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Caustic waste

A large use of molecular sieves ia the natural gas industry is LPG sweetening, in which H2S and other sulfur compounds are removed. Sweetening and dehydration are combined in one unit and the problem associated with the disposal of caustic wastes from Hquid treating systems is eliminated. The regeneration medium is typically natural gas. Commercial plants are processing from as Htde as ca 30 m /d (200 bbl/d) to over 8000 m /d (50,000 bbl/d). [Pg.457]

The process starting from lignin has faced serious problems, such as reduced availabiUty and environmental impact. The availabiUty is reduced because the new process for making paper paste yields less Hquor. As a result, it is likely that the larger companies will not reinvest in new factories to process Hquors to meet demand. The process s environmental impact is also problematic because over 160 t of caustic waste are produced for every ton of vanillin manufactured. [Pg.397]

Several units are used for sulfite-paper-mill waste-liquor disposal. At least six units are used for oil-refinery wastes, whicdi sometimes include a mixture of liquid sludges, emulsions, and caustic waste... [Pg.1574]

Originally cresylic acid was obtained from caustic waste streams that resulted from treating light distillates with caustic solutions to reduce H2S and mercaptans. Currently, most of these streams are hydrodesulfurized, and the product streams practically do not contain phenolic compounds. [Pg.131]

Where low to moderate flow rates are encountered, it is likely that EDI is less expensive when both capital and maintenance costs are considered. For high flow rate systems, there is little to choose between the three technologies, although the EDI does have the advantage of not producing acid or caustic waste streams. [Pg.375]

Velsicol Chemical Corporation maintained two injection wells at its plant near Marshall, Illinois, to dispose of caustic wastes from pesticide production as well as contaminated surface runoff. In September 1965, the company began to inject the wastes into Devonian dolomites of the Grand Tower Formation at a depth of about 2600 feet. The wells accepted about 6 million gallons of waste monthly. [Pg.428]

Hydrofluoric acid (HF) alkylation units have small acid remn units to purify the acid for reuse. HF units do not have a spent acid or spent caustic waste stream. Any leaks or spills that... [Pg.246]

Delmau proposed the combined extraction of cesium and strontium from caustic wastes by adding a crown ether and a carboxylic acid to the CSSX solvent.126 The classical DtBuC18C6 and one carboxylic acid were combined with the components of the CSSX solvent optimized for the extraction of cesium, allowing for the simultaneous extraction of cesium and strontium from alkaline nitrate media simulating alkaline high-level wastes present at the SRS. The promising results of these batch tests showed that the system could reasonably be tested on actual waste. [Pg.244]

The pH values at the respective equivalence points (around 4.5 and 10.3) for titrations of alkalinity and acidity represent approximate thresholds beyond which most life processes in natural waters are seriously impaired. Thus alkalinity and acidity are convenient measures for estimating the maximum capacity of a natural water to neutralize acidic and caustic wastes without permitting extreme disturbance of biological activities in the water. [Pg.167]

The second equation relates Y. and via the fraction recovered in the caustic waste... [Pg.606]

Mound Facility Caustic Waste. About 6000 l of so-called caustic waste containing 0.5 to as much as 8 mg Pu/ are generated yearly at the Mound Facility. The bulk (90 vol ) of this particular waste stream consists of a k wt NaOH solution used as a scrubber in the corrosive off gas system. The remainder originates as filtrates from NH OH precipitation of Pu(0H)i ... [Pg.27]

Results from the pilot plant studies were used to design a conceptual plant-scale system for treating the caustic waste. [Pg.27]

Figure 3. Pilot plant test of combined filtration-bone char decontamination of mound facility caustic waste fH) after filters, (A) after first bone char column, (O) after second bone char column, (%) after fourth bone char column. Conditions pH = 8 flow = 20 ml/min total bed height, 2.0 m of 275-fi bone char diameter of bed, 5.1 cm intial [Pu], 8 mg/L (3. X 1011 d/m/ml). Figure 3. Pilot plant test of combined filtration-bone char decontamination of mound facility caustic waste fH) after filters, (A) after first bone char column, (O) after second bone char column, (%) after fourth bone char column. Conditions pH = 8 flow = 20 ml/min total bed height, 2.0 m of 275-fi bone char diameter of bed, 5.1 cm intial [Pu], 8 mg/L (3. X 1011 d/m/ml).
The oxidation mixture with about 5% cyclohexanone, cyclohexanol, and CHHP that is discharged from the last oxidation reactor is fed as such to the neutralization and decomposition section. In addition, an aqueous caustic solution and optionally a catalyst are fed to this section. In the resulting biphasic system, the CHHP is almost completely decomposed and the acids are neutralized. Subsequently, the biphasic system is separated into an aqueous slightly caustic waste stream and a cyclohexanol and cyclohexanone containing cyclohexane stream. The molar ratio between cyclohexanone and cyclohexanol, also called KA ratio, ranges from 0.3 to 0.8. [Pg.38]


See other pages where Caustic waste is mentioned: [Pg.163]    [Pg.428]    [Pg.429]    [Pg.20]    [Pg.604]    [Pg.445]    [Pg.163]    [Pg.1076]    [Pg.174]    [Pg.27]    [Pg.27]    [Pg.28]    [Pg.1888]    [Pg.63]    [Pg.35]    [Pg.723]    [Pg.1878]    [Pg.310]    [Pg.39]    [Pg.40]    [Pg.98]    [Pg.1449]   
See also in sourсe #XX -- [ Pg.433 ]




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