CN104058526A - Flushing fluid purification treatment process - Google Patents

Abstract

The invention provides a flushing fluid purification treatment process. The flushing fluid purification treatment process includes the steps that waste water is drained from a well head and firstly enters a sand setting oil separator, so that oil slick and sand are preliminarily removed; sewage drained from the sand setting oil separator is pumped into a cyclone separator, sand and oil dirt are further separated, sewage drained from the cyclone separator is pumped into a buffer tank, substances with opposite charges are added, and then intermediate water is well purified; intermediate water directly enters a filter for filtration; filtered water enters a purification tank for standby; residual well flushing sand cleaning fluid is reinjected or brought back to a working site to continue to be used; solid-liquid separation is conducted on oil dirt and sand, and sand is made into cakes. The flushing fluid purification treatment process has the advantages that the quality of treated water can reach an oil well reinjection water standard, well flushing quality and efficiency are improved, and transport cost is saved.

Description

Flushing fluid purification process technique

Technical field

The present invention relates to a kind of sewage treatment process, especially a kind of oil field flushing liquor treating process.

Background technology

When Oil/gas Well clean-out service, with swiftly flowing liquid, silt is stopped up in shaft bottom and break up, and use the carrying capacity of returning in the circulation of liquid stream, the foundry loam sand breaking up is taken out of to ground and effectively prevented silt blocking hydrocarbon zone, guarantee Oil/gas Well stable yields.

When clean-out service return the husky oil-containing of well liquid band, turbidity is very high, the each well difference of duration of well flushing, several hours at least, more than ten hour at most.Because the each well in oil field disperses, often wash a bite well and must organize many tank cars to draw in clean water, pull out and return well liquid.Sometimes because waterhead area is far away, can affect the continuity of clean-out service.

Existing oil field flushing liquor treating process adopts special well-washing truck, its process using cyclonic separator desanding, again with after strainer oil removal for circulation well cleanup water, water quality can not reach oil field working fluid technological standard.

Summary of the invention

The object of the invention is to avoid prior art and a kind of flushing fluid purification process technique is provided.

Technical scheme of the present invention is: flushing fluid purification process technique, comprise sand setting, micro-electrolysis, dissolved air flotation, frizing, filtering separation, and concrete steps are:

1) first waste water enter sand setting oil trap oil slick and sand grains carried out to preliminary Transformatin from well head is discharged; Sand setting oil trap adopts highly different baffle combination, realizes sand setting step by step, and utilizes profit density difference, and most of oil slick is scraped in sand setting oil trap;

2) pump into cyclone separator from sand setting oil trap sewage out, further separate sand grains and greasy dirt, pump inlet fills 40～80 object filter screens, controls the sand grains particle diameter that enters treatment unit, reduces sand content in water;

3) pump into surge tank from cyclone separator sewage out, add with opposite charges material, make solubilized suspended substance class material in flushing fluid lose relative stability, make its mutual collision and fusion through stirring, reach coagulation, flco increase, the direct bridging of solubilized suspended substance class material in liquid, part silt particle sinks, flco floats to water surface by suspension, and middle water body is purified preferably;

4) in the middle of, water body directly enters strainer filtration;

5) the profit liquid that most silts are removed in step 3) middle and upper part pumps into flotation cell, bottom spirt pressurized air, by the dissolving nozzle in air supporting sedimenting system, Xiang Shuizhong carries a large amount of micro-bubbles, water-insoluble small oil droplet is attached on micro-bubble, increase the buoyancy of small oil droplet, it is floated rapidly, thereby make oil in water emulsion in liquid and the major part of dispersed oil become oil slick, trapped removal by the floating oil collecting device arranging in gas-floating chamber again, bottom water body enters strainer and filters; The frizing blade at flotation cell top scrapes off the oil on liquid level and impurity, finally scrapes into sump;

6) water after filtration enters purification water pool, stand-by; Remain well-flushing sand cleaning fluid re-injection or take back operation field and continue to use; Sump oil silt particle is carried out solid-liquid separation, makes silt particle and becomes cake.

Compared with prior art, advantage of the present invention is: water quality after treatment can reach oil field reinjection water standard, has not only improved well-flushing quality and efficiency, and saves roping cost.

Brief description of the drawings

Fig. 1 is process flow sheet of the present invention.

In figure: 1, sand setting oil trap, 2 is cyclone separator, and 3 is surge tank, and 4 is flotation cell, and 5 is strainer, 6 is purification water pool.

Embodiment

Describe embodiments of the invention in detail below in conjunction with accompanying drawing.

