Chemical plant processes

For most chemical plants, process steam is used at pressures of 1.825 MN/m" (250 psig), saturated or lower. When combined heat and power generation is economically justified, the steam may be generated at about 5.96 MN/m" (850 psig) appropriately superheated and used to drive back-pressure steam turbines passing out process steam at the required pressure level. 

Also, refinery operations and particularly chemical plant processes tend to be unique, so that techniques described in this book do not necessarily apply in all cases. The presentation of material is therefore not meant to be an endorsement, either by the author or publisher, nor are any guarantees, either explicit or implicit made for designs based on the information provided in this book. 

The intent of this Guidelines book is to provide the principles for the evaluation of chemical reactivity and for use of this information to design and operate safer chemical plant processes. Special emphasis is placed on the use of state-of-the-art methodology in the areas of theory, testing methods, and applications in design and operation of inherently safer processes. 

Sanders, Roy E., Human Factors Case Histories of Improperly Managed Changes in Chemical Plants, Process Safety Progress 15 no. 3, Fall 1996 pp. 132-39. 

It is assumed that chemical plant process workers will operate the production facilities as they will replace plants traditionally operated by them. Assuming that operators will not be expected to walk more than 200 yards from the control room, the control rooms will have to be spaced 400yards apart that is, one per 33 acres. Over 750 control rooms will be required for a million pounds per year operation. Building costs will therefore be much higher that on a conventional plant, and may well make the new process uneconomic, especially now that control rooms are being made stronger than in the past. 

Many of the chemical terms in this book are so outdated you may not understand them. If you don t already have GRANDDAD S WONDERFUL BOOK OF CHEMISTRY, get one. It has a dictionary of over 2500 definitions and synonyms of vague and old-fashioned terms for chemicals, plants, processes, etc. 

Visual external inspections (or in-service inspections) should be made regularly to operating vessels to help ensure the integrity of the vessel. The frequency of this inspection should be site-specific, between semiannually and once every three years for most chemical plant processes, depending on the aggressiveness of the chemical plant atmosphere. However, API 510 will accept intervals up to once every five years. 

Do not use ferritic stainless steels containing more than 16% chromium in the 750 F to 1,000 F temperature zone. They invariably embrittle, because of precipitation of a chromium-rich constituent. Even the 11 to 13% chromium alloy sometimes seems to embrittle in this way, for reasons not clear. Unfortunately, this is a common temperature zone for many refinery and chemical plant processes. These ferritic stainless steels should not be used above 1,000°F, either. They will embrittle for a somewhat different reason the formation of an iron-chromium intermetallic compound called sigma phase. 

Lange, H. B. Investigating Chemical Plant Process Variables, Ckem. Eng. Progr., 63(6) 304 (1957). 

The hazard for the chemical plant process is uncontrolled release of toxic chemicals. Accordingly, the system-level constraints are that ... 

Ehrfeld, W. (2004) Process Intensification Through Microreaction Technology in Re-Engineering the Chemical Plant Process Intensification (eds A. Stankiewicz and J.A. Moulijn), Marcel Dekker Inc., New York pp. 177-200. 

Begin to be widely used to treat chemical plant process and waste streams... 

Most chemical plant processes are complex. Materials of construction for process equipment and piping must be selected with care to assure corrosion-free operation of those plants. In a well designed plant, materiids selection is based on a number of factors prior service history, field in-plant corrosion tests, pilot plant corrosion tests and laboratory corrosion tests, in that relative order of usefiihiess. often, actual service history regarding materials performance is not available because plants kept poor records, plant personnel were not trained to evaluate corrosion failures, or, in the case of new processes, because there is no service history. The same can be said for field in-plant corrosion tests. Pilot plant testing is usually the best alternative in such cases, but such facilities are typically operated only for short runs and are not well suited for gathering long-term corrosion performance data. 

Industrial and chemical plant process equipment involving exposure to a wide variety of organic and inorganic chemicals. 

A chemical plant process requires that a cylindrical reaction tank be filled with a certain liquid in 238 s. The tank is 1.2 m in diameter and 4.6 m high. What flow rate in liters per minute is required to fill the reaction tank in the specified time ... 

Moore, F. and Rukovena, E, Chemical Plants + Processing, European Edition, August 1987, p. 11. 

Norman P. Lieberman is a chemical engineer with 50 years of experience in process plant operation, design, and field troubleshooting. An independent consultant, he troubleshoots oil refinery and chemical plant process problems and prepares revamp designs. Mr. Lieberman teaches 20 seminars a year on "Troubleshooting Process Plant Operations" and has written eight books on plant process operations and problems. 

Elizabeth T. Lieberman is a chemical engineer with more than three decades of experience in the process industries. She works as a consultant troubleshooting oil refinery and chemical plant process problems. Ms. Lieberman also has experience in ceramic clay processing, refractories processing, and the conveyance of slurry flow. 

---