Steam, evaporation

The sprayed electrode boiler boiler is provided with a pump that draws BW from close to the bottom of the pressure vessel and circulates it back to the top of the vessel into an injection cylinder. From there the water is sprayed through multiple jets directly onto the electrodes, a current path is established, and steam is produced. However, the water flow is considerably greater than the steam evaporation rate, and the excess water is recirculated once more around the boiler... 

Carver-Greenfield multistage, oil dehydration, steam evaporator system (fermentation waste) ... 

The plant consists of a pre-reforming step which converts C2+ into methane, which also reduces the coking risk downstream (Figure 4.50). The actual reforming step, the water gas shift reaction, follows and also a step for the selective oxidation of carbon monoxide before the hydrogen-rich gas enters the fuel cell. A steam evaporator is also included in the set-up. 

If water is the solvent, it is generally removed by evaporation rather than by distillation unless products are present which are volatile with steam. Evaporation should be done with constant stirring. The process can be accelerated still more by removing the steam rapidly by means... 

The evaporation process can be divided into the broad categories of steam evaporation and solar evaporation. 

Steam Evaporation In this process, steam is used to raise the temperature of solution to its boiling point. The process is carried out either at a pressure less than atmospheric (vacuum evaporation) or at atmospheric pressure (atmospheric evaporation). 

It is generally stated that one pound of steam evaporates I 8 lbs. of water in a double effect, 27 lbs. in a triple effect, and 3 "5 lbs. in a quadruple effect, but these figures will necessarily vary with the conditions of the evaporation, besides which the steam used in working the vacuum and other pumps must be taken into account. 

In passing through the carbon bed, the steam evaporates the adsorbed solvent and conveys it to the exit where the steam is condensed and the solvent is recovered in a liquid state. A solvent that is not appreciably soluble in water can be separated from the water layer by continuous decantation. Water-soluble solvents are separated by fractional distillation. 

STATE - Refers to the form of a fluid, either liquid, gas or solid. Liquids used in environmental systems are water, thermal fluids such as ethylene glycol solutions, and refrigerants in the liquid state. Gases are steam, evaporated refrigerants and the air-water vapor mixture found in the atmosphere. Some substances, including commonly used refrigerants, may exist in any of three states. A simple example is water, which may be solid (ice), liquid (water), or gas (steam or water vapor). 

Be careful when doing this. Make sure to let the steam evaporate — don t let it... 

At Helsinki University of Technology, successful demonstration of fluidized bed drying of peat has been reported at the pilot plant level (100 kg/ h of water evaporated). A tubular heat exchanger immersed in the bed provides indirect heat for drying. It uses condensing steam at 0.8 MPa. Steam evaporated from peat is used as the fluidizing medium. Wet peat is fed into the lower zone of the fluid bed while dry peat is withdrawn from the upper zone by a screw conveyor. The miffed peat is about 1 mm in average size. The... 

The secondary circuit is composed of two loops, each one includes one secondary pump, one steam evaporator, one steam-water separator, one superheater, one expansion tank, valves and draining tank and emergency draining tanks. The steam generators will produce 96.2t/h dry steam with die temperature 480 C and the pressure 14 MPa for a 25MWe turbine generator. The heat in the condenser will dissipate to the air by a cooling tower. 

The pressurizing system is intended for creating and maintaining the primary circuit preset pressure whatever the variation of the coolant volume during reactor operation. The pressurizer is formed by a steam-gas plenum under the reactor cover. For initial filling of the pressurizer nitrogen is used. The additional pressurization is done by steam evaporation from the primary coolant surface. The partial pressure of nitrogen above the coolant level is 3.9 MPa. 

Monthly, the low-water cutoff should be tested under actual operating conditions. With the burner operating and the boiler steaming at the proper water level, close all the valves in the feedwater and condensate return lines for the duration of the test and shut off the feedwater pump, if required, so that the boiler will not receive any placement water. Then carefully observe the waterline to determine where the cutoff switch stops the burner in relation to the lowest permissible waterline established by the boiler manufacturers. The boiler water level should never be allowed to drop below the lowest visible part of the water-gauge glass. If the cutoff does not function during this test, immediately stop the operation of the burner. Then determine the cause of the failure and remedy it. The slow steaming evaporation test should then be repeated to verify that the control does function correctly. 

The three effects of a triple-effect evaporator are operated at 12, 7, and 2 psia, respectively. How man) pounds of water will 1 lb of 20 psia saturated steam evaporate, excluding losses How many pounds of solution can be concentrated from 35 to 70 weight percent solids from 1 lb of steam ... 

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