CN103449674A - Process for treating oilfield produced water by using granular diatomite - Google Patents
Process for treating oilfield produced water by using granular diatomite Download PDFInfo
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- CN103449674A CN103449674A CN2013104082044A CN201310408204A CN103449674A CN 103449674 A CN103449674 A CN 103449674A CN 2013104082044 A CN2013104082044 A CN 2013104082044A CN 201310408204 A CN201310408204 A CN 201310408204A CN 103449674 A CN103449674 A CN 103449674A
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Abstract
The invention relates to a process for treating oilfield produced water by using granular diatomite. The process comprises the following processing steps of oil separation, air flotation, anaerobic biological treatment, aerobic biological treatment, granular diatomite adsorption and filtering, and the like. By adopting the treatment process, the oilfield produced water can reach A-grade discharge standard. Aiming at the characteristics of complex organic ingredients of the oilfield produced water and high running cost of conventional biochemical-activated carbon process, the process provided by the invention has the advantages that the treatment technology is optimized, the improvement of the adsorption segment is enhanced especially, the easily generated granular diatomite is used for replacing or partially replacing the activated carbon which is expensive in price and hard in regeneration, stable and qualified discharged water is ensued, and the cost for treating the oilfield produced water is greatly reduced.
Description
Technical field
The present invention relates to a kind of waste water treatment process, in particular, relate to a kind for the treatment of Technology for Petroleum Water Flooding of applying granular diatomaceous earth.
Background technology
Oil field extracted water has the characteristics such as high oil-containing, high chemical, high organism, and its waste water water yield is large, complicated component, intractability are large.Generally be difficult to reach one-level A emission standard by biochemical treatment process, present way is normally added activated-carbon device and is carried out advanced treatment after conventional treatment process, by the method for absorption, removes remaining organic substance.Although the method is reliable and stable on technique, yet gac is expensive, cause the running cost of sewage high, caused very large economic pressures to Oil-production Enterprises.
Diatomite is after ancient times, unicellular lower plant diatom remains piled up, and what through preliminary Diagn, form a kind ofly has porous biological silicite.Its main chemical compositions is silicon-dioxide, contains a small amount of aluminum oxide, ferric oxide, calcium oxide, magnesium oxide etc. and organic.The wall shell of diatom has the micropore of a large amount of multilevel ordered arrangements, and the structure of this uniqueness has been given its many good performance, its stable chemical nature, and body is light, matter is soft, wear-resisting, heat-resisting etc., is insoluble to acid, and because porosity is large, specific surface area is large, and adsorptivity is strong.Diatomite is a kind of very general sorbent material and flocculating aids at present, is widely used in foodstuffs industry, petroleum industry and chemical industry, has aboundresources, cheap, the characteristics such as excellent performance.
Because diatomite has very strong adsorptive power and very large loading capacity, the application aspect water treatment is in recent years paid close attention to widely, especially at aspects such as advanced treatment dephosphorization, removing heavy metals, shows outstanding performance.Yet Powdered diatomite, as traditional application mode of sorbent material, has shown these living problems such as sludge yield increases suddenly, secondary pollution is serious, has also therefore limited the promotion and application of diatomite technology.
Summary of the invention
The invention provides a kind for the treatment of Technology for Petroleum Water Flooding of applying granular diatomaceous earth, this treatment process can be processed high oil-containing, high chemical, high organic oil field extracted water, water outlet can reach one-level A emission standard, solves existing activated carbon process working cost and remains high and the difficult drawback of regenerating.
The objective of the invention is to realize by following scheme:
A kind for the treatment of Technology for Petroleum Water Flooding of applying granular diatomaceous earth comprises following treatment step:
(1), oil field extracted water enters in oil trap, by the effect of oil trap, removes contained heavy oil and oil slick in waste water;
(2), the oil trap water outlet enters air flotation pool, in the mode of air-dissolving air-float, the tiny oil droplet in waste water is separated.Add chemical agent to air flotation pool and promote the air supporting performance, after separating, the gained scum silica frost is removed by skimming plant;
(3), process through air flotation pool the water scum and enter into hydrolysis acidification pool, realize acidication under the effect of microorganism, strengthen the biodegradability of waste water;
(4), the hydrolysis acidification pool water outlet enters Aerobic Pond, in the mode of blast aeration, strengthens dissolved oxygen concentration in Aerobic Pond, the organism in waste water is decomposition and inversion under microbial process, excess sludge enters the sludge treatment unit;
(5), the water processed through Aerobic Pond enters the granular diatomaceous earth adsorption filtration device, by the mode of absorption, removes remaining organism in water, by the mode of filtering, further removes suspended substance; The water of processing through the granular diatomaceous earth adsorption filtration device can reach one-level A emission standard.
