Drying Unit Research Articles

Advanced exergoenvironmental analysis of the oil shale retorting process with SJ-type rectangular retort

A framework integrated the advanced exergy analysis with the theory of life cycle assessment is constructed to evaluate and optimize the environmental performance of energy conversion systems. The SJ-type oil shale retorting (SJ-OSR) process as one of the energy conversion systems with severe environmental pollution is employed to demonstrate the feasibility of the proposed approach. The results show that the avoidable exergy destruction of the retorting unit and recycle gas combustion unit to their total exergy destruction are 56.49% and 65.12%, respectively. The environmental impact for the total exergy destruction (BD,tot) of the SJ-OSR process is 1219.05 mPts/s. The environmental impact for total endogenous exergy destruction is 984.63 mPts/s, which accounts for 80.77% of the BD,tot. As for the drying, retorting and recycle gas combustion units, their environmental impacts related to avoidable exergy destruction rates are larger than the unavoidable parts. Most of the environmental impact with respect to the avoidable exergy destruction rates is endogenous (350.22 mPts/s). Based on the proposed two improvement strategies, ultimately, the BD,tot of the improved process decreases obviously from 1219.05 mPts/s to 1037.87 mPts/s, and the proportion of BD,tot reduced is about 14.86% of that for the existing process.

Techno-economic analysis and life cycle assessment of microwave co-pyrolysis of food waste and low-density polyethylene

This paper presents a techno-economic analysis (TEA) and life cycle assessment (LCA) of microwave (MW) co-pyrolysis of comingled food waste (FW). Lab scale (capacity- 1 kg/d) MW co-pyrolysis studies of FW and low-density polyethylene (LDPE) yielded 42 wt.% of bio-oil, 42 wt.% of biochar and 16 wt.% of pygas. The fixed and monthly operating cost of the lab scale MW co-pyrolysis reactor was 10,00,000 INR/kg and 8,248 INR/kg, respectively. The respective cost of a commercial MW co-pyrolysis plant (capacity-100 kg/d) was estimated as 53,12,585 INR/kg and 24,420 INR/kg. It was estimated that with 7 % of the internal rate of recovery (IRR), the breakeven point would be achieved within 4 years. The LCA of the commercial MW co-pyrolysis plant evaluated that the drying and pyrolysis unit consumed 91 % of total energy and contributed most to environmental impact. Thus, emission of 38.92 kg CO2 eq, 48.00*10-3 kg SO2 eq, 7.70*10-3 kg PO4-3 eq, 1100.10*10-3 kg dichlorobenzene (DCB) eq and 3.50*10-3 kg C2H6 was projected for MW co-pyrolysis of 100 kg FW and LDPE. Overall, TEA and LCA suggested that the commercial MAP plant would provide higher conversion efficiency, lower energy consumption (0.54 kWh/kg) and environmental risk with an attractive economic return by selling bio-oil + biochar at the rate of 40 INR/kg.

Experimental investigation and drying kinetics of mixed type solar dryer with thermal energy storage material for drying of apple slices

ABSTRACT The current study covers drying of 500 g of apple slices of uniform thickness by forced convection mixed solar drying unit integrated with paraffin wax and natural sand as energy storage (thermal) material. The experimental setup consists of solar collector (for heating inlet air) and drying chamber in which heated air removes moisture content of apple slices from 80 to 21.7% (wet basis) in 3.5 h during April 2021. The average moisture diffusivity for lower tray was 1.018 × 10−8 m2/s which was 16.3% and 28.6% greater than upper tray and open sun drying, respectively. The average drying rate for lower tray (0.5318 kg water/kg dried product/h) was higher than upper tray and open sun drying. At the same drying time of 3.5 h, the final moisture content in lower tray, upper tray and open sun drying were obtained as 21.7%, 22.64% and 25.61%, respectively, which indicates that present solar drying is better than open sun drying. The average drying exergy efficiency was obtained as 48.14% with maximum value as 74%. The maximum (& average) drying efficiency and collector efficiency were 13% (& 5.56%) and 83.3% (& 66.39%), respectively. Wang and Singh model was found the best suitable among 14 thin layer drying models.

