What can H2-int do?
- Target minimum hydrogen network consumption on the basis of hydrogen purity
- Target minimum hydrogen network consumption including complete analysis of the network impurity components
- Minimize hydrogen demand through maximizing hydrogen re-use
- Analyze hydrogen purification options
- Select the optimum choice between multiple sources of hydrogen
- Explore the trade-offs between hydrogen flowrate and purity
- Design of hydrogen distribution networks
- Explore options for hydrogen recycle to hydrogen plants
H2-int improves the performance and design of refinery hydrogen networks.
The worldwide trend towards the production of low sulfur and low aromatic gasoline, and diesel and the trend towards processing heavier crude oils places increased demands on refinery hydrogen systems. Meeting the resulting increased demands for hydrogen can require significant capital investment in, for example, steam reformers and compression equipment. Yet, most refinery hydrogen systems are inefficient and have significant room for improvement.
H2-int allows refiners to improve the performance of their hydrogen networks, both to reduce operating costs and to decrease capital investment to meet the new demands.
H2-int allows targets to be set for minimum hydrogen consumption. Targets can be set for hydrogen recovery and hydrogen plant production. Targets also give insights into the effective use of hydrogen purification units.
The assessment of hydrogen resources can be presented in a simple, graphical manner, which gives the engineer insights into process design, sensitivity analysis and operations planning. These graphical targeting methods are complemented by detailed design methods for hydrogen distribution networks that allow practical complexities, such as compression costs and piping costs into the calculations.
H2-int allows detailed analysis of all gas impurities to be carried out. This involves detailed physical property calculations within the consumer and producer units as the optimization is carried out.
Targeting Minimum Hydrogen Consumption with Lumped Impurities
Hydrogen consumers require a specified flowrate of hydrogen with a specified partial pressure at their inlets. In many cases, there are gases leaving the consumers that contain significant amounts of hydrogen.
H2-int can systematically analyze the potential for re-using hydrogen across a refinery based on lumping of the impurities as methane. This analysis is quick and simple and gives a target for the minimum consumption of hydrogen that maintains the consumer demands.
Maximizing the recovery of hydrogen also means that the losses to the fuel or flare systems are minimized. In this way, the use of available hydrogen can be maximized or the production of hydrogen in hydrogen plants minimized. Results are presented in a simple, graphical manner, providing the engineer with insights.
Targeting Minimum Hydrogen Consumption with Detailed Impurity Analysis
Whilst lumping of the impurities as methane is quick, simple and gives insights, it neglects important features of the details of the impurities, such as hydrogen sulfide. H2-int allows a target to be set based on a detailed consideration of all impurity components. This requires detailed physical property calculations in the producer and consumer units.
Network Design (Synthesis)
H2-int carries out the design of the distribution system automatically. The designer maintains control over the network complexity and can impose constraints, such as maximum and minimum flowrates, forbidden connections and compulsory connections. Distribution features and costs associated with pipework and compression are included in the design. Again, the design (synthesis) can be carried out either using lumped impurities or a detailed analysis of the individual impurity components.
Multiple Sources of Hydrogen
Often, there are several possible sources of fresh hydrogen available, for example, a hydrogen plant, catalytic reformers, and imports from chemical plants, such as ethylene processes. Each source can have a different quality, pressure and cost. H2-int is able to select the best mix of supplies in order to satisfy the problem with a minimum cost.
Analysis of Hydrogen Purification Options
The consumption of hydrogen can be decreased by the introduction of hydrogen purification units. The purification units would typically be pressure-swing adsorption or membrane units. The placement of these units within the network is critical. Fundamental principles dictate where such units must be placed to derive the maximum benefit for the network. Indeed misplacement of the units can bring no benefit at all in terms of the overall network.
H2-int allows the designer to determine the optimum type, size and placement of different purifier designs.
Trade-offs Between Purity and Flowrate
Hydrogen networks offer degrees of freedom that in some cases allow trade-offs between hydrogen purity and flowrate. Such opportunities arise from the mixing that takes place throughout the network. H2-int allows these trade-offs to be explored systematically.