Water treatment facility for recycling and decalcification of water in a car wash without drainage

DESCRIPTION

Water treatment facility to recycle and descale the water of a car wash, without spillages.

Field of the Invention

This invention relates to a water treatment facility suitable for recycling and decalcifying the water of a car wash, without spillages.

Background of the invention

The facilities for car washes, or car washes, in addition to high water consumption, about 200 liters of water per car wash or about 400 liters of water per car with low wash, generate a large amount of pollutants derived from Materials used to clean cars that, if not properly treated, constitute a potential source of environmental pollution.

To reduce water consumption in car washes, water recycling facilities have been planned, applied to a car wash, which allow a more or less significant amount of water to be reused. These facilities retain the dirt in the equipment itself although, after washing the equipment, the dirt is poured into the collector. As a result of all this, it is possible to reuse a greater or lesser amount of water, but the environment continues to be polluted and the cost of car washes increasing as wastewater treatment plants (WWTP) are needed.

With the entry into force in Spain of RD 484/95 of April 7, the Official Organizations require the installation of car washes that do not pollute the environment and declare it as abusive of the spill, with the sanctions provided in the Law for the ecological crime. Therefore, car washes that generate discharges, to comply with current regulations, must implement an installation for water recycling and ensure that the discharges generated comply, upon departure, with the provisions of the Water Law, because in case Otherwise, its discharge would not be authorized and the installation of a WWTP would be required.

Therefore, there is a need for an installation that allows the reuse of water consumed in a car wash that overcomes previously noted problems. This objective can be achieved through the design and development of an installation provided by this invention consisting of a water treatment facility suitable for recycling and decalcifying the water of a car wash, which does not generate spills (without spills), with that is achieved not only reduce water consumption but also avoid the installation of a WWTP, all of which favorably affects the environmental and economic aspects of laundry.

Brief description of the figures

Figure 1 shows a diagram of a water treatment facility for recycling and descaling the water of a car wash, without spills, provided by this invention. Detailed description of the invention

An adequate water treatment facility is provided to recycle and descale the water of a car wash, without spills. To facilitate the understanding of the nature of the present invention, the installation object of it was described with reference to the figure accompanying this report. As can be seen in Figure 1, said installation comprises:

- a purpose for receiving raw water (1);

- at least one intermediate tank (2);

- a primary conditioner (3);

- a secondary conditioner (4); Y

- a tertiary or refining conditioner (5).

The installation is completed with a sludge treatment equipment, a reagent dosing equipment, a laboratory equipment and an electrical equipment.

The deposit for the reception of the raw water (1) is a deposit suitable for collecting the raw water (9) from the car wash, in particular, from the cassette (8) for collecting water from the washing train. In this tank (1) the water (9) received is subjected to a process of decantation, precipitation and chemical flocculation through the use and dosage of the appropriate conventional reagents. The flocculated and clarified water (10) exits the upper part of said reservoir (1) and the sludge (11) is retained therein and extracted by any appropriate means, such as by means of an elóastic deformation membrane valve. The shape, dimensions and materials of the tank for the reception of the raw water (1) can vary depending on the needs and dimensions of the car wash. In a particular embodiment, said tank (1) is constructed with sheet steel.

The intermediate tank (2) collects the flocculated and clarified water (10) from the tank for receiving raw water (1) and serves to regulate the water level and to store the water necessary for water conditioners and to eliminate small traces of oils and fats, etc., that could leave the tank (1). The shape, dimensions and materials of the intermediate tank (2) can be variable. Sometimes a set of at least two intermediate deposits can be used. In a particular embodiment, the tank (2) is constructed with polyester.

The primary conditioner (3) is intended to eliminate suspended colloids from water, prevent the formation of microcontaminants and reduce water hardness to the desired values. For this, this conditioner (3) performs the functions of filtration-decalcification either separately or simultaneously. An example of said water conditioner (3) is a filter composed of a mixed bed of sand and cationic resin, such as that described in Spanish Patent No. P9402435. The use of a cationic resin allows to reduce the hardness of the water by ionic exchange to the desired level but without increasing the conductivity.

