Equipment requirements

in order to adequately protect the equipment , the pressure, relief system should limit the pressure in the. reactor (or an associated item of equipment if it has a lower design pressure) to its maximum accumulated pressure. 

For some other types of emergency relief, such as dust explosion relief of relatively weak vessels, it is common practice to size the relief system to limit the pressure to that which will cause deformation but not failure of the vessel. If an explosion occurs, the deformed vessel can be replaced. Great care should be taken before applying such principles to pressure vessels for the following reasons  

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The most common contaminants in produced gas are carbon dioxide (COj) and hydrogen sulphide (HjS). Both can combine with free water to cause corrosion and H2S is extremely toxic even in very small amounts (less than 0.01% volume can be fatal if inhaled). Because of the equipment required, extraction is performed onshore whenever possible, and providing gas is dehydrated, most pipeline corrosion problems can be avoided. However, if third party pipelines are used it may be necessary to perform some extraction on site prior to evacuation to meet pipeline owner specifications. Extraction of CO2 and H2S is normally performed by absorption in contact towers like those used for dehydration, though other solvents are used instead of glycol. 

Finally, under the heading Specific pressure equipment requirements specific requirements are set out for equipment with a risk of overheating, for piping and, last but not least, specific quantitative requirements which set out a series of safety factors for certain pressure equipment. These latter provisions apply as a general rule which means that a manufacturer or a harmonised standard may deviate from these factors if it can be demonstrated that appropriate measures have been taken to achieve an equivalent level of safety. 

First, considerably greater emphasis has been placed on semimicro techniques and their application to preparations, separations, analysis and physical determinations such as those of molecular weight. We have therefore greatly expanded the section on Manipulation on a semi-micro scale which was in the Third Edition, and we have described many more preparations on this scale, some independent and others as alternatives to the larger-scale preparations which immediately precede them. Some 40 separate preparations on the semi-micro scale are described in detail, in addition to specific directions for the preparation of many classes of crystalline derivatives required for identification purposes. The equipment required for these small-scale reactions has been selected on a realistic basis, and care has been taken not to include the very curious pieces of apparatus sometimes suggested as necessary for working on the semi-micro scale. 

The Isasmelt process uses a simple stationary, cylindrical, refractory-lined reaction vessel. The typical blended feedstock to the vessel is of a moist lumpy consistency and this feature greatly simplifies environmental control equipment requirements. 

Fig. 28. Schematic representation of dead-end and cross-flow filtration with microfiltration membranes. The equipment used in dead-end filtration is simple, but retained particles plug the membranes rapidly. The equipment required for cross-flow filtration is more complex, but the membrane lifetime is...

By far the largest proportion of gas sampling operations in industry is carried out for environmental reasons and the sampling methods employed have been thoroughly researched and are well documented (5—12). The preparation, precautions and equipment requirements involved in the sampling of air pollution sources are appHcable to most other gaseous environments (see Airpollution control methods). 

Vacuum equipment requires strength to withstand the pressure of the surrounding atmosphere. The full load is ca 101.3 kPa when the internal gas pressure in the system is sufficiently reduced (see Pumps). 

The second term in brackets in equation 36 is the separative work produced per unit time, called the separative capacity of the cascade. It is a function only of the rates and concentrations of the separation task being performed, and its value can be calculated quite easily from a value balance about the cascade. The separative capacity, sometimes called the separative power, is a defined mathematical quantity. Its usefulness arises from the fact that it is directly proportional to the total flow in the cascade and, therefore, directly proportional to the amount of equipment required for the cascade, the power requirement of the cascade, and the cost of the cascade. The separative capacity can be calculated using either molar flows and mol fractions or mass flows and weight fractions. The common unit for measuring separative work is the separative work unit (SWU) which is obtained when the flows are measured in kilograms of uranium and the concentrations in weight fractions. 

Heat Sensitivity. The heat sensitivity or polymerization tendencies of the materials being distilled influence the economics of distillation. Many materials caimot be distilled at their atmospheric boiling points because of high thermal degradation, polymerization, or other unfavorable reaction effects that are functions of temperature. These systems are distilled under vacuum in order to lower operating temperatures. For such systems, the pressure drop per theoretical stage is frequently the controlling factor in contactor selection. An exceUent discussion of equipment requirements and characteristics of vacuum distillation may be found in Reference 90. 

All but the very simplest equipment suites contain multiple process units. The minimum number of process units is one for each type of processing equipment required to make a batch of product. However, many equipment suites contain multiple process units of each type. In such equipment suites, multiple batches and multiple production runs can be in progress at a given time. 

Equipment Costs The cost of dehvered equipment forms the basis of most methods of estimating the fixed-capital cost. The equipment required can usually be divided into (1) processing equipment, (2) equipment for handling and storage of raw materials, and (3) finished products handling and storage equipment. 

Disadvantages of these continuous countercurrent systems are associated primarily with the complexity of the equipment required and with the attrition resulting from the transpoiT of the ion exchanger. An effective alternative for intermediate scale processes is the use of merry-go-round systems and SMB units employing only packed-beds with no movement of the ion-exchanger. 

Equipment and Accessory Requirements The types and amounts of equipment required v aiw with the capacity of the station and its function in the vv aste-management system. Specifically, truck... 

Equipment requirements. The types of equipment that have been used at sanitary landfills include both crawler and rubber-tired trac tors, scrapers, compactors, draghnes, and graders. The size and amount of equipment required will depend primarily on local site... 

Equipment requirements Vary with size of landfills. 8 to 10 h/day. 

The use of impedance electrochemical techniques to study corrosion mechanisms and to determine corrosion rates is an emerging technology. Elec trode impedance measurements have not been widely used, largely because of the sophisticated electrical equipment required to make these measurements. Recent advantages in micro-elec tronics and computers has moved this technique almost overnight from being an academic experimental investigation of the concept itself to one of shelf-item commercial hardware and computer software, available to industrial corrosion laboratories. 

Equipment—client may not have the equipment required to manufacture a specific product. It may be that available capital and installation time are limited such that they simply can not design, acquire, install and test the process equipment to reach the desired capacity within the available budget and time. If a product is in the early stages of its life cycle, the capital required may be hard to justify. This could be based upon the low initial volume anticipated while developing the market or the need to take advantage of a time-sensitive business opportunity. Tolling can provide a means to safely produce introductoiy, short-term, or small volume products that would otherwise be uneconomic. 

Any special equipment requirements, including that needed for charging or handling highly hazardous materials... 

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