Cake Height Research Articles

Fine material filtration using conventional pressure and steam pressure: a relationship between filter cake height to crack formation and residual moisture content

Crack formation is an undesired phenomenon encountered frequently during the filtration process, especially in fine particulate filter cakes. This phenomenon causes disadvantages related to the dewatering efficiency and washing efficiency. The filter cake height has not only an effect on crack formation but also meaning in the economic and operational of filtration. In this research, Limestone and Coal are the chosen fine powder materials to survey the effect of this factor during conventional pressure filtration (CPF) and steam pressure filtration (SPF). The permeability ratio is suggested to quantify cracking while the saturation and the residual moisture content indicate the water remaining. Test results show lower dewatering efficiency as well as an increasing trend of probability and degree of cracks when the filter cake becomes thicker. By visual observation, macro- and micro-cracking are described for shrinkage behavior on filter cake. The delamination was also mentioned and observed after filtration. Steam pressure filtration (SPF) is introduced as one of the methods to reduce the degree, even prevent the formation of cracks as well as improve the dewatering efficiency.

Experimental study on mechanical dewatering and displacement washing of filter cakes with inhomogeneous cake geometry

The influence of cake geometry on mechanical gas dewatering and displacement washing of filter cakes is investigated experimentally. For this purpose, five cake geometries are considered. The results show that the dewatering kinetics are independent of cake geometry within the limits of measurement accuracy. Further investigations demonstrate that an inhomogeneous cake geometry negatively influences displacement washing, which can be quantified in a wash diagram. Compared to flat filter cakes used as reference, non-uniform cake heights increase the needed amount of wash liquid to achieve the same cake purity in the dispersion and diffusion regime. This research underlines the importance of ensuring that filter cakes have homogeneous properties to maintain sustainability of industrial filtration processes.

Research on the factors affecting the product filtration efficiency in mineral processing plants

Filtration is a long-standing process but the technology has changed slowly, mainly based on the increase in filtration pressure and changes in the characteristics of filter media. The problem is high moisture remains product, requiring more expensive technologies (thermal drying) and long processing times. In the mineral processing industry, not only concentrates but also tailings need to be dewatered. The test samples were Cam Duong apatite concentrated and tailing ore, Ta Phoi copper concentrated and Sin Quyen tailing ore, Cua Ong fine coal, and Dak Nong red mud. All samples’ properties have been defined by sieving analyses, SEM method, and gravitational density measurement. Then, samples were experimented with using the Nutsche high-pressure filtration in the variable operational parameters. While the sludge concentration affected the specific resistance, the filter cake height and filtration pressure did not affect as much. At the suitable condition (homogeneous filter cake, 1 bar pressure difference, and 50 grams solid weight), the specific resistance and residual moisture content of the filter cake are around 2.5x10-12÷1.5x10-13 m-2, 15÷25%, respectively. Through the test results, some recommendations are mentioned in order to perfect the process and scale up for industrial production.

Potential of avocado puree and orange fleshed sweet potato for wheat-based cake production

Avocado puree is rich in unsaturated healthy fats, being a better alternative to the saturated bakery fats usually used in cake production. Hence, the potential of avocado puree as a fat replacer and the use of composite flours made from wheat and orange fleshed sweet potato (OFSP) for cake production were investigated. Various ratios of substitution of the OFSP flours and avocado puree were used. The proximate composition of the flour blends, physical properties, colour and sensory acceptability of the cake were evaluated. Moisture content (6.17-9.17%) was low, such as to support stability during storage. The 100% OFSP flour had the highest content of ash, crude fat, and carbohydrate (1.50, 4.17, and 82.76%, respectively). The 100% wheat flour showed the highest protein content (15.42%) and fibre content (1.01%), whereas 100% OFSP had the lowest contents (4.53 and 0.21%, respectively). Significant variation of the cake height and weight were noticed among different formulations considered in this experiment. The cake produced with 90% wheat and 10% OFSP was the most preferred, with the highest overall acceptability (8.40). Therefore, wheat flour supplemented with 10% OFSP produces a batter which possesses the potential to create a health-beneficial cake and provide economic advantages to the nation by reducing wheat importation.

