代做Utility System Design 2024–2025代做留学生Matlab编程

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Utility System Design 2024–2025

Coursework

Release: 11/11/2024

Submission: 16/12/2024

Coursework value: 30%

Introduction

The purpose of the coursework is to provide you with an opportunity of demonstrating the application of knowledge acquired in the course to a larger scale industrially related problem. You will make use of knowledge gained in lectures, problem solving, and computer-based practicals (including available Guides), and apply it to produce a feasible, validated utility system.

You have a certain period of time to produce the coursework. You will also be expected to apply your own background skills as Chemical Engineers.

You will be expected to produce an appropriately structured, written, and presented report, with a limited number of pages. You are provided with some guidance in relation to the structure of the report to be produced, but part of the assessment is to evaluate your skills in reporting the work that you have performed, its validity, and relevance.

The coursework is group based – with groups comprising three members. You are required to choose the members of the group and register the group and members in Blackboard. Marks are awarded for group contributions and for individual contributions. For group contributions, all members of the group are awarded the same mark. Individual contributions are to be labelled with the member making the contribution.

Overall Requirements

You are first required to build and simulate the existing operating conditions of a Utility System, as illustrated in Figure 1, using the STAR v153 software (group task).

The second task is to optimise the Utility System, with the objective of minimising the operating costs (group task). You are then required to compare the optimal Utility System with the original Utility System.

Finally, the third task (individual task) is to modify and simulate the original Utility System (not the optimal Utility System) in order to evaluate improvements in heat/power recovery in parts of the existing utility system and so make more effective use of fuel or existing equipment. Each member of the Group will be required to undertake one of the three modification tasks (different task each member). After you have implemented the changes, you are required then to compare these overall changes on the utility system to the original Utility System.

Figure 1: Flowsheet of the Utility System

Legend:

B = Boiler

GT = Gas Turbine

HRSG = Heat Recovery Steam Generator

ST = Steam Turbine

L = Letdown station

P = Process (Steam User)

SG = Steam Generator

De-A = Deaerator

Utility System Data

There are some missing flowrate values in the Utility System in Figure 1 which you need to determine before you start inputting the data to STAR. Site Configuration data should be left as default values. Other relevant information is provided in the tables below. Current flowrate data are required for simulation purposes while minimum and maximum flowrate data are needed for optimisation purposes. Some values, for example turbomachinery power, can only be determined by the actual simulation of the utility system.

Table 1: Fuel data

Fuel LHV Price

Natural Gas (NG) 36,000 kJ Nm–3 0.2 $ Nm–3

Fuel Oil 40,000 kJ kg–1 0.6 $ kg–1

Table 2: Boiler data

Boiler	Fuel	Current Flowrate (kg s–1)	Minimum Flowrate (kg s–1)	Maximum Flowrate (kg s–1)	Efficiency (%)	Blowdown (%)
Boiler 1	NG	80	0	100	90	2
Boiler 2	NG	90	0	110	85	3
Boiler 3	Fuel Oil	120	0	120	75	5

Table 3: Gas Turbine data

Type Fuel Shaftwork (MW) Casing Losses (%)

GT Industrial-based correlation NG 110 0

Table 4: Heat Recovery Steam Generator data

Fuel

Current Flowrate (kg s–1)

Minimum Flowrate (kg s–1)

Maximum

Flowrate

(kg s–1)

Efficiency

(%)

Blowdown

(%)

HRSG

To be

determined

Same as current

Table 5: Steam Turbine general data

ST	Configuration	Shaftwork model	Isentropic Efficiency (%)	Mechanical Efficiency (%)	Power Correction Factor
ST1	Generator	Constant isentropic efficiency	85	97	1
ST2			85
ST3			80
ST4			75

Table 6: Steam Turbine flowrate data

	Current Flowrate (kg s–1)	Minimum Flowrate (kg s–1)	Maximum Flowrate (kg s–1)
ST1
Inlet	180	0	200
Outlet HP	50	0	200
Outlet MP	130	0	200
ST2
Inlet	100	0	120
Outlet	100	0	120
ST3
Inlet	70	0	100
Outlet LP	30	0	100
Outlet Cond	40	0	100

ST4
Inlet	80	0	100
Outlet	80	0	100

General Guidance

It is worthwhile to have looked at the released Practicals and familiarized yourself with the STAR software before attempting this task. There may be items required that are not mentioned in the Guides. Use the Help system to assist in these cases. As the STAR software is frequently updated, some of the screenshots may not correctly reflect what you see on screen. However, the information you require for simulation and optimisation is clearly provided.

