CN101798149B - Method for treating three-element composite-driven produced water - Google Patents

Abstract

The invention provides a method for treating three-element composite-driven produced water, which comprises the following steps: (1) testing the quality of the three-element composite-driven produced water, regulating the pH value to 9-12.5 by using a pH regulator, and adding 4000-11000 mg of treating agent into every 1L of the three-element composite-driven produced water, wherein the treating agent is one or the mixture of magnesium chloride, magnesium sulfate and magnesium nitrate in a random ratio; (2) while adding the treating agent, stirring the three-element composite-driven produced water at the stirring rate of 100-300 rpm for 2-15 minutes, and standing to settle for 10-30 minutes; and (3) and after filtering with quartz sand, carrying out the subsequent treatment. The invention has the advantage of favorable treatment effect and decreased treatment cost. The invention uses cheap and readily-accessible magnesium salts as the treating agent, requires simple treatment conditions, reduces the treatment cost, and can treat the three-element composite-driven produced water to reach the oil-field reinjection water standard.

Description

A kind of treatment process of ternary composite flooding water extraction

Technical field

The present invention relates to provide a kind of technology of handling ternary composite flooding water extraction, belong to technical field of sewage.

Background technology

China is one of shortage of water resources and the with serious pollution country of water, and the task of water treatment is more and more important.Along with each elephant of China gets into tertiary phase in succession, increasing Oilfield using tertiary oil recovery technology, wherein the ternary composite driving technology is very important a kind of mode of adopting of driving.The ternary composite driving The Application of Technology has improved oil recovery factor, has guaranteed the oil production amount; But inevitably brought serious negative effect; Ternary composite flooding water extraction contains crude oil, oil-displacing agent and suspended substance simultaneously, is a kind of reluctant high stable emulsification system of complicacy.Mostly the oil field existing treatment technology is " oil removal-filtration " or " oil removal-flotation-filtration " and " oil removal-flocculation-filtration " at present, but these traditional technologys can not be handled ternary composite flooding water extraction effectively.In addition, because the oil extraction-generated waste water complicated component, biodegradability is poor, has limited the use of biochemical processing; The popularization of membrane separation technique that oil removal efficiency has hanged down issues limit such as reaching the film pollution; Chemical agent is handled more effective, but general cost is higher, is inappropriate for large-scale application.Ternary composite flooding water extraction must pass through processing just can reach the requirement that oil field reinjection water standard (SY/T5329-94) or leading indicator reach GB 8978-1996 " integrated wastewater discharge standard " secondary standard.

Also there is the leach liquor that adopts alkali factory waste residue white clay ternary composite flooding water extraction to be handled as treatment agent; But the composition of the alkali factory waste residue white clay that different manufacturers or same producer produce the different periods is unfixing; Can not be accurately quantitative when causing the white clay leach liquor to be thrown in; And in the process of this treatment agent of preparation, using a large amount of acid, this might cause acid mist pollution.In addition, also there is certain restriction in leach liquor in transportation.

Summary of the invention

The present invention is directed to the deficiency that existing ternary composite flooding water extraction treatment technology or technology exist, the treatment process of a kind of low cost, high efficiency ternary composite flooding water extraction is provided.

The treatment process of ternary composite flooding water extraction of the present invention is made up of following steps:

(1) ternary composite flooding water extraction is carried out water-quality test; Test index is pH value, oleaginousness, suspension content and COD; According to the water quality situation; Oleaginousness, suspension content etc. are regulated its pH value greater than 9 smaller or equal to 12.5 with the pH regulator agent, in ternary composite flooding water extraction according to the dosage adding treatment agent of 4000mg/L-11000mg/L;

The pH regulator agent is the mixing of one or more arbitrary proportions in sodium hydroxide, calcium hydroxide, Pottasium Hydroxide and the yellow soda ash.

Treatment agent is the arbitrary proportion mixture of one or more magnesium salts in magnesium chloride, sal epsom and the magnesium nitrate.

When (2) treatment agent adds ternary composite flooding water extraction is stirred, 100 rev/mins-300 rev/mins of stirring velocitys, churning time are 2 minutes-15 minutes, and standing sedimentation is 10 minutes-30 minutes then;

(3) carry out subsequent disposal with quartz sand filtration.

For the treatment effect of ternary composite flooding water extraction, stirring is a significant effects factor.Suitable stirring velocity helps mixing of medicament, and the formation of flco can also increase the collision of flco and oil droplet and suspended substance, strengthens flco the absorption of oil droplet, suspended substance is removed.Settling time has been strengthened the coalescence of flco, also is one of important factor that influences the ternary composite flooding water extraction processing.The length of settling time is bigger to water outlet suspension content influence, and the time is short to be not enough to remove the flco of generation, but overlong time is difficult on the technology bear.Secondly, settling process can also be removed some foreign ions through the adsorption of flco.Under the normal handling condition, the sewage after the processing can reach oil field reinjection water standard (SY/T5329-94), and leading indicator can reach the requirement of GB 8978-1996 " integrated wastewater discharge standard " secondary standard.

The present invention adopts various magnesium salts cheap and easy to get as treatment agent; Not only stable components is easy to quantitatively when handling, and wide material sources; Required treatment condition are simple; Different hydraulics all there is good flexibility, can the ternary composite flooding water extraction that common technology can not be handled be handled oil field reinjection water standard (SY/T5329-94), and leading indicator reaches the requirement of GB8978-1996 " integrated wastewater discharge standard " secondary standard basically; When effectively handling ternary composite flooding water extraction, greatly reduce processing costs.

Description of drawings

Fig. 1 adopts the present invention ternary composite flooding water extraction to be handled the comparison diagram of front and back.

