Feedstock Preparation by Gasification

2019 ◽  
pp. 165-208
Author(s):  
James G. Speight
Keyword(s):  
Feedstock Preparation

STUDY OF FEEDSTOCK PREPARATION AND DEBINDING PROCESS OF INJECTION MOULDED HIP STEM Co-Cr-Mo ALLOY POWDER USING WAX BASED BINDER

2014 ◽  
Vol 22 (1) ◽  
pp. 69-83
Author(s):  
Mohd Afian Omar ◽  
◽  
Noorsyakirah Abdullah ◽  
Rosliza Sauti ◽  
Fauzi ismail ◽  
...  
Keyword(s):  
Alloy Powder ◽  
Debinding Process ◽  
Feedstock Preparation

Manufacturing of Nanocomposites via Powder Injection Molding: Focusing on Thermal Management Systems—A Review

2020 ◽  
Vol 143 (4) ◽  
Author(s):  
Maryam Hosseinpour ◽  
Hassan Abdoos
Keyword(s):  
Injection Molding ◽  
Thermal Management ◽  
Electronic Device ◽  
New Technology ◽  
Rapid Evolution ◽  
Industrial Applications ◽  
Powder Injection Molding ◽  
Powder Injection ◽  
Metal Matrix Nanocomposites ◽  
Feedstock Preparation

Abstract The rapid evolution of electronic and information technology has increased the performance of the electronic processors significantly. Achieving the optimal performance in a smart electronic device poses a serious challenge as the heat generated during operation will reduce the performance of the device which makes thermal management a determinant factor. Powder injection molding (PIM) is an appropriate and relatively new technology used for mass production of small delicate parts with complex shapes and desired properties. One of the latest advances in the PIM process is the production of metal matrix nanocomposites with huge industrial applications, particularly in electronics manufacturing. Manufacturing of efficient complex-shaped nanocomposites, as thermal management components (passive heatsink), could be achieved through the PIM process. On the other hand, what could pose a challenge is the presence of nanoparticles affecting on the different stages of PIM process including feedstock preparation, molding, debinding, and sintering. In this paper, the effect of nanoparticles on different stages of PIM for the production of heatsinks is investigated. Then, the manufacturing of Cu-, Al-, and Mg-based nanocomposites by powder injection molding, as heatsinks, is reviewed followed by investigating the related advantages and limitations.

Effect of Sintering Temperature on the Tribological Behavior of Plasma Assisted Debinded and Sintered MIM Self Lubricating Steels

2010 ◽  
Author(s):  
Jose´ Daniel B. de Mello ◽  
Cristiano Binder ◽  
Aloisio Nelmo Klein ◽  
Roberto Binder
Keyword(s):  
Friction Coefficient ◽  
Sintering Temperature ◽  
Metallic Matrix ◽  
Solid Lubricants ◽  
Solid Lubrication ◽  
Metal Injection Molding ◽  
Processing Route ◽  
Second Phase ◽  
New Processing ◽  
Feedstock Preparation

Solid lubrication and solid lubricants are one of the most promising choices for controlling friction and wear in energy efficient modern systems. The production of self lubrication composites containing second phase particles incorporated into the volume of the material appears to be a promising solution. A new processing route to obtaining a homogeneous dispersion of discrete solid lubricant particles in the volume of sintered steels produced by metal injection molding (MIM) was recently presented. This new route was achieved by in situ formation of graphite nodules due to the dissociation of precursor (SiC particles) mixed with the metallic matrix powders during the feedstock preparation. Nodules of graphite (size ≤ 20μm) presenting a nanostructured stacking of graphite foils a few nanometers thick were obtained. The thermal debinding, as well as the sintering, was performed in a single thermal cycle using a Plasma Assisted Debinding and Sintering (PADS) process. In this work, we present and discuss the effect of sintering temperature on the tribolayer durability and average friction coefficient in the lubricious regime (μ<0.2) of plasma assisted debinded and sintered self lubricating steel produced by metal injection mould technique. Three different temperatures (1100, 1150 and 1200 °C) and six different SiC contents (0–5%) were analyzed. Friction coefficient was little affected by the sintering temperature. However, the durability of the tribo layer formed on the sliding interface was greatly increased (5X) for the lower sintering temperature (1100°C).

Investigation on Feedstock Preparation for Micro-Cemented Carbide Injection Molding

2018 ◽  
Vol 18 (2) ◽  
pp. 96-102
Author(s):  
Abdolali Fayyaz ◽  
Norhamidi Muhamad ◽  
Abu Bakar Sulong
Keyword(s):  
Flow Behavior ◽  
Flow Characteristics ◽  
High Viscosity ◽  
Cemented Carbide ◽  
Solid Loading ◽  
Powder Particle Size ◽  
Powder Particles ◽  
Particle Size And Morphology ◽  
Size And Morphology ◽  
Feedstock Preparation

Abstract This research was focused on mixing of submicron cemented carbide (WC-Co-VC) powder and binder. WC-Co-VC powder particle size and morphology were analyzed by laser diffraction and field emission scanning electron microscopy. The WC-Co-VC powder was kneaded with a paraffin wax based binder system. Based on critical solid loading, the feedstock with different solid loadings between 49 to 51 vol.% was prepared. Finally, the flow behavior of different feedstocks was investigated. Morphology of powder revealed that the particles of powder are slightly agglomerated and irregular in shape. The result of mixing indicted that the torque value increases as the solid loading increase from 49 vol.% to 51 vol.%. The feedstock exhibited homogeneity and the powder particles are homogenously coated with binder. The feedstock with solid loading of 51 vol.% is sensitive to temperature and showed high viscosity values. The feedstock with solid loadings of 49 and 50 vol.% had good compatibility and flow characteristics.

