Clean system concept

For many locations, the phosphonate/dispersant combination provides effective scale control without necessity of acidification. How does this type of treatment function as a corrosion inhibitor One possible explanation is that if a surface is clean, free from deposits of any type that can set up local concentration cells, then any corrosion occurring will be uniformly distributed and reduced in severity. This permits normal service life of system equipment. This approach to corrosion control is called the "clean system concept." Copper inhibitors (thiazoles and triazoles) function well in these combinations. Addi-... 

For this concept atmospheric gasification, with air as the gasification medium, has been chosen. In the future pressurised systems may be preferred. All main components of such a system do exist on the market gasifier, cleaning system, coir iressor, Fischer-Tropsch unit, gas turbine, and the steam cycle. Large-scale, as well as small-scale (15 to 100 MW ) systems belong to the possibilities. 

The pressurized bed was developed in the late 1980s to further improve the efficiency levels in coal-fired plants. In this concept, the conventional combustion chamber of the gas turbine is replaced by a PFBC. The products of combustion pass through a hot gas cleaning system before entering the turbine. The heat of the exhaust gas from the gas turbine is utilized in the downstream steam turbine. This technology is called PFBC combined cycle (Figure 22.8). 

Currently used mathematical models of gas purification formed on simplified theoretical concepts of gas flow. They are not sufficiently taken into account the operational and design parameters of gas cleaning devices, as well as aero-hydrodynamic properties of gas-dispersed flows. These models cannot be used to search for the best options of integrated gas cleaning systems, as they show the properties of objects in a narrow range of parameters. We need more complete and appropriate mathematical models based on the study of the aerodynamics of gas and taking place in these events. 

In developing the concept of a heat transfer coefficient, we moved away from physics and into the realm of engineering science. Equation (4.15), which is applicable to a clean system, was developed. In it, allowance is made for the thermal resistances within the fluid films and the resistance of the intervening tube wall. However, all industrial systems contain impurities and some will be deposited on the heat transfer surfaces in the form of thin dirt films, which being of low thermal conductivity will generate additional thermal resistances. These films build up with time and the heat exchanger must be sized so that the performance is satisfactory throughout the complete period of operation. 

Also, since this company has been a meticulous applier of the 5S system, those system concepts are overriding in the lean process. (In this company s usage, 5S is defined as sorting, simplification, systematic cleaning, standardization, and sustaining). It was said by a senior executive at this location that if the staff has not been educated in 5S concepts and believe that their substance is a core value, you can forget about lean. You must have established a stable environment in which waste elimination is a fundamental to move into the next step to accomplish lean. ... 

Crowe et al. ° also patented a foam cleaning system that used a fluorocarbon carrier and a stabilizing agent containing a perfluoro alkanesulfonamide. The system incorporated the concept of foam recycle, and the formulation could contain nitric acid to remove hydrocarbon deposits. 

The NHDD project is aimed at the design and construction of a nuclear hydrogen demonstration system for demonstration of massive hydrogen production and system safety. A VHTR systems concept study has been performed for 3 years since 2011. The main objectives of this smdy are to develop the VHTR systems concept for nuclear process heat and electricity supply to industrial complexes, for the massive nuclear hydrogen production required to enter into a future clean hydrogen economy, and to establish the demonstration project plan of VHTR systems for subsequent commercialization. 

Ultrasound can thus be used to enhance kinetics, flow, and mass and heat transfer. The overall results are that organic synthetic reactions show increased rate (sometimes even from hours to minutes, up to 25 times faster), and/or increased yield (tens of percentages, sometimes even starting from 0% yield in nonsonicated conditions). In multiphase systems, gas-liquid and solid-liquid mass transfer has been observed to increase by 5- and 20-fold, respectively [35]. Membrane fluxes have been enhanced by up to a factor of 8 [56]. Despite these results, use of acoustics, and ultrasound in particular, in chemical industry is mainly limited to the fields of cleaning and decontamination [55]. One of the main barriers to industrial application of sonochemical processes is control and scale-up of ultrasound concepts into operable processes. Therefore, a better understanding is required of the relation between a cavitation coUapse and chemical reactivity, as weU as a better understanding and reproducibility of the influence of various design and operational parameters on the cavitation process. Also, rehable mathematical models and scale-up procedures need to be developed [35, 54, 55]. 

