Maintenance, waste minimization

Reduced Emissions and Waste Minimization. Reducing harmful emissions and minimizing wastes within a process by inclusion of additional reaction and separation steps and catalyst modification may be substantially better than end-of-pipe cleanup or even simply improving maintenance, housekeeping, and process control practices. SO2 and NO reduction to their elemental products in fluid catalytic cracking units exemplifies the use of such a strategy (11). 

M7 Improved Housekeeping, Training, Inventory Control (e.g., alter maintenance frequency institute leak detection program improved inventory control institute training program on waste minimization)... 

In most cases, cleaning costs are included with other maintenance expenditures. As a result, the actual costs associated with cleaning are not visible to plant management, possibly reducing its support for waste minimization. Often, however, when management learns of the true expenditures, actions to lower cleaning costs are quickly initiated. 

The principal feed to the HLW concentrator is the HLW stream from the contamination solvent extraction cycle. This typically contains about 2.5 M HNO3, 3-9 g FPs L L and 400-1200 Ci L"k and generates heat at the rate of 2.6 W L"L Additional feed may be intermediate-level waste concentrate and nitric acid evaporator bottoms. The HLW concentrator is usually operated at subatmospheric pressure and made of corrosion-resistant material such as titanium to extend life and minimize maintenance. Wastes are concentrated as far as possible without appreciable solid formation. If solids other than FPs are absent, a concentration of about 90 g FPs per liter can be obtained. Products are contaminated nitric acid overhead, slightly under 2.5 M, and evaporator bottoms, about 7 M in HNO3. Because evaporator bottoms self-heat at a rate up to 1 °C mn", the evaporator and the bottoms storage tanks must be provided with reliable cooling (Benedict, Pigford, and Levi, 1981,489). 

Modification of Equipment. (/) Install equipment that produces minimal or no waste. 2) Modify equipment to enhance recovery or recycling options. (I) Redesign equipment or production lines to produce less waste. (4) Improve operating efficiency of equipment. (5) Maintain strict preventive maintenance program. 

Velocity flame stoppers have been used for feeding waste fuel gas to furnace burners when the gas can become flammable due to contamination with air. They have also been used for feeding waste or depleted air streams to furnaces when the air streams can become contaminated with flammable gases (Howard 1982). It should be noted that a furnace pressure transient may render this device ineffective and consideration should be given to providing an upstream detonation flame arrester. In this arrangement a demand will only be placed on the detonation flame arrester when the velocity flame stopper fails. Therefore, detonation flame arrester maintenance should be minimal. 

As the design becomes more detailed, the PH As will have to emphasize the safety of maintenance workers. The design should be configured to minimize the number of maintenance activities in contaminated areas to reduce worker risk and to ensure that workers in DPE suits can access the areas easily and safely. This precaution could also reduce the waste streams arising from DPE suits and decontamination solution used during maintenance activities. 

Researchers concluded that ion exchange removal of nitrate was cost prohibitive at the Livermore site because of the high cost of waste disposal. The perchlorate-only alternative with nitrate removal using another technology was the most cost-effective solution. Perchlorate disposal costs under this option were 350/year, and minimal maintenance of the treatment unit would be required (D20493D, p. 12). The cost estimates are summarized in Table 1. 

According to the developer, installation costs are low because no excavation or drilling is required, and no secondary waste is generated. Operating costs are minimal because the system requires no site power and the components need relatively zero maintenance (D192921, p. 3). 

These strategies will minimize wastes and save a plant money on maintenance and waste disposal. 

A program of good maintenance and repair is essential to minimizing these losses. Again, physical measures can be installed on a cost-effective basis, which include loadback bins at loss points to allow material to be recovered as product rather than as waste. Also, closed chutes and other conveyance devices, particularly at discharge points into railcars, will add greatly to loss control. 

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