A kind of well-drilling waste water deep treatment method based on the ozone composite catalytic oxidation
Technical field
The present invention relates to a kind of treatment process of well-drilling waste water, be specifically related to adopt ozone composite catalytic oxidation technology that well-drilling waste water is carried out the method for advanced treatment, belong to petroleum prospecting, development field.
Background technology
Well-drilling waste water comes from the various water of productive use in depleted drilling fluid and the drilling process; Wherein, The objectionable constituent that cause environmental pollution are the low-molecular-weight organic compound that produces of oils, salt, sterilant, some chemicaladditives, heavy metal (like mercury, copper, chromium, cadmium, zinc, lead etc.), macromolecular organic compound biological degradation and alkaline matter etc., thereby major pollution indexs such as the colourity of causing, COD, SS, petroleum-type exceed standard in a large number.The composition of well-drilling waste water and concentration change along with the variation of stratal configuration, mud system, drilling well well depth in addition, also have characteristics such as polytropy, complicacy, dispersiveness.Because the contaminative of well-drilling waste water is stronger, if not treated direct discharging will cause significant damage to environment, therefore solve the well-drilling waste water COD problem that exceeds standard, become the key of handling well-drilling waste water.
At present, the main technique methods of both at home and abroad well-drilling waste water being handled can reduce: physics method, chemical method, biological process, physical-chemical method.Wherein physics method and physical-chemical treatment technology are commonly used in the well-drilling waste water pretreatment stage, comprise coagulating treatment method, neutralization-coagulating treatment method, acid-alkali treatment method etc.These methods are higher to suspended substance, colloidal clearance, but are difficult to remove for a large amount of dissolved organic matters that exist in the water body.For solving this type of problem, also need carry out advanced treatment, mainly comprise: chemical oxidization method, biological treatment, charcoal absorption etc.Yet these methods all have weak point separately, and are little like activated carbon adsorptive capacity, and cost is higher; Hypochlorite oxidation efficient is low, if adopt catalyzer can cause the loss of nickel again, introduces new pollutent cl ions simultaneously.Fenton agent treated effect is better, also can not cause secondary pollution but the reaction times long, it can't satisfy in the oil field operation fast, simple requirement.Because the toxicity of well-drilling waste water is high, the practicality that biological treatment is handled well-drilling waste water is lower in addition.So, seek a kind of fast, convenient, can be extremely urgent with the Technology of effective processing to unmanageable waste drilling fluid.
Summary of the invention
The objective of the invention is to current well-drilling waste water treatment effect is relatively poor, cost is higher present situation, a kind of low cost, effective, the method that can handle well-drilling waste water continuously are provided, concrete steps are following:
(1) regulating waste water ph is 8~9;
(2) waste water of regulating after the pH value carries out coagulating treatment, adds coagulating agent when being settled down to the supernatant turbidity and being 10~30NTU, pumps supernatant liquid, and accent clear liquid pH value is 2~4;
(3) waste water after the adjusting pH value in the step (2) is carried out little electrolysis treatment in little electrolyzer; Be filled with interior electrolysis filler in little electrolyzer, the waste water in the step (2) behind the adjust pH and the weight ratio of this filler are 1: 1.5~1: 3, add ydrogen peroxide 50, waste water and H when waste water is handled in little electrolyzer
2O
2Weight ratio be 1000: 1~12, oxidization time is 0.5~4 hour;
(4) waste water after step (3) is handled gets into settling tank, and regulating waste water ph is 8~12, deposition;
(5) add ozone in the waste water after step (4) is handled, every liter of waste water adds 280~900mg O
3, in oxidation reactor, handle;
(6) be filled with the solid heterogeneous catalyzer in the oxidation reactor, the solid heterogeneous catalyst volume is 1: 3~1: 6 with the ratio of oxidation reactor volume; The reaction times of waste water in oxidation reactor is 20~40 minutes;
(7) efflux behind the waste water filtering after the processing.