Embodiment

Embodiment 1

Get certain ternary compound oil drive water exit 1000mL, through water, wherein oleaginousness is 718mg/L, and COD is 1535mg/L, and the pH value was 10.5 (meet treatment condition, do not need to regulate), and suspended substance is 269mg/L.In sewage, press 6000mg/L and add the magnesium chloride treatment agent, keep 200 rev/mins of stirring velocitys, stirred 10 minutes; Standing sedimentation is 20 minutes then; Handle through quartz sand filtration again, carry out water, confirm to reach oil field reinjection water standard (SY/T5329-94); And leading indicators such as pH value, petroleum-type, suspended substance and COD reach the requirement of GB 8978-1996 " integrated wastewater discharge standard " secondary standard basically, and handle the back water conditioning.It is as shown in Figure 1 to handle front and back ternary composite flooding water extraction contrast, and the left side is the former water of ternary composite flooding water extraction, and the right side is the water after handling, and water sample obviously is divided into supernatant liquid and lower sediment after handling, and is easy to separate.Present embodiment is as shown in the table to the result of ternary composite flooding water extraction:

Table 1

Table 2

Embodiment 2

Get certain ternary compound oil drive water exit 1000mL, through water, wherein oleaginousness is 1035mg/L, and COD is 2095mg/L, and the pH value was 11.5 (meet treatment condition, do not need to regulate), and suspended substance is 339mg/L.In sewage, press the mixed processing agent of 8500mg/L adding magnesium chloride and magnesium nitrate, keep 250 rev/mins of stirring velocitys, stirred 5 minutes; Standing sedimentation is 15 minutes then; Handle through quartz sand filtration, water confirms to reach oil field reinjection water standard (SY/T5329-94) again; And leading indicators such as pH value, petroleum-type, suspended substance and COD reach the requirement of GB 8978-1996 " integrated wastewater discharge standard " secondary standard basically, and handle the back water conditioning.Present embodiment is as shown in the table to the result of ternary composite flooding water extraction:

Table 3

Table 4

Embodiment 3

Get certain ternary compound oil drive water exit 1000mL, through water, wherein oleaginousness is 615mg/L, and COD is 1311mg/L, and the pH value is 8.5, and suspended substance is 165mg/L.Regulate pH to 9 with yellow soda ash and Pottasium Hydroxide, in sewage, press 7000mg/L and add the magnesium chloride treatment agent, keep 300 rev/mins of stirring velocitys; Stirred 5 minutes, standing sedimentation is 30 minutes then, handles through quartz sand filtration again; Water; Confirm to reach oil field reinjection water standard (SY/T5329-94), and leading indicators such as pH value, petroleum-type, suspended substance and COD reach the requirement of GB 8978-1996 " integrated wastewater discharge standard " secondary standard basically, and handle the back water conditioning.Present embodiment is as shown in the table to the result of ternary composite flooding water extraction:

Table 5

Table 6

Embodiment 4

Get certain ternary compound oil drive water exit 1000mL, through water, wherein oleaginousness is 553mg/L, and COD is 1156mg/L, and the pH value is 8.7, and suspended substance is 305mg/L.Regulate pH to 9.5 with calcium hydroxide and yellow soda ash, in sewage, press the mixed processing agent that 4000mg/L adds sal epsom and magnesium nitrate, keep 300 rev/mins of stirring velocitys; Stirred 2 minutes; Standing sedimentation is 10 minutes then, handles water through quartz sand filtration; Confirm to reach oil field reinjection water standard (SY/T5329-94); And leading indicators such as pH value, petroleum-type, suspended substance reach the requirement of GB 8978-1996 " integrated wastewater discharge standard " secondary standard basically, though COD slightly exceeds standard, reach the requirement of GB 8978-1996 " integrated wastewater discharge standard " secondary standard with other sewage mixed base instincts.Present embodiment is as shown in the table to the result of ternary composite flooding water extraction:

Table 7

Table 8

Embodiment 5

Get certain ternary compound oil drive water exit 1000mL, through water, wherein oleaginousness is 1525mg/L, and COD is 3068mg/L, and the pH value is 9.7, and suspended substance is 265mg/L.Regulate pH to 12.5 with sodium hydroxide and yellow soda ash; In sewage, press the mixed processing agent of 11000mg/L adding magnesium chloride, sal epsom and magnesium nitrate, keep 100 rev/mins of stirring velocitys, stirred 15 minutes; Standing sedimentation is 30 minutes then; Handle through quartz sand filtration, water confirms to reach oil field reinjection water standard (SY/T5329-94); And leading indicators such as pH value, petroleum-type, suspended substance and COD reach the requirement of GB 8978-1996 " integrated wastewater discharge standard " secondary standard basically, and handle the back water conditioning.Present embodiment is as shown in the table to the result of ternary composite flooding water extraction:

Table 9

Table 10

Claims (1)

1. the treatment process of a ternary composite flooding water extraction is characterized in that: be made up of following steps:

(1) ternary composite flooding water extraction is carried out water-quality test; Test index is pH value, oleaginousness, suspension content and COD; According to the water quality situation, oleaginousness and suspension content, with the pH regulator agent regulate its pH value greater than 9 smaller or equal to 12.5; Dosage according to 4000mg/L-11000mg/L in ternary composite flooding water extraction adds treatment agent, and treatment agent is the arbitrary proportion mixture of one or more magnesium salts in magnesium chloride, sal epsom and the magnesium nitrate;

When (2) treatment agent adds ternary composite flooding water extraction is stirred, 100 rev/mins-300 rev/mins of stirring velocitys, churning time are 2 minutes-15 minutes, and standing sedimentation is 10 minutes-30 minutes then;

(3) carry out subsequent disposal with quartz sand filtration.