CN104049565A - Method for controlling industrial wastewater level - Google Patents
Method for controlling industrial wastewater level Download PDFInfo
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- CN104049565A CN104049565A CN201410224549.9A CN201410224549A CN104049565A CN 104049565 A CN104049565 A CN 104049565A CN 201410224549 A CN201410224549 A CN 201410224549A CN 104049565 A CN104049565 A CN 104049565A
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- caustic soda
- storage barrel
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Abstract
The invention discloses a method for controlling the industrial wastewater level. The method for controlling the industrial wastewater level relates to an industrial wastewater treatment technology. The industrial wastewater treatment technology comprises the steps that industrial wastewater generated by each production line is collected into a reaction tank through a feed pump and a discharge pump, starting and stopping of the feed pump and starting and stopping of the discharge pump are controlled through a PLC, and the feed pump and the discharge pump are stopped under the control of the PLC when the level of industrial wastewater in the reaction tank reaches a preset value; a lower valve of a sulfuric acid storage tank is opened under the control of the PLC, and then sulfuric acid flows into the reaction tank from the sulfuric acid storage tank. The method can be applied to the industrial wastewater production technology. By the adoption of the method for controlling the industrial wastewater level, pollution to the environment can be effectively reduced, the whole treatment technology is achieved through automatic control of the PLC, the treatment efficiency can be effectively improved, and labor cost can be effectively reduced.
Description
Technical field
The present invention relates to industrial sewage production technology, especially a kind of industrial sewage liquid level controlling method.
Background technology
In prior art, industrial sewage refers to sewage, sewage and the waste liquid producing in industrial processes, wherein contains the pollutant producing in the commercial production materials, intermediate product and the product that outflow with water and production run.Along with developing rapidly of industry, kind and the quantity of sewage rapidly increase, and the pollution of water body, also increasingly extensively with serious, is threatened to the mankind's health and safety.Therefore,, for protection of the environment, the processing of industrial sewage is more even more important than the processing of municipal effluent.
At present, in the production run of industrial sewage, a lot of industrial sewages of unescapable generation always; Wherein, because high-tech sewage disposal device needs high expense and operating cost, cause the unable fund of bearing this respect of medium-sized and small enterprises, to wastewater treatment, also can only hang back.Many small enterprises, in self-growth, itself belong to a kind of extensive management mode, exchange economic increasing for exactly with sacrificialing environment.In whole sewage handling problem, impact and restraining factors maximum be the progress of sewage disposal technology technique.
Summary of the invention
The technical matters that the present invention solves is to provide a kind of industrial sewage liquid level controlling method, can effectively control the industrial sewage producing in corresponding industrial sewage level process.
For solving the problems of the technologies described above, the invention provides a kind of industrial sewage liquid level controlling method, it is characterized in that, by PLC, build sewage control network system, PLC is as slave computer, and its main work is the operational management of controlling whole equipment.Utilize the technology of bus communication to set up the above link of the next equipment, carry out omnidistance automatic control, greatly reduced the efficiency of whole wastewater treatment link, improve wastewater treatment efficiency and comprise industrial sewage treatment technology.Describedly comprise that industrial sewage treatment technology comprises: by feed pump and the unwatering pump arranging, the industrial sewage of each production line is collected in reaction tank, by the switching of the above-mentioned feed pump of PLC programmable logic controller (PLC) controls and unwatering pump, when the industrial sewage in reaction tank reaches preset height, PLC controls described feed pump and unwatering pump cuts out; PLC controls the lower valve of sulfuric acid storage barrel and opens, and sulfuric acid is flowed in reaction tank by storage barrel, and the mass percent concentration of described sulfuric acid is 28%; Meanwhile, PLC controls the stirrer startup stirring operation that is arranged on reaction tank; The pH value that the pH value sensor arranging in reaction tank detects in reaction tank sends to PLC, and when the detected value of pH value sensor is 5, PLC controls the lower valve of sulfuric acid storage barrel and closes;
PLC controls the lower valve of caustic soda storage barrel and opens, and caustic soda is flowed in reaction tank by storage barrel; The mass percent concentration of described caustic soda is 40%, and the ratio of the volume that adds the industrial sewage in volume and described reaction tank of described caustic soda is: 1:160; When the input amount that the flow sensor that is arranged on caustic soda storage barrel below detects caustic soda reaches predetermined value, described flow sensor sends the input amount signal that puts in place to PLC, and PLC controls the lower valve of caustic soda storage barrel and closes; When the lower valve shut-in time of caustic soda storage barrel being detected while being 2h, PLC controls the lower valve of catalyst stores bucket and opens, and when the volume of the addition of catalyzer and the addition of described caustic soda is 1:1, the lower valve of PLC control catalyst stores bucket is closed; When the lower valve shut-in time of catalyst stores bucket being detected while being 1h, PLC controls the stirrer that is arranged on reaction tank and stops stirring operation; When stirrer being detected and stop stirring operation 1h, PLC controls the flowing water Valve of reaction tank and opens, and the sewage in described reaction tank is got rid of outside reaction tank, closes above-mentioned flowing water Valve after emptying.