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The secondary conditioner (4) is intended to clarify the water from the primary conditioner (3). A water conditioner-oxygenator consisting of a filter consisting of a bed mixed with activated carbon that incorporates a Venturi, of the type described in Spanish patent application No. P9500152, can be used for this purpose.

The purpose of the tertiary or refining conditioner (5) is to eliminate all or part of the microcontaminants present in the water (15) from the secondary conditioner (4) and to correct the possible leaks of the previous equipment. The appropriate equipment for carrying out this treatment may have the same technical characteristics as the secondary conditioner (4). In a particular embodiment, the tertiary conditioner (5) is a mixture of the primary (3) and secondary (4) conditioners, and comprises a mixed bed of sand, active carbon and cationic resins. At the exit of the tertiary conditioner (5), the water recovers its characteristics and is sterilized by a suitable treatment, for example, with a solution of sodium hypochlorite.

The sludge (11) retained in the reservoir (1) is extracted and led to drying beds (6) constituted by a layer of siliceous sand extended on a gravel support.

To dose the reagents necessary for flocculation and sterilization of water, appropriate conventional metering pumps (7) can be used.

The laboratory equipment comprises a kit for measuring the hardness of water and a kit for determining chlorine and pH with their corresponding reagents, for example, orthotolidine and phenol red, for colorimetric determination. In addition, this equipment has a comparator case incorporated.

The electrical equipment is composed of a watertight control cabinet, differential relay, contactors, relays, level probes, timers, etc., in order to achieve a fully automated operation of the installation.

In general, the waste produced by the installation can be summarized as:

- discharges: null; Y

- sludge: mineralized are extracted.

Installation requires maintenance that depends on the number of cars washed and the time of year. In general, for a wash of 1,000 cars / month, maintenance operations are limited to washing the conditioners once a week. The time taken is approximately ten minutes. The rest of the teams work automatically. It is convenient to wash the installation manually. Likewise, it is convenient to carry out equipment washing operations when a large influx of cars is expected.

The invention also provides a method to recycle and decalcify the water of a car wash without waste that includes the use of the aforementioned installation.

As can be seen in Figure 1, the raw water (9), coming from the washing box (8) for collecting water from the washing train, is driven by a pump (21) to the tank (1) where it is subjected to a process of decantation, precipitation and chemical flocculation. The dosing of the reagents necessary for flocculation and sterilization of water is carried out by means of appropriate dosing pumps (7). The flocculated and clarified water (10) exits the top of the tank (1) and leads to the intermediate tanks (2) suitable for regulating the water level and for storing the water necessary for the conditioners (3), (4 ) and (5) of the water and to eliminate small traces of oils and fats, etc., from the tank (1). Degreased water (13) from the reservoirs (2) is driven by a pump to the primary conditioner (3) where it is subjected to a filtration process, descaling, together or separately, in order to eliminate suspended colloids, prevent formation of microcontaminants and reduce water hardness to desired values. Some of the water (14) from the primary conditioner (3) is recirculated to the cassette (8) while the rest feeds a secondary conditioner (4) where it is subjected to a clarification and oxygenation process. The outlet water (15) of the secondary conditioner (4) is distributed in two streams, one of which is recirculated to the cassette (8) while the other feeds a tertiary conditioner (5) where it is subjected to a refining process for remove all or part of the microcontaminants present in the water (15) from the secondary conditioner (4) and correct the possible leaks of the previous equipment. Water (16) from the tertiary conditioner (5) has regained its characteristics. Part of the water (16) is recirculated to the cassette (8) while the rest is sterilized by a suitable treatment, for example, by means of a solution of sodium hypochlorite of varying concentration, for example 160 grams of chlorine per liter, driven by a metering pump until a concentration of 1 ppm (part per million) is achieved. The treated water can be stored in a tank (20) before its departure (18) to the washing train when necessary. The tank (20) may also contain the wash water of the conditioners (3), (4) and (5). A part of the water (17) from the tank outlet (20) is used in the washing circuit of the conditioners (3), (4) and (5). The partial currents from the waters (14), (15) and (16) that are recirculated to the cassette (8) can be gathered in a single conduit (19).