Flushing fluid purification process technique, comprises sand setting, micro-electrolysis, dissolved air flotation, frizing, filtering separation, and concrete steps are:

1) first waste water enter sand setting oil trap 1 oil slick and sand grains carried out to preliminary Transformatin from well head is discharged; Sand setting oil trap 1 adopts highly different baffle combination, realizes sand setting step by step, and utilizes profit density difference, and most of oil slick is scraped in sand setting oil trap 1;

2) pump into cyclone separator 2 from sand setting oil trap 1 sewage out, further separate sand grains and greasy dirt, pump inlet fills 40～80 object filter screens, controls the sand grains particle diameter that enters treatment unit, reduces sand content in water;

3) pump into surge tank 3 from cyclone separator 2 sewage out, add with opposite charges material, make solubilized suspended substance class material in flushing fluid lose relative stability, make its mutual collision and fusion through stirring, reach coagulation, flco increase, the direct bridging of solubilized suspended substance class material in liquid, part silt particle sinks, flco floats to water surface by suspension, and middle water body is purified preferably;

4) in the middle of, water body directly enters strainer 5 and filters;

5) the profit liquid that most silts are removed in step 3) middle and upper part pumps into flotation cell 4, bottom spirt pressurized air, by the dissolving nozzle in air supporting sedimenting system, Xiang Shuizhong carries a large amount of micro-bubbles, water-insoluble small oil droplet is attached on micro-bubble, increase the buoyancy of small oil droplet, it is floated rapidly, thereby make oil in water emulsion in liquid and the major part of dispersed oil become oil slick, trapped removal by the floating oil collecting device arranging in gas-floating chamber again, bottom water body enters strainer 5 and filters; The frizing blade at flotation cell top scrapes off the oil on liquid level and impurity, finally scrapes into sump;

6) water after filtration enters purification water pool 6, stand-by; Remain well-flushing sand cleaning fluid re-injection or take back operation field and continue to use; Sump oil silt particle is carried out solid-liquid separation, makes silt particle and becomes cake.

The present invention is directed to flushing fluid containing abrasive band oil, feature that turbidity is higher, the purification process technique that adopts chemical method and Physical to combine.By adding quantitative flotation agent, according to " coalescence " theory, mainly to use with the group of positive electricity (bearing) property to neutralize in some water and be electrically difficult to some particles that separate or make particle reduce its electromotive force with negative (just), it is played pendulum, and utilize its aggregation property that these particles are concentrated, and separate by method for floating.

Flotation process is mainly divided into 2 types according to the mode and the Air Bubble Size that form bubble in water, i.e. vane type By Bubble-floating Method and injection type gas floating method.The synergistic effect of its two kinds of methods improves decontamination effect improving.

1) vane type By Bubble-floating Method: turbine air flotation method is to rely on the impeller of high speed rotating to produce small bubble.Bubble is formed to returning in well liquid by mechanically mixing, and the residence time is short, and oil removal rate is high, and cost is low, adapts to the variation of water oleaginousness.

2) jet flotation process: jet flotation process is to utilize the principle of squirt pump, adopts and returns well liquid for spraying fluid, in the time that water sprays at a high speed from nozzle, suction chamber at nozzle forms negative pressure, gas is inhaled people's suction chamber, and when water passes through mixing section at a high speed, the gas carrying is sheared into micro bubble; At flotation cell, bubble floating, and be attached on oil droplet and solid particulate, bring it into the water surface.

Flushing fluid processing operation testing data sees the following form

Water quality detection reports the result 1

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Water quality detection reports the result 2

Claims (1)

1. flushing fluid purification process technique, comprises sand setting, micro-electrolysis, dissolved air flotation, frizing, filtering separation, it is characterized in that concrete steps are:

1) first waste water enter sand setting oil trap oil slick and sand grains carried out to preliminary Transformatin from well head is discharged; Sand setting oil trap adopts highly different baffle combination, realizes sand setting step by step, and utilizes profit density difference, and most of oil slick is scraped in sand setting oil trap;

2) pump into cyclone separator from sand setting oil trap sewage out, further separate sand grains and greasy dirt, pump inlet fills 40～80 object filter screens, controls the sand grains particle diameter that enters treatment unit, reduces sand content in water;

3) pump into surge tank from cyclone separator sewage out, add with opposite charges material, make solubilized suspended substance class material in flushing fluid lose relative stability, make its mutual collision and fusion through stirring, reach coagulation, flco increase, the direct bridging of solubilized suspended substance class material in liquid, part silt particle sinks, flco floats to water surface by suspension, and middle water body is purified preferably;

4) in the middle of, water body directly enters strainer filtration;

5) the profit liquid that most silts are removed in step 3) middle and upper part pumps into flotation cell, bottom spirt pressurized air, by the dissolving nozzle in air supporting sedimenting system, Xiang Shuizhong carries a large amount of micro-bubbles, water-insoluble small oil droplet is attached on micro-bubble, increase the buoyancy of small oil droplet, it is floated rapidly, thereby make oil in water emulsion in liquid and the major part of dispersed oil become oil slick, trapped removal by the floating oil collecting device arranging in gas-floating chamber again, bottom water body enters strainer and filters; The frizing blade at flotation cell top scrapes off the oil on liquid level and impurity, finally scrapes into sump;

6) water after filtration enters purification water pool, stand-by; Remain well-flushing sand cleaning fluid re-injection or take back operation field and continue to use; Sump oil silt particle is carried out solid-liquid separation, makes silt particle and becomes cake.