Rotary Dryer Research Articles

Spreading process simulation and optimization of the flight of municipal sludge rotary dryer

In view of flights spreading process of municipal sludge rotary dryer, the holding capacity and spreading model of flights during sludge drum dryer rotation were established, the influence of setting angle and type of flights on flights tilting angle and material spreading uniformity were investigated through MATLAB programming simulation, and then the structure of flights were optimized. It can be found that the order from large to small of tilting angle of different flight types is arc type, bending type and one-section type, the spreading sludge granules uniformity of bending type flight is better than those of one-section and arc type flight, the hinge connecting part of improved flight can ensure the sludge grabbed, and solve outlet difficult problem of sludge granules at the inlet.

ACCELERATED DRYING AND STABILIZATION OF CANOLA SEEDS AND OIL

A study was carried out to evaluate the effect of accelerated drying on seeds moisture content and stabilization the extracted oil using a conduction heating rotary dryer. the drying temperatures were set at approximately(85,95,105,115,125,135, and 145oc) and the drying times were set at (3,6,9,12,15, and18 min) and the moisture contents of canola seeds was (21%-27%-31%). The results showed that all the drying processes on the falling rat period in which the rate of evaporation tends to fall as the moisture content decreases and the drying curve decays exponentially towards the equilibrium moisture content. Rapid moisture removal from seeds was obvious in all experiments particularity at higher heating surface temperature and longer exposure time .The result also showed that both the simple and the modified exponential equation models were satisfactorily described the drying behavior of canola seeds and predicted the change in seeds moisture contents indicated by lower values of standard error of estimate (SE) and the higher coefficient of determination(R2).Meanwhile ,high temperature conduction heating the extracted canola oil was stabilized as reeducated from the lower values of free fatty acids of the samples stored under room temperature. In general, it can be said that ,the accelerated drying and heat stabilization of canola seeds using the conduction heating rotary dryer may be considered as an effective procedure for moisture ,and oil stabilization.

Physicochemical and Rheological Properties of Sago (MetroxylonSagu) Starch Modified with Lactic Acid Hydrolysis and UV Rotary Drying

Modification of sago starch using acid hydrolysis will change some physicochemical and rheological properties. Sago is easy to grow in tropical areas of coastal areas, many found in eastern Indonesia has a simple ergonomic terms. Ingredients of sago starch is consist of 20-30% amylose and 70-80% amylopectin which make sago starch difficult to dissolve in cold water, easy to gelatinize, high viscosity, hard and not expands in baking process. This study will analyse modified sago using lactic acid hydrolysis method and use UV rotary drying for 20 minutes. The properties of modified sago starch were observed i.e. pH, density, solubility, swelling power, and baking expansion. Time variables hydrolysis is 10; 15; 20; 25; and 30 minutes with a rotation speed of 8 rpm at room temperature. The results showed that the solubility, swelling power and baking expansion was increase. The density results showed that the longer acid hydrolysis time can make the smaller in the density. Solubility and swelling power showed increasing significantly compared to native sago starch. Modification by using UV light changes significantly the properties characteristics of product.

On-Line Microwave Moisture Technique Performance of Ferronickel

The competency of observing continuous record of water content or moisture of minerals, then control it in actual real-time basis is crucial that will affects mineral ore quality, cohesivity, process control, material handling and flowability. This paper describes experiment of a Random Stratified Sampling Sweeping Microwave method, moisture content measurement technique that lessen interference, annulling or superimposing signal, that are normal deviations in moisture measurement using microwave transmission method. The technique is used for ferronickel ore running on a belt conveyor exit to the rotary dryer. It showed that high bed depth and high phase stability are essential requirements that must be achieved for successful microwave moisture measurement analysis of ferronickel ore. Attenuation parameter was the suitable parameter for the experiment, instead of Phase parameter, which is common parameter for the ferronickel application. The experimental results revealed accuracy of 0.78wt%, standard error of 0.18 and regression of 0.73.