In the present invention; Adding ozone in the said step (5) mainly is the advanced oxidation function of utilizing ozone, and the adding mode of ozone is removed aeration mode commonly used and added the waste water China and foreign countries, can also between settling tank and oxidation reactor, set up a mixing jet device; Be connected with ozonizer on the mixing jet device; Ozonizer can produce ozone, and the waste water after step (4) is handled is pumped from settling tank by water pump, and when flowing through the mixing jet device; Open ozonizer, the ozone concn in the ozonizer exit gas is controlled to be 70~90mg/L; When waste water is flowed through the mixing jet device; Can produce negative pressure; Utilize this negative pressure that gas ozoniferous is sucked in the mixing jet device; In the mixing jet device, carry out two of gas and waste water and mix back entering oxidation reactor mutually, the gas flow that the mixing jet device sucks is 4: 1~10: 1 with the ratio through the wastewater flow in the mixing jet device; The solid heterogeneous catalyzer is housed in the oxidation reactor, and the solid heterogeneous catalyst volume is 1: 3~1: 6 with the ratio of oxidation reactor volume, realizes with OH
-And H
2O
2Be master's the homogeneous catalysis process and the composite catalyzing process of solid heterogeneous catalyzer, the reaction times of waste water in oxidation reactor is 20~40 minutes;
To the coagulating agent described in the above-mentioned steps (2), preferably by CaCl
2, PJJ, the composite coagulating agent that forms of PAC, CaCl
2, PJJ, PAC weight ratio be 1: 1.5: 1.5.Interior electrolysis filler described in the above-mentioned steps (3), preferred iron, copper and carbon granule agglomerating filler, the weight ratio of iron, copper, carbon is 1: 0.1: 1.2.The preferred TiO of solid heterogeneous catalyzer described in the above-mentioned steps (5)
2The catalyzer of carried with doped rare earth metal Ru.
Ultimate principle of the present invention is: (1) Coagulation Method is to destroy colloidal stability through dosing coagulant in water body; Colloidal particle (abbreviation micelle) is flocculated, produce throw out, and adsorption takes place; Pollutent in the waste water is attached together, then sedimentation and with the method for water sepn.This method mainly is to utilize electrostatic double layer compression, static neutralization, adsorption bridging, deposition net the mechanism of action such as to catch.Solid-liquid separation is PM for particulate matter sedimentation under the effect of gravity.(2) waste water of slant acidity is in little electrolyzer; Making anode, carbon or other materials with iron or other metals makes negative electrode and in water, forms numerous microbattery field; Thereby generation micro-electrolysis reaction; The Sauerstoffatom of the nascent state that reaction produces has extremely strong oxidisability, part inorganics and organism in the oxidable water; The Sauerstoffatom of produced simultaneously nascent state has very strong reductive action, makes some material in the sewage be able to reduction; In addition, because organism is participated in the reduction reaction of negative electrode, make functional group that variation take place; Change former organic properties; And the dissolved positively charged ion can form hydroxo complex in the water, in sewage, plays coagulation, assists in removing suspended matter and colloidal impurity in the waste water.(3) newly-generated in the sewage after little electrolysis treatment have a large amount of Fe
2+, therefore can be used as catalyzer and strengthen H
2O
2Oxidation capacity forms classical Fenton reagent, alleviates the organic loading of follow-up ozone oxidation part greatly.(4) ozone is a kind of strong oxidizer; Under the condition of alkalescence and catalyzer existence; Ozone is to be main with indirect reaction; Ozone can decompose and produces that the secondary oxidation agent---hydroxyl radical free radical (OH), OH have the oxidation capacity stronger than ozone, with water in have advantages such as speed of response is fast, non-selectivity, non-secondary pollution during the organism reaction.
Among the present invention, if use the agglomerating filler of iron, copper and carbon granule, the replacement cycle is 4~6 months; The Fe that electrolytic process generated in the Fenton oxidation mainly utilized
2+, need not to add ferrous salt as catalyzer; If mainly through the air preparation, running cost is mainly the cost of power consumption and catalyzer for self-control ozone, the preparation of ozone; Adopt the present invention that the coking chemical waste water through biochemical treatment is carried out advanced treatment, water outlet COD<100mg/L, chroma removal rate, sulfide clearance are near 100%, to the environment non-secondary pollution.
Description of drawings
Fig. 1 is the well-drilling waste water concentration processing technological flow synoptic diagram based on the ozone composite catalytic oxidation according to the invention.
