The high temperature heat of the earth and groundwater


10/03/2012

The high temperature heat of the earth and groundwater observed in the vast majority at great depths - 3,000 feet or more.

However, the high cost of construction of wells (70 to 90% of fixed assets) imposes restrictions on the structure on the basis of geothermal fields of geothermal heat or power stations.

The following are the specific capital costs in geothermal wells, rub. / M (the scale of prices in 1982), which are defined according to the geographical area and the depth of drilling by the formula [5]

,

where - the constant coefficients that depend on the geographic area to be taken from Table 3 - drilling depth, km - coefficient depending on the rate of penetration (at commercial speed achieved when the rate of 2 times).

Table 3 - Values of the coefficients ? and ?

The geographical area

?, rub.

?, rub./km2

Siberia, Northern Urals, Sakhalin

Kazakhstan, Central Asia

Ukraine

Azerbaijan, Georgia, Dagestan

Krasnodar and Stavropol

75 - 80

65 - 70

50 - 55

55 - 60

40 - 42

9 - 8

6 - 4

6 - 5

5 - 4

1.7 - 1.2

With such percentage value in geothermal wells stations to determine at least three tasks:

- To develop a new methodology for the identification of high-temperature geothermal fields;

- To develop the technological regulations to substantially increase the life of the wells not only on an annualized basis, but in hours;

- To achieve more efficient use of geothermal heat each particular geothermal field with the local climatic conditions.

The need to develop new techniques to identify high-temperature geothermal reservoirs due to the fact that the underground water due to more than rocks, heat capacity, and the mobility can significantly alter the structure of the geothermal fields. In particular, this refers to the vertical movement of the ground water (fluids).

Omitting the mathematical formulation of the problem of determining the redistribution of heat in the sediments, the boundary conditions, the very mathematical model and its solution of equations, which are given in reference [6] reproduce this book only in Table 4, which shows the results of the calculation, changing the face of large areas of geothermal fields during vertical movement of groundwater.

Table 4 - Temperature increment at the top of the reservoir depending on the fluid flow velocity

(L2 - L1) *, m

The increment in the top of the reservoir temperature, ? C (heat flux density of 41.8 mW/m2), with the fluid velocity, cm / year

0.5

1

5

10

50

100

250

1.1 (0.8)

2.2 (1.7)

5.9 (4.6)

2.2 (1.7)

4.9 (3.8)

12.4 (9.6)

12.4 (9.6)

27.0 (21.0)

87.5 (68)

27.0 (21.0)

63.7 (49)

280 (217)

* (L2 - L1) - vertical movement of groundwater at depths; L2 - the depth of the seam roof

As can be seen from Table 4, the vertical movement of groundwater may in some cases completely change the face of geothermal fields. As shown in Table 4 (which shows the calculations for L2 = 2,700 m, q = 56,0, ? = 2 W / (m


As sandwich panel is made?
Purchase and sale, barter over the Internet
Health starts with the kitchen
Life behind the screen
Non-standard advertising vehicles - fresh solutions in the advertising industry