Nozzles, jacketed vessels

The batch-operating units consist of only one jacketed, cyhndiical vessel with the necessary nozzles and ports for product inlet and out-... 

This family of filters consist of a vertical pressure vessel with a horizontal filter plate at the bottom. The filtrate from this equipment flows out a nozzle on the bottom of the filter. These devises are usually used for slurries where large amounts of solids are being collected. Variations of this equipment include equipment with removable lower heads for easy cake removal, ability to pressure or vacuum filter, ability to wash the filter cake, an agitator to break-up and rewash the filter cake, and heating or cooling jackets for the whole vessel. The Nutsche filter is the industrial version of the well known laboratory scale Buchner Funnel with the exception that it is designed to operate under either on vacuum or pressure. 

The crystallizer was an agitated vessel with an Inside diameter of 9.0 cm and a volume of about 1 1. It was equlppet with four vertical baffles, a water jacket to keep the solution temperature constant, and a nozzle through which nitrogen gas was Introduced In several experiments to suspend a speed crystal more effectively In the solution. Agitation was accomplished with a 5.0 cm stainless steel marine propeller having three blades driven by a variable speed motor. 

Based on initial heat flow calorimetry studies, a process development engineer must choose the appropriate reactor vessels for pilot plant studies. A pilot plant typically has vessels that range from 80 to 5000 L, some constructed of alloy and others that are glass lined. In addition some vessels may have half-pipe coils for heat transfer, while others have jackets with agitation nozzles. A process drawing for a typical glass-lined vessel is shown in Figure 4. In Sections 3.1.4.1 and 3.1.4.2 we review fundamental heat transfer relationships in order to predict overall heat transfer coefficients. In Section 3.1.4.3 we review experimental techniques to estimate heat transfer coefficients in process vessels. 

A jacketed stainless steel vessel without any sharp comers. Sharp comers facilitate growth/fouling, which is difficult to remove. Standard flanged dish ends are used as a cover with provision for agitation assembly, feed/outlet nozzles, etc. as per the requirement of the process planned. The relevant details are provided in Section 7B.16. 

The details of the design of the reactor will be calculated for each process and these will dictate the capacity of the vessel, the size of the cooling/heating jacket or coil, the speed and type of agitator and baffle, the type of agitator gland, and the size of its drive motor the position, range, and sensitivity of the instruments the size of inlet and outlet nozzles, and the type of valves used in these nozzles. Typical reactors are shown in Fig. 3.2. 

All weldments in a reactor contain high residual stress and, unless they are suitably stress-relieved, they are focal points for environmental cracking. However, the circumferential welds by which nozzles are attached to the vessels are particularly vulnerable. The radius of a dished head also contains residual stress from the forming operation, and the top head is often the first point of failure when volatile species (e.g., traces of hydrogen or ferric chloride) are involved (Fig. 12.5) [7]. External jackets can cause problems, unrelated to the process, that arise from the use of cooling water or steam in the jacket which causes external SCC of the vessel projjer. 

Sprays and droplet streams were frozen by injection into an atmosphere of cold, stagnant air in a stainless steel tube (length 112.5 cm, diameter 15 cm) with an LN2-filled cooling jacket (Fig. 10.2). The droplets were injected into the top of the freezing tower at room temperature and were frozen in cold air at temperatures between 90 and 180 °C in the lower parts of the tower. A gas permeable exhaust segment cormected the freezing tower with the LN2-cooled collecting vessel. The temperature was monitored at the nozzle position, the upper and lower tower position and the vessel [8]. 

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