Best available techniques in the fertilizer production industry: A Review

Treatment and disposal of emission gases used for fertilizer production are among the most pressing issues in the modern fertilizer industries. Associations such as the European Manufacturer Association are developing new techniques, i.e., best available techniques, to resolve such problems. Best available techniques have been developed by the European Manufacturer Association to standardize the solutions to common problems encountered in the fertilizer industry, such as optimization of pH, pressure, temperature, nitrogen content, and fertilizer particle size. The best available techniques aim at minimizing greenhouse gas emissions in the fertilizer industry as well as wastewater treatment and waste management. The high operation and investment costs in the fertilizer industry have prompted manufacturers to consider the application of the best available techniques

The Kinetics of Industrial Ammonia Combustion

This thesis uses experiments and modelling to determine the kinetics of industrial ammonia combustion over platinum gauzes. The study is motivated by the existing poor understanding of the kinetics under industrial conditions. A comprehensive literature review of ammonia combustion is given, which includes a historical study of the industrial process, the current understanding of the industrial reaction kinetics, and an overview of the surface reaction mechanism. For this study, to further investigate industrial combustion, a burner was built whose design parameters were based on individual plant data found in the literature. Two models of the system are presented, one for the kinetics, and another for the temperatures in the catalyst bed. The key finding from the kinetic model is how individual process parameters determine the selectivity of the combustion products. The temperature model shows that for combustion in air, the catalyst surface temperature is not constant throughout the gauze pack, as it is currently thought to be

Glass-fiber woven catalysts as alternative catalytic materials for various industries. A review

The chemistry and technology of new versatile multipurpose catalytic systems developed and studied by the authors for the purposes of heterogeneous catalysis are reviewed. A theoretical background for a successful search for these new catalytic systems is based on an unconventional approach with emphasis on an essential role of branched-chain reaction mechanisms of heterogeneous catalysis previously developed by the authoring team. The catalytic systems under study are based on silica (aluminoborosilicate) glass-fiber amorphous matrices doped with various metals and manufactured as articles with various types of woven structure. The specific features of these glass-fiber woven catalytic systems, such as their structure, phase state of the matrix, manufacture and activation methods, design of catalytic reactors in which they operate, as well as production technologies and operation methods, make a compelling case to regard them as a new separate class of catalysts. As compared to conventional catalytic materials, these new catalysts are highly efficient in neutralizing industrial gas emissions, in contact stages of the production of nitric acid and sulfuric acid, in various reactions of catalytic hydrocarbon processing, in water purification from nitrate and nitrite contaminants, in catalytic heat generation, etc

A Framework for Synergy Evaluation and Implementation in Resource Based Industries

This thesis involved the development of a framework for identifying and reusing potential industrial waste. It evaluates the chemical composition of wastes and links it to potential surrounding industries through a generic industrial outlay. Potential waste are then analysed experimentally and through simulation for feasibility and determining mass and energy balances. The latter are used for environmental analysis through LCA and economic evaluation through AspenPlus software. Two case studies have been assessed through the framework

Biomass in the manufacture of industrial products—the use of proteins and amino acids

The depletion in fossil feedstocks, increasing oil prices, and the ecological problems associated with CO2 emissions are forcing the development of alternative resources for energy, transport fuels, and chemicals: the replacement of fossil resources with CO2 neutral biomass. Allied with this, the conversion of crude oil products utilizes primary products (ethylene, etc.) and their conversion to either materials or (functional) chemicals with the aid of co-reagents such as ammonia and various process steps to introduce functionalities such as -NH2 into the simple structures of the primary products. Conversely, many products found in biomass often contain functionalities. Therefore, it is attractive to exploit this to bypass the use, and preparation of, co-reagents as well as eliminating various process steps by utilizing suitable biomass-based precursors for the production of chemicals. It is the aim of this mini-review to describe the scope of the possibilities to generate current functionalized chemical materials using amino acids from biomass instead of fossil resources, thereby taking advantage of the biomass structure in a more efficient way than solely utilizing biomass for the production of fuels or electricity

Pretreatment of Lignocellulosic Wastes to Improve Ethanol and Biogas Production: A Review

