CN102660244A - Composite-type oil-gas field corrosion inhibitor - Google Patents

Abstract

The invention relates to a high-efficient composite-type corrosion inhibitor for corrosion resistance of an acid-gas oil-gas field metal material containing carbon dioxide (CO2) and hydrogen sulfide (H2S) and a preparation method thereof. Tall-acid dicyclohexyl amide and triphenylamine oleic acid salt are compounded into a compound, so that the metal corrosion speed can be greatly slowed down under the synergistic action of the tall-acid dicyclohexyl amide and the triphenylamine oleic acid salt. A high-efficient inhibitor is obtained by mixing the following ingredients by weight percent: 15 to 20 percent of the compound, 1 to 3 percent of non-ion surface active agent, 10 to 15 percent of ethylene glycol, 5 to 10 percent of propargyl alcohol and 1 percent of citric acid and balance of water. The composite inhibitor has good solubility and oil dispersion property, the production process is simple, and no environment pollution occurs. The inhibitor has excellent slow-release effect in a corrosion environment and can be used in an acid oil-gas field ground gathering and storage transportation system to prevent the damage of metal materials caused by corrosive gases and to reduce the corrosion loss.

Description

A kind of compound fld inhibiter

Technical field

The present invention relates to a kind of fld inhibiter, be mainly used in oil, gas well production, the anti-corrosion of metal in the pipeline transportation process belongs to field of fine chemical.

Background technology

The continuous development of oil-gas exploration industry is drilled deep formation and is contained H ₂S, CO ₂, salt solution and composition thereof the stratum increase H gradually ₂S and CO ₂Gas can cause down-hole oil production, the pitting corrosion of gas equipment or fracture, can not solve the equipment corrosion problem with conventional drilling method and anti-corrosion measure.In medium, add a small amount of inhibiter of people, can significantly reduce Corrosion of Metallic Materials speed, and can keep the physical and mechanical properties of metal constant.Inhibiter has that cost is low, simple to operate, instant effect, can protect integral device, be fit to characteristics such as long-term protection, and the employing inhibiter is undoubtedly one of optimized protection measure of fld equipment.

Traditional fld inhibiter is the organic cpds of non-environment-friendly type, and part also has severe toxicity, such as pyrimidine and shin class etc.As China's oil enterprise improves constantly enterprise-quality, safety, environmental management requirement, is eliminated in succession.

The more inhibiter of present domestic use basically all is an adsorption corrosion inhibitor, like tetrahydroglyoxaline, quaternary ammonium salt and acid amides etc., generally believes that these inhibiter have corrosion inhibition preferably.But tetrahydroglyoxaline and amides inhibiter are water-soluble relatively poor usually, are incompatible with the fld chemicaladditives, very easily produce deposited phenomenon, have a strong impact on the result of use of various medicaments.

Summary of the invention

Technical problem to be solved by this invention provides the good fld inhibiter of a kind of compatibleness.

Except as otherwise noted, the per-cent that occurs among this paper all is the quality percentage composition.

Main points of the present invention are: unite the host as inhibiter with appropriate youngster's acid two Cyclohexamides and triphenylamine oleate.The concrete prescription of fld inhibiter of the present invention is:

Acyl group in appropriate youngster's acid two Cyclohexamides has increased amino cloud density; Phenyl ring in the triphenylamine oleate and amino conjugation have increased the cloud density of N atom, make that the unoccupied orbital on they and the iron atom forms co-ordination bond; Adsorbed close is on the surface of iron; The long-chain hydrophobic alkyl of the other end can effectively stop the admission velocity of water and etching reagent, and the two synergy delays rate of metal corrosion greatly.

The preparation method of appropriate youngster acid two Cyclohexamides in the above-mentioned prescription can for:

In the good there-necked flask of drying, add appropriate youngster's acid of 0.1mol and 0.15mol sulfur oxychloride, nitrogen protection, reflux half a hour in water-bath, reaction system keeps dry.After having the flue gas generation, do not add 0.12mol dicyclohexyl amine and 20ml pyridine, reflux 4 ~ 5 hours.With ice bath reactant is cooled off and stirring.Take out throw out, use a small amount of cold water flush, drying is utilized the pyridine dissolving to carry out recrystallization and is obtained white powder, is appropriate youngster's acid two Cyclohexamides.

The preparation method of the described triphenylamine oleate in the above-mentioned prescription can for:

Use mol ratio to add flask, fully stir down at 70 ℃ as oleic acid and the triphenylamine of 1:1, to dissolving fully, constant temperature 3 hours, cooling is after recrystallization obtains the triphenylamine oleate.

