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Is Business Conducted to Save Lives?

Posted on by Pakast Drilling

The experience of PAKAST TECHNICAL SERVICES cooperation with the Australian company Armor Energy through Teclab Limited turned out to be devastating rather than profitable.

In September 2021, 325 seismic wells were drilled in Uganda under the contract with Teclab Limited, the contractor to Armor Energy. PAKAST seconded the best drilling crew to the project for timely and high-quality fulfillment of contractual obligations.

Many of the company’s ongoing projects facilitating people with water were suspended.

However, until now Teclab Limited has not paid to the contractor for the works performed.

It is strange to think that the headquarters of such a large company as Armor Energy (which is very far from Africa and can enjoy all the benefits of civilization) cannot control the financial obligations of its contractors and payments under the contracts to subcontractors, and cannot responsibly manage its exploration projects.

Is business conducted for the sake of lives of those fortunate enough to be born in a prosperous country? Does this give the right to exploit other people who work under the scorching sun with the dream to simply give their children a better life than theirs? I would like to believe that the days of such business are long gone and that the current situation is only a system failure, which will be addressed in the nearest time possible.

Is water extraction in Africa a business or a mission? Limited water resources, scorching sun, thirsty children … Drilling water wells in this region requires skills, knowledge, professional expertise and reliable technologies.

The African drilling company PAKAST TECHNICAL SERVICES has been drilling wells in Uganda for many years, helping to organize an efficient water supply system in the country.

The company’s employees are 100% local specialists, indigenous Africans who can support their families at a decent level with the money they make, which means they can contribute to economic development of Uganda.

Business provides water and bread to the African people. This is a local business for local people.

What happens when a large international client appears offering a large order corresponding to the company’s expertise?! Naturally, the order is accepted. This means recognition of the company’s professional level, a new stage of development, and, therefore, greater prosperity for employees … This should be the case according to the laws of normal business.

Search for gold deposits in Africa | Core Hammer

Posted on by rik
In this article, I will tell you about the drilling technologies that Pakast Technical Services limited uses to search for mineral deposits in Africa, for example, gold. How to take samples in hard rock without using specialized diamond drilling rigs or RC-type drilling rigs? Your project is at the stage of geological exploration and you do not want to incur the costs of expensive diamond drilling or RC drilling, then pay attention to the following drilling technologie that I will tell you about now. Core drilling air hammer is carried out using the air supplied through the rods with a reciprocating piston a so-called air hammer Used as the drilling mechanism rotating the drilling bit, core pipe, the implementation of which results in the destruction of the rock within a ring pattern.

Design water borehole.

Posted on by rik

In the previous article we discussed in detail in which rocks the water is. Now we are going to design the structure of the water borehole.

Let’s look at our engineering calculations to design a water borehole based on your water needs, and still get the minimum cost of the borehole.

Let’s start with calculating the capacity of a four and five inch casing screens.  Let’s calculate the screens productivity from five to twenty five cubic meters per hour.  The length of the UPVC type filter pipe is three meters.  The slot area of the total filter surface area is three percent.  We determine the rate of water entry into the casing screens from the water layer according to the formula:

V = screen entrance velocity (ft/sec)

Q = well discharge (gpm)

r = radius of well screen (in)

b = length of well screen (ft)

P = percentage open area of the screen

Recommendations for maximum well entrance velocity range (Groundwater and Wells, Second Edition, Johnson Screens) to 1,5ft/sec = 0,457 m/sec (AWWA, 2015).

The Calculation of Yield for casing screens five inches (140 mm)

The resulting calculations can be seen in the table, we can see that the calculated input speed for the screen five inches within the acceptable values, it is less than the upper limit of one and a half feet per second, recommended by the standard.

Next, we will compute the productivity for a four- inch screen (114 mm).

The designed inlet velocity is also less than the upper limit recommended by the standard for four-inch casings, up to twenty-five cubic meters per hour.

As we can see from the calculations, the usage of even one casing screen of three meters long provides the possibility of normal borehole operation with the yield of up to twenty-five cubic meters per hour. The thickness of water layers in Uganda is ten meters or more. So, it is possible to install three casing screens pipes of three meters long into the well with this thickness. Therefore, there will be a triple margin of the possible productivity of the borehole.

The most important parameters on which the cost of a borehole depends are its length and diameter.  Justification of the minimum diameter of the casing screens, which ensures the design selection and the allowable reduction, allows to reduce the cost of the well, taking into account the fact that modern borehole pumps provide a wide range of capacities and pressures at a small outer diameter.

The cost of a borehole pump will also depend on several factors: the type of pump, the capacity and the diameter, and an increase in diameter will lead to a price increase.

Based on the criteria of water entry speed in the screen of 1.5 feet per second, we can recommend to use a four-inch column, for boreholes with a design capacity of up to 25 cubic meters per hour, which will provide the required productivity for many private boreholes in Uganda. The final decision should be made by taking into account the real hydrogeological conditions of the projected well.

An eye-opening example of pumping equipment for a four-inch borehole is a three-inch solar aquifer pump. 

You can contact the office of a professional drilling company PAKAST TECHNICAL SERVICES to get more information about the cost of drilling boreholes with a four-inch casing running, and the cost of a three-inch pump of a solar water system.