Creating the initial model and simulation of the Utility System can be time consuming. Work as a group to discuss and overcome these obstacles. The software will indicate frequently, when you select simulation, that values have not been provided or there are not enough degrees of freedom to perform the task. This means that so many values are fixed it is impossible for the software to calculate appropriate values for those that are missing. Also note that you may have too many degrees of freedom, e.g., there are too many unknowns and the software cannot calculate the missing values.

Consequently, it is suggested that you build up the Utility System flowsheet step-by-step, and simulate each step before progressing to the next. For example, input the steam headers, link them by letdown stations, add a steam generator and then simulate. Then add a process load and simulate again. This way it is easier to resolve smaller problems.

When you have modelled and simulated the Utility System, you then need to optimise it. Within the Steam Network Environment in STAR there are Optimisation options. You should optimise the system by minimising the operating costs. When you have simulated and optimised the original Utility System, then individual member tasks should be performed using the original Utility System as the starting point of the modifications.

Individual Member 1 Task

A senior utility engineer is proposing to increase the overall steam generators’ efficiency. All steam boilers and the HRSG undergo a blowdown where heat (in the form of saturated water) can be recovered to raise additional steam. Use this strategy to reduce the overall fuel consumption by modifying the utility system. Model and simulate the modified system and then compare with original Utility System (simulated).

Individual Member 2 Task

The utility system manager is looking at exploiting the potential of the GT/HRSG system. There is an opportunity to implement supplementary firing and to increase the temperature of the exhaust gases entering the HRSG to 850°C, thus raising additional steam. Use this strategy to reduce the overall fuel consumption by modifying the utility system. Model and simulate the modified system and then compare with original Utility System (simulated).

Individual Member 3 Task

Planned maintenances will reduce HP steam use by 20%, MP steam use by 30% and LP steam by 45%. The technical director of the utility system believes that this an excellent opportunity to shut down the low-efficient fuel oil-fired boiler, however the load on the NG- fired boilers could be increased if necessary. Use this strategy to reduce the overall fuel consumption by modifying the utility system. Model and simulate the modified system and then compare with original Utility System (simulated).

Marking Scheme and Report Submission

It is up to you to decide the exact format of your report and what should be included to support the work you have done. A marking scheme and marking sheet will be made available for reference to help you with this. However, the report should include the following sections:

• Introduction, Aims and Objectives (Group - maximum 5 marks)

• Methodology (Group - maximum 5 marks)

• Original simulation results and main features of the utility system (Group - maximum 30 marks)

• Optimisation and features of the optimised system (Group - maximum 15 marks)

• Member 1 Task modification and simulation (Individual - maximum 30 marks)

• Member 2 Task modification and simulation (Individual - maximum 30 marks)

• Member 3 Task modification and simulation (Individual - maximum 30 marks)

• Conclusions (Group - maximum 5 marks)

Marks are also awarded for the presentation of the report (Group - maximum 10 marks). Total is 100 marks maximum per group member.

As the space is limited, present the information that you think is relevant and reflects the work that has been done and the points that you are attempting to make to an audience. Not all information can be presented as space is not sufficient. Part of the skill is deciding what is relevant and how to express it. Do not be verbose.

You will need to include graphics from STAR (the simulated and optimised flowsheet). You may also want to produce a schematic of the type shown in Figure 1. The most relevant results (again up to you to decide) should be presented in your own Tables. These should include information about the steam headers, fuels, boilers, gas turbines, heat recovery steam generators, steam turbines, vents, letdown stations, etc.

The report should be completed in MS Word, and should not contain more than 24 pages (plus an additional page for the front cover). Pages above this limit will be penalized by a reduction of 5% per additional page in your overall mark.

Late submission of the coursework will also result in a penalty of a reduction in your overall mark. The later the submission the larger the reduction! The reduction is set by the University’s policy. If you have any mitigating circumstances that would result in a late submission, follow the appropriate policy. Note as this is Group based work there are no extensions for DASS students.

In addition, a pdf version of the report should be produced and it should be uploaded to Blackboard. There will be an area in the Utility System Design Blackboard space for this and appropriate instructions a week prior to the submission date. The submitted report in Blackboard will be checked by TurnitinUK for plagiarism and collusion. Be warned!