Carbon recovery

Equipment. Partial-oxidation gasification section equipment in many plants consists essentially of (/) the gasification reactor (2) the waste-heat exchanger for heat recovery from the hot reactor gas or direct quench system (J) the economizer heat exchanger for further heat recovery (4) the carbon removal system for separating carbon from the reactor product gas and (5) the carbon recovery system for recycle of carbon. 

The water—carbon slurry formed in the quench vessel is separated from the gas stream and flows to the carbon recovery system needed for environmental reasons and for better thermal efficiency. The recovered carbon is recycled to the reactor dispersed in the feedstock. If the fresh feed does not have too high an ash content, 100% of the carbon formed can be recycled to extinction. 

The major process parameters at selected periods in the four experiments are listed in Tables II, IV, VII, and VIII. Carbon recoveries ranged from 63 to 91%. Most of the losses occurred in connection with the recycle compressor system, and they decreased correspondingly the volume of product gas metered. Such losses, however, did not affect significantly the incoming gas to the main reactor or reactor performance. 

Mechanical textile finishing, 24 622 Mechanical tire shredding, 21 470-472 Mechanical vapor recompression (MVR) crystallizers, sodium carbonate recovery via, 22 789 Mechanics, classical and quantum, 16 734-740... 

Monohydrate bauxites, 2 347 Monohydrate crystals, in sodium carbonate recovery, 22 789... 

Monohydrate process, sodium carbonate recovery via, 22 788-789 Monoisopinocampheylborane, 13 635 Monoisopropanolamine (MIPA) physical properties of, 2 123t specifications, 2 132t... 

Multiple chemical sensitivity, 1 817 Multiple consortia technology transfer partnership model, 24 390 Multiple controllers, 20 698 Multiple downcomer plate, 8 764-765 Multiple-effect crystallizers, sodium carbonate recovery via, 22 789 Multiple-effect evaporators, 23 238... 

In the reactor combined UV persulphate oxidation ensures quantitative total organic carbon recovery. The resulting carbon dioxide with entrained water goes through a gas/liquid separator, a water trap and drier before it... 

Studies on the effect of the size of the soil sample taken showed that the total carbon recovery was low when the carbon content of the sample did not exceed lmg or the amount of soil taken exceeded lg. 

Table IV. Organic Carbon Recovery with XAD Columns from Drinking Water Pilot Plant Samples...

Values are the average of the organic carbon recoveries in milligrams per liter obtained at 500, 1000, 1500, and 2000 gal during a typical run. 

The presence of hydrogen, even at low pressure, significantly increases organic carbon recovery compared with hydrogen-free retorting. 

Good organic carbon recovery can be achieved at an elevated hydrogen partial pressure. At 500 psia, slow heating can achieve over 95% recovery. 

The heating rate significantly affects organic carbon recovery. Very rapid heating to 1300°F limits recovery to about 87%. 

Paerl, H.W., 1978. Microbial organic carbon recovery in aquatic ecosystems. Limnol. Oceanogr., 23 927-935. 

In the process, the feedstock, together with the feedstock carbon slurry recovered in the carbon recovery section, is pressurized to a given pressure, mixed with high-pressure steam and then blown into the gas generator through the burner together with oxygen. 

Kawata et al. [ 128] have described the effects of headspace conditions on recoveries of volatile organic compounds from sediments and soils. Hewitt [129] compared three vapour partitioning headspace and three solvent extraction methods for the preparation of soil samples for volatile organic carbon determination in soils. Methanol extraction was the most efficient method of spiked volatile organic carbon recovery, which depended on the soil organic carbon content, the octanol-water partitioning coefficients of analytes and the extraction time. 

Even error-free determination of C02 in the exhaust gas does not necessarily assure correct determination of C02 production (rate) or carbon recovery if the solubility and reactivity of C02 at neutral or alkaline pH is not taken into consideration [311]. C02 dissolves in water to hydrated C02, namely H2O.CQ2,... 

Important is the conclusion that a significant amount of C02 may not be found in the exhaust gas but rather trapped in the culture liquid in the form of bicarbonate or even carbonate (in alkalophilic cultures). For example, Ponti [327] estimated that up to 25% of total carbon mineralized in sewage sludge treatment was captured as bicarbonate and not released via the gas phase. Disregarding this fact must result in systematically erroneous determinations of respiratory quotient (RQ), carbon dioxide production rate (CPR) and carbon recovery. However, taking all these factors into account allows the determination of the RQ-value, even in mammalian cell cultures, with reasonable accuracy even though bicarbonate and low gas turnover rates hamper the measurements [38]. 

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