IT202100008417A1 - CHEMICAL-PHYSICAL BATCH TREATMENT PLANT FOR CIVIL OR INDUSTRIAL WASTEWATER AND RELATED PROCEDURE - Google Patents

Description

CHEMICAL-PHYSICAL BATCH TREATMENT PLANT FOR CIVIL OR INDUSTRIAL WASTE WATER AND RELATED PROCEDURE

TECHNICAL SECTOR

Object of the present invention ? a ?batch? of treatment and purification for civil or industrial waste water and the relative procedure implemented through the plant. In particular, said purification procedure ? particularly suitable for civil and industrial wastewater polluted by organic substances in contexts where it is not possible or ? particularly difficult to download wastewater in a sewer already? existing.

STATE OF ART

In the state of the art are the biological purification systems of waste water usually used when the polluting load of the water ? mainly organic in nature. Biological purification systems include systems that are particularly complex from a technological point of view and, in some cases, costly from an economic point of view. Biological purification essentially consists in making the waste water degrade by microorganisms in suitable environments in which the process can occur in the presence or absence of oxygen (aerobic or anaerobic processes). Therefore, biological purifiers essentially consist of systems in which a reaction between wastewater and a large mass of microorganisms takes place in various ways. One of the systems more widespread in the field of aerobic biological purification systems ? the activated sludge purification system which provides for a series of treatment phases including the most? important are: screening, sand removal and equalization, biological oxidation, sedimentation, disinfection. All these phases are associated with one or more? plants more or less complex.

TECHNICAL PROBLEM

The embodiments known to the state of the art are disadvantageous in that they are not particularly suitable for fields of application in which, for example, there is no? possibility? discharge of wastewater into a sewer already? existing (standalone) or for users characterized by a functionality? seasonal (summer or winter). For these fields of application, the biological purification systems known in the state of the art are particularly complex to implement from the technical point of view as well as disadvantageous from the economic point of view.

PURPOSE OF THE INVENTION

Therefore, the purpose of the invention? that of solving the drawbacks just mentioned by means of a batch plant (1) for the purification of civil or industrial waste water and relative purification process according to the technical characteristics set forth in the independent claim no. 1 and in the dependent claims as regards preferential or particularly advantageous aspects of the invention.

DESCRIPTION OF THE FIGURES

Figure 1 shows a scheme of a waste water purification plant, figure 2 shows a detailed view of the separation tank or reactor. DETAILED DESCRIPTION

With reference to the figures cited above, will it be described? in detail an example of preferential embodiment of the object of the present invention, which is wholly non-limiting.

How already? previously mentioned, object of the present invention ? a waste water treatment plant? a chemical-physical plant that works in batches (for small flow rates) or alternatively at a constant flow rate (for larger flow rates) and is a valid alternative to traditional biological purification systems.

Preferably, but not restrictively, the water purification plant and the related treatment process are particularly suitable for:

? unit? housing, recreational, tourist accommodation (hotels and restaurants), hospitals and nursing homes, prisons, etc. in which there is no possibility? discharge of wastewater into the municipal sewage system (stand-alone);

? tourist settlements (residences, villages/campsites, hotels) that have functionality? seasonal (summer or winter);

? community (towns or small cities?) with a strong tourist excursion to support the? existing system and meet the needs? of increased hydraulic and polluting load;

? industrial establishments where an effective purification and sterilization process of the process water is required;

? complexes, civil and industrial, in which there is waste and/or contaminated water to be treated in favor of reuse.

With reference to the diagram in figure 1, the waste water treatment plant (1) includes the following parts:

? a tank (VR) for accumulation or collection of waste water to be treated from users;

? a separation tank (2), called a reactor, in which a quantity is transferred? pre-established flow rate from the accumulation tank (VR); ? a reserve tank (VRIS) configured to accumulate a part of the water already? treated;

? pumping means (P1, P2, P3, P4) for the water inside the system; ? dosing means (D1, D2) for chemical products, preferably two dosing pumps, respectively for flocculant chemical product (D1) and for oxidizing chemical product (D2), for water treatment;

? electronic means for measuring the concentration of total suspended solids (T1, T2);

? a plurality? of level sensors (SL1, SL2, SLD1, SLD2) for signaling the minimum and maximum level for the aforementioned components.

