2 factorial arrangement, composed of three levels of calcium (3.92, 4.02 and 4.12%) and two particle sizes of limestone (thin - 0.60 mm; and thick - 1.00 mm), resulting in 6 treatments with six replicates of six birds. There was no significant effect of levels of calcium and limestone particle size neither of the interaction calcium × particle size for feed intake, egg weight, specific gravity, shell thickness, shell percentage, Haugh unit, calcium and phosphorus digestibility and percentage of digestive tract. Production, mass, conversion by mass and conversion by egg dozen had their best results with 4.12% of calcium in the diet. Percentage of gizzard and feed intake observed at 3:00 p.m. improved as limestone granulometry improved from 0.60 to 1.00 mm. There was an interaction effect among calcium level and limestone granulometry for breaking strength of tibia, bone density, length of the small intestine and feed intake at 6:00 a.m.; 9:00 a.m., 12:00 p.m., 6:00 p.m. and 9:00 p.m., respectively. It is recommended the addition of 4.12% of calcium and limestone in the thick granulometry (1.00 mm) for a better performance of commercial laying hens. More studies are needed to elucidate the mechanisms involved in the alteration of nutritional behavior of laying hens in response to changes in the levels of calcium and in the granulometry of limestone in the rations.

Lime Brust of Sintering Bricks of Purple Sandy Shale: the Effect of Limestone Particle Size

Simulating current sintering process in local brickkilns, Hengyang region, Hunan Province, China, at 800°C, througt indoor sintering experiment on a series of brick samples of purple sandy shale, in which particle sizes of limestone are &gt;-1Φ, &gt;0Φ, &gt;1Φ, &gt;2Φ, &gt;3Φ and &gt;4Φ, respectively, it is concluded that the following: (1) Limestone granularity is a crucial factor affecting the quality of sintering bricks of purple sandy shale. Under different particle sizes, the critical content of limestone causing lime brust of sintering bricks is distinct, and lowers with the increasing in limestone granularity. (2) When limestone granularity is different, its impact way on the quality of sintering bricks is also distinct. The more coarse limestone granularity is, the more concentrative the swelling stress produced by the hydration of free CaO is, the more easily lime brust occurs. On the contrary, the more fine limestone granularity is, the more dispersive the swelling stress is, there is the more help to reduce or eliminate the occurrence of lime brust. (3) In view of the relationship between limestone granularity and the critical content of limestone giving rise to lime brust of sintering bricks, the production practice can be effectively guided.

Effect of particle size of limestone on Ca, Mg and K contents in soil and in sward plants

Liming increases crop production through improved soil conditions in acidic soils. Among the effects of liming, increased availabilities of alkaline and alkaline-earth cations are worth mention. These availabilities may be affected by the particle size of applied limestone, which influences lime reactivity. The effects of particle size and application schedule of magnesium limestone were investigated on extractable Ca, Mg and K in soil, their concentrations in sward plants and dry-matter yield. Magnesium limestone of various particle sizes was applied to experimental plots at a rate of 3 t ha-1, a grass-clover sward was sown, and the plots were monitored during three years. The finest limestone (&lt; 0.25 mm) in a single application yielded the highest soil Ca and Mg concentrations extracted by Mehlich-3 and NH4Cl. The same limestone split in three annual doses was less effective. Plots treated with the coarsest limestone (2-4 mm) did not differ from control plots. Liming had no effect on potassium, either in soil or plants. Soil concentrations of Ca, Mg and K extracted by Mehlich-3 and NH4Cl were correlated with each other (r = 0.76, 0.75 and 0.67, respectively). NH4Cl extracted more Ca than Mehlich-3, while the latter extracted more Mg and K than NH4Cl. Soil Ca, Mg and K extracted by NH4Cl were also correlated to water extractions. Mg concentration in plants correlated to soil Mg extracted by NH4Cl or by water. Neither the concentrations nor the total contents of Ca and K in plants correlated with extractable soil Ca and K. The total dry matter yield was not affected by liming. The yield of sown species was higher in plots treated with the finest limestone than in plots limed with the coarsest limestone. Cations extracted by water or NH4Cl explained the variance of dry matter yield.

