CN102978624A - Oil-gas field gas transmission pipeline corrosion inhibitor and preparation method thereof - Google Patents

Abstract

The invention discloses an oil-gas field gas transmission pipeline corrosion inhibitor and a preparation method thereof. The corrosion inhibitor provided by the invention is obtained by compounding polyether amine, diglycolamine and hexahydro-1,3,5-tris(hydroxyethyl)-s-triazine, wherein the three materials act synergistically so that the metal corrosion rate is greatly delayed. The oil-gas field gas transmission pipeline corrosion inhibitor is excellent, has the corrosion inhibition rate which can be up to 92%, and further has the advantages of simplicity in preparation, convenience in application and the like. The corrosion inhibitor can be applied to an oil-gas field system of gathering and transportation, and storage and transportation containing acidic and highly acidic gases, thereby reducing the corrosion rate of the corrosive gases to metals. The corrosion inhibitor has high volatility and thud is also capable of effectively protecting the top of an oil-gas field gas transmission pipeline; and an economic efficient ideal protection way is provided for the oil-gas field gas transmission pipeline.

Description

Oil-gas field gas transmission pipeline inhibiter and preparation method thereof

Technical field

The present invention relates to a kind of oil-gas field gas transmission pipeline inhibiter and preparation method thereof, 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

For the long moisture pipeline of heavy caliber, greater than DN400, the length moisture pipeline greater than 10km, the protection effect of existing inhibiter spraying is difficult to reach the pipeline top, in case condensation water appears in the pipeline top, causes especially easily corrosion such as bore.This phenomenon is found early than nineteen sixty; certain oil company of France carried out safety inspection to the gas transmission line of a long-term servicing fluids phase corrosion inhibitor protection at that time; find that heavy corrosion has occured pipeline top, many places; the corrosion rate at wedgelike point corrosion pit place is up to 5mm/a; and duct bottom is owing to there being the inhibiter protection, almost without corrosion.After this, the phenomenon of the easier heavy corrosion in moisture pipeline top is also found in other countries and area successively.

For the phenomenon of the easier heavy corrosion in above-mentioned moisture pipeline top, present main treating method is protected pipeline for regularly carrying out the pre-film of batch processing, but this treatment process can affect oil, the gas field produces.

The unfavorable meeting of corrosion prevention at moisture pipeline top has a strong impact on production and the delivery safety of gas.China city gas consumption rapid growth in recent years particularly, production and the gathering line of Sweet natural gas constantly extend, the production of pipeline construction and conveying environment be more sophisticated also, so also need more urgently a kind of means of alleviating simply, efficiently the pipeline top part corrosion.

Summary of the invention

The objective of the invention is gas transmission pipeline inhibiter that proposes a kind of brand-new prescription and preparation method thereof, this inhibiter can efficiently be protected the pipeline top, for gas transmission pipeline provides a kind of cost-effective desirable preventive means.

Except as otherwise noted, the per-cent that occurs herein is mass percent.

Main points of the present invention are: be vapour-phase inhibitor with polyetheramine, diglycolamine DGA, hydroxyethyl perhydro-s-triazine are composite, polyetheramine, diglycolamine, hydroxyethyl perhydro-s-triazine three synergy delay rate of metal corrosion greatly.

Oil-gas field gas transmission pipeline corrosion inhibitor formula of the present invention is as follows:

Polyetheramine 20～35%

Diglycolamine 30～40%

Hydroxyethyl perhydro-s-triazine 25～50%

This vapour-phase inhibitor high volatility has higher vapour pressure, is filled into rear any zone that can arrive by volatilizing in the pipeline in the pipeline, comprises the pipeline top, is applicable to contain CO ₂And H ₂The moisture transport pipeline top protection of S sour gas.Simultaneously; each component all has good water-soluble in the inhibiter of the present invention; dissolve in the condensation water of tube wall; in water; nitrogenous polar group in the component and the absorption of tube wall metallic surface electric charge; form the unit molecule rete in whole negative electrode and positive electrode zone, i.e. tube wall protective membrane, thus reach the purpose of effectively slowing down the pipeline top part corrosion.

Amine in the inhibiter of the present invention is effective pH value conditioning agent, can neutralize to be dissolved in volatile acid in the tube wall condensation water, effectively reduces CO ₂And H ₂The dividing potential drop of the sour gas such as S in steam reduces the meltage of sour gas in condensation water, improves the pH value of condensation water, thereby can obviously reduce corrosive pipeline speed.

The preparation method of oil-gas field gas transmission pipeline inhibiter of the present invention is:

Take by weighing in proportion polyetheramine, diglycolamine and hydroxyethyl perhydro-s-triazine, directly mix getting final product.This preparation method is simple, convenient, need not specific installation, and is with low cost.

