Tank/Drum reactor

Compared with the rotating-drum reactor, the stirred-tank reactor is easy to operate, and the aggregation of substrate to form particles can be avoided. Because the substrate is quite wet, the energy consumption for agitation is generally high added to which the stirred tank reactor is hard to isolate completely from the environment and, therefore, contamination may occur. 

Nickel is a hard, grey-white metal, malleable, and resistant to corrosion when exposed to air. Slowly attacked by dilute hydrochloric and sulphuric acid and readily attacked by all concentrations of nitric acid. It is particularly resistant to concentrated sodium and potassium hydroxide and is therefore often used for vessels which contain them. There are several commercially produced grades of nickel which, although expensive, may be fabricated easily they are used in the construction of pumps, pipes, and fittings, valves, heating coils, drums, tanks, and reactors, and components for glass-lined vessels. It is also used extensively for nickel plating and in alloys, particularly Monel metal and stainless steels. 

The reactor tank is a cylindrical vessel of 15 m height and 4.8 m inner diameter, manufactured from stainless steel. The reactor tank wall thickness is 20 mm. Inside the tank a reactor coolant flow guiding structure of 1.6 m diameter is installed, with a lower inlet chamber at the bottom below the core and connections to hot legs at the top. In the upper part of the reactor tank, primary heat-exchangers are installed and fixed on a support frame on which there are also drums for spent fuel storage. Water circulation in the reactor tank is natural without boiling. The reactor tank is installed in a concrete cavity lined with carbon steel, 20 mm in thickness. The inner diameter of the reactor cavity is 5.2 m, and its height is 16 m. The reactor pool is covered by a lid sealed with a hydroseal. 

Pressure relief equipment includes relief valves, safety valves, rupture discs, piping, drums, vent stacks, pressure indicators, pressure alarms, pressure control loops, and flare systems. Pressure relief devices can be placed on pumps, compressors, tanks, piping, reactors, distillation columns, refrigeration systems, and many other kinds of equipment. Materials that cannot be released to the atmosphere are recycled back to the system, or sent to a scrubber or flare system. The discharge from pressure relief equipment is collected in a closed piping system and sent to a flare stack. Harmless gases are discharged at a safe distance from plant operations areas. 

Cyclone Separator with Separate Catch Tank This type of blowdown system, shown in Fig. 26-17 and 26-18, is frequently used in chemical plants where plot pan space is hmited. The cyclone performs the vapor-liquid separation, while the catch tank accumulates the hquid from the cyclone. This arrangement allows location of the cyclone knockout drum close to the reactor so that the length of the relief device discharge hne can be minimized. The cyclone nas internals, vital to its proper operation, which will be discussed in the following sections. 

FIG. 26-22 Multireactor knockout (K-O) drum/catch tank a) plan view of reactors connected to horizontal containment vessel (h) back-to-back bursting disc assembly (c) elevation of self-supporting vessel (d) elevation of horizontal vessel on roof of building (e) elevation of horizontal vessel on side of building. 

General In comparison with design information on blowdown drums and cyclone separators, there is very httle information in the open technical hterature on the design of quench tanks in the Chernies industry. What is available deSs with the design of quench tanks (Sso called suppression pools) for condensation of steam or steam-water mixtures from nuclear reactor safety vSves. Information and criteria from quench tanks in the nuclear industry can be used for the design of quench tanks in the chemicS industry. There have been sev-... 

Vacuum transfer into reactor, drum or feed tank runs dry, resulting in air being pulled into vessel, creating flammable atmosphere. Potential for fire/explosion. 

Reactors Process Towers Marine Veasela Piping Sysloms Heal Exchangers Tanks Unknown Process Drums Miscellaneous Heaiers-Boiiers... 

All vessels need reliefs, including reactors, storage tanks, towers, and drums. 