? a plurality? of pipelines (C1, C2, C3, C4, C5, C6) between said components; ? water filtration and sterilization media (F1, F2)

an electronic control unit (CB)

Said dosing means (D1) and (D2) are provided with their own tanks for storing the chemical products, each provided with a minimum level probe, respectively (SLD1) and (SLD2).

With reference to figures 1 and 2, the valve (S1) for expelling the sludge, an electronic device (T2) for reading the solid concentration of the sludge at the outlet and a valve ( S4) for the inflow and outflow of the air inside the reactor (2). The sludge exit from the reactor takes place from a sludge outlet duct (21). At the bottom of the reactor (2) ? connected a pump (P3) to send a specific quantity? of purified water collected in the reserve tank (VRIS) through the pipe (C5) in the water inlet for sludge expulsion (22) of the reactor (2). Still at the bottom of the reactor, in correspondence with the recirculation duct (23) at the outlet, a valve (S2) and a pump (P2) are connected to the duct (C2) which intercept a three-way valve (S3) suitably configured for divert the clarified water towards the pipeline (C4) leaving the plant or to recirculate it at the top of the reactor through the pipeline C3.

In these terms, the pump (P2) on the pipeline (C2) can? act as a mixer pump, since ? configured to recirculate the wastewater being treated from the bottom of the reactor to the top of the same.

The clarified water in the pipeline (C4) first passes through a filter (F1) and then a UV sterilization system (F2) and is subsequently discharged into the treated waste line. A part of the treated water is accumulated in a reserve tank (VRIS) for the discharge of the sludge at the next cycle. Still at the bottom of the reactor, ? moreover, a drainage valve (DR1) is present which allows the tank to be emptied for a possible washing and/or emptying of the separation tank (2). There are also a valve (S5) and a washing pump (P4) configured to allow the execution of cleaning cycles of the system (1), optionally, by introducing clean water from an inlet auxiliary through the ducts (C6), (C4) and (C2) inside the reactor (2) in correspondence with the recirculation inlet (24). Alternatively, the washing pump (P4) can? be replaced by a valve. ? there is also an electronic control unit (CB) with PLC, to allow command, control and monitoring, possibly even remotely, of all the devices described above as well as all the level sensors present in the system (1). The control unit (CB) ? configured to operate in mode? of operation in automatic, or without request for intervention of any operator, or in modality? manual, which requires the presence of an operator to activate all the devices. The manual function is necessary, above all, in machine start-up and commissioning operations. The control unit (CB) ? equipped with at least one liquid crystal display, which shows all the operating information of the treatment cycle and all the reports of any faults and/or breakdowns. For these reports, both on-screen and acoustic warnings are also provided with the possibility sending them remotely by means of special outputs provided inside the electrical panel of the control unit (CB).

The reactor (2) ? consisting of an A316/A316L stainless steel tank, treated with a special paint coating to prevent corrosion. Alternatively, the material of the tub can be of the plastic type with the use of materials such as for example PP, PEHD, and others compatible with the chemical products used in the treatment process. The constituent parts of the system (1) can be assembled on a single stainless steel frame, of the standard type or customized according to the needs? and the spaces available on the installation site. The chemical products (or chemicals) used are basically of two types: a flocculant product and an oxidizing product, each dosed with a suitable quantity through the relative dosing pump (D1) and (D2) in the pipe (C3) through the recirculation inlet (24). Said oxidizing product, preferably ? made up of hydrogen peroxide. The chemicals are dosed simultaneously in the quantities? shown in the following table and with contact times better described in the procedure that will be described? afterwards:

The quantity? The dosage of each chemical product in the treatment phase depends on the load of the wastewater introduced into the reactor (2) in terms of Total Suspended Solids (TSS). The method implemented by the plant as just described is divided into the following phases and relative sub-phases, which, overall, reach a total duration of about 20 minutes.