Technique scheme of the present invention has following beneficial effect:
The present invention can significantly reduce the industrial sewage content in sewage, can effectively reduce the pollution to environment; The whole treatment process of the present invention is crossed into by PLC and is automatically controlled realization, can effectively improve treatment effeciency, and can effectively reduce human cost.
Other features and advantages of the present invention will be set forth in the following description, and, partly from instructions, become apparent, or understand by implementing the present invention.Object of the present invention and other advantages can be realized and be obtained by specifically noted structure in instructions, claims.
Embodiment
For making the object, technical solutions and advantages of the present invention clearer, hereinafter will be elaborated to embodiments of the invention.It should be noted that, in the situation that not conflicting, the embodiment in the application and the feature in embodiment be combination in any mutually.
In industrial sewage, often contain bulk and strip foreign material that volume is larger, these foreign material are blocked when by barrier.The foreign material that are blocked, by special mechanical collection, compacting, are then transported to the special pond that holds, and after accumulating some, outward transport is processed.Sewage after this operation, through lift pump room, is promoted to eminence, makes the sewage subsequent handling of just flowing through voluntarily under Action of Gravity Field.In order to reduce the load of reaction tank, be provided with settling pit.Under lower flow velocity, the sand in sewage precipitates under Action of Gravity Field.Sewage after precipitation enters anaerobic pond, in anaerobic pond under the effect of mud and anaerobion, enters Aerobic Pond after sloughing most of phosphorus.Aerobic Pond is furnished with fan blower and stirring machine provides oxygen-enriched environment for aerobic bacteria wherein, under aerobic bacteria effect, further objectionable impurities is separated.Then enter secondary sedimentation tank, mud is precipitated, a part of mud is back to anaerobic pond through pump house, and remaining mud carries out thickening, processing with together with sand before.And sewage has now reached emission standard, can beyond row.