Design features of technological functional components of stationary automobile gas filling compressor stations (CNG stations). Part 2

The characteristics and parameters of the main technological functional components and systems of CNG filling stations are given. The composition and characteristics of CNG filling station systems and units are given. The analysis of the technical and operational characteristics of the technological components of the CNG filling station is given. The characteristics of the inlet cranes and the gas flow metering system are given. The basic technological scheme of the preliminary gas purification system is given. The requirements for the process equipment and functional systems of the CNG filling station are set out. The design and technological scheme of the gas adsorber and accumulator is given. A schematic diagram of the main components of a reciprocating compressor is given. The characteristics and the principle of operation of the shut-off and safety equipment of the CNG filling station are given. A schematic diagram of gas drying and purification is given. A schematic diagram of the refueling module and the means of ensuring the safety of its operation is shown. Keywords compressed natural gas, technological and functional components of CNG filling stations, input crane unit, gas metering unit, gas pretreatment unit, gas drying and purification unit, gas compression unit, gas accumulator unit, gas filling column

Design features of technological functional components of stationary automobile gas filling compressor stations (CNG stations). Part 1

The characteristics and parameters of the main technological functional components and systems of CNG filling stations are given. The composition and characteristics of CNG filling station systems and units are given. The analysis of the technical and operational characteristics of the technological components of the CNG filling station is given. The characteristics of the inlet cranes and the gas flow metering system are given. The basic technological scheme of the preliminary gas purification system is given. The requirements for the process equipment and functional systems of the CNG filling station are set out. The design and technological scheme of the gas adsorber and accumulator is given. A schematic diagram of the main components of a reciprocating compressor is given. The characteristics and the principle of operation of the shut-off and safety equipment of the CNG filling station are given. A schematic diagram of gas drying and purification is given. A schematic diagram of the refueling module and the means of ensuring the safety of its operation is shown. Keywords compressed natural gas, technological and functional components of CNG filling stations, input crane unit, gas metering unit, gas pretreatment unit, gas drying and purification unit, gas compression unit, gas accumulator unit, gas filling column

Innovative Drying and Cleaning Unit for the Modernization of the Technology of Primary Processing of Cotton

Innovative Drying and Cleaning Unit for the Modernization of the Technology of Primary Processing of Cotton

Energy, Exergy, and Advanced Exergy Analysis of a Cogeneration System Combined with a Drying Unit of Phosphate Fertilizers

Energy, Exergy, and Advanced Exergy Analysis of a Cogeneration System Combined with a Drying Unit of Phosphate Fertilizers

Дослідження термічної підготовки ковшів

The purpose of the work is to develop a computer model of ladle heating with an open torch on a drying and high-temperature heating installation to control the thermal preparation process. The task of managing ladle drying and high-temperature heating installations (USVR) is to implement their operating modes, which ensure obtaining the specified temperature profile of the lining layers of steel castings with minimal fuel consumption. The task of controlling by drying and high-temperature heating unit (SHHS) is to implement their operating modes that provide a given temperature profile of steel pouring ladle lining layers with minimal fuel consumption. Since modern technical means of control do not allow obtaining relevant information about the temperature field of the lining of the walls and bottom of the ladle, it is necessary to create a predictive model of its heating by an open torch at the SHHS. A 68-ton rammed steel-pouring ladle KС-68 was chosen as the object of study. According to the research data, the shape and dimensions of the open torch were evaluated at OCC PrJSC “Evraz- Dnipro Metallurgical Plant”. A digital camera recorded the torch at the burner outlet at a natural gas flow rate of 50 m3/h, which corresponds to the standard mode of drying and warming up the ladle. For modeling purposes, the resulting torch shape was approximated by two truncated cones. Determination of the parameters of convective-radiant heat transfer in the “torch – cover – wall – ladle bottom” system was carried out taking into account the temperature of the torch, the thermophysical properties of the lining materials, as well as the irradiance coefficients and the emissivity of the surfaces. The calculation of the temperature field in the lining of the wall and bottom of the ladle was carried out by the finite element method implemented in the ANSYS package. Based on the simulation, a change in the temperature field of the ladle lining was obtained during its heating at the SHHS with an open torch for 6 hours, which corresponds to the current technology. An analysis of the dynamics of the temperature field of the ladle lining obtained as a result of modeling indicates that when it is heated by an open torch at a drying and high-temperature heating unit, thermal stresses do not occur, which are dangerous from the point of view of cracking in the layers of refractory materials. The maximum temperature gradient in the wall is 10 °С/mm, and at the bottom – 6 °С/mm. It has been established that the working surface of the lining warms up sufficiently to avoid thermal shock when steel is poured into the ladle. The results of the research can be useful for optimizing the process of thermal preparing steel pouring ladles.