Розробка оптимальних складів вугільних шихт для трамбування. Повідомлення 2. Дослідження вугільних шихт з оцінкою якості одержаного коксу

The article describes the results of the study of the developed coal blends (charges) in the form of calculations and laboratory analyses. Their tamping ability was also studied to determine the shearing force and density of the coal cake at different levels of moisture and grinding. The values of the bursting pressure of the developed coal blends were determined. It is shown that all of them are characterised by safe values of this indicator for coking. It is determined that the greatest influence on the value of the bursting pressure of the charge is exerted by the content of class <0.5 mm. The points of extremum (optimum) of the bursting pressure function obtained by differentiating the second-degree regression equation, in which the first-order derivative is zero, are given. The optimum range of coal charge moisture content, at which the tamping characteristics reach their maximum values, has been determined. It is shown that with a decrease in the yield of volatile substances, the value of tamping shifts to the upper limit, and vice versa. It was found that the charge with the highest amount of finely dispersed additives has the best tamping ability. Laboratory coking of the developed coal blends was carried out to evaluate the quality characteristics of the resulting cokes, the analysis of which allowed us to select the optimal compositions of coal blends. The cokes obtained from the blends characterised by the highest values of the tamping index were the best in terms of mechanical strength. It has been established that in terms of reactivity (CRI) and coke residue strength after reaction (CSR), all variants of the obtained coke have quite satisfactory values, given the unfavourable ratios of basic and acidic oxides in the chemical composition of ash. The paper presents and substantiates the calculation of the optimal height of coking chambers. Based on the obtained values of the strength of tamped briquettes σzz from the studied compositions, the height of the coking chambers should be 5.5 m. At the same time, the tamping ratio (cake height to its width) should be no more than 13. Keywords: tamping, coal cake, shear resistance, strength of the tamped cake, coke quality, height of the coking chamber. Corresponding author Miroshnichenko D.V, e-mail: dvmir79@gmail.com

Investigating the flow properties of bee pollen enriched milk powder during storage

Flow properties are necessary to select the right powder handling processes and design the industrial equipments for commercialization. The present study aims to investigate the particle size distribution and flow properties - cohesion, caking and powder flow speed dependency (PFSD) test, of spray-dried bee pollen enriched milk powder (packed in ALP, BOPP/LDPE, and PET/Al foil/LDPE) during storage at different temperatures (5, 25 and 40 °C) for 12 months. Cohesion, caking properties and compaction coefficients differed significantly (p < 0.05) according to storage period, temperature, and packaging materials. The powder samples had particle diameter (D50) ranging from 22.39 ± 0.16 to 157.48 ± 0.25 μm which increased abruptly after 6 months. Cohesion index showed the nearly easy flowing behavior of ALP packed powder (11.08 ± 0.10 to 14.67 ± 0.11 mm) stored at 5 and 25 °C. A decrease in column height ratio (1.00 ± 0.01 to 0.813 ± 0.011) and increase in cake height ratio (0.151 ± 0.009 to 0.558 ± 0.026) demonstrated the compressible behavior and susceptibility of powder to cake, respectively. PFSD test showed smaller values of compaction coefficient at higher speeds (10 mm/s and 100 mm/s) which established the free-flowing nature of powder samples at higher speeds. The findings of this work may foster processing and applications of bee pollen enriched milk powder in food industry.

An Ohmic heating study of the functionality of leavening acids in cream cake systems

Temperature gradients during cake baking complicate the study of leavening agent functionality, as leavening acid solubility and dissolution rate determine the moment of carbon dioxide (CO2) production. To control batter temperature, cream cake batter was baked in an electrical resistance oven (ERO). Simultaneously, CO2 release in the ERO headspace and cake height were monitored. Furthermore, CO2 production and release were linked to thermal transitions in the cake batter (DSC) and crumb structure setting (RVA). Early-acting organic acids produced high amounts of CO2 during mixing which could not be retained. This yielded low volume cakes. Sodium acid pyrophosphate and late-acting organic acids resulted in high quality cakes. However, CO2 production after crumb setting did not (further) improve cake quality, which implies suboptimal use of leavening power. This study highlights the importance of CO2 production during the early baking phase and illustrates the value of the ERO set-up for studying leavening agents.

