PROBLEMS IN SLUDGE AND FUEL OIL

OIL SLUDGE ? The term oil sludge is often somewhat loosely used to denote all the material, which may settle out as bottom settlings when a tank of crude oil stands stagnant for some time. In your storage tank you have two materials to contact, water and particles of solid chemical compounds, commonly called sludge. This is collectively referred to as Bottom Sediment and Water (BSW) which varies greatly in amount and composition. Sludge is an oxidized product, or chemical compounds resulting from the oxidation of the hydrocarbons in the oil, forming insoluble materials, mostly organic in nature, such as dirt, grit, tank rust-scale and similar material. The term sludge is used quite loosely and is generally understood to mean a combination of BSW and sludge.

Swelling Fuel Oil Problems

HANDLING OF SLUDGE

One of the main reasons why there is a build-up of sediment and sludge in many storage tanks is that it is permitted to settle and accumulate. If the bottom of the suction and return lines is too high in the tank, most of the oil below the lines remains stationary, resulting in an accumulation of sludge due to undisturbed settling. Also in some installations portions of the oil in the tank are never activated, the fill line is at one end of the tank and the suction line is in the middle, leaving the other end practically undisturbed for long periods of time.

This permits the sediment to accumulate instead of being kept in suspension by circulation of excess oil returning from the burners as well as when fresh oil is received. When there is a large amount of sediment on the bottom, one or other problem arises. When a load of oil is pumped into a storage tank, it causes the oil and sludge present to become agitated and leaves the sediments in suspension. This mixture is then pulled through the lines, blocking strainers and either cutting off the burner completely causing erratic combustion.

Also if the waxy sludge deposit is allowed to build up to any great extent it becomes thicker and more compacted and much more difficult to remove. This eventually necessitates the opening of a side door of the tank and manually digging several feet of sludge, with its attendant problems such as disposal as discussed earlier.

SYMPTOMS OF SLUDGE FORMATION

Fouling of suction heaters, Frequent chocking and cleaning of pre-heaters, filters, strainers, burners, nozzles, Fall in temperature at burners, Increase in pumping pressures, Algae formation at the tanks bottom etc.

SOOT, ASH AND DEPOSITS

Soot is formed as a result of poor combustion, in powdery form of carbon and combustible with sufficient air. The impurities or foreign materials are noticeable. These organic and inorganic substances are non-combustible and after the combustion of fuel oil residue is called ash.

CORROSION DUE TO SLUDGE

Sediment and sludge are formed in oil tanks and fuel lines due to water separation from the fuel oil and when asphaltenes, waxes and other materials flocculate (stick together) and ultimately settle to the bottom. A certain amount of water is always found in fuel oil and additional water can come from condensation in the storage tank and during tank filling. The water normally separates out and remains at the bottom of the fuel tank in direct contact with the metal surface, leading to corrosion and E-OIL prevents corrosion.

ALGAE FORMATION

Under the right conditions, micro-organisms can grow at the water/oil interface and contribute to an increase in the amount of sediment in the tank. The by-products of the micro- biological degradation cause corrosion of metal surfaces and E-OIL prevents Algae formation.

EMISSIONS AND HARMFUL POLLUTANTS

One of the critical problem caused by the sulfur contained in fuel oils is the lowering of the ambient air quality by pollution. The combustion converts sulfur to sulfur dioxide (SO2) a stringent, irritation gas, which is emitted from the smoke stack, contaminating the atmosphere. Harmful pollutants are SO2, CO, HC, Nox and SPM.