Brine storage tanks

Figure 24. Schematic diagram of a brine circulation system in the mercury cell process a) Electrolysis cell b) Anolyte tank c) Vacuum column dechlorinator d) Cooler e) Demister f) Vacuum pump g) Seal tank h) Final dechlorination i) Saturator k) Sodium carbonate tank I) Barium chloride tank m) Brine reactor n) Brine filter o) Slurry agitation tank p) Rotary vacuum filter q) Vacuum pump r) Brine storage tank s) Brine supply tank...

Most commonly, diaphragm cells are supplied with well brine on a once-through basis. The treated well brine flows to the treated brine storage tanks, which usually have 12-h capacity. From there the brine is fed to the cell room. The flow to each individual electrolyzer is controlled by a rotameter. If the flow of brine to the cells is suddenly disrupted by failure of the brine feed pump, the rectifiers automatically shut down since an inadequate supply of brine to the cells is potentially unsafe. The specifications for brine for diaphragm cells are given in Table 13. 

The preferred brine circuit is that shown in Figure 12.5, and having the feed and expansion tank out of the circuit, which is otherwise closed. This avoids entrainment of air and too much surface exposure. The same arrangement can be used with the divided storage tank shown in Figure 12.6, except that the tank will be enclosed, with a separate feed and expansion tank. 

The annual cycle energy system (ACES) has two basic components a very large insulated storage tank of water and a heating-only heat pump. The tank contains coils of pipe filled with brine (salt water) warmed by the water in the tank. The brine circulates through a heat exchanger and transfers its heat to the heat pump refrigerant. 

Scrubber brine results from the treatment by the PFS of the process gases coming from the incinerators. Scrubber brine contains water, dissolved salts, suspended solids, and trace amounts of heavy metals. After use, scrubber brine is designated as spent brine and is transferred to storage tanks before off-site shipment to a permitted TSDF. A thermal evaporation system for concentrating the spent brine solution to solid brine salts is used at some sites, while other sites manage this waste as a brine solution. The use of a thermal evaporation brine reduction system may be required by individual site permits. 

The second typical technology applied for d. of water is -> electrodialysis. After appropriate pretreatment (as above), the feed solution is pumped through the unit of one or more stacks in series or parallel. The concentrated and depleted process streams leaving the last stack are recycled, or finally collected in storage tanks. The plants operate unidirectionally, as explained, or in reverse polarity mode, i.e., the current polarity is changed at specific time intervals (minutes to hours), and the hydraulic flow streams are reversed simultaneously, thus preventing the precipitation in the brine cells. 

The fluid discharged from the SCWO reactor passes through a cooler and enters a phase-separation vessel. Gases and liquids then flow to separate pressure-reduction stations before entering a low-pressure phase-separation vessel. Noncondensable gases, mostly carbon dioxide, are monitored and filtered before release to the environment via the plant HVAC system. Liquids are monitored and transferred to the brine recovery area, which is identical to the one used in the baseline incineration system. If fluid does uot meet release specifications, it is returned to a storage tank for off-specification product and reprocessed in the SCWO reactors. 

Solvent contaminated] carryover from upstream equipment example oil from compressor brines, corrosion inhibitors, sand, [corrosion products, see Section 1.3] /oxygen leaks into storage tank/inadequate corrosion control, example low pH causing corrosion/degradation via overheating, ex hot spots in reboiler tubes or fire tubes/ineffective filters/ineffective cleaning before startup/for amine absorbers corrosion products/FeS/chemicals used to treat well. 

Storage tanks for purified brine This is required for continuous process Uniform production rate is affected if storage of brine is not sufficient Capacity shall be enough for 16-24 h requirement... 

For added security, vents from the tails tower and the product storage tank can be scrubbed with a caustic liquor. The acid solution itself will contain a small amount of dissolved chlorine. In most plant applications, as for example in the acidification of depleted brine, this is not a problem. Other uses, such as the regeneration of the brine softening resin in a membrane-cell plant, may require that this chlorine be removed. Adsorption on activated carbon is probably the simplest technique for this small-scale process, which is similar to that described in Section 7.5.9.3B. 

Individual sections of the brine plant may be interconnected by level, pressure, or flow controllers. Some unit operations function better if they are fed by flow or pressure control systems. Whenever this is the case, a storage tank with a floating level can... 

Brine from the top of the clarifier overflows by gravity to the clarifier pump tank. A turbidity meter in this line can monitor the solids content and provide an alarm in case of an upset in the clarifier operation. Again, operation and control are similar to those discussed in connection with brine saturation. The top of the tank should be at least as high as the top of the clarifier overflow system. This provides more brine storage capacity as well as time to correct a pump failure or other simple operating problems. The normal level in the pump tank is about 50%. Level control options are as in Fig. 11.3 ... 

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