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Oil refining process. Crude oil just extracted from the well in its original form has a very limited application. Therefore it is processed before it arrives on the market in the form of gasoline, fuel oil, aviation fuel, etc.

In the early stages of the oil industry the refining process was reduced to primitive distillation. The “black gold” was brought to the boiling temperature, with condensation of the oil products at different boiling points. Nowadays, oil refining is influenced by technological progress, and at the same time by the tightening environmental regulations.

The process of oil refining is as follows:

1. Preparation of crude oil for processing;
2. Primary crude oil processing;
3. Re-refinery;
4. Refining.

Preparation of oil for refining includes optional dehydration and salt removal to reduce corrosion of equipment and improve the quality parameters of oil.

The composition of crude oil includes various hydrocarbons, each of which has its value. That is why in the first stage the crude oil is separated into components by high temperature distillation. This method works because each component has a different condensation temperature and it can be condensed separately. Some of these components are ready to be delivered to the market. Other components are subjected to further processing to receive more expensive oil products.

Simple distillation removes small particles and adjusts oil chemical properties. The more complex transformations such as cracking and conversion is performed at large oil refineries. They produce higher quality oil such as petrol, and reduce the output of cheap oil such as black oil fuel and asphalt.

Oil refineries are located in close proximity to the source of raw material, oil pipelines, distribution points, and available labor and energy resources.

Compressor oil is used in the industry as a lubricant for the valves and cylinders of compressors; it is also used as a sealing medium for compression chamber and piston rods.

The main feature of that distinguishes compressor oils from other industrial oils is their operation in high-temperature environments and mixing with coolants. Therefore, compressor oils need to meet stringent requirements regarding chemical and thermal stability, as well as viscosity at low temperatures.

Compressor oils can be medium-load and heavy-duty. The medium-load air compressor oil doesn’t have additives. The heavy-duty compressor oil is produced from sulfur and low-sulfur petroleum by deep selective refining, followed by mixing with special additives, oxidation inhibitors, corrosion inhibitors, antiwear additives, etc.

When selecting a particular oil, it is necessary to pay attention to pour point (must be low), viscosity index (must be high), the possibility of chemical interaction with a coolant, their mutual solubility, and corrosion activity of the mixtures.

The parameters of HA-23 and HF-12-16 compressor oils (Table 1).

Table 1

Purification of compressor oils

Compressor oils containing water, solids and dissolved gases have significantly degraded performance properties. Their use therefore is highly undesirable. But it does not mean that the life cycle of the oil ends.

GlobeCore developed plants for purification and regeneration of compressor oils which remove water, dissolved gases and mechanical impurities. After processing, the compressor fluid has the initial properties, and can be reused for its intended purpose.

Сompressor oil purification equipment from GlobeCore:

• Reduces water content to 10 ppm or less;
• Reduces air content not 0.25% or less (vacuum degassing);
• Removes solid impurities to 1 micron;
• Extends lifetime of oil and compressor;
• Increases efficiency of compressors;
• Reduces downtime.

Silica gel. The industry uses various adsorbents to remove excess moisture. Today, there are many types of adsorbents of natural and synthetic origin. A special place among the adsorbers belongs to silica gel.

Silica gel is a dried gel obtained from oversaturated solutions of hydrated silica. The main feature of silica gel is its large specific surface area of approximately 1000 m2 / g. Silica gel is available on the market in the form of grains and spherical  granules.

Silica gel is widely used for drying:

• air
• industrial oils;
• carbon dioxide;
• hydrogen;
• chlorine;
• nitrogen.

It is also used for protection of equipment against corrosion.

After the adsorbent is saturated with moisture, it must go through a process of drying to be returned into service.

To solve this problem, GlobeCore has developed the SSZ-15B drying cabinets. They are designed to remove water from sorbents with particle size of not less than 1 mm.

The drying cabinet is equipped with a fan that ensures even distribution of heat through the layers of the dried material. The timer allows to hold a specified temperature during a preset time.

Comparing with the previous models, SSZ-15B has the following advantages:

• Operates at temperature up to 400 ° C;
• Maintains preset temperature;
• The door screw lock improves pressure sealing and eliminates paint stripping;
• Oven trays are removable, thus the cabinet can be used for preheating, heat strengthening and baking of other materials and parts.

The customer can request heating elements of up to 800 ° C, as required for the production processes, and a furnace temperature control system protecting the operator from burns.

Diagnosis of power transformers helps to identify potential problems and failures in order to prevent and remove them.

It is recognized that the analysis of breakdowns of transformer insulation also detects anomalies in oil-filled equipment. For example, when metal parts of the transformer are overheated, the oil accumulates gases, carbon and metallic particles. The most dangerous of them for the insulation system are conductive particles of carbon and wet fibers. Some faults are the result of oil contamination with solid particles. It depends on the amount, size and origin of such impurities. Hence, the analysis of oil contamination gives valuable information about the condition of the transformer.

The low flash point and the increased acid number indicate high local overheating and destruction of insulating liquid. The dielectric breakdown and an increase in dielectric tangent loss confirm the presence of moisture in the insulation system.

Diagnosis of power transformers. Acid number is also an important diagnostic parameter. It characterizes the presence of acid and oxidized products of aging paper insulation, which accelerate the formation of sludge in the oil. The maximum acid number is 0.25 mg KOH / g. The recommended value for fresh transformer oil is no more than 0.03 mg KOH / g.

Starting up a transformer after a long break in the cold season could have the dielectric strength reduced more than twice.

The most dangerous thing for the insulating liquid is being saturated with gases and moisture. Sudden changes in temperature and atmospheric pressure can cause small bubbles to appear in the oil, which, under the influence of oil flow and electromagnetic fields, concentrate in the paper insulation, making it even more vulnerable.