The invention has the advantages that: this technique is for oil field extracted water organic components complexity, routine biochemistry-high characteristics of activated carbon process running cost, optimization process technique, emphasis is strengthened the improvement of adsorption stage, utilize the granular diatomaceous earth of easily regeneration to substitute or partly substitute the high gac of price, the assurance stable water outlet is up to standard, and greatly reduces the oil field extracted water treatment operating costs.
The accompanying drawing explanation
Below in conjunction with drawings and Examples, the invention will be further described:
Fig. 1 is process flow sheet of the present invention,
Fig. 2 is that of system flow of the present invention implements illustration.
Wherein 1 is sloping plate oil separation tank, and 2 is the air-dissolving air-float pond, and 3 is hydrolysis acidification pool, 4 is BAF, and 5 is lift pump, and 6 is primary granule diatomite adsorption filtration unit, 7 is secondary granule diatomite adsorption filtration unit, and 8 is tertiary granule diatomite adsorption filtration unit.
Embodiment
Referring to Fig. 1, Fig. 2, a kind for the treatment of Technology for Petroleum Water Flooding of applying granular diatomaceous earth of the present invention comprises following treatment step:
(1), oil field extracted water enters in oil trap, by the effect of oil trap, removes contained heavy oil and oil slick in waste water.Oil slick reclaims, and the dregs of fat are discharged to the sludge treatment unit with the form of oily sludge, and the stillness of night enters next process;
(2), the oil trap water outlet enters air flotation pool, in the mode of air-dissolving air-float, the tiny oil droplet in waste water is separated.Add chemical agent to air flotation pool and promote the air supporting performance, after separating, the gained scum silica frost is removed by skimming plant, and the stillness of night enters next process;
(3), process through air flotation pool the water scum and enter into hydrolysis acidification pool, realize acidication under the effect of microorganism, strengthen the biodegradability of waste water;
(4), the hydrolysis acidification pool water outlet enters Aerobic Pond, in the mode of blast aeration, strengthens dissolved oxygen concentration in Aerobic Pond, the organism in waste water is decomposition and inversion under microbial process, excess sludge enters the sludge treatment unit, the stillness of night enters next process;
(5), the water processed through Aerobic Pond enters the granular diatomaceous earth adsorption filtration device, by the mode of absorption, removes remaining organism in water, by the mode of filtering, further removes suspended substance; The water of processing through the granular diatomaceous earth adsorption filtration device can reach one-level A emission standard, reuse after can effluxing or further process according to practical situation.
According to oil field extracted water water quality, what described oil trap can be in advection oil separation tank, sloping plate oil separation tank, oil removing pot etc. is a kind of.
According to oil field extracted water water quality, described air flotation pool adds chemical agent, can be a kind of or arbitrary combination in the medicaments such as poly-aluminium, Polyferric Sulfate, polyacrylamide, and air flotation pool water outlet oleaginousness is down to below 20mg/L.
Described hydrolysis acidification pool is converted into biodegradable organic by the organism of difficult for biological degradation under the effect of anerobe and double oxygen bacterium, and hydrolysis acidification pool water outlet biochemical oxygen demand (BOD) and chemical oxygen demand (COD) ratio will be equal to or greater than 0.3.
Described Aerobic Pond can be any one or several combination in aeration tank, SBR pond, CASS pond, BAF, contact-oxidation pool etc., and Aerobic Pond water outlet chemical oxygen demand (COD) is 120-200mg/L.
Described granular diatomaceous earth adsorption filtration device is strict plug flow reactor, and reactor cross section can be rectangle, circle or other shapes.
Described granular diatomaceous earth adsorption filtration device can be in the absorption of single stage adsorption, double stage tandem or plural serial stage absorption a kind of, can specifically arrange according to the water quantity and quality situation.
In described granular diatomaceous earth adsorption filtration device, granular diatomaceous earth adopts one-level diatomite sintering to make, and sintering temperature is 1000-1200 ℃; The granular diatomaceous earth particle diameter is 1-5mm; Tap density is 0.75g/cm
3; Angle of repose is 23 °; The granular diatomaceous earth optimal adsorption time is 60min.
