IT202100012224A1 - SURFACE TREATMENT UNIT FOR METALS, PARTICULARLY FOR STEEL - Google Patents

Description

DESCRIPTION of the industrial invention entitled:

?Unit? of surface treatment for metals, especially for steel?

DESCRIPTION TEXT

Field of invention

The present invention relates to the working of metals, in particular to the chemical surface treatments of steel.

Prior art and general technical problem

The chemical surface treatment cycle of steel generally includes degreasing, pickling, passivation, washing and rinsing with deionized water treatments, and presents non-negligible compatibility problems? environment, especially as regards waste disposal.

The execution of a treatment cycle of this type inside an industrial building requires that the building is originally equipped with a waste collection and disposal network, or that each processing station provides for an individual waste collection and a manual assignment of the same within the unit? of storage for the start of the final disposal. The units? of storage in question generally include storage tanks of polymeric material (e.g. PVC) which are subsequently sent for disposal in specialized centres.

The first solution presents an intrinsic constraint linked to the building: except for the possibility of a new construction, for which ? Is it possible to foresee the disposal network on a project basis, are the existing buildings not suitable? what if they don't have it? the construction of a network for the collection and disposal of wastewater deriving from the aforementioned steel treatment operations, primarily due to technical (e.g. excessive depth of the excavation and possible incompatibility with the characteristics of the existing structure) and economic constraints (very high intervention costs in relation to operating margins).

The second solution? affected by risks related to the handling and transfer of waste, and also poses significant risks related to the safety of the operator inside the building.

Purpose of the invention

The purpose of the present invention ? to solve the technical problems mentioned above. In particular, the purpose of the invention ? make the surface treatment of the steel through the use of chemical agents safe and with low environmental impact, facilitating the disposal of wastewater without requiring any arrangements for civil structures.

Summary of the invention

The purpose of the invention? reached by a? unit? of treatment having the characteristics forming the object of the following claims, which form an integral part of the technical teaching given here in relation to the invention.

Brief description of the figures

The invention will be now described with reference to the annexed figures, provided purely as a non-limiting example, in which:

- Figure 1 ? a schematic representation of a? unit? of treatment based on the invention,

- figure 2 ? a schematic representation of a control panel of the? unit? of treatment according to the invention

- figure 3 ? a perspective view of a preferred embodiment of the invention,

- figures 4 to 6 are perspective views with some components removed from the unit? of treatment of figure 3,

- figure 7 ? a side view with some components removed according to the arrow VII of figure 3,

- figure 8 ? a partial view corresponding to figure 1, but illustrating a further embodiment, and - figures 9 and 10 illustrate further advantageous aspects of the invention.

Detailed description

The reference number 1 in figure 1 indicates overall a unit? of surface treatment for metals according to the invention. The unit 1 ? configured to accommodate the surface treatment of metals subject to previous processing in order to eliminate residual oxides and impurities.

In various embodiments of the invention the unit? of treatment 1 includes:

- a containment structure 2

- a storage group 4 arranged inside the containment structure 2 and comprising one or more? tanks, each adapted to contain a liquid treatment agent,

- a dispensing unit 6 arranged inside the containment structure 2 and comprising at least one feed device configured for withdrawing a liquid treatment agent from one or more? corresponding tanks, and to send the liquid treatment agent to one or more? corresponding dispensing devices for the surface treatment of a metallic element, where the surface treatment is likely to generate one or more? liquid treatment products,

- a waste collection unit 8 arranged in the containment structure 2 and configured to receive the liquid treatment products, e

- at least one waste drainage unit 10 configured for withdrawing liquid treatment products from the waste collection unit 8 and for sending the liquid treatment products to a collection environment. Based on the invention, the collection environment can be an environment external to the containment structure 2, for example a storage tank external to the structure 2 (typically storage tanks of polymeric material to be delivered to specialized disposal centres) or a collection, post-treatment and recirculation environment inside the containment structure containment 2 (or, at most, even a single collection room inside structure 2).

The following description will present in detail the characteristics of the aforementioned elements.

With reference also to the figure The containment structure 2 ? preferably made as a container module (for example a container configured for use as a temporary housing module and/or for construction site) including a base 12, a plurality of side walls 14, 16, 18, 20 and a top wall 22 opposite the base 12 and spaced from it by the side walls 14, 16, 18, 20. According to the invention, and with particular reference to figure 1, the waste collection group 8 ? installed in the crankcase 12.