With this encouraging result from the model system, a gram quantity of the racemic sulfoxide 40 was prepared by oxidation of benzoxathiin 16 with mCPBA and a small amount of chiral sulfoxide (A)-40 with 94% ee was isolated by subsequent chiral HPLC separation (Scheme 5.12). When chiral sulfoxide (S)-40 was treated with borane-dimethylsulfide, a clean reduction of the olefin and the sulfoxide was observed. More surprisingly, only the desired cis-diaryl dihydrobenzoxathiin 12 was observed in high yield and unchanged 94% ee. No trans-isomer or 16 was observed. With this proof of concept in hand, an efficient... 

The latter concept implies providing local life support systems for unfriendly environments. By now, Ukrainian scientists and engineers have developed a variety of processes for potable water treatment by adsorption, electrochemical oxidation, electrocoagulation, electro-coprecipitation, electrodialysis, electrofloatation, floatation, membrane techniques etc. Each family must get small units for water purification, air cleaning and removal of hazardous substances from the food as soon as possible, for it may take decades to introduce cleaner production on a national scale. Here, we should follow the example of Western business people who bring with them to Ukraine devices enabling a safe existence in this unfriendly environment. 

The results presented here demonstrate the first successful applications of the concept of electroenzymatic synthesis. However, it is also obvious that many more systems are potentially very interesting for synthetic applications. This area is wide open for further creative research and only the tip of the iceberg has surfaced. What is especially promising is the fact that electroenzymatic synthesis is an environmentally friendly technique using the electrode as a clean reagent and the enzymes for high selectivity. Closed systems for technical applications are easier to realize than in many other areas. The author is convinced that industrial syntheses of valued small scale products will be seen in the near future. 

Arnold, K.E. "Design Concepts for Offshore Produccd-W ater Treating and Disposal Systems. JPT(Feb. 1983) 276-83 Burke, R.G Clean-up of Oil Water Poses a Challenge," Offshore (Sept. 1985). 

Similar factors have been developed for bubble columns, which includes the concept of gas hold-up eG, the fraction of the reactor liquid volume occupied by the gas dispersed in the liquid phase. The number of such factors can be reduced when comparing the mass transfer of just one compound in the same liquid/gas system, e. g. for oxygen or ozone transfer in clean water/air systems the above relationship reduces to the first three terms. 

Fourth, the concept of a background bromine biostat, coupled with a flexible nonoxidizing biocide program, has provided the basis for clean cooling systems, with minimal biofilm formation and algal slimes. 

The concept of precommission cleaning and passivation is not new it has been promoted since the earliest days of water treatment. However, in the global marketplace, it continues to be a deplorable situation in that there are still far too many newly constructed cooling systems inadequately precleaned (if cleaned at all), or given proper passivation protection, prior to start-up and plant commissioning trials. Poor standards of cleaning may,... 

For a WFI or highly purified water system, the SIP/CIP method is usually applied. In an SIP/CIP system, sterilization and/or cleaning take in place in situ or without dissembling the equipment. Consequently, the result of sterilization and/ or cleaning is confirmed by the process parameters previously validated. Based on process parameters and their ranges previously determined by the process validation, the SIP/CIP process can be confirmed whether or not it is completely sterilized and cleaned. This is a typical application of the concept of validation. 

In the air handling system, special attention has to be paid to keep the environment clean and to prevent the contamination of products. There are two different kinds of concepts to control the air system one is to prevent intrusion of the surrounding air (positive air pressure control), and the other is for the containment of air containing an undesirable substance generated in the operation area (negative air pressure control). Air handling systems should be designed, installed, and maintained to meet these purposes. 

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