A kind of in-situ cross-linked bio-based jelly for fracturing or profile control and its preparation method and application

Abstract

The invention discloses an in-situ cross-linked bio-based jelly for fracturing or profile control, a preparation method and application thereof. The bio-based jelly is formed by in-situ cross-linking of microbial fermentation broth containing biopolymers and a coordination cross-linking agent, wherein the amount of the coordination cross-linking agent used is 0.1-0.5 wt of the total mass of the fermentation broth %, the concentration of the biopolymer in the fermentation broth is 2-3 g / L. The bio-based jelly of the present invention uses non-toxic and environmentally friendly biopolymer fermentation liquid as raw material, omits the biopolymer extraction process, can avoid the cost caused by polymer extraction, and uses different types of coordination crosslinking agents , in-situ cross-linking to prepare bio-based jelly for different purposes, which can be widely used in conventional oil and gas reservoirs, reservoir stimulation operations of low-porosity tight oil and gas reservoirs and profile control of high-temperature, medium-high-temperature oil and gas reservoirs.

Description

technical field

[0001] The invention relates to a preparation method of in-situ cross-linked bio-based jelly for fracturing or profile control and its application in reservoir reconstruction and recovery improvement measures in the field of oil and gas development. Background technique

[0002] Biopolymers are polysaccharides metabolized by microorganisms under specific conditions. In oil extraction, biopolymers can be used as profile control agents and become an important means to enhance recovery and economic benefits. At present, it has been applied on a certain scale in petrochemical fields such as tertiary oil recovery, and the biopolymers with certain temperature and salt resistance properties mainly include the following categories: ① Guar gum is a neutral polysaccharide with excellent inorganic Salt compatibility, guar gum and its derivatives have become the most commonly used water-based fracturing fluid thickeners; ② Welan gum, a new type of high-viscosity water-s...

Examples

Embodiment 1

[0030] The sphingomonas single bacterium colony that produces guar gum preserved on the plate is inoculated in the seed culture medium (glucose 10g / L, NH 4 NO 3 0.5g / L, KH 2 PO 4 0.5g / L, MgSO 4 0.5g / L, yeast powder 2g / L, peptone 5g / L, pH 7.0~8.0), shake culture at 35°C and 150rpm for 1d to become seed liquid, and the seed liquid was added to the fermentation medium according to the volume ratio of 1:50 ( Glucose 10g / L, sucrose 1g / L, yeast powder 0.5g / L, urea 1g / L, K 2 HPO 4 0.5g / L, MgSO 4 0.2g / L, pH 7.0-8.0), shake culture at 35°C and 150rpm for 3 days to obtain a fermentation broth, and use a rotational viscometer to measure the viscosity of the fermentation broth to be 5060mPa·s. The above-mentioned fermented liquid was diluted 5 times, the viscosity was 246mPa·s, and the concentration of guar gum in the fermented liquid was 2.1g / L, which was used as the biopolymer base liquid for preparing the bio-based jelly.

Embodiment 2

[0032] The Alcaligenes single bacterium colony of producing Velan gum preserved on the plate is inoculated in the seed culture medium (glucose 10g / L, NH 4 NO 3 0.5g / L, KH 2 PO 4 1g / L, MgSO 4 0.5g / L, yeast powder 2g / L, peptone 10g / L, pH 7.0-8.0), shake culture at 35°C and 120rpm for 1d to become seed liquid, and the seed liquid was added to the fermentation medium according to the volume ratio of 1:50 ( Glucose 12g / L, sucrose 2g / L, yeast powder 1g / L, urea 2g / L, K 2 HPO 4 1g / L, MgSO 4 0.1g / L, pH 7.0-8.0), and vibrated at 35°C and 150rpm for 3 days to obtain a fermentation broth. The viscosity of the fermentation broth was measured to be 5230mPa·s using a rotational viscometer. The above fermentation broth was diluted 5 times, the viscosity was 269mPa·s, and the Welan gum concentration in the fermentation broth was 2.7g / L, which was used as the biopolymer base liquid for preparing bio-based jelly.

