A kind of offshore platform domestic sewage processing methodTechnical field
The present invention relates to sanitary sewage disposal, particularly relate to the treatment process of marine oil production vessel, drilling unit, floating type production, storage and offloading device (FPSO) and oceangoing vessel sanitary sewage.
Background technology
Offshore platform sanitary sewage refers to the sewage (being commonly called as Heisui River) containing excrement, urine that platform lavatory is discharged, the sewage containing washing composition that the kitchen in platform production facility district, toilet, washing place discharge and the sewage (being commonly called as buck) that consulting room is got rid of.
For protecting the marine environment; country comes into effect " offshore oil exploration and exploitation Pollutant emission concentration limit value " (GB4914-2008) standard on May 1st, 2009; regulation is made to the COD limit value that offshore oil exploration and exploitation is arranged in extra large sanitary sewage, has seen the following form.
Sanitary sewage emission concentration limit value unit: mg/L
Current offshore platform process sanitary sewage has two kinds of methods.One is biochemical process, the microorganism in active sludge is utilized to degrade to the pollutent in sanitary sewage, but offshore platform is due to away from land, in order to save Freshwater resources, platform all uses seawater flushing lavatory, cause saltiness in sewage to increase, microorganism active is declined or inactivation, and the treatment effect of practical application mesophytization method to sanitary sewage is unsatisfactory.Another kind is electrolytic process, the sanitary sewage being mixed with seawater is carried out electrolysis, and the clorox (NaClO) of generation is Strong oxdiative sterilizing agent, can contact with the bacterium of sewage fully, by sterilization, reach the object removing pollutent, but in actual use, because in seawater, saltiness only has about 3%, electrolytic process can waste a large amount of electric energy, and electrolytic process is that the organic pollutant in sewage very easily causes electrode damage, reduction of service life by electrolysis after seawater and sanitary sewage mixing.
Summary of the invention
The object of the invention is to the shortcoming overcoming prior art, a kind of power-saving, offshore platform sewage treatment unit that long service life, treatment effect are good is provided.
A kind of offshore platform domestic sewage processing method of the present invention, it comprises the following steps:
(1) send into equalizing tank after kitchen drainage being removed oil slick by oil trap, mix with excrement and urine waste and other drainings in equalizing tank, then pump in sterilization pool by sewage output tube;
(2) after the seawater on less than 5 meters, sea is softening by softening installation, pump in brine tank, solid sodium chloride is added in brine tank, be mixed with after massfraction is greater than the strong brine of 20%, electrolyzer is pumped into by salt water delivery pipe, in electrolyzer, generate the sterilized water containing clorox, then sterilized water is pumped in sterilization pool;
(3) sewage and sterilized water mixing in sterilization pool, and use agitator rapid stirring, realize the elimination to bacterium in sewage, in sterilization pool, be provided with some groups of iron-carbon galvanic cells can produce ferrous ion and carbon granules simultaneously, while realization sterilization, passes through throwing out, remove the suspended contamination in sewage,, between galvanic cell, there is electrochemical oxidation decomposition reaction, change the organism of more easily degrading in the organic compound simultaneously in sewage;
(4) sewage after flocculation, sterilization flows in settling tank automatically, and after leaving standstill, supernatant liquid directly arranges sea after reaching emission standard; Lower floor's mud enters in plate-and-frame filter press, and the dewatered sludge obtained transports land process back, after pressing filtering liquid is qualified after testing, directly arranges sea, if defective, in pressing filtering liquid recycle pump suction sterilization pool, continues process, until again arrange sea after qualified.
The present invention compared with prior art, has the following advantages:
(1) by electrolysis after seawater salt adding, heighten electrolytic efficiency, while producing the sterilized water higher containing clorox (NaClO), save electric energy.
(2) sewage directly enters sterilization pool, only carries out electrolysis to high density salt solution, avoid the damage of the organism in sewage to electrode, improve the work-ing life of electrode at electrolyzer.
(3) iron-carbon galvanic cell is used, the ferrous ion produced and carbon granules, play throwing out to the suspended substance in sewage, the electrochemical energy simultaneously produced further promotes organic decomposition in sewage, and galvanic cell has advantages such as cost is low, long service life, usage space are little.
(4) mud is after pressure filter compacting mummification, transports land process back, no longer directly arranges sea, reduce further the pollution to ocean.
Accompanying drawing explanation
Fig. 1 is the schema of a kind of offshore platform domestic sewage processing method of the present invention.