Effects of dietary calcium levels and limestone particicle size on the performance, tibia and blood of laying hens

A total of 405 23-week-old ISA® Brown layers were distributed in a completely randomized experimental design in a factorial arrangement with nine treatments consisting of three dietary calcium levels (3.5, 3.75, and 4.5%) and three limestone particle sizes (100% fine limestone (FL), 70% FL + 30% coarse limestone (CL) and 50% (FL) + 50% (CL)), with nine replicates of five birds per cage. The following parameters were evaluated: percentage of lay, defective eggs, egg weight, egg mass, feed intake, feed conversion ratio (per kg eggs and per dozen eggs), and mortality. Dietary Ca levels significantly affected lay, with birds fed diets containing 4.5% calcium producing less eggs as compared to those fed 3.0 and 3.75% Ca. Egg production linearly decreased as dietary Ca levels increased, but blood Ca levels (mg/L) increased in 28-week-old birds. The interaction of dietary Ca levels and limestone particle sizes resulted in a reduction in tibial ash Ca content as dietary Ca levels increased and as fine limestone was replaced by coarse limestone. It is concluded that a dietary Ca level of 3.75% and 100% fine particle limestone are required to maintain adequate egg production and available Ca blood level.

Automated online measurement of limestone particle size distributions using 3D range data

Fully automated online measurement of the size distribution of limestone particles on conveyor belt is presented based on 3D range data collected every minute during 13 h of production. The research establishes the necessary analysis and measurement capabilities to facilitate automatic control of rock crushing or particle agglomeration processes to improve both energy efficiency and product quality. 3D data from laser triangulation is used to provide high resolution data of the surface of the piled limestone particles. The 3D data is unaffected by color variation in the material and is not susceptible to scale or perspective distortion common in 2D imaging. Techniques are presented covering; sizing of particles, determination of non-overlapped and overlapped particles, and mapping of sizing results to distributions comparable to sieving. Detailed variations in the product sieve-size are shown with abrupt changes when the size range of the limestone particles is changed.

Limestone Particle Size and Liming Scheduling Influence Soil Properties and Pasture Production

Liming is a common practice in Galician (NW Spain) soils devoted to pasture production. Although many studies have established the right liming rates, there is a lack of information concerning the ideal particle size for optimal agronomic results. This study aims to evaluate the effects of particle size (2-4, 0.5-2, 0.25-0.5, <0.25 mm) of magnesium limestone as well as the application schedule (in a single application or split in 3 yearly applications) on the proprieties of an acid soil in Galicia and on the yield and quality of pasture growing on the soil during the 2 years after liming. The soil proprieties were monitored seasonally, and the pasture yield and nutritional contents were determined in summer and autumn. The soil analysis showed that the plots treated with a single application of the finest limestone exhibited the highest pH (pH water 5.05-5.53), and the lowest exchangeable Al (<10% Al saturation throughout the period of study), the highest concentrations of exchangeable Ca (8.40-10.18 cmol(+) kg−1) and Mg (1.39-1.71 cmol(+) kg−1) and the highest effective cation exchange capacity (11.2-13.7 cmol(+) kg−1). In contrast, plots treated with the coarsest limestone had values similar to control plots. The highest production of total dry matter and, especially, the highest yield of sown species were found in the plots receiving the finest limestone (0.75-1.10 t ha−1 dry matter in summer harvest versus 0.30-0.75 t ha−1 in control plots). Available P, exchangeable cations (K and Ca), and pH explain a high percentage of the variance of these parameters. The Mg concentrations and the total contents of Ca and Mg in plant tissues were significantly higher in the plots treated with the finest limestone.

Effect of limestone particle size on bone quality characteristics of hens at end-of-lay

A study was conducted to determine the effect of different limestone particle sizes in layer diets on bone quality characteristics at end-of-lay hens. Calcitic limestone (360 g Ca/kg DM) that is extensively used in commercial poultry diets was obtained from a specific South African source. Limestone particles were graded as small ( 1.0 mm) have a beneficial effect on improving the mechanical properties of bone of older laying hens.

Effect of limestone particle size on egg production and eggshell quality of hens during late production

A study was conducted to determine the influence of different particle size limestone in layer diets on egg production and eggshell quality during the later stages of egg production (>54 weeks of age). Calcitic limestone (360 g Ca/kg), consisting of small ( 2+ to laying hens for egg production and eggshell quality at end-of-lay, provided that the dietary Ca content satisfies the requirements of the laying hen.