Dewatering fine solid suspension by using steam pressure filtration

Steam pressure filtration is the combination of mechanical and thermal in one equipment. This process shows the advantages in comparison to conventional pressure filtration by the characteristic of its distinction mechanism. Application of steam pressure filtration can be listed: dewatering the suspension of fine solid, remove the contaminant, dangerous chemical, dissolved ions, protecting the human health as well as the environment. This paper shows the mechanism of steam pressure filtration as well as the result of tests, the comparison related to the efficiency between steam pressure filtration and conventional pressure filtration. The steam pressure filtration shows the high efficiency in mechanical displacement phase in both input parameters: solid volume fraction of suspension and the height of filter cake. The residual moisture content and saturation of filter cake using steam pressure filtration are lower 10÷20% than those values of filter cake using conventional pressure filtration. Moreover, some preliminary tests taking account to the drying phase of steam pressure filtration are also showed. The moisture of fine material filter cakes is around 6÷13%. Through the result of tests, interpretation and discussion, the application of steam pressure filtration is possible in the field of mineral processing and metallurgy.

Effects of inlet temperature and carrier concentration on spray-dried 'cempedak' (Artocarpus integer) fruit powder and its reconstitution properties.

'Cempedak' (Artocarpus integer) is an aromatic fruit which is similar to jackfruit. Although it is rich in vitamin A and is consumed fresh, the fruit has a short shelf life. Hence, it can be converted through a spray-drying process, to form powder, which is more stable. Powder flow properties are important when considering storage, while its reconstitution characteristics are critical for the consumer to make juice from the product. The parameters of spray-dried 'cempedak' fruit powder under study include inlet air temperature (140-180°C) and maltodextrin (DE 10) concentrations (5-15% w/w). Response surface methodology involving 14 runs was used to assess the effects of inlet temperature and maltodextrin on the powder flow properties and reconstitution properties of the spray-dried 'cempedak' powder. Out of the tested responses, only bulk density, change in cake height ratio, and water solubility index had a high coefficient of determination value. Inlet air temperature was found to be the main parameter to affect the bulk density, caking and water solubility index, when compared to maltodextrin concentration. By setting minimization of caking and maximization of water solubility index as the main determinants, the optimal parameters of 160°C inlet temperature and 15% (w/w) maltodextrin DE10 were generated, with a desirability of 0.697. The powder produced under optimal conditions (160°C and 15% w/w maltodextrin) had a low bulk density (480.01 kg/m3), low caking properties (0.17 change in cake height ratio), and a high solubility index (88.69). This indicates that the powder is stable to be stored (without caking) and will have good reconstitution when added to water.

Effects of inlet temperature and carrier concentration on spray-dried ‘cempedak’ (Artocarpus integer) fruit powder and its reconstitution properties [pdf

BACKGROUND 'Cempedak' (Artocarpus integer) is an aromatic fruit which is similar to jackfruit. Although it is rich in vitamin A and is consumed fresh, the fruit has a short shelf life. Hence, it can be converted through a spray-drying process, to form powder, which is more stable. Powder flow properties are important when considering storage, while its reconstitution characteristics are critical for the consumer to make juice from the product. METHODS The parameters of spray-dried 'cempedak' fruit powder under study include inlet air temperature (140-180°C) and maltodextrin (DE 10) concentrations (5-15% w/w). Response surface methodology involving 14 runs was used to assess the effects of inlet temperature and maltodextrin on the powder flow properties and reconstitution properties of the spray-dried 'cempedak' powder. RESULTS Out of the tested responses, only bulk density, change in cake height ratio, and water solubility index had a high coefficient of determination value. Inlet air temperature was found to be the main parameter to affect the bulk density, caking and water solubility index, when compared to maltodextrin concentration. By setting minimization of caking and maximization of water solubility index as the main determinants, the optimal parameters of 160°C inlet temperature and 15% (w/w) maltodextrin DE10 were generated, with a desirability of 0.697. CONCLUSIONS The powder produced under optimal conditions (160°C and 15% w/w maltodextrin) had a low bulk density (480.01 kg/m3), low caking properties (0.17 change in cake height ratio), and a high solubility index (88.69). This indicates that the powder is stable to be stored (without caking) and will have good reconstitution when added to water.