The main stages of the procedure are as follows:

- (100) loading waste water into the plant

- (200) clarification of waste water in the reactor by means of the simultaneous dosing of an oxidizing product and a flocculant product and subsequent execution of alternating cycles of mixing and sedimentation - (300) expulsion of floating sludge

- (400) filtration, sterilization and discharge of treated water

- (500) cleaning of filtration systems

The waste water loading phase (100) involves carrying out the following steps inside the plant (1):

(110) filling the accumulation basin (VR) with waste water to be treated up to a maximum level (LR2)

(120) signaling that the maximum level has been reached (LR2) by means of a level sensor (SL2)

(130) transfer on input of the control unit (CB) of a pre-established quantity? of wastewater from the accumulation basin (VR) to the reactor (2) through the pipeline (C1) up to the level (L1) by means of a transfer pump (P1).

The waste water clarification phase (200) involves the following steps:

(210) activation of a mixer pump (P2) through the pipes (C2) and (C3) (220) reading of the quantity? of total suspended solids in the wastewater loaded into the reactor (2) using an electronic meter (T1)

(230) calculation of the quantity? of chemical products to be dosed by the control unit (CB) keeping the mixer pump active (P2)

(240) dosing of the flocculant product by means of the dosing pump (D1) in a range between 20 and 80 ml/l to be understood as milliliters of chemical product per liter of wastewater;

(250) dosing of the oxidizing product, preferably hydrogen peroxide, by means of a dosing pump (D2) in a range between 25 and 75 ml/l to be intended as milliliters of chemical product per liter of wastewater.

Subsequently, the control unit (CB) ? configured to process the following further phases, in which mixing and sedimentation cycles are performed alternately

(260) stop of the mixer pump (P2) for about 5 minutes;

(261) start of the mixer pump (P2) for about 0.5 minutes;

(262) stop of the mixer pump (P2) for about 5 minutes;

(263) start of the mixer pump (P2) for about 0.5 minutes;

(264) stop of the mixer pump (P2) for about 8 minutes.

At the end of this treatment phase, the Total Suspended Solids and part of the colloidal substances are completely flocculated, oxidized and separated from the treated water. Therefore, the next stage ? relating to the expulsion from the plant of such substances.

As regards the expulsion phase of the floating sludge (300), the following steps are envisaged:

(310) simultaneous opening of the valve (S1) and closing of the valve (S4) (320) starting of the pump (P3) for expelling sludge and introducing a specific quantity? of purified wastewater (or water) previously accumulated in the tank (VRIS) through the pipeline (C5);

(330) sludge expulsion from the reactor upon the occurrence of one of the following conditions: (331) starting or stopping of the pump (P3) for a predetermined time;

(332) stop of the pump (P3) upon reaching a pre-set limit value of the total suspended solids detected by an electronic measuring means (T2) for reading the total suspended solids of the outgoing sludge;

(333) start or stop of the pump (P3) by means of a level sensor (SL1), respectively at the maximum (LRIS2) and minimum (LRIS1) level

Before the final phase in the reactor (2) there are only the clarified waters without sludge already? expelled in the previous phase (300).

As regards the final stages of filtration, sterilization and discharge of the treated water (400), the following steps are envisaged:

(410) Diverting of the valve (S3) towards the pipes (C2) and (C4)

(420) Opening of the valve (S2) and starting of the mixer pump (P2) for a predetermined time

(430) Sending the clarified water to a filter (F1) and to a UV sterilization system (F2)

(440) sending a part of purified water to the reserve tank (VRIS) up to the maximum level (LRIS2)

(450) discharge of the remaining part of the purified water outside the plant (1).

