Vykundeshwari Ganesan

Effect of moisture content and soluble level on the physical, chemical, and flow properties of distillers dried grains with solubles (DDGS).

ABSTRACT Distillers dried grains with solubles (DDGS) is a bulk material that has been widely used as a protein source for ruminants and nonruminants for more than two decades. DDGS is the nonfermentable processing residue (i.e., protein, fiber, fat, and ash) from fuel ethanol manufacturing. With the exponential growth of the fuel ethanol industry in the past several years, significant quantities (≈13.0 million tons in 2007) of distillers grains are now being produced. To effectively utilize these coproduct streams in the domestic market, DDGS must be transported greater distances and must be stored until final use. DDGS flow is often problematic as it can become restricted by caking and bridging that occur during shipping and storage. This flowability problem can present itself during dynamic and static flow conditions. This issue most likely results from physical or chemical interactions between particles (including particle size and shape), storage moisture, temperature, and relative humidity variation...

Effect of flow agent addition on the physical properties of DDGS with varying moisture content and soluble levels.

Distillers Dried Grains with Solubles (DDGS) is widely recognized as a highly nutritious animal feed ingredient. With the exponential growth of the fuel ethanol industry in the past several years, significant quantities of distillers grains are now being produced. To effectively utilize these feeds in the domestic market, these coproduct streams have to be transported greater distances, and must be stored in various structures until final use. Unfortunately, DDGS flow is often problematic, as it frequently becomes restricted by caking and bridging during storage and transport. This issue may arise from a number of factors, including storage moisture, temperature, relative humidity, particle size, time, or temperature variations. The objective of this study was to examine the effect of various moisture content levels (10%, 15%, 20%, 25%, and 30% d.b.) and calcium carbonate (a common flow agent) levels (0%, 1%, and 2% w.b.) on the resulting physical and flow properties (Carr indices) of DDGS with varying soluble levels (10%, 15%, 20%, and 25% d.b.). The results showed that DDGS flowability declined with increased soluble and moisture content levels. Flow agent (CaCO3) addition did not have a significant effect in improving the flow properties of DDGS. This may have been due to no surface affinity between DDGS and the flow agent particles, or too little inclusion of the flow agent.

Effect of Moisture content and Soluble levels on the Physical and Chemical Properties of DDGS

Over the past few decades, researches concerning handling and storage characteristics of bulk solids have been conducted to a large extent. Distillers Dried Grains with Solubles (DDGS) are a bulk material that has been widely used as a protein source for ruminants and non-ruminants for more than two decades. Distillers’ grains are energy dense as they contain high fat levels. With the exponential growth of the fuel ethanol industry in the past several years, significant quantities of distiller’s grains are now being produced. To effectively utilize these feeds in the domestic market, however, these coproduct streams are increasingly being transported greater distances, and must be stored until final use. DDGS flow is often problematic as it can become restricted by caking and bridging which occurs during transportation and storage. This issue probably results from storage moisture, temperature, relative humidity, particle size, time, or temperature variations. The objective of this phase of the study is to examine the effect of various moisture content levels (10, 15, 20, 25, 30% db) on the resulting physical and chemical properties of DDGS with varying soluble percentages (10, 15, 20, 25% db).

Modeling the flow properties of DDGS.

ABSTRACT Distillers dried grains with solubles (DDGS) are an excellent source of energy, minerals, and bypass protein for ruminants. With the remarkable growth of the U.S. fuel ethanol industry in the past decade, large quantities of distillers grains are now being produced. DDGS flow is often restricted by caking and bridging during its storage and transportation. In our previous works, increased soluble and moisture levels significantly affected the flow properties of DDGS. Currently, however, there is no model available to predict the flowability of DDGS. So the objectives of this study were to thoroughly investigate the data obtained from our previous work using exploratory data analysis techniques and to develop a comprehensive model to predict the flowability of DDGS. A simple and robust model (R2 = 0.93, SE = 0.12) was developed by combining the important flow properties obtained from conventional Carr and Jenike tests using dimensional analysis and response surface modeling. However, the model dev...

Sorption isotherm characteristics of distillers dried grains with solubles (DDGS).