The invention provides a kind of industrial sewage liquid level controlling method, comprising:
By feed pump and the unwatering pump arranging, the industrial sewage of each production line is collected in reaction tank, by the switching of the above-mentioned feed pump of PLC programmable logic controller (PLC) controls and unwatering pump, when the industrial sewage in reaction tank reaches preset height, PLC controls described feed pump and unwatering pump cuts out;
PLC controls the lower valve of sulfuric acid storage barrel and opens, and sulfuric acid is flowed in reaction tank by storage barrel, and the mass percent concentration of described sulfuric acid is 25-28%; Meanwhile, PLC controls the stirrer startup stirring operation that is arranged on reaction tank; The pH value that the pH value sensor arranging in reaction tank detects in reaction tank sends to PLC, and when the detected value of pH value sensor is 4.5-5, PLC controls the lower valve of sulfuric acid storage barrel and closes;
PLC controls the lower valve of caustic soda storage barrel and opens, and caustic soda is flowed in reaction tank by storage barrel; The mass percent concentration of described caustic soda is 40-44%, and the ratio of the volume that adds the industrial sewage in volume and described reaction tank of described caustic soda is: 1:160 to 1:200; When the input amount that the flow sensor that is arranged on caustic soda storage barrel below detects caustic soda reaches predetermined value, described flow sensor sends the input amount signal that puts in place to PLC, and PLC controls the lower valve of caustic soda storage barrel and closes;
When the lower valve shut-in time of caustic soda storage barrel being detected while being 2h, PLC controls the lower valve of catalyst stores bucket and opens, when the volume of the addition of catalyzer and the addition of described caustic soda is 1:1 to 1:1.2, PLC controls the lower valve of catalyst stores bucket and closes;
When the lower valve shut-in time of catalyst stores bucket being detected while being 1h, PLC controls the stirrer that is arranged on reaction tank and stops stirring operation;
When stirrer being detected and stop stirring operation 1h, PLC controls the flowing water Valve of reaction tank and opens, and the sewage in described reaction tank is got rid of outside reaction tank, closes above-mentioned flowing water Valve after emptying;
PLC controls the feed pump and the unwatering pump that are connected with each production line and opens, and carries out the first step.
Accordingly, the invention provides following several embodiment and test accordingly structure:
Embodiment 1:
Step a:
By feed pump and the unwatering pump arranging, the industrial sewage of each production line is collected in reaction tank, by the switching of the above-mentioned feed pump of PLC programmable logic controller (PLC) controls and unwatering pump, when the industrial sewage in reaction tank reaches preset height, PLC controls described feed pump and unwatering pump cuts out; Unwatering pump is selected 45kW, and lift is 10m, and maximum flow is 500m
3h
-1conventional water pump, valve is selected the V-type electrically operated valve of DN250, control algolithm adopts PI closed-loop control.
Step b:
Set regulating reservoir liquid level, intelligent sensor is periodically converted into 4～20mA standard signal by the liquid level information collecting and sends in PLC controller, controller passes through PID controller action in the switch of control valve by the difference of setting value and measured value, and then change regulating reservoir aquifer yield regulates liquid level.If actual liquid level is greater than setting liquid level, controller can be sent valve opening signal automatically, and valve is opened to a certain degree again, if actual liquid level is less than setting liquid level, controller can be sent closing valve signal automatically, and valve is closed to a certain degree again.PLC controls the lower valve of sulfuric acid storage barrel and opens, and sulfuric acid is flowed in reaction tank by storage barrel, and the mass percent concentration of described sulfuric acid is 26%; Meanwhile, PLC controls the stirrer startup stirring operation that is arranged on reaction tank; The pH value that the pH value sensor arranging in reaction tank detects in reaction tank sends to PLC, and when the detected value of pH value sensor is 4.5, PLC controls the lower valve of sulfuric acid storage barrel and closes;
Step c:
PLC controls the lower valve of caustic soda storage barrel and opens, and caustic soda is flowed in reaction tank by storage barrel; The mass percent concentration of described caustic soda is 41%, and the ratio of the volume that adds the industrial sewage in volume and described reaction tank of described caustic soda is: 1:160; When the input amount that the flow sensor that is arranged on caustic soda storage barrel below detects caustic soda reaches predetermined value, described flow sensor sends the input amount signal that puts in place to PLC, and PLC controls the lower valve of caustic soda storage barrel and closes;
Steps d:
When the lower valve shut-in time of caustic soda storage barrel being detected while being 2h, PLC controls the lower valve of catalyst stores bucket and opens, when in the addition of catalyzer and described step c, the volume of the addition of caustic soda is 1:1, PLC controls the lower valve of catalyst stores bucket and closes;
Step e:
When stirrer being detected and stop stirring operation 1h, PLC controls the flowing water Valve of reaction tank and opens, and the sewage in described reaction tank is got rid of outside reaction tank, closes above-mentioned flowing water Valve after emptying;
By the discharge water in detection reaction pond, finally obtain a result as follows:
Industrial sewage content is 0.013%,
Content before processing with industrial sewage is compared, and reduces by 99.810%.