The Effect of Limestone Particle Size on the Performance of Three Broiler Breeder Purelines

A 40-wk study was conducted to assess the effects of limestone particle size on the production performance, skeletal integrity and Ca/P balance of three broiler breeder purelines. A flock of LINE A, LINE B and LINE C broiler breeders were reared according to Cobb 500 guidelines (Cobb-Vantress, 2005) and transferred to a production house at 21 wks of age. Each line was split into two groups consisting of 66, 68 and 62 hens for the LINE A, LINE B and LINE C lines, respectively and fed a diet that differed only in the inclusion of either large (3489.7 microns; 38.5% solubility) or small particle (185.5 microns; 58.8% solubility) limestone. Production performance, egg quality, breeder skeletal integrity, reproductive performance, progeny performance and Ca/P balance were monitored. LINE B produced the most eggs per hen housed and highest egg number, followed by LINE C and LINE A, respectively. Egg weight, specific gravity and shell weight were also superior in LINE B compared to the other purelines. The % P retention did not differ across purelines, but Ca retention was also highest in LINE B. Breeder skeletal integrity and progeny bone quality were higher in LINE C. The addition of large particle limestone in lieu of small particles did not provide a consistent effect in production performance but significantly improved shell quality (P = 0.0013), bone quality (P = 0.0341). The large genetic differences in purelines compared to parent stock may uniquely alter the effects of particulate calcium on production performance; yet large particle limestone provided the boost in shell quality and bone quality reported by others. In summary, LINE A, LINE B and LINE C purelines utilize Ca and P differently and have unique genetic potential for hatching egg production, egg shell quality, breeder bone ash and progeny bone ash.

Influence of limestone particle size on iron ore sinter properties and productivity

AbstractIron ore fluxed sinter is the main ferrous burden of Jindal south west steel limited (JSWSL) blast furnaces. In sinter plant fluxes including limestone and dolomite are added to improve the sinter properties of iron ore and to provide an appropriate slag composition of the blast furnace. The raw material grain size affects the sinter process considerably because the sinter productivity and quality are strongly dependent on the green permeability of the bed, which is determined by the particle size distribution of the raw materials, the granulation effectiveness and by the sintering process itself. It is well‐known that in fluxed sinter, the size of limestone affects productivity and physical and metallurgical properties of the sinter. It is therefore necessary to understand the role of limestone particle size on sinter properties and productivity. In the present work laboratory sintering experiments have been carried out with different levels of limestone mean particle size (from 0.14 to 1.83mm) to understand the influence of limestone particle size on mineralogy, productivity, physical and metallurgical properties of the sinter. Sinter productivity increased with increasing limestone mean particle size due to improved sinter bed permeability. Sinter with limestone mean particle size of 1.25 to 1.52 mm yielded better sinter strength and lower RDI compared to sinter with smaller or larger limestone mean particle size. Higher sinter strength is due to better and uniform distribution of limestone particles, and better bed permeability enabled easy assimilation and effective distribution of calcium ferrite phases. The improvement in sinter RDI is due to change in mineralogy of the sinter compared to coarser and finer limestone mean particle size.

Influence of limestone particle size on performance and egg quality in laying hens aged 24–36 weeks and 56–68 weeks

One hundred and twenty ISA Brown hens aged 24–36 weeks and 120 ISA Brown hens aged 56–68 weeks were used to study the influence of limestone particle size and the animal's age on laying performance and egg quality. Two diets were used: a diet containing calcium carbonate in fine limestone particles (diet LF with limestone particles <0.5 mm), and a diet containing calcium carbonate in coarse limestone particles (diet LC with 91% of particles larger than 0.8 mm and smaller than 2.0 mm). The experimental unit consisted of a group of 10 hens, thus each treatment was replicated six times per age group. Hen-day egg production was higher and egg weight lower in young hens than in old hens (P<0.001). In younger hens, hen-day egg production was 87.0 and 89.4% in birds fed LF and LC, respectively. Corresponding hen-day egg production values in older hens were 73.5 and 79.9%. Lower egg production in hens aged 56–68 weeks was compensated in part by higher egg weight which was 62 and 63 g in younger hens fed diets LF and LC, respectively, and 67 and 68 g in older hens fed diets LF and LC, respectively (P<0.001). In younger and older hens, feeding the LC diet increased shell weight by 0.2 and 0.2 g (P<0.001), shell thickness by 4 and 8 μm (P<0.001), shell Ca content by 2 and 2 mg/g DM (P=0.003), albumen height by 0.2 and 0.3 mm (P=0.003), and Haugh units by 0.8 and 0.2 (P=0.014), respectively. No increase in the shell breaking strength was observed. It can be concluded that LC with a particle size of 0.8–2.0 mm should be considered rather than fine ground limestone when formulating diets for laying hens both in the early and the late phase of production.

