HU205621B - Process for producing additives of heat- and electrolite-resistant flushing liquides - Google Patents

Abstract

Heat and electrolyte resisting flushing fluids contain alkali-or alkali-earth humates. Humates are dispersed in water. Based on humate concns. - 0.05-0.6 pts.wt. sodium sulphite or potassium-meta-bisulphite and 0.02-0.6 pts wt of 36 wt% formaldehyde soln is added. This reaction mix is heat treated at 370-490 deg.C for 1-10 hrs, pref under agitation.

Description

The present invention relates to a process for the production of additives for alkali or alkaline earth humate based heat and electrolyte tolerant rinsing liquids.

A number of organic materials are used to control the rheological and filtration characteristics of aqueous rinsing fluids for hydrocarbon, ore, and water exploration and exploration wells. For example, tannic acid, lignosulfonates, low molecular weight polyacrylic acid, sulfonated styrene / maleic acid copolymer (Gray-DarleyRogers: Properties and composition of drilling fluids, Gulf Publishing Co., New York 1980) are used to reduce viscosity.

Starch and derivatives thereof, carboxymethylcellulose (CMC), hydroxyethylcellulose (HEC), high molecular weight polyacrylic acid, vinyl sulfonate / vinylpyrrolidone copolymer, etc., are used to control filtration characteristics. are used.

Particularly in deep, high temperature (above 300-320 K) boreholes, the thermal stability of the additives used becomes extremely important, which means that they can perform their function permanently at high temperatures.

In addition to synthetic polymers, it is primarily the humic acid derivatives which have excellent thermal stability and are capable of controlling both viscosity and water leaching (filtration).

A major disadvantage of the various alkali metal humates and their heavy metal (chromium-aluminum, iron, etc.) complexes is that their effect is critically reduced in media containing polyvalent ions (e.g., calcium, magnesium, etc.). The main reason for this is that the water solubility of the humates is essentially provided by the otherwise electrolyte sensitive carboxyl groups. The Hungarian patent number 174954 is intended to solve the above problem. It is well known that by sulfomethylation of humic acid and alkali metal humates, the electrolyte tolerance can be greatly improved, and even this product has been shown to be particularly effective in systems containing 500-2000 ntg / dm ³ Ca ⁺⁺ (Dormán J .: and experience in the use of electrolyte-tolerant additives (Petroleum and Natural Gas, September 1985). Owing to this recognition, further laboratory studies have shown that the viscosity-lowering effect of humates and their derivatives is generally greater when the average molecular weight is reduced. In this saint, the effect of regulating water release (filtration) usually increases with increasing molecular weight.

It has also been found in the course of our further work that heating of the hygrates at high temperature (370-511 K) in aqueous solution results in an increase in both the viscosity and water release control. This major change of practical importance is due to the fact that the temperature causes the chemical bonds of the human macromolecule to break relatively weak, the molecular weight is lowered and thus the viscosity-decreasing character is enhanced, the increase in the adsorptive property improves the filtration characteristics (water release).

The process according to the invention consists in dissolving or dispersing humic acid or the alkaline earth metal humate in water and then heating it at 370-490 K for 1-10 hours, and simultaneously or subsequently sulfomethylating it with a mixture of aldehyde and sulfite. with a reaction mixture containing 0.05 to 0.6 parts by weight of sodium sulfite or potassium metabisulphite and 0.02 to 0.6 parts by weight, preferably 0.1 to 0.4 parts by weight of formaldehyde per humate .

The following examples illustrate the process without limiting the scope of the invention.

Example 1

235 g of potassium humate were dispersed in 500 cm ^{3 of} water, 32 g of potassium metabisulphite and 30 cm ^{3 of a} 36% formaldehyde solution were added with stirring and heated at 450-455 K for 120 minutes (preferably with stirring). The resulting sulfomethylated and partially condensed humate (sample A) in the gypsum-based rinsing liquid has a greater reduction in water release than known domestic and foreign products (Table 1).

Example 2

235 g of potassium humate were dispersed in 500 cm ^{3 of} water, and 60 g of potassium metabisulphite and 30 cm ^{3 of} formaldehyde (36% solution) were added with stirring. The reaction mixture was heated at 450-455 K for 120 minutes (preferably with stirring). The resulting sulphomethylated and partially condensed humate (sample B) in the gypsum-based rinse liquid reduces the water release better than the known domestic and foreign product (Table 1).

The barite-weighted gypsum-based rinsing fluids with a density of 1650 kg / m ^{3 contained} 30 kg / m ³ of various additives. The doped samples were heat treated at 473 K for 24 hours in a rotating autoclave of "Barons" (USA). Table 1 shows the characteristics measured at 300 K after heat treatment and mixing.