Convective sludge drying by rotary drum dryer using waste steam for palm oil mill effluent treatment

Abstract Achieving a more sustainable wastewater treatment plant has never been so important. Issues around energy consumption and pollutants removal efficiency are of growing importance in the context of production costs and pollution control. In the palm oil industry, more than 85% mills are managing their palm oil mill effluent (POME) via lagoons, yet the system considered less effective as the quality of the effluent hardly achieved the permissible limits. It is therefore in the best interest of the industry to employ a better practice. Convective sludge drying (CSD) has been shown to have exceptional efficiency in high-strength wastewater treatment. In this study, CSD epitomized the zero-emission of POME treatment due to the fact that; 1) It operates on low-grade steam discharged by the mill instead of electricity, leading to a huge cut on energy consumption, 2) Production of secondary micronutrients-enriched solids by-product (i.e., calcium and magnesium) that can be repurposed as fertilizer, and 3) The decoction produced can potentially be reused to irrigate the existing oil palm plantation for nutrient cycling. The treatment resulted in substantial removal of the chemical oxygen demand (COD), biological oxygen demand (BOD), suspended solids (SS), ammoniacal nitrogen (AN), and oil and grease (OG) down to 2 mg/L, 67.7 mg/L, 40.0 mg/L, 99% of BOD, COD, SS, OG, and AN removal efficiency. The operating cost was valued at USD 1.91 per m3 POME. The pilot-scale operation proved CSD is a viable alternative to the lagoons.

Numerical simulation of the flow of agricultural seeds inside a rotary drum dryer by DEM

Drying agricultural seeds is a commonly used industrial process. The drying process of the material inside the rotary drum is directly related to the seed movement in the dryer. However, the movement of agricultural seeds inside the rotary drum dryer has never seriously been studied before. This paper adopts a mathematical model for simulating particle flow in rotary drum dryers for agricultural seeds using discrete element methods (DEMs). It is aimed to study the efficiency of the rotary drum dryer and how this is linked to the type and number of vans and positions of vans mounted inside the rotary drum dryer. The study parameters were performed by varying the rotational speed, inclination of the rotary drum installation with minimal impact on the flow of seeds, and segregation of the seeds in a rotary drum dryer. The simulation results show that different operating conditions were the most significant influences on the movement of seeds. Maximum height of the particle falling can be realized when the rotary drums are operating at an optimum condition for particle loading from the bottom drum.

Drying efficiency and product quality of biomass drying: a review

Drying is an energy-intensive pretreatment process of biomass for production of biofuels by thermo-chemical conversion. The efficiency and quality during biomass drying have a significant impact on the economy and sustainability of bioenergy plants. In this review, recent development of conventional dryers, including rotary drum dryer, fluidized bed dryer, pneumatic dryer, agitated drum dryer and fixed or moving bed dryer were described. Progress in the study of advanced drying technologies, such as solar drying, microwave-drying and far-infrared drying in laboratory and pilot-plant scale were summarized as well. In order to reduce the energy consumption of drying system, multistage drying, self-heat recuperation and process integration were introduced in the bioenergy plant. Theoretical performance of these energy-saving processes is represented in this review, along with some experimental findings in the pilot plants.

METODE PENGERINGAN AMPAS TEBU (BAGASSE) DENGAN PEMANFAATAN KEMBALI PANAS GAS BUANG BOILER DI PG. PRADJEKAN BONDOWOSO

At present the need for fossil fuels is very high, while reserves in nature are decreasing. For this reason, innovation is needed to find alternative energy from fossil fuels to alternative energy that is more environmentally friendly and can be renewed. The sugar factory as one of the Dutch heritage industries that produces solid waste in the form of bagasse can be used for boiler fuel. While the boiler exhaust gas (flue gas) from the chimney generated from burning fuel also causes air pollution can be used for drying bagasse so as to reduce the impact of pollution caused by the exhaust gas. The use of bagasse with a moisture content of around 49-52% as boiler fuel as one of the causes of burning in the combustion chamber is not perfect and causes air pollution. The high temperature of the smoke gas coming out through the boiler chimney around 220 C has a heat content of 13475.72 kW and still high levels of water in the pulp can certainly be used to dry bagasse using a dryer (Rotary Dryer) Through the use of flue gas that is wasted on the boiler chimney for bagasse drying, it can increase the heat value of bagasse 50,544 x 106 Kcal / hour for the production of bagasse 30 tons / hour, reduce bagasse water content up to 35,1%, increase thermal efficiency and reduce pollutants released into the surrounding environment.