Performance evaluation of modified forced convection solar dryer with energy storage unit for drying of elephant apple (Dillenia indica)

AbstractThe development and performance of a modified force convection solar dryer (MFCSD) for drying elephant apple slices have been presented in this research. The MFCSD consists of two solar collectors and a drying chamber of 20 kg drying capacity. The secondary collector is integrated with thermal energy storage unit using a phase change material—paraffin wax. Performance analysis of the MFCSD was studied for drying elephant apple (Dillenia indica) slices. The proposed design enhanced the collector thermal efficiency by 12% as compared to a conventional glass collector. Drying of elephant apple slices in MFCSD will limit exergy losses and increase exergy efficiency. The estimated uncertainty of the collector chamber and the drying unit of the proposed MFCSD were obtained as ±3.3% and ±1.0%. Quality analysis (proximity analysis and textural properties) of the fresh as well as samples dried in open sun drying, tray drying, and MFCSD was carried out. The contents of carbohydrates (47.85 ± 2.66) and protein (21.24 ± 1.68) were high in samples dried in MFCSD when compared to samples dried in other two methods. The ash content of the sample dried in MFCSD was found to be 10.25 ± 0.15%, which was higher than samples dried in tray dryer. The payback period for drying elephant apple in MFCSD is 2.56 years, which is lower than the lifetime period (20 years) of the dryer.Practical ApplicationsA traditional method practiced by small farmers for drying high‐value perishable fruits is conventional open sun drying (OSD). Owing to slow drying rate and excessive heating, products dried under the open sun lose their nutritious and medicinal qualities. The present work details the construction of a low‐cost solar dryer for the drying of elephant apple. The aim of the drying kinetics to develop the architecture aspects of the solar dryer is to refine the drying systems. The results showed that the performance of modified force convection solar dryer (MFCSD) assisted with thermal storage could improve the quality of dried elephant apple slices and reduce drying time in comparison with an OSD method and a tray drying method. MFCSD would be a suitable alternative to the conventional dryers employed commonly in the industries for the drying of high‐valued agricultural products, and it can also be restructured to any size according the requirements.

Effect of Particle Size and Transparent Solar Dryer Cover on the Proximate Analysis of Dried Onion

In this work, we investigate effect of particle size and transparent solar dryer cover on the proximate analysis of dried onion.
 A solar drying unit was developed and constructed for drying the of red onion slices in order to determine the proximate composition of fresh and dried red onion using multi-crop direct solar dryer. Also, the evaluation and effect of particles size and multi-crop transparent solar dryer cover on the proximate analysis of red onion during drying. Consequently, the higher efficiency of the solar collector was obtained at the higher airflow rate. The moisture content of dried onion slices was strongly affected by the thickness of the onion slices and the density of the polyethylene. The final moisture content of dried onion slices ranged from 10.85% to 13.01%, 4.95% to 6.01% ash, 4.69% to 5.26% fibre, 11.17% to 13.09% fat, 6.70% to 5.60% protein and 68.64% to 68.03% carbohydrate for particle sizes of 3 mm, 5 mm and 7 mm dry-basis depending on drying temperature cycle for low density polyethylene cover. While the final moisture content of dried onion slices ranged from 9.85% to 12.01%, 5.96% to 6.01% ash, 3.69% to 4.26% fibre, 13.17% to 12.09% fat, 5.70% to 6.60% protein and 61.64% to 58.03% carbohydrate for particle sizes of 3 mm, 5mm and 7mm dry-basis depending on drying temperature cycle for high density polyethylene cover.

