Umer Zahid

• PhD Chemical Engineering
• King Fahd University of Petroleum and Minerals

Plastic waste has become a pressing global environmental issue as production and disposal rates surge worldwide. Most plastics are non-biodegradable and accumulate in landfills and the natural environment, posing severe ecological risks. Meanwhile, energy demand continues to escalate rapidly due to population and economic growth. Dependence on foss...

Many chemical engineering programs teach gas permeation because of its important applications in the oil and gas industry. In fact, it is considered a good replacement for classical separation techniques such as cryogenic technologies, PSA, physical and chemical absorption etc. Gas permeation module modeling can play an important role in both simul...

The anthropogenic emission of greenhouse gases (GHGs), especially CO2, is becoming an economic and societal challenge globally. CO2 utilization in a closed loop is an essential approach for reducing its greenhouse effects and regulating environmental pollution in a cost- and energy-effective way. On this frontier, chemicals and fuels can be produce...

Plastic waste is a problematic issue impacting the environment and human health. A proper recycling of plastics to valuable products is highly needed to meet the increase in energy demand. Plastics have high heating value; therefore, the thermochemical recycling of plastic waste is a valid and feasible approach. Recently, ethanol has attracted wide...

The reliance on natural gas as a fossil fuel often overshadows its potential for clean energy transformation. In contrast with the steam methane reforming (SMR) process, renowned for its substantial CO2 emissions, methane pyrolysis (MP) stands out for its capability to produce hydrogen without any accompanying CO2 byproducts. Additionally, MP prese...

The global annual production of plastics and tires exceeds 6.5 billion tons, with only 10% being recycled, leading to significant environmental problems. Thermochemical gasification of these waste materials offers a potential avenue for producing renewable hydrogen while harnessing underutilized carbon-based waste streams. This review highlights...

The increasing global population is expected to drive a surge in fertilizer demand in the future. However, traditional ammonia-urea production methods, such as steam methane reforming (SMR), contribute significantly to greenhouse gas (GHG) emissions. The purpose of this study was to mitigate CO2 emissions during an unbalanced plant load of ammonia...

The release of toxic hydrogen sulfide gas from subsurface oil wells during oil and gas drilling operations leads to serious health and safety problems for both the drilling structures and working personnel. The implementation of controls and mitigation techniques is vital to abating the high health and economic risks associated with H2S exposure. T...

Exposure to hydrogen sulfide (H2S) can result in severe health and safety issues for workers and the drilling structures, leading to significant economic burden. It is crucial to implement measures to control and mitigate the risks of H2S exposure and remove it in-situ during drilling operations. Additionally, drilling operations can be made more e...

Graphene has recently emerged as an attractive material for various applications, including water decontamination. However, the pristine graphene oxide (GO) usually provides unsatisfactory adsorptive removal of water pollutants. GO reduction, whether chemically or thermally, has the potential to enhance its adsorption performance, particularly towa...

Adsorption is an attractive process for wastewater treatment due to its simplicity and mild operating conditions. However, the efficacy of this process depends on the development of effective adsorbents. Layered double/triple hydroxides (LDHs/LTHs) are promising materials for the adsorptive removal of water pollutants. In this study, the one-facto...

The technology of the membrane has garnered significant interest and attention in the separation processes of modern industries. This is because of efficient high energy, environmental compatibility, continuous operation process, and minimal investment capital. The polymeric membrane-based gas separation has widely been applied industrially in area...

The worldwide demand for energy is increasing significantly, and the landfill disposal of waste tires and their stockpiles contributes to huge environmental impacts. Thermochemical recycling of waste tires to produce energy and fuels is an attractive option for reducing waste with the added benefit of meeting energy needs. Hydrogen is a clean fuel...

This study has been dedicated towards the conversion of plastics to methanol and hydrogen. The base design (case 1) represents the conventional design for producing syngas via steam gasification of waste plastics followed by CO2 and H₂S removal. The syngas then processed in the methanol synthesis reactor to produce methanol, whereas, the remaining...

The present work discusses the development and application of a machine-learning-based model to predict the enthalpy of combustion of various oxygenated fuels of interest. A detailed dataset containing 207 pure compounds and 38 surrogate fuels has been prepared, representing various chemical classes, namely paraffins, olefins, naphthenes, aromatics...

In the present work, artificial neural networks (ANN) has been used for developing a comprehensive model for predicting flash point (FP) of petroleum fuels containing the following oxygenated chemical classes: alcohols, ethers, aldehydes, ketones and esters. 474 pure compounds and 314 blends comprising of various compounds were used for model devel...

The global energy demand is expected to increase by 30% within the next two decades. Plastic thermochemical recycling is a potential alternative to meet this tremendous demand because of its availability and high heating value. Polypropylene (PP) and polyethylene (PE) are considered in this study because of their substantial worldwide availability...