Embodiment 2:
Step a:
By feed pump and the unwatering pump arranging, the industrial sewage of each production line is collected in reaction tank, by the switching of the above-mentioned feed pump of PLC programmable logic controller (PLC) controls and unwatering pump, when the industrial sewage in reaction tank reaches preset height, PLC controls described feed pump and unwatering pump cuts out; Unwatering pump is selected 45kW, and lift is 10m, the conventional water pump that maximum flow is 500m3h-1, and valve is selected the V-type electrically operated valve of DN250, and control algolithm adopts PI closed-loop control
Step b:
After system starts, first manually set regulating reservoir liquid level, intelligent sensor is periodically converted into 4～20mA standard signal by the liquid level information collecting and sends in PLC controller, controller passes through PID controller action in the switch of control valve by the difference of setting value and measured value, and then change regulating reservoir aquifer yield regulates liquid level.If actual liquid level is greater than setting liquid level, controller can be sent valve opening signal automatically, and valve is opened to a certain degree again, if actual liquid level is less than setting liquid level, controller can be sent closing valve signal automatically, and valve is closed to a certain degree again.PLC controls the lower valve of sulfuric acid storage barrel and opens, and sulfuric acid is flowed in reaction tank by storage barrel, and the mass percent concentration of described sulfuric acid is 28%; Meanwhile, PLC controls the stirrer startup stirring operation that is arranged on reaction tank; The pH value that the pH value sensor arranging in reaction tank detects in reaction tank sends to PLC, and when the detected value of pH value sensor is 5, PLC controls the lower valve of sulfuric acid storage barrel and closes;
Step c:
PLC controls the lower valve of caustic soda storage barrel and opens, and caustic soda is flowed in reaction tank by storage barrel; The mass percent concentration of described caustic soda is 40%, and the ratio of the volume that adds the industrial sewage in volume and described reaction tank of described caustic soda is: 1:160; When the input amount that the flow sensor that is arranged on caustic soda storage barrel below detects caustic soda reaches predetermined value, described flow sensor sends the input amount signal that puts in place to PLC, and PLC controls the lower valve of caustic soda storage barrel and closes;
Steps d:
When the lower valve shut-in time of caustic soda storage barrel being detected while being 2h, PLC controls the lower valve of catalyst stores bucket and opens, when in the addition of catalyzer and described step c, the volume of the addition of caustic soda is 1:1, PLC controls the lower valve of catalyst stores bucket and closes;
Step e:
When stirrer being detected and stop stirring operation 1h, PLC controls the flowing water Valve of reaction tank and opens, and the sewage in described reaction tank is got rid of outside reaction tank, closes above-mentioned flowing water Valve after emptying.
By the discharge water in detection reaction pond, finally obtain a result as follows:
Industrial sewage content is 0.0083%,
Content before processing with industrial sewage is compared, and reduces by 99.870%.
Above-mentioned industrial sewage liquid level controlling method provided by the invention, compares with the treatment process of relevant art, has following beneficial features:
1, the industrial sewage content in the sewage in industrial sewage production run significantly, can effectively reduce the pollution to environment.
2, whole treatment process is crossed into by PLC and is automatically controlled realization, can effectively reduce human cost.
Although it is apparent to those skilled in the art that the disclosed embodiment of the present invention as above, the embodiment that described content only adopts for ease of understanding the present invention, not in order to limit the present invention.Those of skill in the art under any the present invention; do not departing under the prerequisite of the disclosed spirit and scope of the present invention; can in the form of implementing and details, carry out any modification and variation; but scope of patent protection of the present invention, still must be as the criterion with the scope that appending claims was defined.