Optimizing Solvent Selection and Processing Conditions to Generate High Bulk-Density, Co-Precipitated Amorphous Dispersions of Posaconazole.

Co-precipitation is an emerging method to generate amorphous solid dispersions (ASDs), notable for its ability to enable the production of ASDs containing pharmaceuticals with thermal instability and limited solubility. As is true for spray drying and other unit operations to generate amorphous materials, changes in processing conditions during co-precipitation, such as solvent selection, can have a significant impact on the molecular and bulk powder properties of co-precipitated amorphous dispersions (cPAD). Using posaconazole as a model API, this work investigates how solvent selection can be leveraged to mitigate crystallization and maximize bulk density for precipitated amorphous dispersions. A precipitation process is developed to generate high-bulk-density amorphous dispersions. Insights from this system provide a mechanistic rationale to control the solid-state and bulk powder properties of amorphous dispersions.

Architectural Environmental, And Process Flow in Constructing Modern Factories for Manufacturing Eco-Friendly Furniture

Today, a dominant trend in factory construction is to account for the eco-economic aspects of their further operations. It requires sustainable technological solutions, with regard for structural specificities or for production technology used. At the same time, the buildings shall be architecturally attractive and distinct. In the paper, the author considered architectural, technological, structural, ecological, and economic factors for construction of wood-processing and furniture-making facilities. The author analyzed the actual Project Design to build the type of facility in Krekhiv village, Zhovkva district, Lviv region (western Ukraine) as commissioned by a well-known French company (the author have been engaged in the design). The study focused on a wood-processing Woodman company designed for the midtech production of edge glued panels and furniture. According to the design documentation by types of products planned, the Project Design provided for the following production units: unit for wood-sawing and drying; unit for mechanical processing of wood, production of edge glued panels and furniture; unit for mechanical repairs; and an administrative and services unit. The anticipated annual production capacity is: for edge glued panels – 600 m3 a year, furniture production– up to 4,000 pc a year. “Wood-sawing unit”, according to the Project Design, is organized according to the following principles of production technology based on the stages and operations: stockholding and storage of round timber (sawtimber); cutting the sawtimber into the shaped timber and logs; stocking the sawn timber (untrimmed boards) into stockpiles and on separators for further atmospheric and chamber drying. Sawn timber drying is taking place in the “Drying Unit”. It is the process of moisture removal from timber to a certain degree of humidity. The Project Design provided for the atmospheric drying of logs and boards in the furnished stockpiles under the roof, and artificial seasoning in a steam-curing and drying chambers. The artificial seasoning technology for sawn timber and logs is organized with the help of drying chambers and a boiler room with a sawdust bunker. The “Unit for Mechanical Wood Processing, Production of Edged Glued Panels and Furniture” is used for production of the edged glued panels from the sawn timber coming from hardwood (beech, oak). The production process of the edged glued panels includes the following stages: 1) cross-cutting of dry boards; 2) line cutting of board edges for the rough-sawn stock; 3) primary mechanical processing; 4) sorting by quality, color; 5) end-jointing gluing line; 6) log finishing; 7) press-molding of logs into panels; 8) panel surface preparation; 9) size cutting; 10) preservative treatment; 11) quality control; 12) storage and sales. "Administrative and Service Block", according to the Project Design, is an inbuilt part of the Main Building (Unit). It is a two-story insert separated with the fire safety barriers from the manufacturing facilities. It has isolated outside entrances and a technological corridor linking the manufacturing facilities. With account for production process requirements, fire safety, and sanitary standards, the Unit is divided into several personal services rooms for the staff and administrative rooms.