In described granular diatomaceous earth adsorption filtration device, after granular diatomaceous earth absorption is saturated under 500-600 ℃ of high temperature calcination 1-2h can realize effective regeneration; Temperature can reach the device of 500-600 ℃ and all can be used for granular diatomaceous earth regeneration, without special-purpose regenerating unit.
In described granular diatomaceous earth adsorption filtration device, granular diatomaceous earth shows stronger absorption property for the polynary halohydrocarbon of oil field extracted water small molecular, as methylene dichloride, tetracol phenixin etc.
Below in conjunction with the drawings and specific embodiments, the present invention will be further described.
Shown in Fig. 2 is an a kind of embodiment who has applied the treatment Technology for Petroleum Water Flooding of granular diatomaceous earth of the present invention, comprise following treatment step: (1) oleaginousness 3000mg/L oil field extracted water enters in sloping plate oil separation tank 1, contained oil slick, coarse particles oil and heavy oil in waste water is removed in effect by oil trap 1, and the water outlet oleaginousness can be down to 200mg/L; (2) oil trap 1 water outlet enters air-dissolving air-float pond 2, air flotation pool 2 water outlet oleaginousness 20mg/L, and the waste water that process through air flotation pool 2 (3) enters hydrolysis acidification pool 3, strengthens the biodegradability of waste water; (4) hydrolysis acidification pool 3 water outlets enter BAF 4, and BAF 4 water outlet chemical oxygen demand (COD) are down to below 120mg/L; (5) BAF 4 water outlets enter tertiary granule diatomite adsorption filtration unit 6,7,8 successively through promoting water pump 5, under the synergy of absorption and filtration, chemical oxygen demand (COD) descends gradually, primary granule diatomite adsorption filtration unit 6 water outlet chemical oxygen demand (COD) are about 80-90mg/L, secondary granule diatomite adsorption filtration unit 7 water outlet chemical oxygen demand (COD) are about 60-70mg/L, and tertiary granule diatomite adsorption filtration unit 8 water outlet chemical oxygen demand (COD) are down to below 50mg/L; 8 water outlets of tertiary granule diatomite adsorption device reach one-level A emission standard and efflux.
In this embodiment, granular diatomaceous earth adopts one-level diatomite sintering to make, and sintering temperature is 1000-1200 ℃; The granular diatomaceous earth particle diameter is 1-5mm; Tap density is 0.75g/cm
3; Angle of repose is 23 °; The granular diatomaceous earth single stage adsorption time is 20min, and total adsorption time is 60min.
In this embodiment, after granular diatomaceous earth is saturated, be placed in rotary kiln calcination 2h, but effective regeneration, and regeneration rate surpasses 98%.
In this embodiment, after treatment, in final outflow water, acetone, methylene dichloride, toluene, n-undecane, tetracol phenixin, benzene equal size all are less than 1ug/L to oil field extracted water.
Claims (10)
1. a treatment Technology for Petroleum Water Flooding of applying granular diatomaceous earth comprises following treatment step:
(1), oil field extracted water enters in oil trap, by the effect of oil trap, removes contained heavy oil and oil slick in waste water;
(2), the oil trap water outlet enters air flotation pool, in the mode of air-dissolving air-float, the tiny oil droplet in waste water is separated; Add chemical agent to air flotation pool and promote the air supporting performance, after separating, the gained scum silica frost is removed by skimming plant;
(3), process through air flotation pool the water scum and enter into hydrolysis acidification pool, realize acidication under the effect of microorganism, strengthen the biodegradability of waste water;
(4), the hydrolysis acidification pool water outlet enters Aerobic Pond, in the mode of blast aeration, strengthens dissolved oxygen concentration in Aerobic Pond, the organism in waste water is decomposition and inversion under microbial process, excess sludge enters the sludge treatment unit;
(5), the water processed through Aerobic Pond enters the granular diatomaceous earth adsorption filtration device, by the mode of absorption, removes remaining organism in water, by the mode of filtering, further removes suspended substance; The water of processing through the granular diatomaceous earth adsorption filtration device can reach one-level A emission standard.
2. treatment process according to claim 1, in step (1), what described oil trap can be in advection oil separation tank, sloping plate oil separation tank, oil removing pot etc. is a kind of.
3. treatment process according to claim 1, in step (2), according to oil field extracted water water quality, described air flotation pool adds chemical agent, can be one or more the combination in the medicaments such as poly-aluminium, Polyferric Sulfate, polyacrylamide, air flotation pool water outlet oleaginousness be down to below 20mg/L.