The corrosion mitigating effect of oil-gas field gas transmission pipeline inhibiter of the present invention is excellent, and corrosion inhibition rate can reach 92%, has the advantages such as preparation is simple, application is convenient.Oil-gas field gas transmission pipeline inhibiter of the present invention can be used for containing the defeated and storing and transporting system of oil-gas field collection of acid and peracidity gas, reduces etchant gas to corrosion of metal speed.Because the strong volatility of inhibiter of the present invention, it can also protect oil-gas field gas transmission pipeline top efficiently, for the oil-gas field gas transmission pipeline provides a kind of cost-effective desirable preventive means.

Embodiment

Embodiment 1

The corrosion inhibitor formula of present embodiment is very content of quality such as prescription in the table 1(table):

Table 1 corrosion inhibitor formula

The test sequence number	Polyetheramine	Diglycolamine	The hydroxyethyl perhydro-s-triazine
				Prescription 1	20%	30%	50%
Prescription 2	20%	40%	40%
				Prescription 3	35%	30%	35%
Prescription 4	35%	40%	25%
				Prescription 5	33.3%	33.3%	33.4%

Take by weighing polyetheramine, diglycolamine and hydroxyethyl perhydro-s-triazine by proportioning shown in the table 1, directly mix and get final product through stirring.

Embodiment 2

Measure the slowly-releasing rate of prescription 1～5 inhibiter

According to the corrosion inhibition rate of JB-T7901-1999 " Uniform Corrosion Method of Laboratory Immersion Test method " measurement prescription 1～5 inhibiter, concrete steps are as follows:

(1) the test piece material is L245NS, it is of a size of 30mm * 15mm * 4mm(grows * wide * thick), test temperature is 100 ℃, test period is 72 hours.

(2) adopt acetone to clean test piece with wipe oil, through 120 before the test ^#The waterproof abrasive paper of granularity grinds, and cleans with dehydrated alcohol, and dehydrates, and dried test piece is weighed.

(3) Cl in the testing liquid ^-Content is 1.38 * 10 ⁵Mg/L, inhibiter content are 3000mL/L, and solvent is deoxidation distilled water.

(4) in testing liquid, pass into H ₂S and CO ₂Gas, H ₂S and CO ₂Gas pressure intensity is respectively 0.95MPa and 1.2Mpa.

(5) with in the test piece immersion test solution, under 100 ℃ test temperature, keep soaking 72 hours; Simultaneously do blank test to compare with the testing liquid that does not add inhibiter.

(6) take out test piece, then the corrosion product that adopts scrubbing powder, sour striping liquid cleaning test piece surface to produce adopts dehydrated alcohol to clean and drying, and dried test piece is weighed.

(7) calculate weightlessness according to the weight of test specimen in step (2) and (6), again according to following formula (1) and formula (2) Calculation of corrosion speed and slowly-releasing rate.

Adopt aforesaid method that 1～5 the inhibiter of filling a prescription is all done 3 groups of parallel tests, and Calculation of corrosion speed, get the corrosion inhibition rate of the mean value calculation inhibiter of erosion rate, the results are shown in Table 2～6.As can be seen from the table, prescription 1～5 inhibiter can significantly reduce erosion rate, all has excellent corrosion inhibition rate, and corrosion inhibition rate is 90.40% ~ 92.2%.

It is as follows that erosion rate is calculated formula:

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

In the formula:

V is erosion rate, unit: g/ (m ²﹒ h);

△ t is test period, unit: h;

△ m is the test piece corrosion weight loss, unit: g;

A is the test piece surface-area, unit: mm ²

The corrosion inhibition rate calculation formula is:

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

In the formula:

η is corrosion inhibition rate, unit: %;

ν ₀For not adding the erosion rate of inhibiter, unit: g/ (m ²﹒ h);

ν is the erosion rate that is added with inhibiter, unit: g/ (m ²﹒ h).

The slowly-releasing rate test result of the inhibiter of table 2 prescription 1

The slowly-releasing rate test result of the inhibiter of table 3 prescription 2

The slowly-releasing rate test result of the inhibiter of table 4 prescription 3

The slowly-releasing rate test result of the inhibiter of table 5 prescription 4

The slowly-releasing rate test result of the inhibiter of table 6 prescription 5

Claims (2)

1. oil-gas field gas transmission pipeline inhibiter is characterized in that its composition and mass percent are:

Polyetheramine 20～35%

Diglycolamine 30～40%

Hydroxyethyl perhydro-s-triazine 25～50%.

2. the preparation method of oil-gas field gas transmission pipeline inhibiter as claimed in claim 1 is characterized in that:

Take by weighing polyetheramine, diglycolamine and hydroxyethyl perhydro-s-triazine by proportioning, get final product through mixing.