Oxygen removal tower

Figure 2. Oxygen removal tower and outer column for thermal insulation.

Figure 3. Top and bottom component of oxygen removal tower.

When a higher C4 raffinate purity is required it is possible to perform a more efficient removal of oxygenates (mainly DEE) by including an additional distillation tower or an oxygen removal unit (ORU) based on molecular sieves. 

In the feed preparation section, those materials are removed from the reactor feed which would either poison the catalyst or which would give rise to compounds detrimental to product quality. Hydrogen sulfide is removed in the DBA tower, and mercaptans are taken out in the caustic wash. The water wash removes traces of caustic and DBA, both of which are serious catalyst poisons. Also, the water wash is used to control the water content of the reactor feed (which has to be kept at a predetermined level to keep the polymerization catalyst properly hydrated) and remove NH3, which would poison the catalyst. Diolefins and oxygen should also be kept out of poly feed for good operation. 

Chemical and Physical Properties Petroleum fuels contain paraffins, isoparaffins, naphthenes, and aromatics, plus organic sulfur, oxygen, and nitrogen compounds that were not removed by refining. Olefins are absent or negligible except when created by severe refining. Vacuum-tower distillate with a final boiling point equivalent to 730 to 840 K (850 to 1050°F) at atmospheric pressure may contain from 0.1 to... 

The recovery and work-up of these oxygenates is a complex process. The water is first fed to a "primary" distillation tower where the aldehydes, ketones and alcohols are removed overhead. The bottoms retain all the carboxylic acids. These acids can be... 

When a sucrose- or other simple carbohydrate-based solution is mixed with yeast and oxygen in a fermenter, carbon dioxide vapour and alcohol are produced. The carbon dioxide can then be passed through a separator to remove any trace cany-over of foam. Once the foam has been removed the carbon dioxide is compressed. It is then scrubbed with water in a packed tower, removing water-soluble impurities such as alcohol, ketones and other aroma chemicals produced during fermentation. 

A hydrocarbon fuel such as light oil or natural gas can be burned specifically in order to produce carbon dioxide. The flue gas from this process, which contains less than 0.5% oxygen by volume, is cooled and scrubbed to remove any impurities that may be present. The resultant gas is then passed through an absorbent tower, where it comes into contact with a carbon dioxide absorbing solution. The absorbing solution, now rich in carbon dioxide, is pumped to a stripper tower, where the heat from the combustion of the fuel is used to release the... 

Aeration of this water, either as part of a pretreatment process or by recirculation of the water over the cooling tower, will tend to reduce or remove these gases but also will saturate the water with oxygen, which is a primary factor in both corrosion processes and certain inhibitor film-formation mechanisms. 

Hydrogen escaping from electrolyzers in a plant that operates properly contains 3—5 % oxygen and 0.5—2 % chlorine. Sometimes this can be further utilized. In this event the gas is first scrubbed in towers with a caustic soda solution to remove the chlorine, then it passes into the catalytic chambers, where, at 500 °C the oxygen is removed on a catalyst consisting of platinum dispersed on a suitable carrier. The hot purified hydrogen is cooled by spraying with water, then dried and delivered to where required. 

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