Matthew James Watson

IGNITION PHENOMENA AND CONTROLLED FIRING OF REACTION-BONDED ALUMINUM OXIDE

Abstract The reaction-bonded aluminum oxide (RBAO) process utilizes the oxidation of attrition-milled Al/Al2O3/ZrO2 powder compacts, that are heat treated in air, to make alumina-based ceramics. A simultaneous mass and energy balance has been used to model the propagation of the ignition front that has been observed during reaction-bonding. The model is used to determine conditions under which ignition can be avoided.

Wavelet techniques in the compression of process data

The objective of this paper is to explore the application of wavelets to the field of data compression in the process industry. The wavelet transform is compared with the discrete Fourier and cosine transforms. To examine a complete approach to data compression, quantization techniques are applied to the transformed coefficients. Different quantiser designs are used for the compression of data from an industrial distillation column. Comparisons are made with the Box-Car and backward-slope methods currently used in the process industries.

Hydrogen applications and research activities in its production routes through catalytic hydrocarbon conversion

Abstract The statistical information on the share of hydrogen sector-wise consumption indicates that 95% of the total consumption is utilized in ammonia synthesis, petroleum refining processes and methanol production. We discuss how hydrogen is used in these processes and in several smaller-scale manufacturing industries. We also present the trend of hydrogen used as fuel, and as an energy carrier in fuel cells for generating electricity, powering hydrogen vehicles, as well as in aerospace applications. Natural gas caters for approximately half of the total hydrogen production resources. Therefore, the scope is emphasized on relatively recent developments in research activities related to the conventional catalytic hydrocarbon processing technologies for the production of hydrogen derived from natural gas (methane), which are steam methane reforming, partial oxidation of methane and autothermal reforming. Hydrocarbon decomposition is included due to its potential to be industrialized in the future, and its benefits of producing clean hydrogen without emissions of greenhouse gases and generating carbon nanofibers or nanotubes as by-products that have the potential in various emerging applications. Attention is given to the efforts toward achieving hydrocarbon conversion improvements, energy savings through thermally efficient operation and reduced operational costs through minimization or elimination of coke formation in the catalytic processes.

Monolithic substrate support catalyst design considerations for steam methane reforming operation

Abstract This paper reviews the research undertaken to study the design criteria that address the monolithic support structure requirements in steam reforming operation for the effective mass transfer of process gases to the active sites and effective conductive heat transfer through tube wall to the active catalytic areas, as well as low pressure drop operation. Design considerations include selection of substrate materials that possess good mechanical strength to withstand the severe reaction conditions and prevent catalyst crushing that would lead to carbon formation and catalyst deactivation, and excessive heating of the tube that results in hot spots which is fatal to tube lifetime. The support’s mechanical properties are listed for the purpose of providing guidelines on verifying the structure durability. The practical aspect of packaging and stacking the monolith structures in the reformer tube for ease of loading and discharge is discussed to understand its readiness in industrial application.

Erratum to: Monolithic substrate support catalyst design considerations for steam methane reforming operation

The article has listed an incorrect reference as below: Baharudin L, Watson MJ. Monolithic substrate support catalyst design considerations for steam methane reforming operation. Rev Chem Eng 2018; 34: 481–501. The correct reference should be: Baharudin L, Watson MJ. Hydrogen applications and research activities in its production routes through catalytic hydrocarbon conversion. Rev Chem Eng 2018; 34: 43–72. (doi:10.1515/revce-2016-0040).

Potential of metal monoliths with grown carbon nanomaterials as catalyst support in intensified steam reformer: a perspective

Abstract A monolithic catalytic support is potentially a thermally effective system for application in an intensified steam reforming process. In contrast to ceramic analogues, metal monoliths exhibit better mechanical strength, thermal conductivity and a thermal expansion coefficient equivalent to that of the reformer tube. A layer of carbon nanomaterials grown on the metal monolith’s surface can act as a textural promoter offering sufficient surface area for hosting homogeneously dispersed catalytically active metal particles. Carbon nanomaterials possess good thermal conductivities and mechanical properties. The future potential of this system in steam reforming is envisaged based on hypothetical speculation supported by fundamental carbon studies from as early as the 1970s, and sufficient literature evidence from relatively recent research on the use of monoliths and carbon in catalysis. Thermodynamics and active interaction between metal particle surface and carbon-containing gas have resulted in coke deposition on the nickel-based catalysts in steam reforming. The coke is removable through gasification by increasing the steam-to-carbon ratio to above stoichiometric but risks a parallel gasification of the carbon nanomaterials textural promoter, leading to nickel particle sintering. We present our perspective based on literature in which, under the same coke gasification conditions, the highly crystallised carbon nanomaterials maintain high chemical and thermal stability.