Solvent management

As to the particular way in which solvent manages to creep through the membrane, to the exclusion of solute, nothing definite can be said. We might assume that the action of the membrane is of the character of a sieve, the smaller solvent molecules getting through its pores whilst the larger... 

There are typically six components in an HPLC system (1) solvent reservoirs (2) a pumping or solvent management system (3) an injector, which can be either manual or automated (4) a column (5) a detector (6) a data recorder, which can be an integrator or a computer system. 

As the problem of management of solvent waste is a common problem within the automotive sector in Egypt, this case might be very interesting to other automotive companies to join a regional project on solvent management. 

The checklist is divided into three areas 1) Material Storage and Handling, 2) Production Processes and 3) Treatment Alternatives. Material degradation, samples, spills, storage, and inspections are addressed in the first section. Production processes include source reduction for process bath solutions and rinse systems, resource recovery and recycling, and solvent management. Treatment Alternatives focuses on process water pretreatment, modification of conventional wastewater treatment, and alternative waste treatment methods. Each of these subsections follow the question and answer format. 

Drain, F., Moulin, J.P., Gillet, B. 2000. Advanced solvent management in the La Hague reprocessing plants. AIChE Spring Meeting, March 5-9, Atlanta, GA. 

Nowadays, solvents are used in large quantities in the chemical industry and chemical laboratories. The selection of solvents and subsequent waste-solvent management are based mostly on considerations of economy, safety, and logistics. Environmental concerns are often of minor importance for decision-makers. 

Capello, C., S. Hellweg, C. Seyler, and K. Hungerbiihler. 2005. Ecosolvent A tool for waste-solvent management in the chemical industry. 27th LCA Discussion Forum (17th November). Swiss Federal Institute of Technology. 

A section on solvent management, a crucial but oftenoverlooked detail all chemists should be aware of... 

Cost Effective Solvent Management, Cost Effective Reduction of Fugitive Solvent Emissions, Cost Effective Separation Technologies for Minimising Wastes and Effluents, Monitoring VOC Emissions Choosing the Best Option. 

As part of society s increasing drive to minimise the impact it has upon the environment, we are now starting to see solvents managed responsibly by their users, with the consequence that emissions to the environment will be minimised. A result of this will be a decrease in the overall consumption of solvents over the next decade. Behind this simple trend lies an extremely dynamic situation in order to achieve the desired controls, some solvents will play an increasingly important role in state of the art, efficient systems whilst others will decline. Engineering controls (abatement systems) will be a part of this process of emission reduction along with reformulation to more efficient solvents and the development of new, high efficiency solvents suitable for use in low VOC materials. 

A generalized soil/solvent management process is shown in Figure 1.8. It may be (and should be) practiced with any (or all) of the five types of equipment above ... 

In summary, these process elements of soil and solvent management are much more straightforward than their counterparts in aqueous cleaning, but ... 

It is not necessary for the work chamber to be integral with the solvent management process. This is shown for a small system in Figure 2.23, and in Figure 2.24 for a large system. Note that the work chamber shape is not always the same shape as are the parts, as shown in Figure 2.24. 

Solvent Management in Externally Sealed Enclosed Machines... 

Solvent Management Airless Enclosed Vapor Degreasers... 

With halogenated solvents, only supernatant (immiscible) water can be efficiently removed, and all water reacts with the solvents . Management of the retained water level devolves to management of added stabilizers which sequester the reartion products of the water and the halogenated solvent — corrosive mineral acids. So the answer to the question above with halogenated solvents is to use acid acceptance test kits and always maintain the positive presence of at least 0.2% NaOH equivalent . ... 

During manufacturing of the cells, solvents are used. Although some of them are specified in the inventory of some studies, the environmental relevance is not analyzed in any of the studies due to the lack of detailed information. It is often not clear whether these solvents have a toxic potential or contribute to the creation of photochemical ozone. Therefore, further analysis on the solvent management (for instance, venting of solvent vapor to the atmosphere or condensadmi and recycling) is necessary. 

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