Clean Sand

Very clean sands are rare and normally variable amounts of c/ay will be contained in the reservoir pore system, the clays being the weathering products of rock constituents such as feldspars. The quantity of clay and its distribution within the reservoir exerts a major control on permeability and porosity. Figure 5.2 shows several types of clay distribution. 

Laminae of clay and clay drapes act as vertical or horizontal baffles or barriers to fluid flow and pressure communication. Dispersed days occupy pore space-which in a clean sand would be available for hydrocarbons. They may also obstruct pore throats, thus impeding fluid flow. Reservoir evaluation, is often complicated by the presence of clays. This is particularly true for the estimation of hydrocarbon saturation. 

Gives very clean sands and has relatively low hydraulic water requirements (0.5 t/t underflow). One of the most efficient single-stage classifiers available for closed circuit grinding and washing. Relatively expensive. 

In some countries, mounding is used instead of conventional insulation. The tank is completely covered with clean sand or other clean material. Portions of the covering must be removed from time to time so that the outside of the tank can be inspected. 

Give the boundaries of the clean sand. Are some zones shaly ... 

Armour wrapping In rocky ground it has always been considered good practice to pad the trench for a buried pipeline with clean sand. This procedure can be very expensive if the sand has to be hauled long distances, and an armour wrap has been developed to supplement the normal outer wrap to meet such conditions. 

Soil mixture forget the vermiculite from now on. It holds too much moisture and makes for saturated, unhealthy soil. 1 suggest the following A coarse clean sand, A perlite, A sterilized loam, and A milled peat. If this seems too light, increase loam and peat. Some sterilized organic compost, screened, may also be added for nutrition. 

Assemble an apparatus as shown in Fig. 79. Fill U-tube 2 with phosphoric anhydride applied onto glass wool. Put a mixture consisting of 5-7 g of dry lead nitrate and a small amount of clean sand into test tube 1. Immerse U-tube 3 into a cooling mixture (ice and... 

After the mixture has been allowed to stand at room temperature for at least an hour (Note 11), a few grams of clean sand are added and the dark red mixture is filtered with suction. The filtrate is extracted with ether (100 ml., then 4-5 portions of about 30 ml. each), and each extract is used in turn to extract the filter cake. 

The top of the column is frequently covered with a circle of filter paper or a layer of clean sand to prevent disturbance of the surface during subsequent loading. A suitably concentrated solution of the mixture is added from a pipette, the liquid is allowed to drain just to the surface of the adsorbent and the inside of the tube is rinsed with a small quantity of the solvent which is again allowed to drain just on to the column. Finally the column space above the adsorbent is filled with solvent and a dropping funnel filled with solvent is attached. 

In a tall 1-1. beaker is placed an intimate mixture of 53 g. (0.25 mole) of freshly prepared acetophenonephenylhydrazone (Note 1) and 250 g. of powdered anhydrous zinc chloride (Note 2). The beaker is immersed in an oil bath at 170°, and the mixture is stirred vigorously by hand. The mass becomes liquid after three to four minutes, and evolution of white fumes begins. The beaker is removed from the bath and the mixture is stirred for five minutes. In order to prevent solidification to a hard mass, 200 g. of clean sand is thoroughly stirred into the reaction mixture. The zinc chloride is dissolved by digesting the mixture overnight on the steam cone with 800 cc. of water find 25 cc. of concentrated hydrochloric acid (sp. gr. about 1.2). The sand and crude 2-phenylindole are removed by filtration, and the solids are boiled with 600 cc. of 95 per cent alcohol. The hot mixture is decolorized with Norite and filtered through a hot 10-cm. Buchner funnel, and the sand and Norite are washed with 75 cc. of hot... 

Collection efficiencies were determined by spiking 1-g samples of clean sand with about 18 pg of each component, and extracted using supercritical CO2 at 400 atm and 50°C at a flow rate of 0.6 mL/min. 

Supplies Put 5 cc. of water in a test tube and slowly pour upon it 15 cc. of concentrated sulphuric acid. Cool the acid by holding the test tube in a stream of cold water. Put 5 to 7 cc. of alcohol in the test tube A, add a little clean sand, or a few glass beads, and then slowly pour in the cold acid. Two or three small bottles will be needed. A dish should stand under A to catch the contents, in case of accident. 

Equable heat at a higher temperature than 100° C. may be conveniently obtained by using a sand bath. This is simply a shallow iron pan (Fig. 91) filled with dry, clean sand and supported on the ring of an iron stand or on a tripod. The dish to be heated is partly... 

For clean sand with intergranuleir porosity and for brine saturation Sw<100% the resistivity index versus brine saturation is obtained from Archie s equation [5] ... 

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