Distillers dried grains with solubles (DDGS) is widely recognized as a highly nutritious animal feed ingredient. With the exponential growth of the fuel ethanol industry in the past several years, significant quantities of distillers grains are now being produced. To effectively utilize these feeds in the domestic market, these coproduct streams have to be transported greater distances and must be stored in various structures until final use. Unfortunately, DDGS flow is often problematic as it frequently becomes restricted by caking and bridging during storage and transport. This issue may arise from a number of factors, including storage moisture, temperature, relative humidity, particle size, and time variations. The objective of this study was to develop sorption isotherms for DDGS with varying soluble levels, in order to provide facility designers and operators with appropriate storage and transport information. Equilibrium moisture contents (EMC) of DDGS with four different soluble levels (10%, 15%, 20%, and 25% d.b.) were determined using the static gravimetric method at 10°C, 20°C, 30°C, and 40°C over four equilibrium relative humidity (ERH) levels of 60%, 70%, 80%, and 90%. The sorption capacity of DDGS increased with increasing temperature and soluble level, and followed a type III isotherm, which is commonly observed in high-sugar foods. The observed EMC values for 10%, 15%, 20%, and 25% (d.b.) solubles ranged from 8.61% to 47.07% (d.b.), 11.58% to 83.49% (d.b.), 13.72% to 90.70% (d.b.), and 15.03% to 132.01% (d.b.), respectively. Nine models were then applied to fit the isotherm data. The modified Henderson and modified Chung-Pfost models did not fit the data, however, as the regression coefficients did not converge. The modified Halsey and modified exponential models, on the other hand, were found to perform well for the isotherm data. As there was no common model to predict the sorption isotherms of DDGS with various soluble levels, a new EMC model was developed. This new model, termed the GMR (Ganesan-Muthu-Rosentrater) model, incorporated soluble level as one of the effects along with temperature and moisture content. The GMR model (R2 = 0.94; F = 977.55), followed by a new modified exponential 2 (NME2) model (R2 = 0.94; F = 934.43), produced the best fits for DDGS with varying soluble levels, and can be used to predict equilibrium moisture sorption behavior of DDGS.

Dynamic Water Adsorption Characteristics of Distillers Dried Grains with Solubles (DDGS)

ABSTRACT Distillers dried grains with solubles (DDGS) is one of the coproducts obtained from dry-grind ethanol manufacturing. As the ethanol industry is growing exponentially, the production of DDGS has been significantly increasing as well. To optimize the use of DDGS, it has to be economically transported from one part of the country to other parts, and stored efficiently. But DDGS has some flow issues, which often makes storage and transportation very problematic. So the objective of this study was to investigate the dynamic water adsorption characteristics of DDGS with four soluble levels at four temperatures and four relative humidities. Three mathematical models were then used to fit the adsorption data (Peleg, Pilosof, and Singh-Kulshrestha). As there was no model available for describing the water adsorption characteristics of DDGS with varying soluble levels at various temperature and relative humidity conditions, a new comprehensive model was developed. The new model, Ganesan-Rosentrater-Muthu (...

Modeling The Flow Properties Of Distillers Dried Grains with Solubles

Distillers dried grains with solubles (DDGS) are an excellent source of energy, minerals, and bypass protein for ruminants, and are also used in monogastric rations as well. With the remarkable growth of the US fuel ethanol industry in the past decade, large quantities of distillers grains are now being produced. DDGS flow is often restricted by caking and bridging during its storage and transportation. In our previous works, it has been found that increased soluble and moisture levels significantly affected the flow properties of DDGS. Currently, however there is no model available to predict the flowability of DDGS. So, the objectives of this study were to thoroughly investigate the data obtained from our previous work using exploratory data analysis techniques, and to develop a comprehensive model to predict the flowability of DDGS. A simple and robust model (R2=0.93; SE=0.12) was developed by combining the important flow properties obtained from both Carr and Jenike tests using dimensional analysis and response surface modeling. The model developed was exclusively based on the DDGS from one ethanol plant. As DDGS flow properties will differ with each plant, it is suggested to use this methodology to develop a similar model to predict the flowability of DDGS for other plants as well.