1-continues batch reactor 2-acid storage 3-volume pump
Electrolyzer 6-settling tank in the 4-dioxygen tank 5-
7-lye vat 8-sump pump 9-mixing jet device
10-ozonizer 11-oxidation reactor 12-strainer
13-water outlet 14-offgas duct 15-tail gas cracker
16-volume pump 17-volume pump 18-solid heterogeneous catalyzer
19-line mixer 20-sump pump
Embodiment
Embodiment one
Well-drilling waste water 110L is pumped into continuous batch reactor 1, and using NaOH to regulate waste water ph is 8, adds CaCl
2, PJJ, the composite coagulating agent 0.2kg of PAC, CaCl
2, PJJ, PAC weight ratio 1: 1.5: 1.5.After the sedimentation 4 hours, the supernatant turbidity is 10NTU.Supernatant liquid is pumped in the line mixer 19, utilize volume pump 3 that the hydrochloric acid in the acid storage 2 is joined in the clear liquid that pumps simultaneously, utilize line mixer 19 to carry out thorough mixing, control pH value is 2.Waste water 80L after the adjusting pH value gets into little electrolyzer 5 and carries out little electrolysis treatment; Be filled with iron, copper and carbon granule agglomerating filler in little electrolyzer, the weight ratio of iron, copper, carbon is 1: 0.1: 1.2, and waste water is 1: 1.5 with the filler weight ratio; Filler weight is 120kg; During the processing, adding 0.3L concentration is 27% ydrogen peroxide 50, oxidation 4 hours.Waste water after the processing is put into settling tank 6, utilizes volume pump 17 that the NaOH solution in the lye vat 7 is joined in the settling tank 6, regulates pH and is 8 and precipitate.Deposition pumps into oxidation reactor 11 with the upper strata waste water in the settling tank after accomplishing, and adds 280mg ozone by every liter of waste water; Be filled with 53L TiO in the oxidation reactor 11
2The solid heterogeneous catalyzer of carried with doped rare earth metal Ru, oxidation reactor 11 volumes are 1: 3 with solid heterogeneous catalyst volume ratio; The remainder of the ydrogen peroxide 50 that before adds will be participated in reaction, realizes with OH
-And H
2O
2Be master's the homogeneous catalysis process and the composite catalyzing process of solid heterogeneous catalyzer, the reaction times is 40 minutes.Waste water filtering after the processing effluxes again.The tail gas that contains drop ozone discharges after through the heating pyrolyze device.
Embodiment two
Well-drilling waste water 200L is pumped into continuous batch reactor 1, and using unslaked lime to regulate waste water ph is 9, adds the composite coagulating agent 2kg of PAC and PAM.After the sedimentation 6 hours, the supernatant turbidity is 20NTU, and supernatant liquid is pumped in the line mixer 19, utilizes volume pump 3 that the hydrochloric acid in the acid storage 2 is joined in the clear liquid that pumps simultaneously, utilizes line mixer 19 to carry out thorough mixing, and control pH value is 4.Waste water 160L after the adjusting pH value gets into little electrolyzer 5 and carries out little electrolysis treatment, is filled with Fe/Cu galvanic cell filler in little electrolyzer, and waste water is 1: 2 with the filler weight ratio; Filler weight is 320kg; During the processing, adding 7.1L concentration is 27% ydrogen peroxide 50, oxidation 0.5 hour.Waste water after handling is put into settling tank 6, utilize volume pump 17 that the NaOH solution in the lye vat 7 is joined in the settling tank 6, regulate pH and be 12 and precipitate.Deposition pumps into mixing jet device 9 with the upper strata waste water in the settling tank after accomplishing, and opens ozonizer 10 simultaneously; The mass concentration of ozone is 90mg/L in the ozonizer 10 exit end gases; The negative pressure of utilizing mixing jet device 9 to produce sucks gas in the mixing jet device 9, and the gas flow that the mixing jet device sucks is 6: 1 with the ratio through the wastewater flow in the mixing jet device; Wastewater flow is 6L/min; After gas ozoniferous was inhaled in the mixing jet device 9, the waste water thorough mixing with getting into wherein got into oxidation reactor 11 in the lump; Be filled with 27L Al in the oxidation reactor 11
2O
3Load MnO
xSolid metal catalyst, oxidation reactor 11 volumes are 1: 6 with solid heterogeneous catalyst volume ratio, realize with OH
-And H
2O
2Be master's the homogeneous catalysis process and the composite catalyzing process of solid heterogeneous catalyzer.Can directly efflux behind the waste water filtering after the processing.The tail gas that contains drop ozone discharges after through the heating pyrolyze device.