Claims (1)
1. an industrial sewage liquid level controlling method, it is characterized in that, comprise industrial sewage treatment technology, describedly comprise that industrial sewage treatment technology comprises: by feed pump and the unwatering pump arranging, the industrial sewage of each production line is collected in reaction tank, by the switching of the above-mentioned feed pump of PLC programmable logic controller (PLC) controls and unwatering pump, when the industrial sewage in reaction tank reaches preset height, PLC controls described feed pump and unwatering pump cuts out; PLC controls the lower valve of sulfuric acid storage barrel and opens, and sulfuric acid is flowed in reaction tank by storage barrel, and the mass percent concentration of described sulfuric acid is 28%; Meanwhile, PLC controls the stirrer startup stirring operation that is arranged on reaction tank; The pH value that the pH value sensor arranging in reaction tank detects in reaction tank sends to PLC, and when the detected value of pH value sensor is 5, PLC controls the lower valve of sulfuric acid storage barrel and closes; Wherein, unwatering pump is selected 45kW, and lift is 10m, and maximum flow is 500m
3h
-1conventional water pump, valve is selected the V-type electrically operated valve of DN250, control algolithm adopts PI closed-loop control.Set regulating reservoir liquid level, intelligent sensor is periodically converted into 4～20mA standard signal by the liquid level information collecting and sends in PLC controller, controller passes through PID controller action in the switch of control valve by the difference of setting value and measured value, and then change regulating reservoir aquifer yield regulates liquid level.If actual liquid level is greater than setting liquid level, controller can be sent valve opening signal automatically, and valve is opened to a certain degree again, if actual liquid level is less than setting liquid level, controller can be sent closing valve signal automatically, and valve is closed to a certain degree again.
PLC controls the lower valve of caustic soda storage barrel and opens, and caustic soda is flowed in reaction tank by storage barrel; The mass percent concentration of described caustic soda is 40%, and the ratio of the volume that adds the industrial sewage in volume and described reaction tank of described caustic soda is: 1:160; When the input amount that the flow sensor that is arranged on caustic soda storage barrel below detects caustic soda reaches predetermined value, described flow sensor sends the input amount signal that puts in place to PLC, and PLC controls the lower valve of caustic soda storage barrel and closes; When the lower valve shut-in time of caustic soda storage barrel being detected while being 2h, PLC controls the lower valve of catalyst stores bucket and opens, and when the volume of the addition of catalyzer and the addition of described caustic soda is 1:1, the lower valve of PLC control catalyst stores bucket is closed; When the lower valve shut-in time of catalyst stores bucket being detected while being 1h, PLC controls the stirrer that is arranged on reaction tank and stops stirring operation; When stirrer being detected and stop stirring operation 1h, PLC controls the flowing water Valve of reaction tank and opens, and the sewage in described reaction tank is got rid of outside reaction tank, closes above-mentioned flowing water Valve after emptying.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410224549.9A CN104049565A (en) | 2014-05-26 | 2014-05-26 | Method for controlling industrial wastewater level |
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| CN201410224549.9A CN104049565A (en) | 2014-05-26 | 2014-05-26 | Method for controlling industrial wastewater level |
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2014
- 2014-05-26 CN CN201410224549.9A patent/CN104049565A/en active Pending
Patent Citations (8)
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|---|---|---|---|---|
| CN1331054A (en) * | 2000-06-29 | 2002-01-16 | 上海理日申能环境工程有限公司 | Intermittent automatic process and equipment for treating waste water |
| CN1569698A (en) * | 2004-05-12 | 2005-01-26 | 东华大学 | Method and equipment for treatment of polluted fluid |
| DE102005014233A1 (en) * | 2005-03-30 | 2006-04-06 | Daimlerchrysler Ag | Automated production line operating method, involves controlling high-speed retaining function of production line by using software, where access to function takes place by control unit, which is provided in line |
| US20060283787A1 (en) * | 2005-06-20 | 2006-12-21 | Pedee Vincent J C | Integrated Advanced Simultaneous Oxidation Process (ASOP) to Defeat Chemical, Biological, and Radiological Agents in Aqueous and/or other Fluid Solutions |
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Application publication date: 20140917 |
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