Once a course of treatment is completed ?n? according to the sequence of phases just described, the plant (1) ? configured to proceed atomically with the start of a subsequent treatment cycle ?n+1? and what? away until the minimum level (LR1) is reached in the buffer tank (VR). Once this minimum level is reached, the plant stops and ? configured to restart automatically as soon as the maximum level (LR2) in the storage tank (VR) is restored.

? an optional cleaning phase (500) of the plant (1) is also envisaged which essentially consists in the activation of a certain predetermined number of treatment cycles of the backwash water of the filter (F1) loaded inside the reactor ( 2). The activation of the cleaning cycle? automatic and ? operated by the control unit (CB) which, at each generic cycle ?n?, counts the discharge time of the treated water and compares it with a preset maximum threshold value, beyond which, a certain predetermined number of water treatment cycles is activated backwash water starting from cycle ?n+1?. Once the backwash water treatment cycles have been completed, the plant (1) returns to normal operation of treatment of the waste water coming from the collection tank (VR). In particular, said cleaning cycle (500) ? divided into the following sub-phases: (510) Valve closing (S5) and valve opening (S2)

(520) Deviation of the valve (S3) in the direction of the pipes (C2) and (C4) (530) Starting of the washing pump (P4) and introduction of clean water inside the reactor (2) up to the level (L1)

(540) Implementation of steps (200) to (400) and related sub-steps

The number of backwash water treatment cycles ? pre-set in the control unit (CB) and modifiable according to need. Once the backwash water treatment cycles have ended, the plant (1) remains in operation and continues to treat the waste water accumulated in the basin (VR) until the minimum level is reached (LR1).

The wastewater treatment plant (1) can? be sized with different capacities? of treatment, in terms of cubic meters per day [m<3>/d], according to the need for treatment required at the site of use.

It is specified that the plant (1) ? very compact, light and versatile, available in different voltages, both in direct current and in single-phase or three-phase alternating current. The noise level? lower than 85 dB(A), thanks also to the use of suitable resilient elements mounted in the main pumping systems which significantly reduce their vibrations.

Clearly further developments are possible which can be brought by the expert in the field without thereby departing from the scope of the proposed invention.

Claims (13)