Investigating the effects of different cationic charge flocculation polymers on municipal wastewater sludge dewatering

Abstract The minimization of sludge produced by municipal wastewater treatment plants (MWWTPs) is critical as its handling accounts for approximately 50% of the total operating cost. The challenges in predicting dewatering performance can be overcome by optimizing the sludge treatment process, especially conditioning and dewatering. This study aimed to investigate sludge dewaterability at four different MWWTPs, using a gravity drainage test unit and a bench-scale press. The effect of differently treated effluent used as a solvent to mix the flocculation polymers was observed during dewatering. The membrane bioreactor (MBR) treated effluent yielded the highest filtrate volume in the lowest amount of time, with the least polymer flocculant dosage. The Box Behnken Design model fitted the data and proved a relationship between polymer dosage, cake solids concentration, and cake height during the bench-scale press tests.

Split-plot Central Composite Experimental Design Method for Optimization of Cake Height to Achieve desired Texture

In many industrial experimental situations, the levels of certain factors under investigation are much harder to change than others due to time and/or cost constraints. An appropriate approach to such situations is to restrict the randomization of the hard-to-change (HTC) factors, which leads to a split-plot structure. This work designs and conducts a split-plot central composite experiment for optimizing cake height using oven temperature(Factor A) as the HTC factor, amount of flour (B), baking powder (C), and amount of milk (D) as the easy-to-change (ETC) factors. A second-order split-plot central composite design (CCD) model was fit to the generated data and analyzed using generalized least squares (GLS). A stationary point, which gives optimum cake height, was then determined. The results show that main effects of oven temperature, flour, baking powder, and milk were highly significant on the cake height . Their quadratic effects were also significant except that of the flour. The flower/baking powder interaction effect was significant. The fitted model accounted for about 95% of the total variability in the cake height data. The observed optimum cake height was ̂ at a stationary point: A . This study has established the potentials of response surface experiments in optimizing products in food industries.&#x0D; Keywords: Experiment, split-plot CCD, Cake height, Design, Stationary point.

Anti-caking Agent Effects on the Properties of Spray-dried ‘Cempedak’ Fruit Powder

‘Cempedak’ fruit, an aromatic fruit that has a short shelf life can be converted into powder through spray-drying process. However, the spray-dried powder that was obtained had a high tendency to cake. Hence, three different anti-caking agents (calcium silicate, silicon dioxide, and calcium phosphate) were added separately at a concentration of 1.5% (w/w). It was found that calcium phosphate (1.5% w/w) yielded ‘cempedak’ fruit powder with lowest moisture content, water activity, hygroscopicity, and caking (change in cake height ratio), with minimal color changes in its reconstituted form and low viscosity. Different calcium phosphate concentration (0-2.00% w/w) was then applied in the production of ‘spray-dried’ powder. With increase of calcium phosphate addition from 0 to 0.66%, the moisture content, water activity, hygroscopicity, cake height ratio of ‘cempedak’ powder decreased, with no significant decrease with further addition. Calcium phosphate (0.66 % w/w) yielded powder with the best properties: lowest moisture content (4.65%), water activity (0.18), hygroscopicity (22.0), and change in cake height ratio (0.17). In addition, there was a minimal change in color of its reconstituted powder, with a slight change in viscosity.

Enhanced dewater efficiency for river sediment by top-to-bottom water transmitting channels with different materials.

