Waste fluids

Because systems are normally not designed for use with this type of fluid, certain aspects should be reviewed with the equipment and fluid suppliers before a decision to use such fluids can be taken. These are compatibility with filters, seals, gaskets, hoses, paints and any non-ferrous metals used in the equipment. Condensation corrosion effect on ferrous metals, fluid-mixing equipment needed, control of microbial infection together with overall maintaining and control of fluid dilution and the disposal of waste fluid must also be considered. Provided such attention is paid to these designs and operating features, the cost reductions have proved very beneficial to the overall plant cost effectiveness. 

Heat exchangers for liquids will be double pipe, shell-and-tube and plates (see Figures 6.3, 6.4 and 17.1). Waste fluids may be contaminated by the process, and heat exchangers for such fluids must be cleanable, and kept clean. 

Figure 29.2 shows the mineralogic results of the calculation. Dolomite dissolves, since it is quite undersaturated in the waste fluid. The dissolution adds calcium, magnesium, and carbonate to solution. Calcite and brucite precipitate from these components, as observations from the wells indicated. The fluid reaches equilibrium with dolomite after about 11.6 cm3 of dolomite have dissolved per kg water. About 11 cm3 of calcite and brucite form during the reaction. Since calculation... 

The use of open pits or ponds for evaporation of brine is widely practiced in southwestern states where evaporation exceeds precipitation [23]. For example, about 75% of all oil and gas waste fluids are disposed of by evaporation pits in New Mexico [30]. Evaporation ponds require large land areas, and they may contaminate groundwater. Today regulators view evaporation pits with disfavor because faulty pond design and operation have allowed salts to migrate into usable groundwater reservoirs [9]. 

Strongly radioactive waste fluids are stored in safe-tanks which are simply long, small-diameter (e.g., 20 m by 10 cm) slightly sloping pipes. To avoid sedimentation and development of hot spots, and also to insure uniformity before sampling the contents, fluid is recirculated in these pipes. 

Many older power plants still do not have injection wells and a waste fluid piping system. Various methods have been employed to... 

To exploit the heat stored in the rock, it is important to have cooler water recharging the reservoir. The recharging water gains heat by flowing through the hot reservoir rock towards producing wells and it extracts heat from this rock in the process. The recharge of the water may be natural. Alternatively, it may be injected waste fluid. 

Geothermal reservoir rocks are typically fractured and therefore exhibit variable and anisotropic permeability. For that reason it is neither possible to predict with confidence how an injection well may perform with respect to its injectivity nor with respect to which way the injected fluid will flow once it is in the reservoir. Because of this complication, the success of injection varies between fields and it is anticipated that a special injection scheme must be developed for each field depending on its characteristics, mainly the three-dimensional distribution of permeability and the waste fluid composition. Injection may require drilling of special wells. Alternatively, wells drilled for the purpose of production may not have adequate yield but can be used successfully as injection wells. When this is the case, no special wells need to be drilled for injection purposes, which reduces road building and therefore scenery spoliation. 

Injection underground does not necessarily require injection into the geothermal reservoir from which production is derived, because this process carries with it the risks of potential cooling of the production wells and possible adverse impacts on the geochemical characteristics of geothermal fluids. The waste fluid may also be injected into an aquifer other than the geothermal reservoir simply to avoid... 

In the Palimpinon geothermal field in the Philippines, where waste fluid has been injected for some years, re-injected fluid has already returned into the production wells, as indicated by an increase in the salinity of the water produced. Harper Jordan (1985) report an increase in Cl concentration in a large number of production wells of the Palimpinon field. This response to re-injection was observed only three years after re-injection operations started. The increase in Cl is different for each of the production wells and reflects the amount of the reinjected fluid returning to each of the wells. 

Unless otherwise used, the waste heat due to power generation ultimately ends up in the atmosphere or hydrosphere. The latter appear to be unlimited heat sinks however, local conditions like the microclimate can be significantly influenced. Therefore, the best solution to avoid atmospheric and hydro-spheric discharge is the underground disposal of the waste fluids or use of the waste heat... 

Significant amounts of waste heat arise from geothermal energy utilization the amounts vary with the utilization type. The possibilities of waste heat disposal are often limited by technical or legislative barriers. For technical reasons, re-injection of used geothermal fluids into the subsurface often remains incomplete. Regulations, on the other hand, can restrict discharges of waste fluid and heat to (or dissipation) in the environment. A beneficial way of waste heat treatment is the use of the heat for purposes that can even result in economic profits. Several such options have been described above but many more possibilities are technically feasible and economically viable. 

Fig. 5. In a double-flash plant for producing electricity from hydrothermal water, superheated water is delivered from the well, A, to an initial flashing unit, B, where the pressure is reduced to release steam which drives a turbine, D. The liquid fraction is then delivered to a second flashing unit, C, where further pressure reduction produces more steam which is introduced to the turbine at an intermediate stage. The waste fluid from the second flashing stage, E, may contain very high concentrations of dissolved or suspended solids, presenting significant disposal problems. The spent steam can be recondensed and...

Finished Product Waste Fluid (Heat Transfer) Solvent Water D C B... 

Krzycki and Zeikus (11) reported that the highest corrinoid level of 5.6 mg/ L was obtained from Methanosarcim bakeri strain MS using MeOH as substrate. The results presented herein show that alcohol waste fluids utilizing acclimated meth-anogens have a lower level of corrinoids. Methanolmaybe considered a stimulatory factor, and additional studies are in progress. 

Although the waste fluid was low in calcium (about 3 ppm), it was calcium tagged in the aquifer. This was actually expected because of the reaction of the acid waste (pH 5, and later pH 3) with the aquifer limestone. 

The rapid increase from 26 to 98% waste fluid in the deep monitoring well indicated that the nonneutralized waste dissolved the aquifer carbonates and developed a highly conductive karstic system, which was very alarming in terms of waste disposal in the aquifer. During all this time no chemicals arrived in the upper monitoring well. 

III. The Magnetic Field Effect in the Treatment of Waste Fluids and Effluents... 

The currently most important applications of magnetic fields to environmental protection are in the area of waste-fluid and effluent treatment, involving several industrial sectors open-hearth furnaces, gas scrubbers, steel mills, converters, mines, power- and nuclear plants, leaching operations and metal recovery are major examples. The removal of particles via filtration and coagulation in magnetic fields has, in fact, a well established technology on its own. 

The magnetic field effect in the treatment of waste fluids and effiuents 605... 

The bioreceptor does not have to be an enzyme or antibody, virtually any compound that exhibits molecular recognition for an analyte is suitable. This could be a piece of DNA, a cell, a microorganism, an organelle or a plant or even mammalian tissue. Enzymes and antibodies are used most often, as they are relatively simple to incorporate into a device. This is more difficult with tissue slices and biological cells as they must be supplied with nutrients and have waste fluids removed in order to keep them alive. 

Drainage and containment of waste fluids resulting from the decon operation are captured and stored here. 

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