Embodiment three
Well-drilling waste water 250L is pumped into continuous batch reactor 1, and using NaOH to regulate waste water ph is 9, adds the composite coagulating agent 1.2kg of PAC, PJJ and PAM.After the sedimentation 5 hours, the supernatant turbidity is 30NTU, and supernatant liquid is pumped in the line mixer 19, utilizes volume pump 3 that the hydrochloric acid in the acid storage 2 is joined in the clear liquid that pumps simultaneously, utilizes line mixer 19 to carry out thorough mixing, and control pH value is 3.Waste water 200L after the adjusting pH value gets into little electrolyzer 5 and carries out little electrolysis treatment, is filled with the Fe/Cu/C filler in little electrolyzer, and waste water is 1: 1.5 with the filler weight ratio; Filler weight is 300kg; During the processing, adding 5.3L concentration is 30% ydrogen peroxide 50, oxidation 2 hours.Waste water after handling is put into settling tank 6, utilize volume pump 17 that the NaOH solution in the lye vat 7 is joined in the settling tank 6, regulate pH and be 10 and precipitate.Deposition pumps into mixing jet device 9 with the upper strata waste water in the settling tank after accomplishing, and opens ozonizer 10 simultaneously; The mass concentration of ozone is 90mg/L in ozonizer 10 exit gass; The negative pressure of utilizing mixing jet device 9 to produce sucks gas in the mixing jet device 9, and the gas flow that mixing jet device 9 sucks is 10: 1 with the ratio through the wastewater flow in the mixing jet device 9; Wastewater flow is 4L/min; After gas ozoniferous was inhaled in the mixing jet device 9, the waste water thorough mixing with getting into wherein got into oxidation reactor 11 in the lump; Be filled with 32L Al in the oxidation reactor 11
2O
3Load Fe ionic solid metal catalyst, oxidation reactor 11 volumes are 1: 5 with solid heterogeneous catalyst volume ratio, realize with OH
-And H
2O
2Be master's the homogeneous catalysis process and the composite catalyzing process of solid heterogeneous catalyzer, the reaction times is 25 minutes.Can directly efflux behind the waste water filtering after the processing.The tail gas that contains drop ozone is recyclable.
Embodiment four
Well-drilling waste water 340L is pumped into continuous batch reactor 1, and using NaOH to regulate waste water ph is 8, adds the composite coagulating agent 1.5kg of PAC, PJJ and PAM.After the sedimentation 4 hours, the supernatant turbidity is 25NTU, and supernatant liquid is pumped in the line mixer 19, utilizes volume pump 3 that the hydrochloric acid in the acid storage 2 is joined in the clear liquid that pumps simultaneously, utilizes line mixer 19 to carry out thorough mixing, and control pH value is 3.Waste water 300L after the adjusting pH value gets into little electrolyzer 5 and carries out little electrolysis treatment, is filled with the Fe/Cu/C filler in little electrolyzer, and waste water is 1: 3 with the filler weight ratio; Filler weight is 900kg; During the processing, adding 5L concentration is 30% ydrogen peroxide 50, oxidation 3 hours.Waste water after handling is put into settling tank 6, utilize volume pump 17 that the NaOH solution in the lye vat 7 is joined in the settling tank 6, regulate pH and be 9 and precipitate.Deposition pumps into mixing jet device 9 with the upper strata waste water in the settling tank after accomplishing, and opens ozonizer 10 simultaneously; The mass concentration of ozone is 70mg/L in ozonizer 10 exit gass; The negative pressure of utilizing mixing jet device 9 to produce sucks gas in the mixing jet device 9, and the gas flow that mixing jet device 9 sucks is 4: 1 with the ratio through the wastewater flow in the mixing jet device 9; Wastewater flow is 4L/min; After gas ozoniferous was inhaled in the mixing jet device 9, the waste water thorough mixing with getting into wherein got into oxidation reactor 11 in the lump; Be filled with 32L Al in the oxidation reactor 11
2O
3Load Fe ionic solid metal catalyst, oxidation reactor 11 volumes are 1: 5 with solid heterogeneous catalyst volume ratio, realize with OH
-And H
2O
2Be master's the homogeneous catalysis process and the composite catalyzing process of solid heterogeneous catalyzer, the reaction times is 30 minutes.Can directly efflux behind the waste water filtering after the processing.The tail gas that contains drop ozone is recyclable.