LT4354B - Method for the desulfurization of liquid fuel - Google Patents

Abstract

Invention presents liquid fuel desulphuration method, where there sulphurous liquid fuel is being emulsified with fine dispersion magnesium oxide and water. When such a suspension-emulsion burns, sulphur dioxide reacts to magnesium ion and non-volatile sulphur compound, a magnesium sulphate, is being formed, the one that gets into ashes.

Description

The closest approach is to the desulphurisation of sulfur fuel by passing S0 ₂ gas from combustion through an aqueous suspension of Ca (OH) ₂ or CaCO ₂ according to the reactions which result in hydrated calcium sulfite.

Ca (OH) ₂ + SO ₂ + O, 5H ₂ O - * - CaSO ₃ .O, 5H ₂ O + H ₂ 0 (1) or CaCO ₃ + SO ₂ + O, 5H ₂ O - CaSO ₃ .O, 5H ₂ O + C0 ₂ (2), which, in the presence of oxygen in further air oxidation, forms bipolar gypsum:

CaSO ₃ .0, 5H ₂ O + O, 5O ₂ + 1.5H ₂ O -> - CaSO _{4 4.} 2H ₂ O (3)

The disadvantage of technology is that all combustion products must be passed through gigantic absorbers with alkaline reagents and large amounts of water.

The object of the invention is to simplify the purification process by avoiding the formation of wastewater.

This problem is solved by the method of desulphurization of liquid fuels by the action of sulfur compounds' alkali introduced by emulsifying mixtures of liquid fuels and water prior to combustion which bind to volatile compounds upon heating. The alkali uses finely dispersed magnesium oxide in a ratio of sulfur (0.8-1.2): 1 and the aqueous suspension contains 10-35% by weight of the liquid fuel.

Advantages achieved include the avoidance of harmful substances S0 ₂ and the harmful effects on the environment. Throughout the process, chemical reactions are interconnected and complementary, resulting in an environmentally friendly technology as a whole.

The proposed production method is realized in two stages: according to the presented technological scheme, which contains ten operations.

In the first stage, any sulfuric liquid fuel is heated to a temperature of 70-90 C to reduce the viscosity. In parallel, a suspension is prepared from the finely dispersed magnesium oxide and warmed water at ~ 70 ° C, whereby partial magnesium oxide hydration occurs. The two warm components are directed to a dispersant (rotary-pulsator) to produce a suspension-emulsion of sulfur liquid fuel, magnesium oxide and water. Optimal dispersion phase sizes of suspension-emulsion particles range from $ 2.5.10 to 75.IO- ⁶ .

In the second stage, a slurry-emulsion of sulfur fuel oil, magnesium oxide and water, heated to a temperature of 7 to 9 ° C, is injected into a furnace using a pump and compressed air for combustion, whereby the following reaction occurs:

Mg (OH) ₂ + S0 ₂ + 0.5O ₂ Λ ^ΘΓηρ ·> MgSO ₄ + E ^ O (4)

According to the fourth reaction (4), sulfur liquid fuel sulfur does not escape through the stack with C0 ₂ gas and H ₂ 0 vapor into the atmosphere, but remains in the ash.

Example I.Liquid fuel (fuel oil) - containing 85 kg * o

2.4% sulfur, heated to 80 ° C. It is directed to the dispersant. In parallel, a suspension of 3 kg of magnesium oxide (ratio Mg: S = 1: 1) and 15 kg of water at 70 ° C, which is 15% by weight of the liquid fuel, is produced.

In the unit, the slurry is mixed with the liquid fuel until v -5 to disperse mass particle sizes of 2.5.10 to

75.IO- ⁶ yrs.

The prepared fuel is burned in the furnace. The other examples are analogous to the first example. The results are shown in the table.

As shown in the table, the optimum magnesium oxide and sulfur introduced into the slurry-emulsion thereof have a 1: 1 stoichiometric ratio and 15.0% water content with respect to the liquid fuel. Degree of purification of combustion gases from sulfur - 100% (Example I).

Increasing the amount of suspension-emulsion magnesium oxide is inappropriate because in this case unreacted magnesium oxide is found (Example 4).

Table

Pavyz- dys For despair used ratio, Mg: S Quantity of liquid fuel, % Water quantity, % Degree of purification of combustion gases from sulfur, % 1 1: 1 85.0 15.0 100.0 2 1.2: 1 85.0 ' 15.0 100.0 3 0.8: 1 85.0 15.0 80.0 4 1.3: 1 85.0 15.0 100.0 5 0.7: 1 85.0 15.0 70.0 6th 1: 1 85.0 15.0 100.0 7th 1: 1 65.0 35.0 100.0 8th 1: 1 90.0 10.0 100.0 9th 1: 1 62.0 38.0 100.0 10th 1: 1 92.0 8.0 62.0 11 (prototype) - - 90.00

By reducing the amount of suspension-emulsion magnesium oxide in Example 5), the degree of purification of the combustion gases from the sulfur is reduced to 70.0%.

The optimum water content of the suspension-emulsion with respect to the liquid fuel is 15.0%. the degree of desulphurisation of the exhaust gas is 100.0% at a torch temperature close to the combustion temperature of pure liquid fuel (Example 6).

Increasing the water content above 35.0% of the sulfur emissions does not change the degree of purification (Example 9), but the temperature of the torch drops by 15O - 20 ° C.

Reducing the water content below 10.0% complicates the homogeneous distribution of magnesium oxide in the suspension-emulsion, resulting in a reduction of the purification rate of the exhaust gas from sulfur to 62.0% (Example 10).

The proposed liquid fuel desulphurisation scheme can be easily used in production. Combustion gases emitted by power plants, boiler houses and other companies that use sulfur liquid fuels will not pollute the environment with sulfur dioxide.

Claims (3)

DEFINITION OF INVENTION 1.The desulphurisation process of liquid fuels, wherein the sulfur compounds released are treated with an aqueous suspension of alkali or carbonate, characterized in that the sulfur compounds in the liquid fuel are treated with alkali by emulsifying the liquid fuel and water mixtures prior to combustion which binds to volatile compounds. . 2. A process according to claim 1, wherein the alkali utilizes a fine dispersion of magnesium oxide with a sulfur ratio (0.8-1.2): 1. 3. A process according to claim 1, wherein the aqueous suspension comprises 10-35% by weight of the liquid fuel.