Artificial top-to-bottom water transmitting channels made of threads of wool blend (WT), cotton (CT), flax (FT), and polyethylene (PET) were used to enhance the dewater efficiency for river sediment. In addition, the disordered channels composed of 3-mm-long WT segments mixed randomly into the river sediment were also employed. The most effective dewatering channels were found to be top-to-bottom WT channels with water absorption capacity of 8.7 ± 0.5 g · g-1 and volume compressibility of 2.94 ± 0.11. On the application of 0.1 MPa pressure to the mud surface, with initial water content of 60.0 ± 0.2 wt%, the water content obtained with channel material weight 0.411 wt% dry solids and channel to a mud cake height ratio of 0.95 upon 90-min dewatering was 39.6 ± 0.7 wt% with enhanced dewaterability, compared to that without channel addition, of 74.9 ± 0.9 kg · kg-1 · h-1. Using the same parameters, enhanced dewaterability was only 69.1 ± 0.3, 55.2 ± 2.8, and 9.1 ± 0.9 kg · kg-1 · h-1 for CT, FT, and PET channels, respectively. Moreover, the final water content of the mud cake dewatered in the presence of disordered WT channels at dosage 1.10 wt% was 49.8 ± 0.7 wt% with enhanced dewaterability of 5.9 ± 0.5 kg · kg-1 · h-1 only. These demonstrate that the compressibility of the water transmitting material is the main factor affecting dewatering efficiency with the water absorption capacity also being important.

Steam pressure filtration in combination with a water insoluble pore liquid

The treatment of solvent-loaded solids, e.g. following a solid–liquid extraction presents a challenge in practice becoming even more complicated if solvents used are volatile organic compounds (VOC) which are poorly water soluble and thus bio-incompatible. A complete mechanical separation of the VOC from solids is not possible and following drying processes are usually energy intensive.Steam pressure filtration provides an efficient alternative combining mechanical and thermal treatment of filter cakes by using steam resulting in excellent washing and dewatering behaviour of the filter cake. A subsequent steam stripping offers a further reduction of the VOC load, which was not part of comprehensive investigations yet.The overarching goal of this paper is to expand understanding of steam pressure filtration in combination with water insoluble VOC. Furthermore, it is shown that a complete purification of the solids by steam stripping is possible with only low steam consumption at moderate filter cake heights.

Formulasi Campuran Bahan Pengemulsi untuk Bolu Sponge

To make a sponge cake, a mix of emulsifiers provides an improved aeration. The aim of this research was to formulate the mix of distilled monoglycerides (DMG) and polyglycerol esters (PGE), which had yellowish color, in a gel form for its application in sponge cake. The formula of the gel consists of primary and secondary food additives: 15.3% DMG, 6.5% PGE, 25.8% other emulsifiers and carrier including colorings (ponceau and tartrazine), 26.1% sorbitol, and 26.3% water. DMG and PGE had different colors from their expected standard color, white. The formula of DMG (15.3%) and PGE (6.5%) mix, comprising 21.8% of the formula above, was re-formulated by 100:0, 75:25, 50:50, 25:75, and 0:100 ratios of DMG to PGE. The physical characteristics of the formula consisting of color characteristic by chromameter, sensory score by R-Index method and gel spreadability were compared to the formula using standard materials of DMG and PGE. The formula was then applied for sponge cake. The specific gravity of sponge cake batter, height of sponge cake after baking, as well as sensory characteristics of crumb structure and crumb color of sponge cake were analyzed. The results of physical characterization of formula revealed that the use of 100% of PGE and the use of DMG up to 50% did not significantly differ from the standard formula. The combination of DMG and PGE formula did not affect batter specific gravity, cake height and crumb structure, but affected color of the crumb.

Analysis of wastewater sludge drying process in vacuum filters

The paper presents a case study on wastewater sludge drying in a vacuum filter. Using finite element analysis it is estimated the variation with cake height, along its centerline, of temperature, liquid and gaseous phase ratios. Numerical results are estimated after 30 hours of drying at different temperatures (60°C, 80°C and 100°C), considering a sludge initial moisture content of 20%.