Lignocelluloses are often a major or sometimes the sole components of different waste streams from various industries, forestry, agriculture and municipalities. Hydrolysis of these materials is the first step for either digestion to biogas (methane) or fermentation to ethanol. However, enzymatic hydrolysis of lignocelluloses with no pretreatment is usually not so effective because of high stability of the materials to enzymatic or bacterial attacks. The present work is dedicated to reviewing the methods that have been studied for pretreatment of lignocellulosic wastes for conversion to ethanol or biogas. Effective parameters in pretreatment of lignocelluloses, such as crystallinity, accessible surface area, and protection by lignin and hemicellulose are described first. Then, several pretreatment methods are discussed and their effects on improvement in ethanol and/or biogas production are described. They include milling, irradiation, microwave, steam explosion, ammonia fiber explosion (AFEX), supercritical CO2 and its explosion, alkaline hydrolysis, liquid hot-water pretreatment, organosolv processes, wet oxidation, ozonolysis, dilute-and concentrated-acid hydrolyses, and biological pretreatments

Chemical production complex optimization, pollution reduction and sustainable development

The objective of this research is to propose, develop and demonstrate chemical production complex optimization to determine the optimal configuration of chemical plants in a superstructure of possible plants. The Chemical Complex Analysis System is a new methodology that has been developed to determine the best configuration of plants in a chemical production complex based on the AIChE Total Cost Assessment (TCA) for economic, energy, environmental and sustainable costs. All new, energy-efficient, and environmentally acceptable plants using greenhouse gases that can produce potentially commercial products designed with HYSYS were integrated into the chemical complex using the System. The optimum configuration of plants was determined based on the triple bottom line that includes sales, economic, environmental and sustainable costs using the System. From eighteen new processes in the superstructure, the optimum structure had seven potentially new processes including acetic acid, graphite, formic acid, methylamines, propylene and synthesis gas production. With the additional plants in the optimal structure the triple bottom line increased from $343 to$506 million per year and energy increased from 2,150 to 5,791 TJ/year. Multicriteria optimization has been used with Monte Carlo simulation to determine the sensitivity of the optimal structure of a chemical production complex to prices, costs, and sustainable credits/cost. In essence, for each Pareto optimal solution, there is a cumulative probability distribution function that is the probability as a function of the triple bottom line. This information provides a quantitative assessment of the optimum profit versus sustainable credits/cost, and the risk (probability) that the triple bottom line will meet expectations. The capabilities of the System have been demonstrated, and this methodology could be applied to other chemical production complexes in the world for reduced emissions and energy savings. With this System, engineers will have a new capability to consider projects in depths significantly beyond current capabilities. They will be able to convert their company’s goals and capital into viable projects that meet economic, environmental and sustainable requirements

Scoping Studies of Dopants for Stabilization of Uranium Nitride Fuel

Uranium nitride (UN) is considered as nuclear reactor fuel because of, among other reasons, its high uranium density and its high thermal conductivity. Its main drawback is that it relatively easily dissolves in hot water, which is particularly problematic when it is used in water-cooled reactors. One possible remedy to this is to add some corrosion inhibitor as dopant to the UN matrix. A number of dopants have been identified that have the potential to inhibit the dissolution process, and their respective merits have been investigated both by neutronic simulations and dissolution experiments. It is concluded that chromium is the most promising candidate

Hemicellulose biorefineries: a review on biomass pretreatments

Biomass pretreatment (BP) plays a crucial role in a lignocellulose feedstock-based biorefinery (LCFBR) for processing of three major output streams (cellulose, hemicelluloses and lignin) into chemicals and biofuels. BP includes processing of lignocellulosic material (LCM) under aqueous, dilute acid or alkaline media to obtain a cellulosic fraction, which is then fermented to produce bioethanol. Hemicellulose is usually treated as a secondary stream due to lack of efficient fermentation of hemicellulosic sugars to ethanol. This review provides BPs assuming that hemicellulose stream should be integrated in LCFBR as a primary fraction for converting into value-added compounds other than bioethanol. Different LCM treatments are analyzed foreseeing bio-based products possible to obtain from hemicellulose path