Content of Heavy Metals in Soil and in Pineapple Fertilized With Sewage Sludge

The usage of sewage sludge in agriculture can increase the levels of heavy metals in the soil, compromising their use as fertilizer. The objective of this study was to evaluate the contamination of soil and pineapple by heavy metals after the application of treated sewage sludge by different forms in three orders of soils under greenhouse conditions. The treatments, in a factorial scheme 7 × 3 were distributed in a randomized complete block design with three replications, corresponding to seven fertilization management: soil without fertilization, chemical fertilization, fertilization with composted sludge sewage, fertilization with vermicompost sewage sludge, fertilization with solarized sewage sludge, fertilization as sewage sludge dried in a Bruthus-Albrecht rotary sludge dryer and fertilization with limed sludge sewage, combined with three orders of soils: Cambisol, Nitisol and Acrisol. The Zn, Cu, Cr, Pb, Ba, Cd, Ni, As and Se contents were analyzed in the soil, in the leaf of greater length (D leaf) and in the fruit pulp of the pineapple. The Acrisol provided more favorable conditions to the increase in the availability and absorption of Pb and As by D leaf and fruit of the pineapple. Fertilization with composted, vermicompost and solarized sewage sludge provided high levels of Pb, As, Zn in leaf D and in the pineapple fruit, relating the interference of sludge stabilization process with the absorption of metals by pineapple fruits.

PEMBUATAN ALAT PENGERING BERPUTAR (ROTARY) KOPI DAN LADA HITAM MENGGUNAKAN MIKROKONTROLER ARDUINO UNO DESA AIR RAMAN KABUPATEN KEPAHIANG PROPINSI BENGKULU

Bengkulu Province has many potentials such as beaches, conservation forests, plantations and others. Plantations in Bengkulu consist of smallholders and private / BUMN businesses. Smallholder plantations include coffee, black pepper, palm, rubber, areca nut and other gardens. The results of this plantation are still traditionally processed, which is drying and drying in the open with the help of solar heat. This drying process is still being implemented where the quality is poorly controlled. This has caused the yield of the plantation in Bengkulu to be unknown to other regions. like coffee in the Bengkulu area which has a distinctive taste characteristic compared to other regions. Coffee that is processed is Robusta or Arabica coffee which is the mainstay of the people of Air Raman Village, Bengkulu Province. The processing process is dried in the yard of the house, field, roadside and others. This drying and processing process is easily polluted from dust, animal waste, uneven drying. And the erratic drying time causes the villagers to need a machine or garden processing technology. One technology is a rotary dryer. Rotary drying machines can be used by utilizing regional potential such as solar energy, wind energy, water energy and others. In addition to Coffee, this village also has garden products such as black pepper, Pinang and others where the process is the same as the coffee harvest. The advantage of this dryer is a shorter drying time, the use of solar energy can minimize operational costs for drying coffee and black pepper. The dried coffee and black pepper are free from animal waste, dust and various other types of garbage and the process of drying more than 4 days from drying is done manually / in the public yard. This is because the temperature inside the drying machine is rotary higher than the open air, the level of dryness of coffee and black pepper is produced evenly, because the temperature in the rotary dryer is equipped with a stirrer evenly spread so that the stirring process is no longer necessary. . The working mechanism of this tool is expected to help people producing coffee and black pepper to dry their crops so that the quality of coffee and black pepper is good and the selling value is high. The output of PPM activities The application of science and technology is a high selling value that will increase people's income, improve people's welfare to be better and also create new jobs for the community as a producer of rotary drying machines. The availability of appropriate technology for the design and construction of rotary drying machines. Scientific publications at the national level are published in the national journal Dharma Raflesia December 2018

Drying characteristic of unhulled rice in biomass energy and combination rotary dryer

Drying of agricultural products aimed to extend the shelf life. The moisture content of the unhulled rice must be lowered to a limit of 14% to be able to maintain the quality and avoid post-harvest damage. Ciherang variety unhulled rice has been dried using biomass energy rotary dryer and biomass-heater combination for 180 minutes. In this study, several drying characteristics of unhulled rice have been analyzed including the determination of water content and the drying rate. The exponential equation illustrated the relationship between the unhulled rice water content (%) and the drying time (minutes), MC = 23.279 e−0.002t and MC = 27.255 e−0.004t respectively for the stage 1 decline drying rate in biomass energy and combination, while at the decline drying rate stage 2 found MC = 22.209 e−0.002t and MC = 27.576 e−0.004t respectively in biomass energy and combination. The relationship between unhulled rice drying rate (dM/dt) and drying time (minutes) was illustrated by the exponential equation v = 0.0466 e−0.002t and v = 0.109 e−0.004t respectively for the decline drying rate stage 1 in biomass energy and combination while at the decline drying rate stage 2, v = 0.0444 e−0.002t and v = 0.0775 e−0.003t respectively in biomass energy and combination.