Study on the influence of solids volume fraction on filter cake structures using micro tomography

Prediction of micro processes, filter cake build-up and porous media flow is a key challenge to describe macroscopic parameters like filter cake resistance. This is based on a precise description, not only of the disperse solid fraction, but the distributed properties of the voids between the particles. Lab-experiments are carried out with alumina and limestone, which differ in particle size distribution (PSD) and resulting filter cake structure. Filter cakes of both materials are characterized by standardized lab tests and additionally, alumina cakes are measured with X-ray microscopy (XRM). Focusing on distributed process key parameters, the data gives a deeper understanding of the laboratory experiments.The solid volume fraction inside the feed strongly influences the particle sedimentation and leads typically to a top layer formation of fine particles in the final filter cake, which has a negative influence on subsequent process steps. The top layers seal the filter cake for washing liquid and increase the capillary entry pressure for gas differential pressure de-watering. The influence on cake structure can be seen in a change of porosity, particle size and shape distribution over the height of the filter cake. In all measurements, homogenous filter cake structures could only be achieved by increasing the solid volume fraction inside the suspension above a certain percentage, at which particle size related sedimentation effects could be neglected and only zone sedimentation occurred. XRM offers the chance to quantify these effects, which previously could only be described qualitatively.

Investigation of Plastering Effect in Casing-while-Drilling – A CFD Study

In conventional oil and gas well drilling, filter cake builds up on the wellbore wall due to overbalance pressure which forces the drilling fluid into the rock formation and leaves solid particles on the wellbore wall. The presence of a filter cake is beneficial since it reduces fluid loss and damage to the formation. Plastering or “smearing” effect is a mechanical conditioning of a wellbore which is believed to enhance wellbore stability by packing any fractured zone with drilled-cuttings and fluid. This phenomenon is usually believed to occur in a narrow annular wellbore such as casing-while-drilling (CwD), where actual casing is used to drill and transmit both mechanical and hydraulic energy to the bit, rather than the usual conventional drillstring. In this study, a three-dimensional modelling and numerical simulation is carried out to examine the influence of particle size (drilled cuttings size) of 100 microns to 2000 microns and fluid type (water, oil-based mud, and water-based mud) on filter cake formation in a vertical wellbore. The simulation adopts the inhomogeneous Eulerian-Eulerian two-fluid model to solve the two-phase flow equations. The numerical model was set up to depict the subsurface conditions at moderate pressure and temperature of 13.8 MPa and 30°C respectively. The results showed that with the increase in particle size, the filter cake height increased marginally for all fluid types, where the percentage increment ranges from 1.3% to 2.6%. Furthermore, filter cake thickness was high when water was used as the drilling fluid, whereas, the least filter cake height was recorded when oil-based mud was used. The filter cake formation on the vertical wellbore was therefore non-uniform for all scenarios. This study shows how useful numerical simulation can capture the physical mechanisms affecting plastering effect and optimise drilling parameters during casing-while drilling.

Determination of filtration and consolidation properties of protein crystal suspensions using analytical photocentrifuges with low volume samples

Proteins and in particular pharmaceutical proteins like monoclonal antibodies are expensive products. Protein crystallization is an interesting alternative process step to the common purification and formulation of such proteins. The solid-liquid separation of proteins however, is a challenging task because the proteins are sensitive to mechanical stress, which could lead to crystal breakage and often are only available in small amounts for research and development. In this study a newly developed filtration cell for the LUMiSizer® centrifuge is used to analyze the filtration behavior with low volume samples. Isometric and needle shaped lysozyme crystals serve as model protein crystals. The needle shaped crystals showed about twice as high compressibility and much higher cake resistance than the isometric lysozyme crystals. After the filtration at maximum pressure in the centrifuge the mean particle diameter decreased compared to the unstressed median diameter. With the filtration cell the cake height and filter cake compression can be monitored in situ and the filter cake resistance and solids volume fraction can be calculated with one experiment using 200–300 μl sample.