4. treatment process according to claim 1, in step (3), described hydrolysis acidification pool is converted into biodegradable organic by the organism of difficult for biological degradation under the effect of anerobe and double oxygen bacterium, and hydrolysis acidification pool water outlet biochemical oxygen demand (BOD) and chemical oxygen demand (COD) ratio will be equal to or greater than 0.3.
5. treatment process according to claim 1, in step (4), described Aerobic Pond can be any one or several combination in aeration tank, SBR pond, CASS pond, BAF, contact-oxidation pool etc., and Aerobic Pond water outlet chemical oxygen demand (COD) is 120-200mg/L.
6. treatment process according to claim 1, in step (5), described granular diatomaceous earth adsorption filtration device is strict plug flow reactor; Reactor cross section can be rectangle, circle or other shapes; The granular diatomaceous earth adsorption filtration device can be in the absorption of single stage adsorption, double stage tandem or plural serial stage absorption a kind of, can specifically arrange according to the water quantity and quality situation.
7. according to the described treatment process of claim 1 or 6, in step (5), the granular diatomaceous earth particle diameter is 1-5mm; Tap density is 0.75g/cm
3; Angle of repose is 23 °; The granular diatomaceous earth optimal adsorption time is 60min.
8. treatment process according to claim 1 comprises following treatment step:
(1) oleaginousness 3000mg/L oil field extracted water enters in sloping plate oil separation tank, by the effect of oil trap, removes contained oil slick, coarse particles oil and heavy oil in waste water, and the water outlet oleaginousness can be down to 200mg/L;
(2) the oil trap water outlet enters the air-dissolving air-float pond, air flotation pool water outlet oleaginousness 20mg/L,
(3) waste water of processing through air flotation pool enters hydrolysis acidification pool, strengthens the biodegradability of waste water;
(4) the hydrolysis acidification pool water outlet enters BAF, and the effluent of aeration biological filter chemical oxygen demand (COD) is down to below 120mg/L;
(5) effluent of aeration biological filter enters tertiary granule diatomite adsorption filtration unit successively through promoting water pump, under the synergy of absorption and filtration, chemical oxygen demand (COD) descends gradually, primary granule diatomite adsorption filtration unit water outlet chemical oxygen demand (COD) is about 80-90mg/L, secondary granule diatomite adsorption filtration unit water outlet chemical oxygen demand (COD) is about 60-70mg/L, and tertiary granule diatomite adsorption filtration unit water outlet chemical oxygen demand (COD) is down to below 50mg/L; The water outlet of tertiary granule diatomite adsorption filtration unit reaches one-level A emission standard and effluxes.
9. treatment process according to claim 8, in step (5), described granular diatomaceous earth particle diameter is 1-5mm; Tap density is 0.75g/cm
3; Angle of repose is 23 °; The granular diatomaceous earth single stage adsorption time is 20min, and total adsorption time is 60min.
10. the granular diatomaceous earth used in claim 6 or 9, be to adopt one-level diatomite sintering to make, and sintering temperature is 1000-1200 ℃;
In described granular diatomaceous earth adsorption filtration device, after granular diatomaceous earth absorption is saturated under 500-600 ℃ of high temperature calcination 1-2h can realize effective regeneration; Temperature can reach the device of 500-600 ℃ and all can be used for granular diatomaceous earth regeneration, without special-purpose regenerating unit;
In described granular diatomaceous earth adsorption filtration device, granular diatomaceous earth shows stronger absorption property for the polynary halohydrocarbon of oil field extracted water small molecular, as methylene dichloride, tetracol phenixin etc.
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Cited By (4)
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| CN105481090A (en) * | 2015-12-29 | 2016-04-13 | 北京京城环保股份有限公司 | Granular kieselguhr-applied denitrification filter device and method |
| CN105923930A (en) * | 2016-07-08 | 2016-09-07 | 吴印强 | Biological treatment technology for sewage |
| CN109502675A (en) * | 2018-12-15 | 2019-03-22 | 浙江大学自贡创新中心 | A kind of high efficiency oil-water separation method for different oil droplet sizes |
| CN110183045A (en) * | 2019-06-03 | 2019-08-30 | 拜城县众泰煤焦化有限公司 | Biochemical automatic control device |
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| CN105481090A (en) * | 2015-12-29 | 2016-04-13 | 北京京城环保股份有限公司 | Granular kieselguhr-applied denitrification filter device and method |
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| CN110183045A (en) * | 2019-06-03 | 2019-08-30 | 拜城县众泰煤焦化有限公司 | Biochemical automatic control device |
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