The recommended minimum gap between the casing screens column and the borehole wall (annular space between the borehole well and casing) is one inch (Roscoe Moss Company, 1990, Handbook of Groundwater Development, John Wiley & Sons, Inc.).  Accordingly, the diameter of the bit for drilling under the filter column four inches will be at least one hundred and sixty-five millimeters.

HOW TO ENHANCE THE BOREHOLE YIELD

Posted on by rik

I will tell you how to enhance the yield of the borehole with minimal costs.

During operation, the productivity of the borehole water intake decreases. The main reason for the decrease in flow rate is clogging of the bottom. To rise productivity to the initial value, clean the screens and borehole. But cleaning the borehole will not help if the flow rate was initially low the reasons for this may be different. Now, I would like to tell you about the easiest way to install a sealed head on the borehole.

 

Atmospheric pressure at sea level at a temperature of zero degrees Celsius is considered to be seven hundred and sixty millimeters of mercury. Knowing the density of water and the density of mercury, you can find out that seven hundred and sixty millimeters of mercury are equal to ten meters thirty-three centimeters of water column knowing this, let’s think about how you can increase the borehole yield.

 

Everything is very simple we fill the borehole to the top with water and quickly put a sealed borehole head, this action we sort of remove atmospheric pressure from the borehole.

 

If the static level was equal to fifteen meters, then we removed the atmospheric pressure, which is equal to ten meters of water column, then the static level rises to five meters, and the dynamic level also rises by ten meters.

 

It turns out that after sealing the borehole, the water column from the static level to the top of the filter, for example, will not be forty but fifty meters, then the yield of the borehole will Increase by twenty-five percent. It turns out that the smaller the distance from the static level to the top of the filter, the greater the performance gain we get

t should be mentioned that one of the disadvantages of this method, on newly drilled boreholes with a casing on a threaded connection is that this technique most likely will not work. This is because the threaded connections will not provide one hundred percent tightness during the first two months and the load on the screen will also rise. However, if the choice is between increasing the production rate of an existing borehole or drilling a new one, this will be the best option.

 

As for the sealed head, it consists of two plates between which there is a rubber spacer made of thermoplastic elastomer. It is installed for less than a minute and a conventional spanner wrench is enough for mounting. When tightening four bolts which  located around the perimeter of the plates, the rubber squeezes due to which the spacer in the cross section  increases in size and fills the voids between the casing, UPVC pipe, and electrical cable.

Search for groundwater.

Posted on by Pakast Drilling

Groundwater is the main source of fresh drinking water for humans.  The science of groundwa-ter is called hydrogeology.  Most of Uganda lies on igneous and metamorphic rocks of the crys-talline basement bedrocks basalt, granite, quartzite, shale, mudstone.

Firstly, the surface water is contained in the near-surface loose part of the section, these are soil waters.  This water occurs at a depth of up to ten meters, in the first sedimentary layer of the rock.  It has a direct connection with the surface is collected due to precipitation and is not fil-tered by soil.  Surface water not drinking water turbid with sediment.  Not used for water supply.

 

Second type.  Subterranean is water in the weathered rocks.  Rocks, sands, clays, shale, grav-el.  The waters of the weathering crust lie at a depth of 10 to 80 meters, in a layer of rocks of medium density.  Groundwater of this type can be fed by infiltration seepage into the depth of the upper water over the entire area of the aquifer.

 Third type.  Fissure veins groundwater is water in basement rocks.  Fractured veins free flow-ing underground waters occur at a depth of fifty to two hundred meters, in a layer of bedrock sol-id rocks.  

These waters are well filtered and protected from surface contamination by loose sediments lo-cated above (waterproof layer).  They do not contain sandy, clayish impurities.  Almost always suitable for domestic and drinking water supply.

We drill wells for water types 2 and 3 as tap water, and, accordingly, wells are drilled on these horizons.

 Before water well drilling, it is important to pre-determine the location of drilling, since aquifers are not common everywhere. To find water on the site, we use the method of electrical sounding. 

It is used when searching for groundwater and determining the position of aquifers, assessing the depth of their occurrence, which is necessary to select a location for water well drilling.

 

 

 

We use electric water detectors, specially designed for the exploration and development of water resources, data from which are processed and interpreted by software, and transmitted through a phone or tablet with the ability to display color graphics.  It is convenient, fast and accurate.  The results in the form of a graphic image can be immediately presented to the Customer within five minutes.

Low frequency current is used for vertical electrical sensing when searching for water.  For these purposes, electrodes are clogged in different parts of the site, to which an alternating volt-age is applied.  Then the resistivity is measured.  The specific electrical resistance of the aquifer and rocks is different.  Soil saturated with water always has a lower electrical resistance.  Most of the geophysical instruments brought to Uganda use a manual method of processing the data obtained, which risks misinterpreting the data by a geophysicist.

  Geophysical methods help to establish the position of the aquifer, to estimate the thickness of the overburden, and to find the water-resistant layer at depth.  This information will help us to es-timate the cost of drilling a well, and most importantly, you will minimize the risk of drilling a dry borehole.

 

 Ninety-seven percent of the water that is on planet earth belongs to the salty oceans and seas.  And only three percent is fresh water.  Love and protect clean water.