Preferably, the containment structure comprises a lattice frame of longitudinal metal profiles GL, transversal metal profiles GT, and vertical metal profiles GV assembled to define a three-dimensional lattice of parallelepiped or cubic shape whose meshes are closed by roll-up panels or curtains (or in general retractable) to define operating environments of the unit? of treatment 1. For the purpose, refer to the Cartesian axis system x-y-z reproduced in all the figures, which identifies the three directions in question (x = longitudinal; y = transversal; z = vertical).

The vertical development of the longitudinal GL and transversal metal profiles GT of the base 12 can conveniently be increased in order to allow a pi? easy housing of the waste collection unit 8 in the base itself.

In greater detail, the containment structure 2 comprises a partition 24 defining a technical compartment 26 and an operating compartment 28, in which the technical compartment 26 houses the storage unit 4 and the dispensing unit 6, and the operating compartment 28 houses the say one or more dispensing devices.

In the preferred embodiment of the figures, the side wall 14 is made in part by panels ? in correspondence with the portions pertaining to the technical compartment 26 ? and partly by means of a roll-up or retractable curtain at the pertinent portion of the operating compartment 28. The side wall 16 is preferably made entirely of panels ? both in correspondence with the technical compartment 26, and in correspondence with the operating compartment 28 in the opposite position to the portion of the wall 14 made by means of a roll-up or retractable curtain.

The side wall 18 ? also made with panels similar to those of the walls 14, 16, but ? provided with a door 30 to allow an operator?s access inside the technical compartment 26. With reference to figure 1, a further door 30? ? incorporated in the partition 24 so as to allow transit between the two rooms 26 and 28, without prejudice to the possibility to directly access the compartment 26 through the retractable or roll-up curtain which defines part of the wall 14.

Will I come now described the plant equipment?unit? of treatment 1 and in particular the preferred embodiments of the functional assemblies enumerated at the beginning of the present description will be detailed. Will the support for the description of the plant equipment be? provided primarily by figures 1 and 2, while figures 3 to 7 will show the location of the systems and components present in the diagram of figure 1 inside the containment structure in a preferred embodiment of the invention. The representation of figure 1 ? based on some graphic conventions for the representation of the plants, whose detail? provided below. The conventions obviously only concern the graphics relating to the systems, but do not strictly concern the reference numbers used in this description and the connection lines of the same.

Graphic conventions:

a) the solid line in the connections between components denotes a hydraulic line through which a liquid passes; it can? refer both to the transit of incoming liquids (such as water from the mains) and to the transit of wastewater. Is the line continuous? obviously also used to schematically represent portions of structures or components of the unit? of treatment 1, but the person skilled in the art will understand? how there? is absolutely normal in the context of a plant representation and has a different meaning than that intended for the representation of a plant;

b) the dotted line in the connections between components denotes a pneumatic line in which air or compressed air (or gas or compressed gas in general) passes;

c) the dotted line in the connections between components denotes an electric power supply line (including ? even if not expressly shown, also any signal lines);

d) where present, a continuous wavy line represents a rollable pipe or duct.

With reference to figure 1, the storage unit 4 comprises:

- a first tank S1, particularly a tank for a degreasing treatment agent,

- a second tank S2, particularly a tank for a pickling treatment agent,

- a third tank S3, particularly a tank for a passivating treatment agent,

- a fourth tank S4, particularly a tank for demineralised water.

In turn, the dispensing group 6 includes:

- a first pump P1 configured for drawing degreasing treatment agent from the first tank S1,

- a second pump P2 configured for drawing pickling treatment agent from the second tank S2, - a third pump P3 configured for drawing passivating treatment agent from the third tank S3, and

- a fourth pump P4 configured for drawing demineralised water from the fourth tank S4.

The pumps P1, P2, P3, P4 and the relative tanks S1, S2, S3, S4 are all located in the technical compartment 26 as can be seen from the diagram of figure 1 and from the representations of figures 4, 6. They are preferably made as pumps pneumatic (ie whose prime mover is a pneumatic motor incorporated in the pump itself) and are powered by a compressor C1 which is in turn driven by an electric motor MC1. The compressor C1 not only feeds the pumps P1-P4, but supplies compressed service air both in the technical compartment 26 and in the operating compartment 28: in this regard see the quick-fit terminals IR present in each of the rooms. On the delivery of the compressor C1 upstream of all the pneumatic utilities ? a FRL filter-pressure reducer-lubricator group is also arranged.

Each of the pumps P1-P4 (in particular their delivery) ? also hydraulically connected to a corresponding dispensing device L1 (pump P1), L2 (pump P2), L3 (pump P3), L4 (pump P4) installed in the operating compartment 28. The dispensing devices L1-L4 are preferably made as lances sprayers each configured for dispensing the treatment agent contained in the tank S1, S2, S3, S4 (depending on the lance) on the surface of a metal product to be treated in the operating compartment 28.