With the increase in the global energy requirements, the utilization of fossil fuels have been also increased which not only increased greenhouse gas (GHG) emissions but also caused global warming. The sharp reduction in the GHG emissions demands for utilizing the energy mix and fuel switch technologies to develop the cleaner fuels. In this study,...

Syngas is an important intermediate feedstock to produce various downstream chemicals and clean fuels. In this study, two process models are developed by integrating the gasification and dry-reforming models in the parallel and series configuration to produce the syngas at the rate of 10,000 kmol/h with H2/CO ratio of 2. The heat integration is als...

Global carbon emissions are continuously increasing, clean and sustainable technologies are needed to utilize fossil fuels. Methanol is a clean fuel that can enable a smooth transition between fossil fuels and renewables. This work explored the production of methanol through two different fossil fuels, i.e., natural gas (case I) and vacuum residue...

The continuous rise of global carbon emissions demands the utilization of fossil fuels in a sustainable way. Owing to various forms of emissions, our environment conditions might be affected, necessitating more focus of scientists and researchers to upgrade oil processing to more efficient manner. Gasification is a potential technology that can con...

Carbon dioxide (CO2) has become a primary atmospheric greenhouse gas that has stirred up numerous energies and environmental-related mishaps around the world. Its unwelcome contribution to the decay of the global ecosystem has generated alarming concerns. Therefore, it has triggered an urgent need to design reliable methods for capturing and conver...

This study proposes an onboard membrane carbon capture and liquefaction system for LNG-fueled ships to satisfy the IMO’s 2050 greenhouse gas reduction targets. The exhaust gas from a natural gas ship has a low CO2 fraction (∼3%) and high O2 fraction (∼16%) compared to the flue gas from power plants. Herein, considering the above distinguishing feat...

The continuous rise of global carbon emissions demands the utilization of fossil fuels in a cleaner and sustainable way. Gasification is a potential technology that can convert the dirty fossil fuels for the production of clean and environment friendly fuels in an economical manner. In this study, vacuum residue is employed as a feedstock to produc...

Increased energy demand in recent decades has resulted in both an energy crisis and carbon emissions. As a result, the development of cleaner fuels has been under the research spotlight. Low-rank coals are geographically dispersed, abundant, and cheap but are not utilized in conventional processes. Syngas can be produced from coal-using gasificatio...

Syngas is an important intermediate feedstock to produce various downstream chemicals and clean fuels. In this study, two standalone process models are first developed to produce syngas from coal gasification and natural gas dry reforming which provide the results for benchmarking the conceptual design. Two process models are then developed by inte...

A comparison study between conventional and PdAu-based membrane steam methane reforming (SMR) processes for small-scale hydrogen production was conducted. Both processes were simulated using a commercial simulation software Aspen Plus. For the PdAu-based membrane reactor, a 1D pseudo-homogenous model was developed via Aspen Custom Modeler (ACM). Th...

With the increase in global energy requirements, the utilization of fossil fuels has also increased, which has caused global warming. In this study, a process integration framework based on an energy mix system is proposed to simultaneously produce two cleaner fuels (methanol and H2). Aspen Plus is used to develop process models followed by their t...

The aim of this study was to evaluate a perovskite catalyst for use as a carbon-resistant catalyst in methane dry reforming. The oxygen-rich ABO3+δ (CeCoxNi1-xO3+δ) perovskite was selected for this investigation due to its crystalline nature and ability to accommodate a wide range of cations; perovskites notably possess catalytically advantageous o...

Understanding of the flow field and heat transfer in a boiler is important to meet with the often-conflicting objectives of efficient steam generation, safe operation and minimization of pollutant emissions. Steam generation requires high gas temperatures, which often lead to high NOx emissions. High gas temperatures inside the boiler may also lead...

Hydrogen produced from renewable resources has been gaining attention and its use is encouraged, as an effort of emission control. Consequently, the development of hydrogen production methods allows for fuel cell technologies to be developed in parallel. As a clean system for generating electricity, the reaction between hydrogen and oxygen occurrin...

Liquid hydrogen is gaining increasing attention owing to its high energy density as 10.1 MJ/L compared to gaseous hydrogen as 5.6 MJ/L at 700 bar. However, the energy required for its cryogenic processes is significant. To reduce this energy demand, liquefied natural gas (LNG) cooling was introduced in addition to a nitrogen refrigerant to the hydr...

Toluene diisocyanate (TDI) is an important raw material to produce a flexible polyurethane foam, and the demand for TDI is growing as the polyurethane market is driven by high demand. The cold phosgenation reactor plays a vital role in the production of TDI, in that the overall reaction selectivity is determined and the most of by-product urea, whi...