Finite Element Method Analysis for Manufacturing Design Drum Dryer of Rotary Dryer Machine

Component rotary dryer machine has been made by forming and casting process such as drum dryer. Forming process of drum dryer by rolling, welding and finishing. Using the casting process for product of drum dryer is important to know design shape, material and dimension. Before manufacturing process of drum dryer, design drum dryer can be made by using finite element method (FEM) analyse. FEM can solve the problem of design drum easily and cheaper. In this paper focus on the design of drum dryer by using FEM analyse. The value of maximum stress is obtained by variant shape, thickness and material. Steel and stainless steel is applied for material drum. The result shows that maximum stress of drum dryer is 244 MPa for 5 mm thickness and steel material and 267 MPa for 10 mm of thickness. For stainless steel, maximum stress at drum dryer is 167 MPa for thickness 5 mm and 182 MPa for thickness 10 mm. Material drum dryer for rotary dryer machine to liquid waste processing is suitable made by stainless steel.

Wood Chip Drying through the Using of a Mobile Rotary Dryer

Drying is a critical point for the exploitation of biomass for energy production. High moisture content negatively affects the efficiency of power generation in combustion and gasification systems. Different types of dryers are available however; it is known that rotary dryers have low cost of maintenance and consume 15% and 30% less in terms of specific energy. The study analyzed the drying process of woody residues using a new prototype of mobile rotary dryer cocurrent flow. Woodchip of poplar (Populus spp.), black locust (Robinia pseudoacacia L.), and grapevine (Vitis vinifera L.) pruning were dried in a rotary drier. The drying cycle lasted 8 h for poplar, 6 h for black locust, and 6 h for pruning of grapevine. The initial biomass had a moisture content of around 50% for the poplar and around 30% for grapevine and black locust. The study showed that some characteristics of the biomass (e.g., initial moisture content, particle size distribution, bulk density) influence the technical parameters (i.e., airflow temperature, rate, and speed) of the drying process and, hence, the energy demand. At the end of the drying process, 17% of water was removed for poplar wood chips and 31% for grapevine and black locust wood chips. To achieve this, result the three-biomass required 1.61 (poplar), 0.86 (grapevine), and 1.12 MJ kgdry solids−1 (black locust), with an efficiency of thermal drying (η) respectively of 37%, 12%, and 27%. In the future, the results obtained suggest an increase in the efficiency of the thermal insulation of the mobile dryer, and the application of the mobile dryer in a small farm, for the recovery of exhaust gases from thermal power plants.

Wood Chip Drying through the Using of a Mobile Rotary Dryer

Wood Chip Drying through the Using of a Mobile Rotary Dryer

Dehydration of microalgae Spirulina platensis in a rotary drum with inert bed

Among the various species of microalgae, Spirulina platensis has recently attracted attention from food and pharmaceutical industries due to its high contents of protein and bioactive compounds. Due to its high moisture content, a major challenge in the use of this microalga is its perishability. In this work, we investigated the use of a non-conventional rotary dryer (with an inert bed) for drying microalga Spirulina platensis. We quantified the effects of air temperature, feed rate, rotation speed, and filling degree of the inert particles on process performance. We then performed an optimization study using the Differential Evolution algorithm to identify the operating conditions that maximize process yield. We also performed a DEM simulation to gain a better understanding of the fluid dynamics. The results prove that this non-conventional system offers an interesting alternative for expanding use of this biomass, when performed under appropriate operating conditions.

Experimental study on drying characteristic of corncob in plate rotary heat exchanger

AbstractAgricultural processing residues, such as corncobs, can be used as good biomass pellet fuels. To thoroughly study the drying characteristics of corncobs in a rotary dryer, a plate rotary heat exchanger (PRHE) was applied to the drying of corncob particles in the present article. The PRHE had an inner diameter of 273 mm and a length of 1,000 mm. Twelve rectangular plates were designed as the heating plate. The influence of several parameters on the corncob drying characteristics was experimentally investigated. The results indicated that the drying rate increased with increasing corncob initial moisture content, increasing dryer heating power, and decreasing corncob particle diameter. Then, based on the experimental results, two exponential correlations were regressed by the least squares method. Both the correlations were valid and the three‐parameter model had a better fitting degree than the two‐parameter model. The trend in the drying rate of corncobs in PRHE clearly included a rising‐rate stage and a falling‐rate stage. The Taguchi approach was employed to study the impact degree of different factors on the maximum drying rate, which showed that initial moisture content had the largest impact degree, followed by heating power; furthermore, the effect of particle diameter was not significant.Practical applicationsPromoting the use of biomass energy is an effective means to respond to the climate change challenge. As one of the major agricultural processing residues in mainland China, corncob can be processed into biomass pellet fuels with easy storage, high energy density, and low pollutant emissions after crushing, drying and compression molding. For the sake of settling the uncontrollable limitations of traditional open air‐drying method for corncob, author developed a new type of plate rotary heat exchanger (PRHE). By investigating the drying characteristics of corncob in PRHE with various experimental conditions, research findings provide references for the development and large‐scale industrial application of plate rotary drying technology in the drying of agricultural processing residues in the future.

