A few from a search in Applied Science and Technology (FirstSearch):
SEARCH STRING: su:solvent recovery
AUTHOR: Perlmutter, Barry A.
TITLE: New techniques for solvent recovery and elimination of
wastewater emissions during vaccum process operations.
SOURCE: Environmental Progress v. 16 (Summer '97) p. 132-6 bibl diags.
STANDARD NO: 0278-4491
DATE: 1997
PLACE: United States
RECORD TYPE: art
CONTENTS: feature article
ABSTRACT: The pharmaceutical and chemical process industries are
concerned with controlling volatile organic compound (VOC)
emissions for several reasons: to meet environmental
regulations, for increased worker safety, and to minimize
product losses. Various methods can be used including flaring
and carbon adsorption. These techniques are end-of-the-pipe
solutions and are not integral with the process operation
itself. An improved technique for the recovery of solvents
during reaction, distillation, evaporation, drying,
filtration, mixing, and other vacuum operations is the APOVAC
vacuum/gas compressor system. The skid-mounted, engineered
package is based upon a single stage liquid ring vacuum pump.
The system allows for the recover and reuse of clean solvent
with minimum air emissions and zero liquid emissions. VOC and
biological oxygen demand (BOD) regulations are met by this
technology. The paper reviews the technical details of the
system and presents test results and on-site operational data.
Specific case histories involving methylene chloride recovery
and acid/toxic gas neutralizations are also included. In the
chemical processing industry (CPI) the generation of vacuum is
a necessity. Many chemical processes take place more easily,
more quickly and more efficiently under vacuum than under
atmospheric pressure, thus allowing better product quality at
lower production cost. If it is a "wet" process involving the
use of solvents then solvent recover becomes an important
consideration because of cost savings associated with its
recovery as well as environmental benefits. These objectives
have stimulated the development of the APOVAC system concept
which is based on the principle of closed loops or circuits.
Since its development, the APOVAC system has enhanced todays
chemical process technology through solvent recovery and
recycling, elimination of wastewater effluent, and reduction
of gas emissions thus contributing to a technically efficient
and environmentally acceptable operation. Reprinted by
permission of AIChE. Copyright 1997, AIChE.
SUBJECT: Solvents reclamation.
Vacuum pumps.
Volatile organic compounds.
SEARCH STRING: sh=solvents reclamation
AUTHOR: Kilduff, James E.; King, C. Judson.
TITLE: Effect of carbon adsorbent surface properties on the uptake
and solvent regeneration of phenol.
SOURCE: Industrial & Engineering Chemistry Research v. 36 (May '97) p.
1603-13 bibl.
STANDARD NO: 0888-5885
DATE: 1997
PLACE: United States
RECORD TYPE: art
CONTENTS: feature article
ABSTRACT: An investigation was made of the effects of surface properties
on the uptake of phenol by carbonaceous adsorbents and on
subsequent regeneration by acetone leaching. As-received
carbons derived from different source materials were evaluated
at pH values 2 and 9, and the surface properties of selected
adsorbents were varied by surface oxidation with concentrated
HNO3 and/or heat treatment under nitrogen. Carbons derived
from different source materials exhibited similar total uptake
and reversible (acetone extractable) uptake at pH 2 but
exhibited a wide range of reversibility at pH 9, conditions
that promote oxidative coupling reactions. Surface acidity
was investigated as a factor contributing to the reversibility
of as-received carbons, and surface oxidation was evaluated as
a means of improving regenerability. Oxidation of coal- and
wood-based adsorbents with concentrated HNO3 increased surface
acidity as measured by Boehm titration techniques and reduced
the uptake of phenol but increased the reversible uptake.
Reversibility was found to correlate with total acidity,
reaching an upper plateau at a surface acidity of about
1mequiv/m2. Uptake of water vapor by surface-treated carbons
correlated with surface acidity, suggesting that selectivity
for water may contribute to the suppression of oxidative
coupling reactions. Copyright 1997, American Chemical
Society.
SUBJECT: Phenol.
Solvents reclamation.
Carbon, Activated - Testing.
AUTHOR: Liu, Yujun.; Ritter, James A.
TITLE: Evaluation of model approximations in simulating pressure
swing adsorption-solvent vapor recovery.
SOURCE: Industrial & Engineering Chemistry Research v. 36 (May '97) p.
1767-78 bibl.
STANDARD NO: 0888-5885
DATE: 1997
PLACE: United States
RECORD TYPE: art
CONTENTS: feature article
ABSTRACT: Sixteen different mathematical models, based on all
combinations of four major assumptions (i.e., frozen solid
phase during pressurization/blowdown, isothermal, equilibrium,
and constant gas phase velocity during constant pressure
steps), were evaluated in simulating a pressure swing
adsorption-solvent vapor recovery process, which was
representative of any Langmuirian system utilizing a Skarstrom-
type cycle. The evaluation was based on the bed dynamics and
process performance predicted by each model, and obtained from
a 24 full factorial design. Overwhelmingly, the results
showed that the predictions of the process dynamics and
performance from the 16 different models varied widely, and
depended on which combination of assumptions was applied.