Improving the efficiency of solar drying unit with PCM (Paraffin wax)

The renewable energy source like solar is been used in this projects to produce more efficiency in a solar dryer. It is one the most reliable energy source and that does not pollute the environment and green house free emission. In this project work we use sunlight to dry the crops and to preserve the dry fruits we are using sunlight. The motivation of the work is to use a solar dryer with phase change material. With the help of PCM we can able to increase the efficiency of solar dryer because of increasing the contact area of the crops with PCM during off sunlight. In this project work we use indirect solar radiation principle because PCM will absorb the solar radiation and that will be emitted during the night time. A absorber plate is used to absorb the solar radiation. Once after receiving the radiation from the sun that is been transferred to the chamber where the crops are been provided. In that chamber we will be having the PCM box that will be in solid state and once after receiving the solar radiation phase change will be taking place from solid to liquid phase. Once the sun starts to set off the solar radiation will not be available so during that time PCM is used to transfer the heat. The moisture present in the crop is been removed with the help of the heated air. With the help of the above information the crop drying process is been evaluated with the help of calculation.

Comprehensive Analysis of Solar Dryer with a Natural Draught

ABSTRACT A solar dryer has been examined critically by using a constant drying model. The effect of the dynamic losses, intrinsic properties such as thermodynamic, hydrodynamic and psychometric factors, and natural draught during the practical application of the solar drying unit has been investigated. Carson and Moses, and the dynamic and static pressure correlations with the flow field have been used to determine the flow pattern inside the collector, the drying chamber, and the chimney. The energy allocation throughout the drying process has been evaluated by a Sankey diagram. The psychrometric calculation has been made by applying the steady-state-steady flow conditions (SSSF) on the carrier fluid (air). The average drying rate for the given design is 0.31 kg·h−1. The overall drying system efficiency is found to be 19%. The net static-regain (S.R) in the ducting system due to the sudden expansion is 2.22 N·m−2. The plume height for an efficient dilution of outgoing hot air is 1.17 m in addition to the given design. The flat plate collector efficiency for the given design was 26%. The surface temperature of the specimen should not be more than 321 K during a constant rate period. The pressure loss due to sudden contraction was found to be 73.48% lower than that of sudden expansion. Drying consumed 0.3% of the global irradiance for the drying purpose, whereas 57% of net received energy was absorbed by carrier fluid. The study encompassed the variability in the input that influence the performance of the solar collector since quantitative workout might not be effective unless the rheology is considered.

РАЗРАБОТКА И ИСПЫТАНИЕ СОЛНЕЧНОЙ УСТАНОВКИ С ПОЛИКАРБОНАТНЫМ ПОКРЫТИЕМ ДЛЯ СУШКИ ПРОДУКТОВ СЕЛЬСКОГО ХОЗЯЙСТВА

The proposed solar drying system significantly reduces the drying time and improves the quality of the product, including the preservation of vitamins. When drying rosehip, a laboratory analysis for vitamin "C" showed that 28% of this vitamin is destroyed during natural drying, and 17% when using a solar dryer.The drying speed increases by 2.5 - 4 times compared to traditional outdoor drying.In the proposed installation, you can dry different agricultural products, you can change the coating of the solar drying unit. In S/D, the air temperature is higher than in the environment from about 13 to 32 degrees Celsius, depending on weather conditions.The drying process in the S/D apparatus allows you to ensure the purity of the products. S/D is covered and during the drying process the product is not contaminated with dust and rain, by influence of dew, is not damaged by birds, insects or wasps.This device is convenient for transportation, during the day it can be moved and rotated to align to the sun.The proposed solar dryer is easy to manufacture and can be widely used in large and small farms, private and subsidiary farms.