Methanol is a clean fuel and an important feedstock for the petrochemical industry. Conventionally, the coal-to-methanol process generates a substantial amount of CO2 emissions with a low yield of methanol. In this study, we propose the conceptual design development of coal-to-methanol process using captured CO2 from the gasification plant by imply...

Methanol production has gained a lot of attention due to its wide application in both the process and product industries. This study aims to investigate the coal/methane based process for simultaneous methanol and power generation. Two process models were developed in Aspen Plus and techno-economically compared. Case 1 is taken as a base case model...

Acid gas removal (AGR) is a critical step in the supply chain of natural gas for its safe transmission and clean combustion. Chemical amines are the most commonly employed commercial solvents for the gas cleaning. Due to energy intensive nature of the AGR process, ways to improve process efficiency are vital. This study investigated the removal of...

In the present chapter, we study the industrially relevant system containing acetic acid and water. Indeed, vapor-liquid equilibrium data for this mixture are correctly predicted and compared to their counterpart obtained from the relevant literature as well as from the ubiquitous commercial process simulator: Aspen-HYSYS. In addition, we carry out...

Piping and instrument diagrams (P&IDs) are a key component of the process industry; they contain information about the plant, including the instruments, lines, valves, and control logic. However, the complexity of these diagrams makes it difficult to extract the information automatically. In this study, we implement an object-detection method to re...

Most of the industrial acid gas removal (AGR) units employ chemical absorption process for the removal of acid gases from the natural gas. In this study, two gas processing plants operational in Saudi Arabia have been selected where two different amines n1amely, diglycolamine (DGA) and monoethanol amine (MDEA) are used to achieve the sweet gas puri...

Acid gas cleaning is one of the natural gas processing steps where the acid gases are removed to satisfy the quality of the sweet gas. Conventionally, this is achieved by processing the sour gas through an acid gas removal (AGR) unit to produce the desired sweet gas, while concentrating the H2S gas in the acid gas enrichment (AGE) unit. Together wi...

Acid gas cleaning is one of the natural gas processing steps where the acid gases are removed to satisfy the quality of the sweet gas. Conventionally, this is achieved by processing the sour gas through an acid gas removal (AGR) unit to produce the desired sweet gas, while concentrating the H2S gas in the acid gas enrichment (AGE) unit. In this stu...

With an increasing focus on energy performance improvements and strict environmental laws, there is a need to recycle water resources and reuse them in the industry. Refineries consumes huge amounts of water which offer an opportunity to reprocess it in an efficient manner. This study focusses on the design and simulation of sour water stripping (S...

IGCC is a pre-combustion technology that can be effectively used to produce both hydrogen and electricity while reducing the greenhouse gas (GHG) emissions. Two process models are developed in Aspen Plus ® software and are compared techno-economically. The conventional design of IGCC process is taken as case 1, whereas, case 2 represents the concep...

This study is focused on the production of syngas using gasification and dry methane reforming (DMR) technologies. The two processes are compared as a standalone design for a syngas production capacity of 10,000 kmol/h with H2 to CO ratio of 0.88. The two processes are then integrated to develop a novel design that can reduce the CO2 emissions to a...

Integrated gasification and combined cycle (IGCC) is a pre-combustion carbon capture technology that can be used to generate electricity and hydrogen while reducing the green house gas emissions. In this study, three IGCC based process models are developed in Aspen Plus ® followed by their techno-economic evaluation. Case 1 is the conventional IGCC...

This study focusses on the design and simulation of sour water stripping (SWS) unit in the refinery setup for the reuse of sour water. In this study, process simulation has been performed to analyze the energy saving and cost reducing prospects in the sour water stripping unit. First, a base case design has been simulated using a reference sour wat...

Dehydration is a common step employed before the transmission of natural gas and/or carbon dioxide in order to avoid hydrate formation. This study is focused on the simulation of dehydration process for the natural gas and CO2 stream using triethylene glycol (TEG) solvent as the dehydrating agent. This study relates the experiences from the natural...

Conventional natural gas sweetening processes are mainly focused on the H2S removal with the bulk removal of CO2. However, the placement of natural gas processes within the carbon capture and storage (CCS) framework provides an opportunity to achieve the synergies between the two technologies. The purpose of this study is to investigate the CO2 cap...

Carbon capture and storage (CCS) is one of the dominant technologies to tackle the global warming issue. The transport of CO2 for geological storage is economically feasible by ship when the storage site location is off-shore and instalment of an off-shore pipeline requires a huge capital cost. Ship transportation requires the captured CO2 to be in...

Carbon capture and storage (CCS) is one of the dominant technologies to tackle the global warming issue. The transport of CO2 for geological storage may become economically feasible by ship when the storage site location is off-shore and installment of an off-shore pipeline requires a huge capital cost. Ship transportation requires the captured CO2...