Flow Properties Of DDGS with Varying Soluble and Moisture Contents Using Jenike Shear Testing

Distillers dried grains with solubles (DDGS) are an excellent source of energy, minerals, and bypass protein for ruminants and are used in monogastric rations as well. With the remarkable growth of the US fuel ethanol industry in the past decade, large quantities of distillers grains are now being produced. Flow of DDGS is often restricted by caking and bridging during its storage and transportation. In our previous works, the Carr powder tester was used to measure various flow properties of DDGS. The objective of this study was to measure the flow properties (cohesion, effective angle of friction, internal angle of friction, yield locus, flow function, major consolidating stress, and unconfined yield strength) of DDGS using the Jenike shear tester. This work investigated the influence of four levels of solubles (10, 15, 20, and 25% db) and five levels of moisture content (10, 15, 20, 25, and 30% db) on the resulting flow properties of DDGS. With an increase in soluble levels, the flow function curves of DDGS shift in an anticlockwise direction towards the shear stress (sc) axis. Depending on the soluble level, above certain moisture contents, the moisture actually began acting as a lubricant, easing the flow of the DDGS. Also, with higher solubles and moisture levels, the compressibility of DDGS was found to increase. Overall, the DDGS was classified as a cohesive material, and it is likely to produce cohesive arching problems.

Flowability and Handling Characteristics of Bulk Solids and Powders – A Review

Much research regarding handling and storage characteristics of bulk solids has been conducted over the years. Physical properties of granular solids play a significant role in their resulting flow and storage behavior, and are therefore essential to design appropriate, efficient, and economic bulk solids handling and storage equipment and structures. Distillers Dried Grains with Solubles (DDGS) are a bulk material that has been widely used as a protein source for ruminants and non-ruminants for more than two decades. Distillers’ grains are energy dense as they contain high fat levels. With the exponential growth of the fuel ethanol industry in the past several years, significant quantities of distiller’s grains are now being produced. To effectively utilize these feeds in the domestic market, however, these coproduct streams are increasingly being transported greater distances, and must be stored until final use. DDGS flow is often problematic as it can become restricted by caking and bridging which occurs during transportation and storage. This issue probably results from storage moisture, temperature, relative humidity, particle size, time, or temperature variations. The objective of this study is to review the primary factors affecting flowability, handling, and storage of granular solids and powders, as well as appropriate test methodologies for these materials. Considering these will be helpful when examining granular flowability and storage challenges, including those surrounding the use of DDGS.

Sorption Isotherm Characteristics of Distillers Dried Grains with Solubles (DDGS)

Distillers Dried Grains with Solubles (DDGS) is widely recognized as a highly nutritious animal feed ingredient. With the exponential growth of the fuel ethanol industry in the past several years, significant quantities of distillers grains are now being produced. To effectively utilize these feeds in the domestic market, however, these coproduct streams are increasingly being transported greater distances, and must be stored in various structures until final use. Unfortunately, DDGS flow is often problematic, as it frequently becomes restricted by caking and bridging during storage and transport. This issue may arise from a number of factors, including storage moisture, temperature, relative humidity, particle size, time, or temperature variations. The objective of this study was to develop sorption isotherms for DDGS with varying soluble levels, in order to provide facility designers and operators with appropriate storage and transport information. Equilibrium moisture contents (EMC) of DDGS with four different soluble levels (10, 15, 20 and 25% db) were determined using the static gravimetric method at 10, 20, 30 and 40oC over four equilibrium relative humidity (ERH) conditions, ranging from 0.560 to 0.910. The sorption capacity of DDGS increased with increasing temperature and soluble level, and followed a type III isotherm, which is commonly observed in high sugar foods. The observed EMC values for 10, 15, 20 and 25% (db) solubles ranged from 8.61% to 47.07% (db), 11.58% to 83.49% (db), 13.72% to 90.70% (db), and 15.03% to 132.01% (db), respectively. Nine models were applied to fit the isotherm data. The Modified Henderson and modified Chung-Pfost models did not fit the data, however, as the regression coefficients did not converge. The Modified Halsey and modified Exponential models, on the other hand, were found to perform well for the isotherm data. As there was no common model to predict the sorption isotherms of DDGS with various soluble levels, a new EMC model was developed. This new model, termed the GMR (Ganesan-Muthu-Rosentrater) model, incorporated soluble level as one of the effects, along with temperature and moisture content. The GMR model (R2=0.9395 F=977.55), followed by a new modified Exponential 2 (NME2) model (R2=0.9368 F=934.43), produced the best fits for DDGS with varying soluble levels.