Experimental study on sawdust gasification in a spout–fluid bed reactor

This paper summarizes the experimental results of sawdust gasification in a spout–fluid bed reactor. Three scenarios were investigated in this study. In the base case scenario, a total of 15 experiments consisting of three different flow rates (55, 65 and 75 m³ h^{? 1}) of primary air of each of having five equivalence ratios (ER) (0.35, 0.3, 0.25, 0.2 and 0.15) were conducted. The influence of secondary air in the freeboard and the effect of the recirculation of carryover captured by the cyclone to the reactor's freeboard at an ER of 0.25 were investigated in two other scenarios. Higher heating values of 3.02 and 5.15 MJ Nm^{? 3} were obtained with the ER values of 0.35 and 0.15, respectively, in the base case. However, opposite trend was observed for the tar content in the producer gas. At ER of 0.35, a value of 2.35 g Nm^{? 3} was found compared with 8.4 g Nm^{? 3} at ER of 0.15. The tar content in the producer gas was reduced from 5.63 to 1.53 g Nm^{? 3} when secondary air was supplied in the freeboard due to an increase in temperature. The gasification efficiency was increased from 24.96% at the base case to 36.22% with the recirculation of carryover. Higher heating value of producer gas was found to be 4.2–4.4 MJ Nm^{? 3} in this case. The second law analysis of this process estimated the average exergy efficiency as 35.92% at ER of 0.35 and it increased with increasing ER. The recirculation of carryover not only increased the carbon conversion efficiency but also the exergy efficiency. Copyright © 2010 John Wiley & Sons, Ltd.     

To study physical compatibility between dibasic calcium phosphate and cohesive actives using powder rheometer and thermal methods

Aim: An attempt is made to provide better understanding of the compatibility aspect of excipients with different properties of active pharmaceutical ingredient (API) using various rheological, thermal and morphological studies conducted on binary mixtures of Dibasic Calcium Phosphate anhydrous (DCP-A) and Dibasic Calcium Phosphate dihydrate (DCP-D) forms with cohesive API’s (Acetaminophen and Aspirin).

Method: Binary mixtures of DCP’s were prepared by addition of 0% w/w to 50% w/w of the API in each powder blend. Powder rheological analysis were conducted using FT4 powder rheometer, rotational shear cell and empirical approaches such as angle of repose (AOR), Hausner ratio (HR) and Carr’s index (CI). Thermal analysis was conducted using differential scanning calorimetry (DSC) and thermal effusivity. Morphological studies were conducted using Scanning Electron Microscopy (SEM) to determine the fundamental differences between powder materials.

Result/Conclusions: Powder rheometer showed distinctive understanding in the flowability behavior of binary mixtures with addition of increasing proportion of API’s than empirical approaches. Thermal approaches revealed the potential interaction of water of crystallization DCP-D while such interaction was absent in DCP-A. Binary mixtures prepared using DCP-D were better flowable while blends containing DCP-A were better in stability (physical), compressibility and permeability. This study allows the scientist to understand the powder packing of different blends with their flowability and compressibility parameter and helps selection of appropriate form of hydrate for relevant API.     

Modeling traceability information in soybean value chains

Identification of the information to be recorded is the most important requirement for developing an effective traceability system. In this paper, we present a soybean value chain and model the information capture by three links in the chain including the farming, bulk handling and processing sectors. Internal information capture points were identified for each sector and the corresponding traceability information to be recorded was determined. In-depth analyses were conducted for a soybean elevator and an oil and meal processor to determine the importance of traceability information from their perspective. A lot of information is available at different links in the soybean value chain. The method presented here can be used to create a standardized list of data elements that need to be recorded internally or exchanged with other links in the chain. A UML class diagram is developed to represent a method for modeling the product, process, quality and transformation information at any link in the chain. Finally, some suitable technologies for electronic information exchange within the food supply chains are presented.     

An investigation of MSW gasification in a spout-fluid bed reactor

This paper presents the experimental results of MSW gasification in a spout-fluid bed reactor. Municipal solid waste (MSW) modeled based on compositions of Bangkok waste transfer station “On-nuch” was used as the fuel. Three scenarios were investigated in this study. In the base case scenario, only primary air of equivalence ratios (ER) 0.35, 0.3, 0.25, 0.2, and 0.15 were used. The other two scenarios investigated the influence of secondary air in the free board, and the effect of the recirculation of carryover captured by the cyclone inside the reactor's free board at an ER of 0.25. In the base case, higher heating values of 2.40–5.05 MJ/Nm³ were obtained with the ER values of 0.35–0.15, respectively. However, opposite trend was observed for the tar content. At ER of 0.35, a value of 11.37 g/Nm³ was found compared to 20.76 g/Nm³ at ER of 0.15. The tar content in the producer gas was reduced from 14.47 to 10.98 g/Nm³ when secondary air was supplied in the freeboard due to an increase in temperature. The gasification efficiency was increased from the base case which was 35.78 to 38.99% with the recirculation of carryover. Higher heating value of producer gas was found to be 4.4–4.9 MJ/Nm³ in this case.     