On the day of the accident, two workers poured four drums of liquid waste into the blending vessel — about half the amount needed to reach the agitator. Then they added solids into the top of the tank about 2 lb each of chlorates, perchlorates, and nitrites. Thirty to 60 seconds after the oxidizers were added and while a fifth drum of solvent was being dumped into the top of the reactor, liquid suddenly erupted out of the vessel manway. The flammable vapor exploded, engulfing one employee, who died, and injuring two others. 

Multireactor knockout drum/catch tank This interesting system is sometimes used as the containment vessel for a series of closely spaced reactors (Speechly et al., Principles of Total Containment System Design, presented at I.Chem.E. North West Branch Meeting, 1979). 

In a first full scale attempt at a new polymerisation process, the thermally unstable initiator was charged and heated to reaction temperature, but there was then an unforeseen delay of an horn before monomer addition was started. The rate of polymerisation effected by the depleted initiator was lower than the addition rate of the monomer, and the concentration of the latter reached a level at which an uncontrollable polymerisation set in which eventually led to pressure-failure of the vessel seals. Precautions to prevent such occurrences are detailed. In another incident, operator error led to catalyst, condensing styrene and acrylonitrile being ducted into an unstirred weighing tank instead of a reactor. When the error was recognised, the reacting mixture was dropped into drums containing inhibitor. One of the sealed drums had insufficient inhibitor to stop the reaction, and it slowly heated and eventually burst [1], The features and use of... 

Rotary Drum Vacuum Filter The underflow from the thickener is the feed to this filter. The filter concentrates the solids (predominately calcium sulfite), which then leave the filter in a cake form and are transferred to a cake repulp tank where they can be reslurried. The liquid generated from the filtering process (filtrate) is collected and pumped to the lime reactor vessel. 

Fig. 1. ASPEN-Plus PFD of carbonic acid pretreatment process as analyzed in this study. Bl, pretreatment reactor (Rstoic) B2, screw mixer B3, blowdown tank and screw conveyor B4, slurrying tank and tank agitator B5, cooler B6, reflux drum and condenser B7, feed pump B8, in-line C02 mixer B9, heater BIO, pneumapress filter Bll, heat exchanger B12, loading pump B13, C02 compressor B14, primary filtrate pump.

MAP and DAP fertilizers are made in a granulation process from ammonia and wet-process phosphoric acid. The acid is partially neutralized in a tank reactor. Ammoniation and granulation are completed in a rotary drum. Drying, cooling and product screening complete the process238. 

Until now, bioreactors of various types have been developed. These include loop-fluidized bed [14], spin filter, continuously stirred turbine, hollow fiber, stirred tank, airlift, rotating drum, and photo bioreactors [1]. Bioreactor modifications include the substitution of a marine impeller in place of a flat-bladed turbine, and the use of a single, large, flat paddle or blade, and a newly designed membrane stirrer for bubble-free aeration [13, 15-18]. Kim et al. [19] developed a hybrid reactor with a cell-lift impeller and a sintered stainless steel sparger for Thalictrum rugosum cell cultures, and cell densities of up to 31 g L1 were obtained by perfusion without any problems with mixing or loss of cell viability the specific berberine productivity was comparable to that in shake flasks. Su and Humphrey [20] conducted a perfusion cultivation in a stirred tank bio-... 

Fig. 2. Emulsion polymerization plant. A, Emulsion feed tank B, polymerization reactor, C, drumming tank F, filter, M, meter, P, pressure gauge T,...

Table I lists the categories of laboratory reactors used for catalyst testing and catalytic process studies, viz., in the order of decreasing size pilot-plant, bench-scale and microflow reactors. Table II compares the feed requirements of some representative examples of these three classes for a typical case of oil hydroprocessing. The large effect of scale is evident whereas the pilot plant consumes monthly amounts of liquid and gas that require supply on a periodic basis by tank car and tube trailers, the microflow needs can be covered by a small drum or can and a few gas bottles. The size of the test reactor does not only have consequences for the logistics of supply, storage and disposal of feeds and products, but can also dictate the scale of preparation of special feedstocks and catalysts.

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