Costs removal systems

The choice of a specific CO2 removal system depends on the overall ammonia plant design and process integration. Important considerations include CO2 sHp required, CO2 partial pressure in the synthesis gas, presence or lack of sulfur, process energy demands, investment cost, availabiUty of solvent, and CO2 recovery requirements. Carbon dioxide is normally recovered for use in the manufacture of urea, in the carbonated beverage industry, or for enhanced oil recovery by miscible flooding. 

Based on dryer cost alone, indirect-heat dryers are more expensive to build and install than direct-heat dryers designed for the same duty. As environmental concerns and resulting restrictions on process emissions increase, however, indirect-heat dryers are more attractive because they employ purge gas only to remove vapor and not to transport heat as well. Dust and vapor recovery systems for indirect-heat dryers are smaller and less cosdy to supply heat for drying, gas throughput in direct-heat dryers is 3—10 kg/kg of water evaporated indirect-heat dryers require only 1—1.5 kg/kg of vapor removed. System costs vary directly with size, so whereas more money may be spent for the dryer, much more is saved in recovery costs. Wet scmbbers ate employed for dust recovery on indirect-heat dryers because dryer exit gas usually is close to saturation. Where dry systems are employed, all external surfaces must be insulated and traced to prevent vapor condensation inside. 

A. Hausberger I think a sulfur-tolerant catalyst would definitely be an advantage in that the requirement for critical control of the sulfur removal system would be eliminated. If you can allow some sulfur to pass on through the methanator into the product gas, the amount of reagent or regeneration cost of the sulfur removal system would be reduced. As to what level of sulfur could be tolerated, that is a hard question to answer since I don t think that there is a sulfur-tolerant catalyst. 

Based on the result of bench- and pilot-scale testing, cost estimates were determined for Krudico, Inc., ion exchange system treatment of groundwater contaminated with nitrate and perchlorate at the U.S. Department of Energy s (DOE s) Lawrence Livermore National Laboratory. Costs were estimated to cover three options nitrate removal only, perchlorate removal only, and removal of both nitrate and perchlorate. The proposed treatment system would treat approximately 1,839,600 gal of contaminated groundwater at a treatment rate of 3.5 gallons per minute (gpm). Nitrate removal was estimated to cost 0.15/gal, perchlorate removal was estimated at 0.02/gal, and a combined removal system was estimated to cost 0.16/gal (D20493D, p. 12). 

The primary application of the BERT technology will likely be to complement active soil vapor extraction efforts by removing residual contaminants after active methods become insufficient. It could also be used on the edge of unsaturated zone contaminant plumes where concentrations of volatile contaminants are low or for enhancement of bioremediation activities. The primary advantages of the technology application are low capital costs and minimal operating costs. The system is well suited for applications in low-risk contaminant settings, where rapid response and remediation are not necessary. Suitable applications include volatile contaminants at relatively shallow depths (less than 20 ft) in the vadose zone, such as ... 

TABLE 1 Cost Estimate for Treatment of Supernatant at the Oak Ridge Reservation Using the Cesium Removal System... 

The selection requirements for each of the components of the SCWO system for treating a variety of waste types comes from environmental regulations, waste characteristics, and cost and safety criteria. Similar to the bench-scale experimental design, the major components to be included in the SCWO design involve three main subsystems (influent introduction, reactors, and effluent removal systems). Other auxiliary systems such as heat exchangers and effluent exhaust systems must also be designed. In addition, for scale-up operations, the waste pretreatment and handling systems have to be considered. Fig. 10 shows a schematic of a complete system. 

The secondary reformer vessel is a refractory-lined vessel that has an oxygen burner in its top neck and a fixed catalyst bed. Installation of a secondary reformer usually requires significant changes to the CO2 removal system Hydrogen purity can be increased up to 98%. The economics generally depend on a reliable source of low-cost oxygen172. 

Figure 2, RC/Bahco SOj removal system estimated installed cost vs. capacity (carbon steel modules less turnkey)...

Similarly to the zirconocene/MAO catalysts, the activity of the Idemitsu catalyst systems is poor when the whole catalyst system (catalyst-i-co-catalyst) is taken into account. In the very best example (in terms of catalyst activity and polymer yield) nickel bis (acetylacetonate) was used in combination with MAO (molar ratio 1 200) to homopolymerize norbornene in toluene at 50 °C for 4 h affording a 70% conversion into high molecular weight (M 2.2x10 ), toluene-soluble poly-(norbornene). The ratio of norbornene to nickel was 20000 1 and the ratio of norbornene to aluminum was only 100 1. Thus, while the yield of polymer is high based on the nickel catalyst (25 700 g per g nickel), the yield based on aluminum is very poor (260 g per g aluminum or about 120 g per g MAO). It can readily be estimated that the cost of the MAO activator alone would add significantly to the cost of the polymer, as well as requiring costly removal of catalyst residues from the polymer. 

When integrated with a steam reformer, the Hyco process results in a CO product cost savings of up to 15% over conventional systems of C02 solvent removal plus cryogenics. This process eliminates the need for a separate C02 removal system. The purity of CO is greater than 99.5% and the high purity CO can be produced in a single stage. The product CO is suitable for use in the production of isocyanates, acetic acid, oxo alcohols, and specialty chemicals that are covered in this book. 

Ostertag s committee painted the picture of water pollution in shades quite different from those Dickey had used. Industrial wastes received equal billing with sewage. While the committee repeated the usual platitudes about industry s desire to reduce pollution, the facts it compiled made clear that real progress was slow. Numerous sites of industrial pollution were mapped, with chemical plants in Buffalo seen as a particular problem. Aside from the Long Island chromium removal systems, only three major industrial treatment facilities were built anywhere in the state in 1948. The total construction cost of needed industrial waste treatment... 

Since the MgO spray dryer FGD process collects particulate matter as an inherent part of the FGD system, it can be evaluated either as a combined particulate-S02 removal system or, with the inclusion of an ESP credit, as an FGD-only process. In this study the spray dryer MgO process evaluation is based on the combined particulate-502 removal system. The primary reasons are that the combined system is easier to explain and that similar evaluations for the limestone scrubbing/ESP and conventional MgO/ESP systems are available from previous studies (2, jj). The conventional MgO/ESP process cost information from the previous study was updated using area scale factors, relative product and gas rates, etc., to put the results on a consistant basis with the current evaluation of the spray dryer MgO process. 

Comparative cost estimates are presented in Table 4 for ethylene oxide processes. The higher cost of ethylene feedstock for the air-based process is a reflection of lower overall yield. More ethylene is required to compensate for the quantity that is oxidized to carbon oxides. This cost advantage for the oxygen-based process is partially offset by the cost of the oxygen and the higher cost for methane ballast gas and other chemicals for the carbon dioxide removal system. 

The number of streams feeding the plant, the number of contaminated streams, the mercury concentration and the type of mercury removal system considered aU have a potential impact on the cost of the removal system. For overall economic assessment, one should consider the in-plant impact and the cost of removal systems for regeneration/waste effluent systems as well as down-stream client impacts. One should also consider other contaminants which are present in the natural gas condensate i.e. mainly arsenic but also sometimes phosphorus, lead or sihcon. For these contaminants, there is no removal process which is industrially apphed on the steam-cracker effluents. 

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