/. spreadsheet

Additive thermo humex Resi- nex "THE" "B" Apparent viscosity mPa.s 30 50 40 42 Plastic viscosity mPa.s 25 30 30 28 Flow limit Pa 6.1 20.4 10.2 14.3 Motion resistance (ΙΟ ') Pa 14.3 22.9 19.4 18.3 water Drop cm ³ 24 12.5 9.0 8.5 PH 8.1 8.1 7.9 7.9

Comment:

Termohumex - made in Hungary (according to the Hungarian patent number 174 954),

Resinex - foreign product (mixture of sulfonated humate and sulfonated phenol / novolak resin).

It is apparent that the process of the present invention is derived2

The added additives reduce water release more effectively than the two products used and provide better rheological properties than Resinex.

Example 3

1200 g of potassium humate were dispersed in 3000 cm ^{3 of} water and divided into six 500 cm ³ portions, each containing 35 cm ^{3 of a} 36% solution of formaldehyde and 25, 50, 100 g of sodium sulphite (Ν _{3 2} δΟ ₃ ), or 25, 50, 100 g of potassium metabisulphite 10 were added and the reaction mixture was heated at 400 K for 240 minutes (preferably with stirring).

The results summarized in Table 2 show that the same basic fluid treated with 30 kg / m ^{3 of} the same basic liquid after 6 hours of heat treatment at 493 K, predominantly with 25 and 50 g of sodium sulphite (C and D) and potassium good results are obtained with substances treated with metabisulfite (F and G). Natural products made using 100 g of sodium sulphite (E) and potassium metabisulphite (H) are less effective.

Example 4

630 g of sodium humate were dispersed in 1500 cm ^{3 of} water and 75 g of potassium metabisulphite was added with stirring. The suspension was divided into 3 equal portions, to which 25, 50, and 75 cm ^{3 of} formaldehyde were added and heated at 400 K for 240 minutes. The efficacy of the "I", "J" and "K" additives thus obtained is shown in Table 3. It can be stated that each sample provides better drainage than the known products.

Example 5

850 g of potassium humate were dispersed in 2000 cm ^{3 of} water and 100 g of potassium metabisulphite and 100 cm ^{3 of} 36% formaldehyde solution were added with stirring. The reaction mixture was divided into four equal portions at 410 K for various times (preferably with stirring). The efficacy of the additives cured for 2, 3, 4, 6 hours (L, Μ, N, O) is shown in Table 4. All new products are more effective than known products.

Table 2

Water-reducing effect of sulfomethylated humate derivatives in gypsum-based rinsing liquid

Additive: c D E F G H Termohumex Resinex Apparent viscosity mPa.s 32.5 37 95 49 49 75 30 30 Plastic viscosity mPa.s 23 18 20 35 33 27 ' 20 13 Flow limit Pa 9.7 19.4 66.4 14.3 16.3 49.0 10.2 22.5 Motion resistance (10 ') Pa 11.1 25.5 38.3 16.8 20.4 50.1 17.9 26.1 water Drop 3 cnr 15 23 66.0 7.5 17 48 33 10 PH 8.63 9.04 9.41 8.63 8.40 8.27 8.96 8.99

Table 3

Effectiveness of sulfomethylated humates with various amounts of formaldehyde in gypsum-based rinsing fluid (heat treatment: 473 K - 6 hours)

Additive: J K Termohumex Resinex Apparent viscosity mPa.s 19 25 27 31 29 Plastic viscosity mPa.s 18 24 26 25th 24 Flow limit Pa 1.0 1.0 1.0 3.6 5.1 Motion resistance (10 ') Pa 1.5 2.0 2.5 7.7 4.6 water Drop cm ³ 6.0 5.2 5.1 17.5 9.5 PH 7.58 7.69 7.82 7.86 7.48

Table 4

Effectiveness of sulfomethylated humates in gypsum-based rinsing liquids heat treated for various periods of time (heat treatment 493 K - 6 hours)

Additive; L M N SHE Termohumex Resinex Apparent viscosity mPa.s 47.5 40 25 24 25 32.5 Plastic viscosity mPa.s 27 25 20 20 18 15 Flow limit Pa 20.9 15.5 5.1 4.1 7.1 17.9

HU 205 62 L B

Additive: L M N SHE Termohumex Resinex Motion resistance (10 ') Pa 5.1 5.1 2.0 1.5 5.1 16.8 water Drop cm ³ 8.3 8.3 8.1 8.0 27 17 PH 8.08 8.15 8.10 8.12 8.48 8.64

The tables show that the additives produced by sulfomethylation in the temperature and reaction time ranges of the present invention have a low association tendency and therefore have a greater viscosity viscosity in the rinsing fluids than the prior art additives. At higher reaction temperatures, the chemical structure of the human starting materials is changed and new functional groups are released for sulfomethylation, the initially poorly water-soluble components are revealed, and as a result, the active ingredient content increases.

However, at too high a temperature and / or for too long a reaction time, the structural degradation of the humates would be excessive and the additives produced would be less effective.

Claims (1)

A process for the preparation of additives for heat and electrolyte-tolerant rinsing liquids by sulfomethylation of water-dispersed alkali metal or alkaline earth metal humates with sodium sulfite or potassium metabisulfite and formaldehyde, characterized in that the sulfomethylation is carried out for while stirring.