A kind of concentrated surfactant waste water treatment process
Technical field
The invention belongs to water-treatment technology field, can be used for the process of concentrated surfactant waste water (COD >=5000mg/L).
Background technology
Tensio-active agent (surfactant), refer to that there is fixing hydrophilic and oleophilic group, align in the surface energy of solution, and the material that surface tension significantly declines can be made, there is good solubilising, emulsification, wetting, suspending, foaming and froth breaking, sterilization, sterilization, anti-water hardness tolerance and cleaning function, anion surfactant, cats product and nonionogenic tenside can be divided into, be widely used in production, life.In production and use procedure; a large amount of surface active agent wastewater that contains inevitably enters in physical environment; its in the environment a large amount of existence can cause serious harm to the ecosystem, the process of surface active agent wastewater for protection of the environment, promote socio-economic development all tool be of great significance.
Existing tensio-active agent preconditioning technique comprises foamet, absorption method, Coagulation Method, membrane separation process, catalytic oxidation and biological process etc.
Foamet refers to and passes into air in containing surface active agent wastewater and produce a large amount of bubble, makes the SURFACTANT ADSORPTION in waste water form foam in bubble surface and rise to the water surface to form foam layer, and scumming layer both can make waste water be purified.A large amount of tests and engineering practice prove, foamet is only suitable for the lower surface active agent wastewater process of concentration, causes foam volume excessive during excessive concentration, cleaning difficulty, and foam layer is follow-up cannot process.
Absorption method is the porousness and the bigger serface that utilize sorbent material, the pollutent in waste water is adsorbed on surface thus reaches the object of separation.Conventional sorbent material has gac, polymeric adsorbent, diatomite and kaolin etc.For lower concentration surfactant waste water absorption method, there is the shortcomings such as speed is fast, good stability, equipment take up an area the advantages such as little, but there is adsorbent reactivation difficulty for concentrated surfactant waste water, and working cost is high, and pre-processing requirements is high.
Coagulation Method adds coagulating agent in surface active agent wastewater, the flco utilizing coagulating agent to produce on the one hand removes the tensio-active agent be adsorbed on colloid, utilizes the tensio-active agent generation chemical reaction in coagulating agent and aqueous phase to form the precipitation of insoluble on the other hand.The method is better to process anion surfactant effect, but limited to nonionogenic tenside removal effect, for negatively charged ion and nonionic compound wastewater must with other treatment process with the use of.
Membrane separation process utilizes the Thief zone selectivity of film to come solvent in separation solution and solute, and conventional membrane sepn has reverse osmosis, ultrafiltration, micro-filtration, electrodialysis etc., and wherein ultrafiltration and nanofiltration Surfactant have good removal effect.But for concentrated surfactant waste water, pretreatment technology is complicated, film easily pollutes, clean difficulty, working cost is high.
Catalytic oxidation produces hydroxyl radical, organic method in oxidized waste water in the effect of luminous energy, electric energy or redox agent.The effects such as the air supporting of catalytic oxidation simultaneous and flocculation.Conventional method has photocatalytic oxidation, By Electrocatalytic Oxidation and electric flocculence etc.Catalytic oxidation is obvious for low concentration surfactant water treatment effect, generally as the pretreatment unit before surface active agent wastewater biochemical process.Treatment effect for concentrated surfactant waste water is then undesirable.
Summary of the invention
Technical problem to be solved by this invention is the deficiency overcoming above-mentioned background technology, provides the concentrated surfactant waste water treatment process that a kind of technological process is simple, easy and simple to handle, working cost is low, treatment effect is good.
The technical problem to be solved in the present invention is achieved through the following technical solutions:
A kind of concentrated surfactant waste water treatment process, carries out according to following steps successively:
1) acidolysis: add sulfuric acid and mix while stirring surface active agent wastewater, regulate the pH value 1-2 of this waste water, staticly settle 1.5-2h, get supernatant liquor;
2) extract: in step 1) add chloroform in the ratio of 30-50mL/L waste water in the supernatant liquor that obtains, staticly settle after fully stirring;
3) coagulating sedimentation: get step 2) supernatant liquor that obtains, add NaOH solution and regulate waste water ph to neutral, add calcium chloride, coagulating agent and coagulant aids simultaneously, fully stir, staticly settle.
Churning time in described hydrolysis step is not less than 1h, staticly settles 1.5-2h.
The mix and blend time in described extraction step is not less than 1.5h, staticly settles time 1.5-2h.
In described coagulating sedimentation step, the neutrality of waste water is pH value 7.5-8.5;
In described coagulating sedimentation step, calcium chloride (CaCl
2) dosage 0.5-1.5g/L;
In described coagulating sedimentation step, coagulating agent is polymerize aluminum chloride (PAC), dosage 300-500mg/L, and coagulant aids is polyacrylamide (PAM), dosage 2-4mg/L, and the mix and blend time is not less than 1.5h, staticly settles 4-6h.
In described extraction step, the extract extracted after supernatant liquor enters chloroform recirculation system, and make it be heated to chloroform boiling point (61 ~ 62 DEG C), then cool and isolate chloroform and extract, the chloroform of extraction recycles.
Described chloroform recirculation system adopts electric energy or steam to heat, and supporting chloroform vapor cooling recycling pipeline, continues to recycle after reclaiming chloroform.
Accompanying drawing explanation
Fig. 1 process flow diagram of the present invention.
