Solid corrosion inhibitor particle technology report

1.Background of Solid Corrosion Inhibitors

Adding corrosion inhibitors is an important measure to slow down metal corrosion in oil and gas fields. However, there are some shortcomings in the use of traditional corrosion inhibitors, so the development of new corrosion inhibitors has become inevitable.

Liquid corrosion inhibitors Solid corrosion inhibition rod Solid corrosion inhibitor granules

Disadvantages of liquid corrosion inhibitors:
a) The cost of dosing is high (frequent manual operations require dosing pumps, dosing tanks and other equipment).
b) The agent easily adheres to the inner wall of the oil pipe, causing greater loss.
c) The management of chemical dosing operations is difficult.
Disadvantages of solid corrosion inhibitor rods:
a) It needs to be placed in a customized pipe string, which is inconvenient to use.
b) The specific surface area is smaller than that of solid corrosion inhibitor particles, and the release rate decays quickly.
c) The wellbore is not straight, making it inconvenient to add.

2.Product brief introduction

(1) Advantages of solid corrosion inhibitor particles
a) No need for equipment such as dosing pumps and dosing tanks, reducing material consumption.
b) No need for manual supervision and maintenance of filling equipment, reducing labor costs.
C) Compared with liquid corrosion inhibitors, it is more convenient to transport and store.
d) The effective protection time of one dose is long.
e) The product uses a composite corrosion inhibition main agent, which can take into account the reduction of H₂S, CO₂ and salinity media.

(2) Technical indicators and their usage

Technical indicators

Item	Reference Range	Test Method
Appearance	Pale yellow to brownish-black solid particles	Visuals
Density(20℃,g/cm³)	1.10-1.40	GB/T4472
Particle Size ( mm )	2-7	The company’s enterprise standard
Usage Period (months)	3	The company’s enterprise standard
Corrosion Inhibition Rate(%)	≥70	SY/T 5273-2014

Method of Use：
①Applicable temperature: ≤70℃
②Working pressure: ≤25Mpa
③ This product is added directly through the oil casing. During the adding process, the agent is added to the bottom of the well with clean water; the accumulation height of the product at the bottom of the oil and gas well shall not exceed the perforation section.
④Dosage amount: Adding 40 kilograms of agent/liquid collection volume (cubic meter) to a single well can effectively protect for three months. For example, the average daily liquid production volume of a single well is 5 cubic meters, and adding 200 kilograms of chemicals can effectively protect it for three months.
⑤Dosing cycle: Add once every 3 months.

(3)Composition and proportion of each component

(4) On-site dosing method and its mechanism in the oil well system

On-site dosing method Mechanism of action

3.Performance evaluation

(1) Simulated water quality performance evaluation experiment
① Preparation of experimental media

Ions in simulated water	Cl-	SO₄2-	HCO₃	Mg²+、Ca2+	Na+、K+	Total Salinity
Ion concentration(mg/L)	29246.3	919.5	1214.4	230.6	19318.6	51817
remark	Jurassic water quality ion data of an oilfield in China

CO₂ gas cylinder gas cylinder control valve saturated CO₂ gas

Corrosive medium: Saturated carbon dioxide gas with the above simulated water quality for 1 hour.

② Experimental methods
Basis: SY/T 5273-2014 (Performance Index and Evaluation Method of Corrosion Inhibitor for Oilfield Produced Water Treatment)
Operation method: Take 500ml of the above experimental medium, add 1g of solid corrosion inhibitor, use N80 material for hanging sheets, temperature 60°C, test period 7 days.

③ Experimental results

The first day of the experiment The seventh day of the experiment

Experimental data

Specimen	Hanging sheet number	Pre-experimental quality/g	Post-experimental mass/g	Weightlessness/g	Average weight loss/g	Corrosion inhibition rate/%
Medication	701	11.1582	11.1478	0.0104	0.0108	77.3
	412	10.9261	10.9149	0.0112
Blank	423	10.5463	10.4983	0.0480	0.0476	/
	489	10.8915	10.8443	0.0472

Macroscopic picture after test strip processing

The apparent morphology of the specimen was observed after magnifying 50 times with a metallographic microscope

Microscopic picture of the surface of the new piece ：No412
Microscopic picture after blank specimen processing：No423
Microscopic picture after dosing specimen treatment：No412  

Test piece number: 412 Test piece number: 423 Test piece number: 412

(2) On-site water quality performance evaluation experiment

① Experimental medium

An oil field in China	Block	Pound Sign
Three oil production plants	Bei si zhuan	Liu34-51well
		Liu34-481well
	Bei wu zhuan	Liu13-33well
		Liu19-32well

② Experimental methods

Take the above-mentioned on-site water sample and fill it into a 500ml experimental bottle (the water sample must fill the experimental bottle to prevent oxygen from entering the bottle and interfering with the experimental results), add 1g of solid corrosion inhibitor particles, 1 piece of N80 steel, 60°C for 7 days, and conduct a blank experiment at the same time.

③Experimental results

Blank Medication

a: Liu34-51Well e: Liu34-51Well

b: Liu34-481Well f: Liu34-481Well

c: Liu13-33Well g: Liu13-33Well

d:  Liu19-32Well h: Liu19-32Well

Experimental data

Well No.	Sample	Specimen Number		post-experimental massg	Weightlessness/g
Liu34-51	Medication	427	10.9177	10.9169	0.0008	74.2
	Blank	449	11.0629	11.0598	0.0031	/
Liu13-33	Medication	440	11.1336	11.1328	0.0008	77.1
	Blank	480	11.0316	11.0281	0.0035	/
Liu19-32	Medication	707	11.0663	11.0656	0.0007	87.7
	Blank	447	11.0998	11.0941	0.0057	/
Liu34-581	Medication	219	11.0378	11.0366	0.0012	71.4
	Blank	408	11.0346	11.0304	0.0042	/

(3)Monitoring of the use of chemicals in the field

Monitoring method: Detect the total iron content of on-site produced water. Detection principle: Based on the o-phenanthroline iron measurement method, the iron measurement standard colorimetric tube (model: Fe-HX-10; manufacturer: Huaxing Chemical Reagent Factory) is used to detect the iron ion concentration of the on-site effluent.
Judgment basis：Total iron content without adding	Total iron content after dosing Total iron content after dosing	The product is qualified  The product is not qualified

Detecting instrument

Standard colorimetric tube box for Inside the standard colorimetric cell for iron determination iron determination

Monitoring data of chemical use in No.7 Oil Production Plant

On-site samples of Oil Production Plant 7 / On-site water quality Water samples after oil and water separation / pictures during the testing process of total iron

Iron tube