The preparation method of fld inhibiter of the present invention is: be dissolved in the water Hydrocerol A earlier, add hexylene glycol, propiolic alcohol and nonionogenic tenside more respectively, after fully stirring, add appropriate youngster's acid two Cyclohexamides and triphenylamine oleate, stirring gets final product.

Fld inhibiter of the present invention is used for fld and contains CO ₂And H ₂The oil well of S, gas well, and the ducted anti-corrosion of metal of surface gathering and transferring.

Inhibitor agent of the present invention is used for acid and peracidity fld collection is defeated and storing and transporting system.

Fld inhibiter of the present invention has good dispersiveness, reaches one-level with the compatibility of acid fluid system, and inhibition efficiency can reach 95%.Have advantages such as compatibleness is good, practicality is wide, in actual use, more can bring into play good corrosion prevention effect, also do not influence the use properties of other chemical agents simultaneously.

Embodiment

Embodiment 1

Inhibiter Example formulations such as following table (mass percent %):

Table one formula test

Recipe: be dissolved in the water Hydrocerol A earlier, add hexylene glycol, propiolic alcohol and nonionogenic tenside more respectively, fully stir, add appropriate youngster's acid two Cyclohexamides and triphenylamine oleate again, stirring at last gets final product.

Embodiment 2

Contact angle is measured

Contact angle is meant that the tangent line of the liquid-vapo(u)r interface of doing in gas, liquid, solid three joining places passes the angle between liquid and the solid-liquid boundary line, is measuring of wetness degree, is to weigh liquid combines tightness degree at solid surface important indicator.Utilize Kruss DSA20 type contact angle measurement to record the contact angle such as the table two of above-mentioned four kinds of corrosion inhibitor formulas and steel surface; This shows that there is good wellability on this inhibiter and steel surface; Contact closely can effectively stop corrosive fluid to contact with carbon steel, plays good corrosion inhibition.

Table two contact angle is measured

The test sequence number	Contact angle (degree)
		Prescription 1	15.5
Prescription 2	15.1
		Prescription 3	14.9
Prescription 4	15.4

Embodiment 3

Inhibition efficiency is measured

According to SY 5405-1996 " acidifying is with inhibiter method for testing performance and evaluation index ", specify the corrosion mitigating effect of novel corrosion inhibitor of the present invention through test simulation, see table three.Concrete steps:

(a) material for test is N-80, is of a size of 50 * 10 * 3mm.Test temperature is 140 ℃, and pressure is 16MPa, and test period is 4 hours.

(b) acid solution be hydrochloric be 15%, or mud acid is 15% solution (with reference to the table 3 among the SY 5405-1996 " acidifying is with inhibiter method for testing performance and evaluation index ").Add novel corrosion inhibitor in the instance 1 to acid solution, the inhibiter consumption is 2%～3% of an acid solution.

(c) test is preceding with 400 ^#Abrasive paper for metallograph is polished to light to test piece one by one, uses the acetone surface again, removes degreasing.

(d) after drying is weighed, soak 4 hours (doing blank simultaneously with the acid solution that does not add inhibiter) in the acid solution of test piece adding homothermic adding inhibiter, weigh again.

(e) calculate weightlessness, calculate erosion rate and corrosion rate by following formula (1) and formula (2).

Erosion rate is calculated formula:

$v=\frac{{10}^6\×\mathrm{\Δm}}{A\×\mathrm{\Δt}}---\left(1\right)$

In the formula: v ... Erosion rate, g/ (m ²H);

△ t ... Reaction times, h;

△ m ... The test piece corrosion weight loss, g;

A ... The test piece surface-area, mm ²

Corrosion inhibition rate calculation formula formula is:

$\mathrm{\η}=\frac{v_0-v}{v_0}---\left(2\right)$

In the formula: η ... Corrosion inhibition rate, %;

v ₀The erosion rate that does not add inhibiter, g/ (m ²H);

V ... Be added with the erosion rate of inhibiter, g/ (m ²H).

(f) concrete acid solution is formed and experimental data calculates inhibition speed and inhibition efficiency such as table three.

Table three corrosion efficient

Claims (2)

1. a fld inhibiter is characterized in that, its composition and mass percent are:

Appropriate youngster's acid two Cyclohexamide 5%-20%

Triphenylamine oleate 10%-30%

Nonionogenic tenside 1%-3%

Hexylene glycol 10%-15%

Propiolic alcohol 5%-10%

Hydrocerol A 1%-3%

Water surplus.

2. the preparation method of a fld inhibiter is characterized in that, is dissolved in the water Hydrocerol A earlier; Add hexylene glycol, propiolic alcohol and nonionogenic tenside more respectively; After fully stirring, add appropriate youngster's acid two Cyclohexamides and triphenylamine oleate, stir.