Thermal evaporation system

Scrubber brine results from the treatment by the PFS of the process gases coming from the incinerators. Scrubber brine contains water, dissolved salts, suspended solids, and trace amounts of heavy metals. After use, scrubber brine is designated as spent brine and is transferred to storage tanks before off-site shipment to a permitted TSDF. A thermal evaporation system for concentrating the spent brine solution to solid brine salts is used at some sites, while other sites manage this waste as a brine solution. The use of a thermal evaporation brine reduction system may be required by individual site permits. 

Figure 1.5 (a) Typical thermal evaporation system and (b) electron beam evaporation system. Reprinted with permission from Adachi, H., Wasa, K., 2012. Thin films and nanomaterials. 

In the system just considered, neither the humidity nor the temperature of the gas is appreciably changed. If the gas is passed over the liquid at such a rate that the time of contact is sufficient for equilibrium to be established, the gas will become saturated and both phases will be brought to the same temperature. In a thermally insulated system, the total sensible heat falls by an amount equal to the latent heat of the liquid evaporated. As a result of continued passage of the gas, the temperature of the liquid gradually approaches an equilibrium value which is known as the adiabatic saturation temperature. 

In our recent work, we have used Pd deposited on t hkl) in order to characterize thin metal films [Arenz et al., 2002] and to test their catalytic activity (Fig. 8.16). We have employed both methodologies thermal evaporation in UHV and electrochemical deposition. For the Pd/Pt(l 11) system, in situ SXS measurements have been used to show that after the formation of 1 ML of pseudomorphic Pd film, three-dimensional pseudomorphic crystalline islands of pure Pd begin to aggregate. 

Thermodynamically, the concept is similar to thermal wave systems and predicted COP s are similar. A cooling COP of 0.9 (based on heat input to the cycle), is predicted for one design with modest regeneration efficiency, evaporating at 5°C and condensing at 40°C. 

By employing a laser for the photoionization (not to be confused with laser desorption/ ionization, where a laser is irradiating a surface, see Section 2.1.21) both sensitivity and selectivity are considerably enhanced. In 1970 the first mass spectrometric analysis of laser photoionized molecular species, namely H2, was performed [54]. Two years later selective two-step photoionization was used to ionize mbidium [55]. Multiphoton ionization mass spectrometry (MPI-MS) was demonstrated in the late 1970s [56—58]. The combination of tunable lasers and MS into a multidimensional analysis tool proved to be a very useful way to investigate excitation and dissociation processes, as well as to obtain mass spectrometric data [59-62]. Because of the pulsed nature of most MPI sources TOF analyzers are preferred, but in combination with continuous wave lasers quadrupole analyzers have been utilized [63]. MPI is performed on species already in the gas phase. The analyte delivery system depends on the application and can be, for example, a GC interface, thermal evaporation from a surface, secondary neutrals from a particle impact event (see Section 2.1.18), or molecular beams that are introduced through a spray interface. There is a multitude of different source geometries. 

Sodium sulfite scrubbing can be configured as a regenerative process if the regeneration is performed thermally in an evaporator system. Thermal regeneration removes gaseous sulfur dioxide with the sodium bisulfite being converted back to sodium sulfite. The sulfur dioxide is then reduced to elemental sulfur or converted to sulfuric acid. 

Multiple effects evaporation-steam and/or oil, multiple hearth and rotary kiln incineration, and other special thermal oxidation systems. 

Both concentrated and dilute waste were sent to a pair of John Zink thermal oxidizers equipped with adjustable venturi scrubbers for removal of particulates prior to stack discharge. Water process waste originating primarily from fermentation sectors was sent to the Carver-Greenfield evaporation system. The evaporator utilized a multistep oil dehydration process and was equipped with a centrifuge, waste heat boiler, and a venturi scrubber. The Clinton Laboratory reported an overall BOD and COD reduction of 90 and 99%, respectively, depending upon the configuration used. 

Transmission Electron Microscopy (TEM) has been used to characterize aluminum thin films thermally evaporated (vacuum around 10 4 Torr) on Polyethyleneterephtalate (Mylar) and to correlate the crystallographic structure of the system Al/Mylar and the adhesion of the aluminum films. The adhesion of these films has been measured by a Peel test technique. For the polymer, an amorphous layer (t=12 nm) followed by a crystalline film have been observed on a Corona treated film and the opposite configuration has been found on a bi-axially stretched film. Some spherical precipitation ana interdiffusion zones have also be observed in the Mylar for the films which have the lower coefficient of adhesion (100 g/inch). The main conclusion is the augmentation of the adhesion of the aluminum film as the size of the grains decreases and/or as the microroughness of the Al/Mylar interface increases. 

---