The sludge (11) extracted automatically or manually by the lower part of the tank (1) is led to eras or drying beds (6) of sludge, where they are dried, mineralized and extracted manually or automaotically. The amount of sludge collected is a function of the number of washes (approximately 1 gram of sludge is generated per washed car). The thickness of the sludge on the bed must not exceed 35 cm. When the sludge (11) has become sufficiently compact, it is extracted with a shovel. The mud obtained does not produce a bad smell. Water (12) from sludge drying is recirculated to the cassette (8).

Through the installation provided by

In this invention, an "ecological laundry" is obtained, that is to say, a water recycling or reuse facility that, when applied to a car wash, has zero discharges since:

- most of the water used, both in car washes and equipment washes, returns to the same place where the water from car washes is poured, that is, to the case under the car wash , Y

- the sludge that is produced, after drying, is extracted mineralized.

<td colspan="3">Anions:</td>

<td></td><td>CO3H^-</td><td>200 ppm</td>

<td></td><td>CO₃^2-</td><td>100 ppm</td>

<td> 5</td><td>SW₄^2-</td><td>160 ppm</td>

<td></td><td>Total</td><td>460 ppm</td>

<td></td><td>Conductivity</td><td>1,801 microSie-</td>

<td rowspan="2"> 10</td><td></td><td>mens</td>

<td>Origin of the water</td><td>Municipal network</td>

<td></td><td>Temperature</td><td>24 ° C</td>

As a result, approximately 90-95% of the water used is recovered as ¹⁵only the one that evaporates and the small amount of water that cars take away is lost. Due to the absence of spills, no harmful effect on the environment is caused.

The following Example serves to illustrate a ²⁰particular form of a water treatment facility suitable for recycling and descaling the water of a car wash with zero discharge provided by this invention and should not be considered as limiting the supply of ²⁵Cancel of it.

Example 1

Design of an installation without spills

A water treatment facility designed to recycle and descale the water has been designed. ³⁰water from a car wash, without spills, taking into account the characteristics of the raw water, those of the water coming from the washing train and those of the washing train.

The measures expressed as ppm are equal ³⁵to parts per million, equal to milligram per liter or equal to gram per cubic meter.

one. Raw water characteristics

Solid Color Turbidity

TAF (Free strong acid content)

Chlorine

TH (Hydrothermal Grade) pH

two. Characteristics of water from the wash train &lt;30 ppm SiO2 &lt;20 ppm Pt mg / L

Negative

460 mg / L 8.32

TM (Magnesic hardness or hydrotyrometric degree mag-

<td>nóesico)</td><td>60 mg / L</td>

<td>TAC (alkalimetric grade</td><td></td>

<td>full)</td><td>280 mg / L</td>

<td>SAF (Global content in</td><td></td>

<td>strong acid salts)</td><td>120 mg / L</td>

<td>Faith</td><td>0.1 mg / L</td>

<td>Orgaonic Matter</td><td>2.1 mg / LO</td>

<td>Cations:</td><td></td>

<td>Ca2 +</td><td>300 ppm</td>

<td>_Mg²⁺</td><td>120 ppm</td>

<td>Na⁺</td><td>40 ppm</td>

<td>Total</td><td>460 ppm</td>

<td>pH</td><td> 5-10</td>

<td>Suspended solids</td><td>2,756 ppm</td>

<td>COD (Chemical demand of O2)</td><td>3,504 ppm</td>

<td>Oils and fats</td><td>926 ppm</td>

<td>Detergents (such as laurilsul- fatos [LAS])</td><td>224,400 ppm</td>

<td>Turbidity</td><td>2,600 ppm</td>

<td>BOD5 (Biological demand for standard O2)</td><td>230 ppm</td>

<td colspan="2">3. Characteristics of the washing train</td>

<td>Model</td><td>Automaotic</td>

<td>No. of units</td><td>A</td>

<td>Maximum washing capacity</td><td>60 units / ho-</td>

<td>Bass wash</td><td>ra Positive</td>

<td>Water consumption by car</td><td>200 L</td>

<td>Truck wash</td><td>Negative</td>

<td>Manual washing with pressure water shuttle</td><td>Positive</td>

<td>Water consumption by car with bass washing</td><td>400 L</td>

Based on the characteristics of the raw water, those of the water coming from the washing train and those of the washing train mentioned above, a suitable water treatment installation was designed to recycle and decalcify the water of a car wash with zero discharge that included The following equipment:

Deposit for receiving raw water (1)

Material

Volume

Dimensions

Sheet steel

14.25 m³

4,500 x 2,000 mm diameter

A defor membrane valve can be used for retention and removal of sludge₆₅ PIV elastic macioón (PIC-Dosapro Milton Roy).