Integrated Oxygen-Free Gasification-Gas Turbine Power Concept: A Low-Emissions Alternative for Small-Scale Coal Plants

2011 ◽  
Author(s):  
Rory F. D. Monaghan ◽  
Monem H. Alyaser
Keyword(s):  
Sensitivity Analysis ◽  
Gas Turbine ◽  
Heat Recovery ◽  
Power Plants ◽  
Electrical Energy ◽  
Small Scale ◽  
Base Case ◽  
System Sensitivity ◽  
Spreadsheet Model ◽  
Feedstock Preparation

A power plant concept with the potential to replace the large fleet of ageing, small-scale (< 50 MWe), inefficient, polluting, and soon-to-be obsolete coal-fired power plants is proposed. The proposed plant comprises a bituminous coal-fed oxygen-free gasifier, low-temperature syngas cleanup system and an open-cycle gas turbine with heat recovery. Heat is supplied to the gasifier through combustion of a portion of the cleaned syngas produced by it. Since the proposed plant employs only a gas turbine, with no steam bottoming cycle, heat recovery from the gas turbine and its integration with the rest of the plant is crucial. A thermodynamic model of the plant has been created to assess its feasibility based on overall efficiency and emissions of CO2, SO2, mercury and particulates. The model comprises submodels for feedstock composition and enthalpy, as well as first-order thermodynamic models for each of the plant components including the gasifier, feedstock preparation, heat exchangers and steam generators, contaminant removal, combustors and turbomachinery. The results of the analysis show base case plant thermal efficiency of 38.2% on a HHV basis, which is roughly 5% points higher than that for a similarly-sized pulverized coal combustion (PCC) plants. Emissions of CO2, SO2, mercury and particulates per unit electrical energy produced in the base case are: 0.774 kg/kWh, 47.2 g/MWh, 2.37 g/GWh and 28.2 g/MWh, respectively. These values are well below emissions from similarly-sized PCC plants, which have been assessed using a spreadsheet model. The model of the proposed plant has been used to assess overall performance when torrefied pine wood is co-gasified with coal. Results show a slight decrease in plant efficiency with increasing co-gasification, with large decreases in CO2, SO2 and mercury emissions. Emissions of particulates increase slightly with co-gasification. Finally the model has been used to perform sensitivity analysis on the proposed system. Sensitivity analysis highlights the need for greater understanding of gasifier performance under a range of conditions.

Feedstock Formulation of Open-Pore Cell Copper Foam via Metal Injection Molding

2016 ◽  
Vol 1133 ◽  
pp. 290-294
Author(s):  
Noorsyakirah Abdulah ◽  
Mazlan Mohamad ◽  
Mohd Afian Omar ◽  
Muhammad Jabir Suleiman @ Ahmad ◽  
Ahmad Aswad Mahaidin ◽  
...  
Keyword(s):  
Injection Molding ◽  
Metal Injection Molding ◽  
Injection Molding Process ◽  
Molding Process ◽  
Powder Morphology ◽  
Space Holder ◽  
Copper Foam ◽  
Vertical Injection ◽  
Injection Molded ◽  
Feedstock Preparation

Feedstock preparation is one of the most crucial steps that will influence the metal injection molding process. In this study, the properties of Cu and space holder powder were determined. Powder morphology was captured using Scanning Electron Microscopy (SEM). Three different ratios of feedstocks were premixed with potassium carbonate as space holder using Turbulence Shaker mixer prior to mixing with constant binder system consist of waste rubber (WR). Mixes of three feedstocks with from 40, 50 and 60 wt. % were carried out in Brabender Plasticoder. All feedstocks were mixed at constant powder loading. The feedstocks were successfully injection molded using Vertical Injection Molding machine at 200°C.

Powder Injection Moulding of Alumina Using PEG/PVB Binder Systems

2013 ◽  
Vol 545 ◽  
pp. 173-176 ◽  
Author(s):  
Nutthita Chuankrerkkul ◽  
Pat Sooksaen ◽  
Piyawan Pakunthod ◽  
Tutiyachan Kosalwit ◽  
Wanwara Pinthong
Keyword(s):  
Injection Moulding ◽  
Removal Rate ◽  
Minor Component ◽  
Polyvinyl Butyral ◽  
Major Constituent ◽  
Powder Injection ◽  
Alumina Powder ◽  
Water Leaching ◽  
Powder Injection Moulding ◽  
Feedstock Preparation

Powder injection moulding (PIM) is a process that is suitable for a fabrication of small and complex shape components. It consists of 4 main steps: feedstock preparation by mixing powder and binder, injection moulding of the prepared feedstock into the desired mould, removal of the binder and finally sintering to obtain materials with specific properties. In this study, powder injection moulding of alumina (Al2O3), using polyethylene glycol (PEG) based binder systems, was investigated. PEG is soluble in water; therefore, the use of organic solvents required for debinding of wax-based binder system can be avoided. PEG with a molecular weight of either 1500 or 4000 was used as a major constituent together with polyvinyl butyral (PVB) as a minor component. Stearic acid was also added during feedstock preparation to act as a lubricant. After mixing the powder with the binder, a variety of Al2O3 feedstocks were injected into the moulds. The mouldings were prepared by a laboratory-scaled plunger-typed machine. Debinding was carried out using a combination of solvent extraction and thermal debinding. Water leaching tests were performed at 30 and 50 °C to study PEGs removal rate. The pyrolysis of PVB was completed during ramping up of the mouldings to the sintering temperature. The mouldings were subjected to sintering at 1500 °C in air. It was found from the study that PEG/PVB binder systems can be used for the preparation of alumina powder injection moulding feedstocks. Specimens retained their shapes during and after leaching of the PEGs.

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