Noise Exposure Levels in Black Tea Processing Factories and Its Effects on Employees

The aim of this study was to determine the daily noise exposure levels in black tea processing factories and to evaluate its effects on employees' occupational health and safety. In the study, the sound pressure level dBA values were measured at the ear levels of the employees in each production unit in three tea factories operating in Artvin Province. These factories where the measurements were made consist of withering, curling, oxidation, drying (boiler and stove) and classification units. These units include various systems and mechanisms formed by conveyors, fans, steam heaters, boilers, reducers, pallets, hoods, screens, gears, and drums. In the measurements performed considering the ISO 9612:2009 (Acoustics Determination of Occupational Noise Exposure Engineering Method) standard, a sound pressure level meter in Type-2 class complying with the requirements of the IEC 61672-1: 2002 was used. A weighted equivalent sound pressure levels were determined using the measured values. Considering these values and working times, personal daily noise exposure levels were calculated. It was determined that the equivalent sound pressure levels and daily personal noise exposure levels at the employee ear level were in the range of 77-87 dBA and 74-83 dBA, respectively. Curling units have the highest equivalent sound pressure level (86.81 dBA) and daily personal noise exposure level value (83.10 dBA) compared to other units, while boilers have the lowest equivalent sound pressure level (76.75 dBA) and daily personal noise exposure level value (73.55 dBA). Considering the regulation on protection of employees from noise related risks, it was concluded that the daily noise exposure level reached the lower exposure action value (80 dBA) in these factories. The study showed that the health and work efficiency of the employees could be adversely affected by noise in tea factories, considering various research results and Regulations on noise.

Mathematical modelingof heat and mass transfer processes in the adsorbers of the air purification system

The present work is devoted to the study of the processes of heat and mass transfer in the adsorbers of the preliminary drying unit of the atmosphere purification system. A mathematical model has been developed that adequately reflects the physical processes at all stages of the adsorption cycle.Algorithms for solving problems and programs for calculating heat and mass transfer processes in an adsorption regenerated installation are obtained, results of parametric calculations of heat and mass transfer processes at each stage of the adsorption cycle and for the entire cycle as a whole are obtained.

Modelling of a Continuous Veneer Drying Unit of Industrial Scale and Model-Based Anova of the Energy Efficiency

Modelling of a Continuous Veneer Drying Unit of Industrial Scale and Model-Based Anova of the Energy Efficiency

The result of an experimental study of the processing of silkworm cocoons

To ensure uniform temperature in the infrared vibratory drying unit and to preserve the quality of the final product during the initial processing of silkworm cocoons, the temperature field was studied using a thermal imager. Using a thermal imager, you can measure the temperature in contactless and remote processes. At the same time, you can obtain temperature information from several points. The thermal imager measures infrared radiation in the long-wavelength range within the field of view and automatically detects cold and hot spots. Based on this, the temperature of the measured object is calculated. The thermal image appears on the thermal imager screen and the obtained image results are processed on a computer.

Investigation of humid air physical properties influence on the heat and mass transfer processes calculation accuracy

Humid air is a mixture of dry air and water vapor and is widely used in various power and technical devices. Most theoretical studies of the properties of humid air are based on Mendeleev-Clapeyron ideal gas equa-tion, which doesn’t take into account the association, intermolecular interaction, and particularities of the thermodynamic behavior of humid air as a mixture of gases. The use of this equation leads to inaccuracy in determining the parameters of the state of humid air, which can reach up to 55 %. Therefore, the issues con-cerning the actual properties of humid air determining remain poorly understood. The ideal gas model is based on Mendeleev-Clapeyron equation. To study the actual parameters of the humid air state and its properties, Vukalovich-Novikov’s and Molie’s real gas state equations have been used.Several equations of the state of real gas, taking into account the interaction of water vapor molecules have been considered. The actual physical properties of humid air are determined, and their influence on the coupled heat and mass transfer processes for various conditions is evaluated. The actual values of the thermophysical properties of humid air have been derived. The thermodynamic limits for humid air have been determined using Mendeleev-Clapeyron’s, Vukalovich-Novikov’s and Molie’s state equations. It has been proved Vukalovich-Novikov’s state equation to be the best to represent the quantitative relations between the pressure, specific volume, and the temperature of saturated water vapor. Its application reduces the error of calculations by 39–50 %. The results obtained allow to improve the accuracy of calculating heat and mass transfer when designing contact heat exchangers, convective drying units and hygroscopic desalination plants, compression processes with water or water vapor injection, as well as the processes of mixing flue gases with water vapor in the combustion chambers of gas-steam installations.