LIMESTONE PARTICLE SIZE AND RESIDUAL LIME CONCENTRATION AFFECT PH BUFFERING IN CONTAINER SUBSTRATES

The objective was to quantify how the concentration and particle size of unreacted “residual” limestone affected pH buffering capacity for ten commercial and nine research container substrates that varied in residual calcium carbonate equivalents (CCE) from 0.3 to 4.9 g CCE·L−1. The nine research substrates contained 70% peat:30% perlite (by volume) with dolomitic hydrated lime at 2.1 g·L−1, followed by incorporation of one of four particle size fractions [850 to 2000 μm (10 to 20 US mesh), 250 to 850 μm (20 to 60 US mesh), 150 to 250 μm (60 to 100 US mesh), or 75 to 150 μm (100 to 200 US mesh)] of a dolomitic carbonate limestone at 0, 1.5 or 3.0 g·L−1. Substrate-pH buffering was quantified by measuring the pH change following either (a) mineral acid drenches without plants, or (b) a greenhouse experiment where an ammonium-based (acidic) or nitrate-based (basic) fertilizer was applied to Impatiens wallerana Hook. F. Increasing residual CCE in commercial substrates was correlated with greater pH buffering following either the hydrochloric acid (HCl) drench or impatiens growth with an ammonium-based fertilizer. Research substrates with high applied lime rate (3.0 kg·m−3) had greater pH buffering than at 0 or 1.5 g·L−1. At 3 g·L−1, the intermediate limestone particle size fractions of 250 to 850 μm and 150 to 250 (20 to 60 or 60 to 100 US mesh) provided the greatest pH-buffering with impatiens. Particle fractions finer than 150 μm reacted quickly over time, whereas buffering by particles coarser than 850 μm was limited because of the excessively slow reaction rate during the experimental periods. Addition of acid from either an ammonium-based fertilizer or HCl reduced residual CCE over time. Dosage with 40 meq acid from HCl per liter of substrate or titration with HCl acid to substrate-pH of 4.5 were well-correlated with pH buffering in the greenhouse trials and may be useful laboratory protocols to compare pH buffering of substrates. With nitrate fertilizer application, residual CCE did not affect buffering against increasing pH. Residual limestone is an important substrate property that should be considered for pH management in greenhouse crop production under acidic conditions.

Effects of aggregate size and alkali content on ASR expansion

Attempts to model ASR expansion are usually limited by the difficulty of taking into account the heterogeneous nature and size range of reactive aggregates. This work is a part of an overall project aimed at developing models to predict the potential expansion of concrete containing alkali-reactive aggregates. The paper gives measurements in order to provide experimental data concerning the effect of particle size of an alkali-reactive siliceous limestone on mortar expansion. Results show that no expansion was measured on the mortars using small particles (under 80 µm) while the coarse particles (0.63–1.25 mm) gave the largest expansions (0.33%). When two sizes of aggregate were used, ASR-expansions decreased with the proportion of small particles. Models are proposed to study correlations between the measured expansions and parameters such as the size of aggregates and the alkali and reactive silica contents. The pessimum effect of reactive aggregate size is assessed and the consequences on accelerated laboratory tests are discussed.

Effect of liming with different sized limestone on the forms of aluminium in a Galician soil (NW Spain)

The aim of this study was to evaluate the effects of the particle size (2–4 mm, 0.5–2 mm, 0.25–0.5 mm and less than 0.25 mm) of magnesium limestone and the method of application (in a single dose or split in three yearly doses), on the forms of Al in the solid and liquid phases of an acid Galician soil destined for pasture production. Monitoring the experimental plots over a period of 3 years showed that the plots treated with a single application of the finest limestone (< 0.25 mm) exhibited the highest pH and the lowest concentrations of exchangeable Al, with less than 10% Al saturation throughout the period of study. The average values of pH in water along the period of study were 5.30 in the most effective treatment and 5.06 in control plots. The average values of aluminium saturation were 6.5% in the most effective treatment and 16.9% in control plots. One year after liming, the plots treated with a single application of the finest limestone presented also the highest concentrations of weakly stable organo-aluminium complexes in the solid phase and of organically bound Al in the soil solution, as well as the lowest concentrations of labile Al, while no Al 3+ (considered the most toxic Al species) was detected. Over time non-crystalline inorganic Al tended to precipitate, apparently at the expense of exchangeable Al and/or Al bound to the organic matter. The application of the finest limestone split in three doses (until completion of 3 t ha − 1 in the third year of the study) was less effective than the application of a single dose. The plots treated with the coarsest limestone (between 2 and 4 mm) and the control plots provided similar results for all parameters throughout the three years of the study. In the former the exchangeable Al was higher than 20% and the concentration of labile Al was the highest of all plots.