Qualitative trends, based on the factorial analysis, indicated
that both the constant velocity and frozen assumptions caused
an overprediction in the solvent vapor enrichment and the bed
capacity factor; and significant interaction effects existed
between these two assumptions. Also, all of the models that
assumed local equilibrium underestimated both the solvent
vapor enrichment and the bed capacity factor, whereas all of
the isothermal models overestimated the solvent vapor
enrichment but underestimated the bed capacity factor.
Copyright 1997, American Chemical Society.
SUBJECT: Pressure swing adsorption process - Computer simulation.
Vapor recovery systems.
Solvents reclamation.
AUTHOR: Price, J.; Burns, D.
TITLE: Clean amine solvents economically and online.
SOURCE: Hydrocarbon Processing (International edition) v. 74 (Aug.
'95) p. 140-1 il.
STANDARD NO: 0018-8190
DATE: 1995
PLACE: United States
RECORD TYPE: art
CONTENTS: feature article
ABSTRACT: A refinery in Arkansas City, Kansas, uses electrodialysis
technology for contaminant removal. Using electrodialysis
technology to clean amine solvents is economically competitive
with conventional change-out or "bleed and feed" methods
because a unit shutdown is not needed to perform the process.
At the refinery, a standard amine-based chemical absorbent
system is used to remove undesirable components such as
hydrogen sulfide and carbon dioxide. The system uses N-
methyldiethanolamine-based product to selectively absorb
contaminants. Amine is regenerated by removing contaminants
with steam stripping, and lean amine is subsequently
recirculated to the absorbers.
SUBJECT: Amines.
Solvents reclamation.
Dialysis.
AUTHOR: Sakuth, M.; Meyer, J.; Gmehling, J.
TITLE: Vapor phase adsorption equilibria of toluene + 1-propanol
mixtures on Y-zeolites with different silicon to aluminum
ratios.
SOURCE: Journal of Chemical and Engineering Data v. 40 (July/Aug. '95)
p. 895-9 bibl diags.
STANDARD NO: 0021-9568
DATE: 1995
PLACE: United States
RECORD TYPE: art
CONTENTS: feature article
ABSTRACT: Zeolites with various silicon to aluminum ratios usually
exhibit polar and nonpolar adsorption behavior depending on
the degree of dealumination. The objective of the present
study was to show the influence of the surface polarity on the
adsorbate phase composition containing a polar and a nonpolar
component: toluene and 1-propanol, respectively. Such
systematic investigations should help to understand the
significance of some adsorbent parameters, such as the surface
heterogeneity. This basic knowledge is important for the
development of improved models for the prediction of
multicomponent adsorption equilibria. Copyright 1995,
American Chemical Society.
SUBJECT: Solvents reclamation.
Polar solvents.
Zeolite Y.
AUTHOR: Layman, Patricia.
TITLE: Dow promotes efficient use of solvents. (Safechem)
SOURCE: Chemical & Engineering News v. 73 (Mar. 20 '95) p. 16
STANDARD NO: 0009-2347
DATE: 1995
PLACE: United States
RECORD TYPE: art
CONTENTS: feature article
ABSTRACT: Dow Chemical has developed a "specialty chemicals" approach to
marketing chlorinated solvents in response to a changing
regulatory environment for these products in the European
market. Working with equipment suppliers and customers of
chlorinated solvents, Dow Chemical has formed a joint venture,
Safechem, with a subsidiary of the German oil conglomerate
Veba to recover and recycle the solvents.
SUBJECT: Solvents reclamation.
Chlorocarbons.
Joint ventures.
AUTHOR: Ruhl, John.
TITLE: Carbon adsorption: a time-tested method of solvent recovery.
SOURCE: Modern Paint and Coatings v. 84 (July '94) p. 40-2 flow sheet
diags.
STANDARD NO: 0098-7786
DATE: 1994
PLACE: United States
RECORD TYPE: art
CONTENTS: feature article
ABSTRACT: The recovery of solvent vapors from industrial processes using
carbon adsorption is described. A recovery plant is composed
of at least 2 vessels or tanks containing activated carbon.
Process air containing the solvent is passed through one tank
where the solvent adsorbs onto the carbon and the cleaned
process air escapes to the atmosphere. In the second part of
the process, live steam is passed through the bed in the
opposite direction to the original process flow. The steam
heats up the carbon, thereby releasing the solvent. The steam
is then condensed in a shell and tube heat exchanger using
cooling water. The condensed water/solvent mixture is allowed
to separate by gravity in a decanter in the case of water
insoluble solvents such as toluene. This basic process has a
major application in the coatings industry, where many
coatings lines are connected to solvent recovery.
SUBJECT: Solvents reclamation.
Thermal swing adsorption process.
Adsorption apparatus - Design.