Embodiment
Concrete engineering embodiment of the present invention is realized (see accompanying drawing) by following technique unit and equipment:
1, acidolysis process unit: be made up of pH Controlling System, acidolysis reaction pond and acidolysis settling tank.PH Controlling System is linked by industrial acidity meter and acid adding volume pump, the pH value of setup control solution is limited to 1-2 up and down, realize stopping dosing (mass concentration 10% sulphuric acid soln) when pH value of solution is less than 1, pH starts dosing (mass concentration 10% sulphuric acid soln) when being greater than 2, the pH value of regulator solution between 1 and 2; Coagulation reaction tank adopts circular or square structure, supporting oar blade type mixing and blending machine one; Settling tank adopts common vertical sedimentation tank, and settling tank supernatant liquor enters extraction process cell processing, bottom sludge concentration desiccation process.
2, extraction process unit: be made up of extractive reaction section, precipitation separation section and chloroform circulation and stress section.Extractive reaction section adopts circular configuration, and supporting rotating speed is not less than the paddle agitator one of 200r/m; Precipitation separation section adopts circular stainless steel constant volume groove, and be separated according to the volume adding chloroform is corresponding, top waste water enters coagulating sedimentation cell processing, and bottom chloroform and extract enter chloroform recirculation system; Chloroform recirculation system adopts circular or rectangle structure, electric energy or steam is adopted to heat, temperature control device control temperature is utilized to make chloroform and extract evaporation for 61-62 DEG C (chloroform boiling point), supporting chloroform vapor cooling recycling pipeline, chloroform is reclaimed and continues on for extractive reaction, the organism extracted can burn with the proportions of fire coal according to 1:10.
3, coagulating sedimentation unit: be made up of pH Controlling System, coagulation reaction tank and settling tank.PH Controlling System by industrial acidity meter with add alkali volume pump and link, the pH value of setup control is limited to 7.5-8.5 up and down, realize stopping dosing (mass concentration 10%NaOH solution) when pH value of solution is greater than 8.5, pH starts dosing (mass concentration 10%NaOH solution) when being less than 7.5, the pH value of regulator solution is between 7.5-8.5; Coagulation reaction tank adopts circular or square structure, supporting oar blade type mixing and blending machine one; Settling tank adopts common vertical sedimentation tank, and settling tank supernatant liquor enters the process of next workshop section, bottom sludge concentration desiccation process; System dosing all adopts METERING DIAPHRAGM PUMPS to add, and ensures dosing precision.
Embodiment 1
The high concentration anionic surfactant of daily use chemicals industry, COD is at 5000mg/L
1) acidolysis: the sulphuric acid soln adding mass concentration 10% while stirring surface active agent wastewater mixes, and regulates the pH value to 2 of this waste water, then staticly settles, get supernatant liquor; Churning time 1.3h, staticly settles time 1.8h.
2) extract: in step 1) add chloroform in the ratio of 50mL/L waste water in the supernatant liquor that obtains, staticly settle after fully stirring, get supernatant liquor; Churning time 1.5h, staticly settles time 1.5h.
3) coagulating sedimentation: get the supernatant liquor that step 2 obtains, the NaOH solution dropping into mass concentration 10% regulates waste water ph to 8.5, adds calcium chloride 500mg/L, coagulant polymeric aluminium chloride 300mg/L and coagulant aids polyacrylamide 2mg/L simultaneously, stir 1.5h, staticly settle 4h.
After testing, the COD of processed waste water is 450mg/L.
Embodiment 2
The nonionogenic tenside of daily use chemicals industry, COD is at 12000mg/L
1) acidolysis: the sulphuric acid soln adding mass concentration 30% while stirring surface active agent wastewater mixes, and regulates the pH value to 1.5 of this waste water, then staticly settles, get supernatant liquor; Churning time 1.1h, staticly settles time 1.5h.
2) extract: in step 1) add chloroform in the ratio of 40mL/L waste water in the supernatant liquor that obtains, staticly settle after fully stirring, get supernatant liquor; Churning time 1.6h, staticly settles time 1.7h.
3) coagulating sedimentation: get extraction step 1) supernatant liquor that obtains, the OH solution adding mass concentration 10%Na regulates waste water ph to 8.0, add calcium chloride 700mg/L simultaneously, coagulant polymeric aluminium chloride 400mg/L and coagulant aids polyacrylamide 3mg/L, stir 1.7h, staticly settle 4.5h.
After testing, the COD of processed waste water is 1150mg/L.
Embodiment 3
The high concentration anionic surfactant of metal-working industry and nonionogenic tenside compound wastewater, COD is at 210000mg/L.
1) acidolysis: the sulphuric acid soln adding mass concentration 50% while stirring surface active agent wastewater mixes, and regulates the pH value to 1 of this waste water, then staticly settles, get supernatant liquor; Churning time 1.2h, staticly settles time 2h.
2) extract: in step 1) add chloroform in the ratio of 50mL/L waste water in the supernatant liquor that obtains, staticly settle after fully stirring, get supernatant liquor; Churning time 1.8h, staticly settles time 1.8h.
3) coagulating sedimentation: get step 2) supernatant liquor that obtains, the NaOH solution adding mass concentration 10% regulates waste water ph to 7.5, adds calcium chloride 1000mg/L, coagulant polymeric aluminium chloride 500mg/L and coagulant aids polyacrylamide 4mg/L simultaneously, stir 2h, staticly settle 5h.
After testing, the COD of processed waste water is 20000mg/L.
Above-described embodiment proves: the clearance of Surfactant waste water COD of the present invention is more than 90%.