The Design Report1
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The Design Report
The design report contains all of the information about the design project in consideration. A formal report is required from the design team at the completion of its design work, while informal reports may be useful for internal use of the design team during the evolution of the design project.
The design report documents the details of the designed process, projecting its profitability, and making recommendation to invest or not in the process. The report identifies the key assumptions in the design and their potential impact on the performance of the process and its anticipated profitability.
The design team should view its design report as an opportunity to showcase its most creative engineering efforts for management (Seider et al., 1999).
I. Report Organization
Typical reports are normally included the following sections:
Letter of transmittal:This letter, on professional letterhead, is normally directed to the supervisor who requested that the design work be done.
Title page:In addition to the title the authors and their affiliations are listed, as well as the publication date.
Table of contents:All sections of the report should be listed, including the page numbers on which they begin. All pages in the report, without exception, should be numbered.
Abstract:The abstract is a brief description, in one or two paragraphs, of the design report, its key conclusions, special features, and assumptions. These include projections of the economic measures of profitability and recommendations to management.
Summary:The summary is probably the most important part of the report. (Peters and Timmerhaus, 1991). Its purpose is to give the reader the entire contents of the report in one or two pages. It covers all phases of the design project, but it does not go into details on any particular phase. All statements must be concise and give a minimum of the general qualitative information. The aim of the summary is to present precise quantitative information and final conclusions with no unnecessary details.
Introduction:The introduction states clearly the objectives of the design project. It also contains some or all of the followings: A description of the product to be manufactured, the role of this product in the industry, and its significance in national and international trade. A survey of the methods used in manufacturing this product, including the process being described in this report, giving the raw materials, the principal chemical or physical transformations, by-products, wastes. An explanation of the choice of the production method, production capacity, plant location etc.
Process description:This section provides a description of the proposed process and explains the corresponding process flowsheet. It describes the function of each important equipment item and discusses the reasons for each particular choice.
Process flow sheet and material balances:The proposed flowsheet is drawn. All of the process units are labeled and all of the steams are numbered. In addition, the drawing should contain a material balance table, showing for each numbered stream the flow rate, the composition, the temperature, the pressure, and any other important properties.
Energy balance and utility requirements:This section discusses the energy requirements of the process. All the heating, cooling, and power demands should be identified, along with the method of satisfying these demands, that is the description of the utilities system.
Unit descriptions and specification sheets:Every process unit in the flowsheet is described in terms of its specifications, the design methodologies, the data employed. The important approximations should be discussed, as well as the resulting uncertainties.Specifications sheets are required to guide purchasing agents in locating vendors of desired equipment, and to enable vendors to prepare bids. These sheets provide the design specifications for each of the process units in the process flowsheet, as referred to in the unit description.
Equipment cost and fixed-capital investment:A table is prepared, containing the estimated purchased cost of every equipment item in the process flowsheet, identified according to the label on the flowsheet. The sources of prices should be identified.The fixed-capital investment is presented along with the corresponding estimated method.
Operating cost:The requirements in raw materials, utilities, labor and other are summarized in table format and the corresponding cost is estimated. The working capital could also be estimated in this section.
Profitability analysis:Based on the results of fixed-capital investment and the operating cost estimation, several profitability measures are calculated, e.g., the payback period, the return on investment, the net present value, etc. The methods of estimation should be specified.
Sensitivity analysis:Uncertainty is a crucial characteristic of the design process. It comes from the lack of technical information, or the fussy economic environment. The design team expends considerable effort by locating data in the literature or extract them from experimentation, if possible. In any case a sensitivity analysis is useful to reveal the effect of the most uncertain magnitudes on the crucial technical and economical results of the design process.
Important considerations: Any important for the process matter not included in the other sections could be included in this section.
Conclusion and recommendations:The principal conclusions of the design study should be presented, together with a the recommendations for management.
Acknowledgments:Acknowledges important assistance of others who are not listed as preparing the report, such as industrial consultants, equipment vendors, librarians etc.
Nomenclature:All symbols used in the report are listed together with their meaning and units.
Bibliography:All literature sources referred to in the report are presented.
Appendix:Material and energy balance calculations, together with the equipment sizing calculations, that is the process mathematical model, must be presented, so as to be able to check by any engineering supervisor. The data used in calculations should be summarized, together with their source. Details on any computer software, if used, should be also presented. A systematic presentation of the process design model and the corresponding solution algorithms, proposed by Maroulis and Saravacos (2003), is summarized in Section IV of this chapter.
II. A Design Report Template
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III. General Rules and Recommentations for Preparation of Written reports
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IV. A Systematic Presentation of Process Design Algorithms
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V. Guidelines for Oral Presentations
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REFERENCES
Maroulis ZB, Saravacos GD, 2003. Food Process Design. Marcel Dekker, New York.
Peters MS, Timmerhaus KD, 1991. Plant Design and Economics for Chemical Engineers. McGraw-Hill, New York.
Seider WD, Seader JD, Lewin DR, 1999. Process Design Principles.John Wiley, New York.