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Intermediate Deposit (2)

Polyester Material

Volume 1,152 L

Dimensions 800 x 350 mm diameter

Number of deposits 2 of 576 L

Primary Conditioner (3)

Filter composed of a mixed bed of sand and a cationic resin, such as the one described in Spanish Patent No. P9402435, working in a closed circuit.

Characteristics:

<td>Model</td><td>CH-32</td>

<td>Maker</td><td>Applicant</td>

<td>Material</td><td>Sheet steel</td>

<td>Height</td><td>2,000 mm</td>

<td>Diameter Maximum working pressure</td><td>600 mm</td>

<td>low</td><td>5.1 x10⁵ bar (5 kg / cm²)</td>

<td>Pipe Diameter</td><td>3.81 cm (1.5 ”)</td>

<td>Number of valves</td><td>1 Hay-Ward Central</td>

<td>Gauge</td><td>0-5.1 x 10⁵ Pub</td>

<td>Regeneration NaCl consumption (per</td><td>Handbook</td>

<td>regeneration)</td><td>5 kg</td>

<td>Pump power</td><td>0.5 hp</td>

<td>Flow</td><td>12,000 L / h</td>

<td>Gauge height Interchange volume</td><td>20 m AC</td>

<td>ion bador</td><td>30 L</td>

<td>TH of treated water</td><td>mg / L at the preset value, between 2530 mg / L (Méax) and 0 mg / L</td>

Secondary conditioner (4)

Filter composed of a mixed bed of active carbon Hidrafin® (Bayer), with an absorption power between 950 and 1,050 m²/ g of total area (N₂ BET method), which incorporates a Venturi externally, such as that described in Spanish patent application No. P9500152.

Features:

Model CH-12 OXYGEN CONDITIONER

<td>015 A1</td><td> 8</td>

<td>Maker</td><td>Applicant</td>

<td>Material</td><td>Sheet steel</td>

<td>Total height</td><td>2,000 mm</td>

<td>Diameter</td><td>500 mm</td>

<td>Maximum working pressure</td><td></td>

<td>low</td><td>5.1 x 10⁵ Pub</td>

<td>Pipe Diameter</td><td>3.81 cm</td>

<td>Number of valves</td><td>1 Hay-Ward Central</td>

<td>Gauge</td><td>0-5.1 x 10⁵ Pub</td>

<td>Drive</td><td>Handbook</td>

<td>Control</td><td>Optical</td>

<td>Flow</td><td>12,000 L / h</td>

<td>Reclik-Oxi volume</td><td></td>

<td>gen-W</td><td>180 L</td>

<td colspan="2">Tertiary conditioner (5)</td>

<td>Mixed bed of</td><td>sand, active carbon Hi-</td>

<td colspan="2">drafin® (Bayer) and cationic resins, with characteristics similar to those of the secondary conditioner</td>

<td>dario (4).</td><td></td>

<td colspan="2">Sludge treatment</td>

<td>Number of units</td><td> 1</td>

<td>Dimensions</td><td>1,200 x 400 x 600 mm</td>

<td>Material</td><td>Sheet steel</td>

<td>Purges</td><td>Automatic</td>

<td>Drive</td><td>Timer</td>

<td colspan="2">Reagent dosing pumps</td>

<td>Model</td><td>DC-X-21</td>

<td>Maker</td><td>Dosapro Milton Roy</td>

<td>Number of heads</td><td> 2</td>

<td>Type</td><td>Pistoén in stainless steel</td>

<td>Warehouse Deposits</td><td></td>

<td>I lie</td><td> 2</td>

<td>Volume of each deposit-</td><td></td>

<td>located</td><td>125 L</td>

<td>Power</td><td>100 W</td>

<td>Tense</td><td>220 V monophasic</td>

For flocculation of water, ferric chloride is used as a flocculant, while for the sterilization of water seodic hypochlorite (160 g Chlorine / L) is used.

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