Carbon capture and storage (CCS) is one of the dominant technologies to tackle the global warming issue. The transport of CO2 for geological storage is economically feasible by ship when the storage site location is off-shore and installment of an off-shore pipeline requires a huge capital cost. Ship transportation requires the captured CO2 to be i...

Techno-economic assessment of integrating coal gasification and methane reforming processes with CO2 capture.

Enhanced coal bed methane recovery (ECBM) process is an important developing technology because of its dual advantage, i.e., producing methane gas and sequestering CO2 at the same time. CO2 have been used for enhanced oil recovery (EOR) for more than five decades but available storage sites for EOR are only limited to oil rich countries. Pakistan h...

Process monitoring and fault diagnosis using the multivariate statistical methodologies has been extensively used in the process and product development industries for the last many decades. The fault in one process variable readily affects all the other associated variables which not only makes the fault detection process more difficult but also t...

Conventional natural gas sweetening processes are mainly focused on the H2S removal with the bulk removal of CO2. However, the placement of natural gas processes within the carbon capture and storage (CCS) framework provides an opportunity to achieve the synergies between the two technologies. The purpose of this paper is to investigate the CO2 cap...

Multivariate statistical methods for process monitoring are attaining a lot of attention in chemical and process industries to enhance both the process performance and safety. The fault in one process variable readily affects the other variables which makes it difficult to identify the fault variable precisely. In this study, principal component an...

IGCC is a power generation technology which represents a higher thermal efficiency with large scale implementation of CO2 capture. In this study, two IGCC process models have been evaluated in terms of both the process performance and economics with CO2 capture. Case 1 is based on the conventional IGCC process, whereas, case 2 presents an idea of i...

Power producing industry has largely relied on coal as a fuel source and will continue to depend on it for coming decades. However, to address the global warming problem while keeping high efficiency and economic feasibility of the processes is a key challenge. Coal-based power plants with post-combustion capture tend to have lower capital costs an...

With recent advancements in the carbon capture and storage (CCS), much interest has been developed in the CO2 transport options. In this paper, various aspects associated with the performance and safety of CO2 transportation are reviewed and discussed. The operational range for pipeline and ship transportation of CO2 is quite different, with both m...

With recent advancements in the carbon capture and storage (CCS), much interest has been developed in the CO2 transport options. An infrastructure including pipelines, ships, tanker truck and railways will be collectively required for a large scale CO2 transport network. In particular, ship transportation can play a special role in the early phase...

Torrefaction reactor model is required for the development of reactor and process design for biomass torrefaction. In this study, a one-dimensional reactor model is developed based on the kinetic model describing volatiles components and solid evolution and the existing thermochemical model considering the heat and mass balance. The developed react...

Carbon capture and storage (CCS), a key technology for addressing global warming is in between demonstration to commercialization phase. Transportation of CO2 is required since storage sites are not necessarily present under the source sites. Ships can be used for long distance transport of CO2; liquefaction being a vital component in ship transpor...

Carbon capture and storage (CCS) is a key technology for addressing global warming by capturing carbon dioxide and storing it somewhere, usually underground. The transportation of CO2 is required since storage sites are not necessarily present near the source sites. Ships can be used for long distance transport of CO2. However, CO2 sources are not...

The continuous rise of CO2 emissions is a major cause of global climate change. Carbon capture and storage (CCS) is widely seen as a practical technology for reducing CO2 emissions. CCS mainly consists of capturing CO2 from large emitting sources and its transportation to a sequestration site where it can be stored safely for a long period of time....

Concerns about the continuous increase of pollution caused by use of fossil fuel make biomass as one of the promising renewable energy source. However, the inconvenient properties of the biomass including low calorific value, high oxygen contents, tenacious structure, hydrophilic nature and high moisture contents limit its use as a fuel. The biomas...

Carbon Capture and Storage (CCS) is considered as one of the most practical approaches for the reduction of CO2 emission. If CCS is applied to low carbon power generation, its deployment will require the construction of CO2transport infrastructure on a massive scale. Because of its cost, estimated at many billions of dollars, decision makers who se...

The average CO 2 emission growth rate of Korea is 1.4% which is second highest among OECD countries. The Korean government plans to start CO 2 injection by 2018, so in order to develop ready to inject sequestration site by that time, there is a need to assess storage sites technically, economically, and from safety point of view. Three potential ba...

CO2 can be stored in geological media for hundreds to thousands of years depending on the location and trapping mechanism(s) involved. A saline aquifer presents the largest capacity available for CO2 storage among all geological storage options. Two main methodologies proposed by the Department of Energy, US (DOE) and carbon sequestration leadershi...