Embodiment
Below in conjunction with Fig. 1 and specific embodiment, the present invention is described in detail:
Of the present invention a kind of offshore platform domestic sewage processing method as shown in Figure 1, it comprises the following steps: (1) sends into equalizing tank 7 after kitchen drainage is removed oil slick by oil trap 4, mix with excrement and urine waste and other drainings in equalizing tank, then pump in sterilization pool by sewage output tube; (2) after the seawater on less than 5 meters, sea is softening by softening installation, pump in brine tank 11, solid sodium chloride is added in brine tank, be mixed with after massfraction is greater than the strong brine of 20%, electrolyzer 14 is pumped into by salt water delivery pipe, in electrolyzer, generate the sterilized water containing clorox, then sterilized water is pumped in sterilization pool 17; (3) sewage and sterilized water mixing in sterilization pool, and with agitator 19 rapid stirring, realize the elimination to bacterium in sewage, some groups of iron-carbon galvanic cells are installed in sterilization pool simultaneously, ferrous ion and carbon granules can be produced, while realization sterilization, also by throwing out, remove the suspended contamination in sewage, the organic compound simultaneously in sewage, between galvanic cell, there is electrochemical oxidation decomposition reaction, change the organism of more easily degrading into; (4) sewage after flocculation, sterilization flows in settling tank automatically, and after leaving standstill, supernatant liquid directly arranges sea (COD≤300mg/L) after reaching emission standard; Lower floor's mud enters in plate-and-frame filter press 22, and the dewatered sludge obtained transports land process back, and pressing filtering liquid is qualified rear (COD≤300mg/L) after testing, directly row sea, if defective, in pressing filtering liquid recycle pump suction sterilization pool, continue process, until again arrange sea after qualified.
As the device realizing the inventive method, it comprises equalizing tank 7, and there are oil trap 4 and liquidometer 6 in inside, is imported by kitchen drainage 2 in oil trap 4, after removing oil slick, mixes, pump in sterilization pool 17 through sewage output tube 13 with excrement and urine waste and other drainings 1.Oil slick recovery port 5 and emergency overflow mouth 3 is offered in equalizing tank 7.
After seawater 9 is softening by softening installation 10, pump in brine tank 11, be provided with in brine tank 11 and throw salt mouth, add solid sodium chloride by throwing salt mouth 8, be mixed with after massfraction is greater than the dense salt solution of 20%, brine tank 11 is connected with electrolyzer 14 by salt water delivery pipe 12, electrolyzer 14 is connected by pipeline with sterilization pool 17, dense salt solution pumps into electrolyzer 14, generates the sterilized water containing clorox (NaClO), then pumped in sterilization pool 17 by sterilized water in electrolyzer 14.Electrolyzer 14 offers hydrogen discharge mouth 15, carries out voltage-regulation by electrolyzer control panel 16.
Sewage and sterilized water mixing in sterilization pool 17, and with agitator 19 rapid stirring, realize the elimination to bacterium in sewage, some groups of iron-carbon galvanic cells 18 are installed in sterilization pool 17 simultaneously, ferrous ion and carbon granules can be produced, remove the suspended contamination in sewage by throwing out.
Sewage after flocculation, sterilization flows in settling tank 20 automatically, and after leaving standstill 45min, the Sewage outlet 21 of supernatant liquid through being arranged on settling tank 20 top arranges sea; Lower floor's mud is through manually entering in plate-and-frame filter press 22, and the dewatered sludge obtained transports land process back, after pressing filtering liquid detection is qualified, directly sea is arranged, if defective, in pressing filtering liquid recycle pump 24 suction sterilization pool 17 through pressing filtering liquid discharge outlet 23, continue process, until again arrange sea after qualified.
Embodiment 1
(1) send into equalizing tank after kitchen drainage being removed oil slick by oil trap, mix with excrement and urine waste and other drainings in equalizing tank, then pass through sewage output tube with 1.5m3the flow of/h pumps in sterilization pool;
(2) after the seawater on less than 5 meters, sea is softening by softening installation, pump in brine tank, in brine tank, add solid sodium chloride, be mixed with after massfraction is greater than the strong brine of 20%, by salt water delivery pipe pump with 0.5m3the flow of/h pumps into electrolyzer, generates the sterilized water containing clorox, then pump in sterilization pool by sterilized water in electrolyzer;
(3) sewage and sterilized water mixing in sterilization pool, and use agitator rapid stirring, realize the elimination to bacterium in sewage, some groups of iron-carbon galvanic cells are installed in sterilization pool simultaneously, ferrous ion and carbon granules can be produced, while realization sterilization, also by throwing out, remove the suspended contamination in sewage, the organic compound simultaneously in sewage, between galvanic cell, there is electrochemical oxidation decomposition reaction, change the organism of more easily degrading into;
(4) sewage after flocculation, sterilization flows in settling tank automatically, and after 45min leaves standstill, supernatant liquid directly arranges sea after reaching emission standard; Lower floor's mud enters in plate-and-frame filter press, and the dewatered sludge obtained transports land process back, after pressing filtering liquid is qualified after testing, directly arranges sea, if defective, in pressing filtering liquid recycle pump suction sterilization pool, continues process, until again arrange sea after qualified.
The effect of employing present method is: the method is applied in certain offshore production platform, it is (70-125) mg/L that COD arranges extra large numerical value, meet the limit value of COD≤300mg/L in " offshore oil exploration and exploitation Pollutant emission concentration limit value " (GB4914-2008) completely, suspended substance is arranged extra large concentration and is less than 35mg/L, respond well.