Embodiment 3

[0034] The Xanthomonas campestris single bacterium colony of producing xanthan gum preserved on the plate is inoculated in the seed culture medium (glucose 15g / L, NH 4 NO 3 1g / L, KH 2 PO 4 0.5g / L, MgSO 4 0.2g / L, yeast powder 5g / L, peptone 5g / L, pH 7.0~8.0), shake culture at 37°C and 180rpm for 2 days to become seed liquid, and the seed liquid was added to the fermentation medium at a volume ratio of 1:20 ( Glucose 15g / L, sucrose 1g / L, yeast powder 0.5g / L, urea 1.5g / L, K 2 HPO 4 0.5g / L, MgSO 4 0.2g / L, pH7.0~8.0. ), vibrated at 37° C. and 150 rpm for 5 days to obtain a fermentation broth, and the viscosity of the fermentation broth was measured to be 5150 mPa·s using a rotational viscometer. The above fermentation broth was diluted 5 times, the concentration of xanthan gum in the fermentation broth was 2.3g / L, and the viscosity was 253mPa·s, which was used as the biopolymer base liquid for preparing bio-based jelly.

technical field

[0001] The invention relates to a preparation method of in-situ cross-linked bio-based jelly for fracturing or profile control and its application in reservoir reconstruction and recovery improvement measures in the field of oil and gas development. Background technique

[0002] Biopolymers are polysaccharides metabolized by microorganisms under specific conditions. In oil extraction, biopolymers can be used as profile control agents and become an important means to enhance recovery and economic benefits. At present, it has been applied on a certain scale in petrochemical fields such as tertiary oil recovery, and the biopolymers with certain temperature and salt resistance properties mainly include the following categories: ① Guar gum is a neutral polysaccharide with excellent inorganic Salt compatibility, guar gum and its derivatives have become the most commonly used water-based fracturing fluid thickeners; ② Welan gum, a new type of high-viscosity water-s...

Examples

Embodiment 1

[0030] The sphingomonas single bacterium colony that produces guar gum preserved on the plate is inoculated in the seed culture medium (glucose 10g / L, NH 4 NO 3 0.5g / L, KH 2 PO 4 0.5g / L, MgSO 4 0.5g / L, yeast powder 2g / L, peptone 5g / L, pH 7.0~8.0), shake culture at 35°C and 150rpm for 1d to become seed liquid, and the seed liquid was added to the fermentation medium according to the volume ratio of 1:50 ( Glucose 10g / L, sucrose 1g / L, yeast powder 0.5g / L, urea 1g / L, K 2 HPO 4 0.5g / L, MgSO 4 0.2g / L, pH 7.0-8.0), shake culture at 35°C and 150rpm for 3 days to obtain a fermentation broth, and use a rotational viscometer to measure the viscosity of the fermentation broth to be 5060mPa·s. The above-mentioned fermented liquid was diluted 5 times, the viscosity was 246mPa·s, and the concentration of guar gum in the fermented liquid was 2.1g / L, which was used as the biopolymer base liquid for preparing the bio-based jelly.

Embodiment 2

[0032] The Alcaligenes single bacterium colony of producing Velan gum preserved on the plate is inoculated in the seed culture medium (glucose 10g / L, NH 4 NO 3 0.5g / L, KH 2 PO 4 1g / L, MgSO 4 0.5g / L, yeast powder 2g / L, peptone 10g / L, pH 7.0-8.0), shake culture at 35°C and 120rpm for 1d to become seed liquid, and the seed liquid was added to the fermentation medium according to the volume ratio of 1:50 ( Glucose 12g / L, sucrose 2g / L, yeast powder 1g / L, urea 2g / L, K 2 HPO 4 1g / L, MgSO 4 0.1g / L, pH 7.0-8.0), and vibrated at 35°C and 150rpm for 3 days to obtain a fermentation broth. The viscosity of the fermentation broth was measured to be 5230mPa·s using a rotational viscometer. The above fermentation broth was diluted 5 times, the viscosity was 269mPa·s, and the Welan gum concentration in the fermentation broth was 2.7g / L, which was used as the biopolymer base liquid for preparing bio-based jelly.

Embodiment 3

[0034] The Xanthomonas campestris single bacterium colony of producing xanthan gum preserved on the plate is inoculated in the seed culture medium (glucose 15g / L, NH 4 NO 3 1g / L, KH 2 PO 4 0.5g / L, MgSO 4 0.2g / L, yeast powder 5g / L, peptone 5g / L, pH 7.0~8.0), shake culture at 37°C and 180rpm for 2 days to become seed liquid, and the seed liquid was added to the fermentation medium at a volume ratio of 1:20 ( Glucose 15g / L, sucrose 1g / L, yeast powder 0.5g / L, urea 1.5g / L, K 2 HPO 4 0.5g / L, MgSO 4 0.2g / L, pH7.0~8.0. ), vibrated at 37° C. and 150 rpm for 5 days to obtain a fermentation broth, and the viscosity of the fermentation broth was measured to be 5150 mPa·s using a rotational viscometer. The above fermentation broth was diluted 5 times, the concentration of xanthan gum in the fermentation broth was 2.3g / L, and the viscosity was 253mPa·s, which was used as the biopolymer base liquid for preparing bio-based jelly.

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