Framework for implementing traceability system in the bulk grain supply chain

Implementation of a traceability system in the bulk grain supply chain is a complex task. Grain lots are often commingled to meet buyer specifications and the lot-identity is not maintained. In this paper, a systems approach is used to develop methods for implementing bulk grain supply chain traceability in the United States, that includes both internal and chain traceability. First, the usage requirements of a traceability system are defined for all the actors in the supply chain. Second, a model is developed for implementing internal traceability system for a grain elevator that handles specialty grain. Then, we develop a model for information exchange between the supply chain actors. The model shows what grain lot information must be recorded and then passed on to the next actor. A sequence diagram is developed to show the information exchange in the grain supply chain when a user requests additional information about a suspect product. Finally, we discuss some suitable technologies to enable this information exchange. A few sample XML documents are shown for the transfer and sharing of information in the grain supply chain.     

Quality of US Soybean Meal Compared to the Quality of Soybean Meal from Other Origins

Quality of soybeans and soybean meals (SBM) from non-US and US origins were compared. The US SBM was more consistent with higher digestibility (by KOH solubility), lower fiber and better quality of protein (by essential amino acid levels) than SBM of other major export origins (Argentina, Brazil and India). Protein quality carried through from whole soybeans to SBM, for a given origin. While the protein content was higher for the SBM from Brazil, the percentage of total digestible amino acids was highest for the SBM from the US and China. The US SBM had the highest content (total) of five essential amino acids for both poultry and swine feed uses, which when coupled with higher digestibility, would give US meal an advantage in rations balanced on amino acids. The mean particle size for all SBM from all origins was within the desirable range specified by nutritionists. The US soybeans were lower in protein than Brazilian soybeans, but higher than Argentine soybeans. The crude protein disadvantage of US soybeans was offset by higher concentrations of the essential amino acids in the lower protein soybeans. The US soybeans were lower in oil content than soybeans from either of the South American origins. Average protein and oil contents of US soybeans were consistent with the 2003 and 2004 annual soybean quality surveys. The US SBM held an advantage in digestibility and concentration of key amino acids in all three studies.     

Flow of viscoelastic surfactants through porous media

We compare the flow behavior of viscoelastic surfactant (VES) solutions and Newtonian fluids through two different model porous media having similar permeability: (a) a 3D random packed bed and (b) a microchannel with a periodically spaced pillars. The former provides much larger flow resistance at the same apparent shear rate compared to the latter. The flow profile in the 3D packed bed cannot be observed since it is a closed system. However, visualization of the flow profile in the microchannel shows strong spatial and temporal flow instabilities in VES fluids appear above a critical shear rate. The onset of such elastic instabilities correlates to the flow rate where increased flow resistance is observed. The elastic instabilities are attributed to the formation of transient shear induced structures. The experiments provide a detailed insight into the complex interplay between the pore scale geometry and rheology of VES in the creeping flow regime. © 2017 American Institute of Chemical Engineers AIChE J, 64: 773–781, 2018     

A multi-objective optimization approach to balancing cost and traceability in bulk grain handling

This paper proposes a multi-objective optimization model that provides an effective method for minimizing traceability effort by minimizing the food safety risk caused by lot aggregation at a grain elevator. A mathematical multi-objective mixed-integer programming (MIP) model is proposed with two objective functions that allow in calculating the minimum levels of lot aggregation and minimum total cost of blending grain. Constraints on the system include customer contract specifications, availability of grain at the elevators and the blending requirements. The solutions include quantities of grain from different storage bins to be used for blending for a shipment while using the minimum number of storage bins and minimum total cost. The numerical results are presented for a corn shipment scenario to demonstrate the application of this model. Pareto optimal front is computed for the problem for simultaneous optimization of lot aggregation and cost of blending. Sensitivity analysis is conducted to analyze the application of the model under different operating conditions.     

Data mining for recognizing patterns in foodborne disease outbreaks

This paper introduces a new methodology for discovering patterns in foodborne disease outbreaks using a data-driven approach. Specifically, our approach uses three data mining methods, namely attribute selection, decision tree learning, and association rule discovery, to extract previously unknown and meaningful patterns that connect specific types of foodborne diseases outbreaks with associated foods vehicles and consumption locations. We use this approach to study the four most common disease causing etiologies in the Center for Disease Control (CDC) database of foodborne disease outbreaks in the year 2006, namely Salmonella enteritidis, Salmonella typhimurium, Escherichia coli, and Norovirus. The analysis reveals numerous patterns of how each of these outbreaks types relates to specific foods and locations. The discovery of such patterns in foodborne disease outbreak data can be very useful is determination and implementation of suitable intervention techniques. In particular, if the associations between different food types and consumption locations are known then custom intervention techniques including specific training methods can be designed to train individuals in hygienic food handling, preparation, and consumption practices.