1. Civil and industrial waste water purification plant (1), comprising an accumulation tank for the waste water to be treated (VR), a reactor (2) configured to treat said waste water, a reserve tank (VRIS) configured to accumulate a part of the water already? treated before discharge, dosing means (D1, D2) of chemical products for water treatment, pumping means (P1, P2, P3, P4) for the water inside the system, means for shutting off the ?water (S1, S2, S3, S4, S5) inside the plant, a plurality? of pipes (C1, C2, C3, C4, C5, C6) which connect said components, at least one electronic control unit (CB) configured to operate said shut-off and pumping means, characterized in that said chemical product dosing means are configured to simultaneously dose at least one flocculant chemical product and at least one oxidizing chemical product in order to allow water purification; in that said flocculant chemical product ? dosed in a range between 20 and 80 ml/l to be understood as milliliters of chemical product per liter of wastewater and said oxidizing chemical product ? dosed in a range between 25 and 75 ml/l to be understood as milliliters of chemical product per liter of wastewater. and by the fact that said plant? configured to perform a purification process comprising the following stages: (100) loading wastewater into the reactor (200) waste water clarification by means of the simultaneous dosing of an oxidizing product and a flocculant product and subsequent execution of alternating mixing and sedimentation cycles (300) expulsion of floating sludge (400) filtration, sterilization and discharge of treated water (500) cleaning of filtration systems 2. Plant (1) according to claim 1 characterized in that said oxidizing chemical product is hydrogen peroxide. 3. Plant (1) according to claims 1 and 2 further comprising electronic means for measuring the concentration of total suspended solids (T1, T2), means for filtering and sterilizing the water (F1, F2). 4. Plant (1) according to claims from 1 to 3 characterized in that it is a plant of the batch type. 5. Waste water purification process configured for implementation in a waste water purification plant (1) according to claims 1 to 4 comprising the following main steps: (100) loading waste water into the plant (1) (200) treating waste water into the reactor (2) (300) expulsion of sludge deriving from water treatment (400) filtration, sterilization and discharge of treated water 6. Purification process according to claim 5 characterized in that said step of loading the waste water into the plant comprises the following steps: (110) filling the accumulation basin (VR) with waste water to be treated up to a maximum level (LR2) (120) signaling that the maximum level has been reached (LR2) by means of a level sensor (SL2) (130) transfer on input of the control unit (CB) of a pre-established quantity? of wastewater from the storage basin (VR) to the reactor (2) through the pipeline (C1) up to the level (L1) by means of a transfer pump (P1) 7. Purification process according to claim 5 characterized in that said waste water treatment step (200) comprises the following steps: (210) activation of a mixer pump (P2) through lines (C2) and (C3); (220) reading of the quantity? of total suspended solids in the waste water loaded inside the reactor (2) by means of an electronic meter (T1); (230) calculation of the quantity? of flocculant and oxidizing product to be dosed by the control unit (CB) keeping the mixer pump active (P2); (240) dosing of the flocculant product by means of a dosing pump (D1) in a range between 20 and 80 ml/l to be understood as milliliters of chemical product per liter of wastewater; (250) dosing of the oxidizing product, preferably hydrogen peroxide, by means of a dosing pump (D2) in a range between 25 and 75 ml/l to be intended as milliliters of chemical product per liter of wastewater. 8. Purification process according to claim 7 characterized in that said waste water treatment step (200) comprises the following further steps: (260) stop of the mixer pump (P2) for about 5 minutes; (261) start of the mixer pump (P2) for about 0.5 minutes; (262) stop of the mixer pump (P2) for about 5 minutes; (263) start of the mixer pump (P2) for about 0.5 minutes; (264) stop of the mixer pump (P2) for about 8 minutes. 9. Purification process according to claim 5 characterized in that said sludge expulsion step (300) comprises the following steps: (310) simultaneous opening of the valve (S1) and closing of the valve (S4) (320) start of the pump (P3) for expelling sludge and introducing a specific quantity? of purified water previously accumulated in the tank (VRIS) through the pipe (C5); (330) expulsion of sludge from the reactor. 10. Purification process according to claim 9 characterized in that said sludge expulsion step from the reactor (330)? configured to take effect when one of the following conditions occurs: (331) start or stop of the pump (P3) for a predetermined time; (332) stop of the pump (P3) upon reaching a pre-set limit value of the total suspended solids detected by an electronic measuring means (T2) for reading the total suspended solids of the outgoing sludge; (333) start or stop of the pump (P3) by means of a level sensor (SL1), respectively at the maximum (LRIS2) and minimum (LRIS1) level 11. Purification process according to claim 5 characterized in that said step of filtration, sterilization and discharge of the treated water (400) comprises the following steps: (410) Diverting of the valve (S3) towards the pipes (C2) and (C4) (420) Opening of the valve (S2) and starting of the mixer pump (P2) (430) Sending the clarified water to a filter (F1) and to a UV sterilization system (F2) (440) Sending a part of purified water to the reserve tank (VRIS) up to the maximum level (LRIS2) (450) Discharge of the remaining part of the purified water outside the system (1). 12. Purification process according to claims from 5 to 11 characterized in that said phases (100), (200), (300), (400) of the purification process are configured to repeat cyclically until the minimum level is reached (LR1 ) in the storage tank (VR) and restart automatically as soon as the maximum level (LR2) in the storage tank (VR) is restored. 13. Purification process according to claims 5 to 12 comprising a further cleaning step (500) of the plant comprising the following steps: (510) Closing of the valve (S5) and opening of the valve (S2) (520) Deviation of the valve (S3) in the direction of the pipelines (C2) and (C4) (530) Starting the washing pump (P4) and introducing clean water into the reactor (2) up to level (L1) (540) Implementation of steps (200) to (400)