Experimental Analysis of Brewers’ Spent Grains Steam Gasification in an Allothermal Batch Reactor

In this work, brewers’ spent grains (BSG) were evaluated and studied in order to obtain a combustible gas by means of allothermal steam gasification. BSG were preprocessed in a rotary dryer and a pelletizer prior to gasification in an indirectly heated batch reactor. BSG characterization was conducted by means of proximate, ultimate, and thermogravimetric analysis, allowing us to conclude that BSG have characteristics comparable to those of regular lignocellulosic biomasses. Gasification tests were performed in an allothermal bench-scale batch reactor in order to determine the effect of temperature and steam-to-biomass ratio (S/B) in the produced gas. The produced gas was mainly composed of 22.8–30.2% H2, 15.1–22.3% CO, and 7.2–11.1% CH4, contributing to a heating value of 8.11–9.0 MJ/Nm3 with the higher values found for a low S/B ratio and for high temperatures. The performance of the process was assessed by evaluating the cold gas and carbon conversion efficiencies. These indicators were found to be in the ranges 47.0%–52.1% and 57.0%–62.7%, respectively. The main conclusion of this work is that the produced gas obtained from BSG steam gasification has sufficient quality to open other options to beer producers to use their own brewing wastes to satisfy their energy needs, allowing them to progress toward the circular economy concept.

Granular transport through flighted rotary drums operated at optimum-loading: Mathematical model

This paper discusses the transport of granular materials through flighted rotary drums operated at the optimum loading. A mathematical model is derived from the force balance acting on a single traveling particle, to predict the mean residence time of transportation. Based on the available parameters of mean height of falling curtains and final discharge angle, this model can be helpful to estimate the appropriate solid feeding rate. Two steps were followed to implement the use of the model. Firstly, experiments were carried out on a batch rotary drum to obtain the needed input parameters. Then, a case study of a small capacity rotary dryer was considered. In both steps, the drum was operated at the optimum loading. The model results were compared with other correlation from the literature for two cases of solid and air flows: con-current and counter current. Based on the results, a factor is introduced for generalized correlation from literature.

CFD Analysis of Temperature Drying Chamber at Rotary Dryer With Combined Energy

A heat and mass transfer model has been developed using Computation Fluid Dynamics (CFD) to see the pattern of hot air flow, in the drying chamber in the rotary dryer. During the experiment parameters used as input data on CFD are air flow velocity and temperature drying in experimental measurements in the range of 1 hour, 2 hours and 3 hours. CFD analysis results show the uneven distribution of heat in the drying chamber in a variation of 1 hour and 2 hours. The CFD contour indicates that heat only spreads to the top and center of the drying chamber. The average temperature of the top of the drying chamber is 51,75°C, while at the bottom is 45,19°C. The simulation results on 3 hours of drying showed that the contour of hot air spread fairly evenly in the drying chamber with an average drying room temperature of 46,3°C. The air flow rate and air velocity in the drying chamber are quite constant with an average of 3,3 m/s.

Comparative life cycle assessment of ornamental stone processing waste recycling, sand, clay and limestone filler.

Owing to the cost of destination and transportation of ornamental stone processing waste, many studies focused on the reuse and recycling of this product. However, there is a scarcity of articles addressing the environmental viability of the recycling of ornamental stone. In this context, this study comprehends a comparative life cycle assessment of ornamental stone processing waste and conventional materials: sand, clay and limestone filler. The modelling software used was SimaPro 8.3.0.0 with Ecoinvent 3.2 database, employing the ReCiPe H/H methodology for impact assessment. The results show that the recycling of ornamental stone processing waste is environmentally preferable, and the artificial drying alternatives, such as flash dryer and rotary dryer, have lower environmental impact than extracting and processing clay through atomisation methods and limestone filler production. The sensitivity analysis indicated that it is possible to transport the ornamental stone processing waste 37 km after processing, so it reaches the same environmental impact as sand extracted by dredging. On the other hand, an increase of 25% in the energy consumption incremented only 7% of the environmental impact owing to the Brazilian energy mix.