Steam saturated process

Incorporation of a feed gas saturator cod in the convection section of the primary reformer allows for 100% vaporization of the process condensate. The steam is used as process steam in the reformer. 

For most chemical plants, process steam is used at pressures of 1.825 MN/m" (250 psig), saturated or lower. When combined heat and power generation is economically justified, the steam may be generated at about 5.96 MN/m" (850 psig) appropriately superheated and used to drive back-pressure steam turbines passing out process steam at the required pressure level. 

Figure 5-5. The ICI low-pressure process for producing methanol " (1) desulfurization, (2) saturator (for producing process steam), (3) synthesis loop circulator, (4) reactor, (5) heat exchanger and separator, (6) column for light ends recovery, (7) column for water removal.

A paraffin hydrocarbon of molecular mass 114 kg/kmol at 373 K, is to be separated from a mixture with a non-volatile organic compound of molecular mass 135 kg/kmol by stripping with steam. The liquor contains 8 per cent of the paraffin by mass and this is to be reduced to 0.08 per cent using an upward flow of steam saturated at 373 K. If three times the minimum amount of steam is used, how many theoretical stages will be required The vapour pressure of the paraffin at 373 K is 53 kN/m2 and the process takes place at atmospheric pressure. It may be assumed that the system obeys Raoult s law. 

The flow diagram is for the production of 5000 kW gross and 20,000 lb/hr of saturated process steam at 20 psia. The feed and hot well pumps make the net power production 4700 kW. Conditions at... 

A. The validation of sterilization processes using saturated steam as the sterilant. 

The desulfurized gas is then countercurrently contacted against hot water which heats the feedstock and saturates it with water vapor providing 49% of the process steam requirements. (Over 60% for a plant with CO addition). 

Feedstock Saturator. The feedstock saturator provides over 49% of the process steam (60% with C02 addition). 

In the present instance, a continuous process takes saturated steam into some sort of apparatus, and heat is made continuously available at a temperature level of 200°C. Since cooling water is available at 0°C, maximum use can be made of the steam by cooling it to this temperature. We therefore assume that the steam is... 

Description The gas feedstock is compressed (if required), desulfurized (1) and sent to a saturator (2) where process steam is generated. All process condensate is reused in the saturator resulting in a lower water requirement. The mixture of natural gas and steam is preheated and sent to the primary reformer (3). Exit gas from the primary reformer goes directly to an oxygen-blown secondary reformer (4). The oxygen amount and the balance between primary and secondary reformer are adjusted so that an almost stoichiometric synthesis gas with a low inert content is obtained. The primary reformer is relatively small and the reforming section operates at about 35 kg/cm2g. 

Description Gas feedstock is compressed (if required), desulfurized (1) and sent to the optional saturator (2) where some process steam is generated. The saturator is used where maximum water recovery is important. Further process steam is added, and the mixture is preheated and sent to the pre-reformer (3), using the Catalytic-Rich-Gas process. Steam raised in the methanol converter is added, along with available C02, and the partially reformed mixture is preheated and sent to the reformer (4). High-grade heat in the reformed gas is recovered as high-pressure steam (5), boiler feedwater preheat, and for reboil heat in the distillation system (6). The high-pressure steam is used to drive the main compressors in the plant. 

Description The gas feedstock is compressed (if required), desulfurized (1) and sent to a saturator (2) where process steam is generated. All process condensate is reused in the saturator resulting in a lower water requirement. The mixture of natural gas and steam... 

Steam system and waste heat recovery were improved by the following measures increased pressure and superheating temperature of high-pressure steam providing a part of the process steam by natural gas feed saturation [651], [1033], [1040]-[1042] inclusion of a steam superheater downstream of the secondary reformer [985], [1043]. 

Feed gas is purified in a hydrodesulfurization unit operating at lower than usual temperatures and passes through a saturator to supply a part of the process steam, while the balance is injected as steam. Heated in an inlet-outlet exchanger to 425 °C... 

Reaction heat from the loop is recovered as steam and saturator water, and is used directly as process steam for the reformer. A purge is taken from the synthesis loop to remove inerts (nitrogen, methane), as well as surplus hydrogen associated with non-stoichiometric operation. Also, the purge is used as fuel for the reformer. 

Problem 4.20 A Carnot cycle operates in a closed system using steam saturated liquid at 20 bar (state A) is heated isothermally until it becomes saturated vapor (state B), expanded by reversible adiabatic process to 10 bar (state C), partially condensed to state D, and finally compressed by reversible adiabatic process to initial state A. 

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