? also part of the dispensing unit 5 is a fifth pump P5 whose admission ? hydraulically connected to a W_IN hydraulic power interface of the unit? of treatment 1 by which ? is it possible to connect the unit? 1 to an external water supply. Along the hydraulic connection between the power supply interface W_IN ? preferably arranged a softener 32 (upstream of which a sand trap filter F1 is provided, while downstream of which a doser D1 is arranged) which is arranged. hydraulically connected in parallel a bypass line on which ? provided with a bypass valve 34. The pump P5, the softener 32, the valve 34, the filter F1 and the dispenser D1 are all installed in the technical compartment 26. The pump P5 ? therefore configured for drawing water from the water mains connected to the W_IN water supply interface and ? configured for sending a flow of water to a further dispensing device L5, preferably a dispensing lance connected by means of a quick coupling IR2 (here in coupled condition) to a retractable hose accumulated on a hose reel 36.

The W_IN interface also feeds a tap T38 which discharges into a sink or basin 38 located in the operating compartment 28 and intended for all the cleansing operations of the operator.

The crossing of the partition 24 by the hydraulic lines which from the dispensing group 4 lead to the dispensing devices L1-L5? made by wall pass fittings R1-R5, per s? notice. Identically, a wall pass fitting R38 allows the supply of the tap T38 in the operating compartment 28.

The waste collection unit 8 comprises a first collection tank 40 under a floor of the technical compartment 26 and a second collection tank 42 under a floor of said operating compartment 28. The floor ? advantageously achieved by means of a first grilled platform F26 in the technical compartment 26 above the tank 40 and a second grilled platform F28 in the operating compartment 28 above the tank 42.

In this regard, it should be noted that the tank 40 is generally made with constant dimensions, while the tank 42 preferably has a modular construction: in this way ? It is possible to make the containment structure 2 so as to provide the technical compartment 26 as a room with a fixed structure and dimensions (for example ? as preferred dimensions width(y)-length(x)-height(z) expressed in mm ? 2000 x 2000 x 2500), and the operating compartment 28 as a room with customizable structure and dimensions according to requirements (for example ? as preferred dimensions width(y)-length(x)-height(z) expressed in mm ? 2000 x 1500 x 2500 or 2000 x 2500 x 2500 or 2000 x 3500 x 2500 or more (e.g. 2000 x 8000 x 2500, 2000 x 10000 x 2500). It should also be noted that the containment structure 2 can? be made by providing different transversal dimensions for the compartments 26 and 28 (for example the compartment 28 can have a transversal dimension of 3000 mm and the technical compartment of 2000 mm), so that the compartments 26 and 28 can be assembled one to the other and the partition 24 ? effectively defined at the assembly interface of the two compartments.

In particular, the operating compartment 28 can? be made with different longitudinal developments in such a way as to offer a variable internal space according to the needs: in this sense, providing for a modular construction of the tank 42 (for example by means of single tank modules with an extension of 1 m in the direction of the GL profiles) favors a modular construction of the operating compartment 28.

The first collection tank 40 and the second collection tank 42 each comprise a discharge hydraulically connected to a drainage manifold 44, which flows outside the containment structure 2 at a hydraulic connection element, in particular a valve V8 . Does the wastewater drainage unit 10 include a recovery pump P6? driven by an electric motor MP6 - comprising an inlet hydraulically connected to the manifold 44 and configured to withdraw the liquid in the manifold 44 coming from the tanks 40 (spillage of liquids in the technical compartment, for example from pumps P1-P4), 42 (wastewater comprising liquid treatment products) and send them to a collection tank S5. Wastewater level in tank S5? monitored via a first level sensor LS1, or overflow sensor, and a second level sensor LS2, or alarm sensor in the tank. The LS1 sensor? configured to signal the achievement of a threshold level (too full) in tank S5, while sensor LS2 ? configured to signal the achievement of an overflow level of the S5 tank, which requires the activation of an alarm.

A third level sensor LS3 ? installed in tank 42 to signal the achievement of a threshold level (overflow) of wastewater in the tank itself. It should also be noted that for the waste collection group 8 ? Is it possible to provide a single collection tank to replace the tanks 40, 42 extending below the floor (grid platforms F26 and F28) of the technical compartment 26 and the operating compartment 28, and is it possible to provide? otherwise? It is possible to provide only the tank 42, possibly inserting the tanks S1-S4 in a double containment casing to avoid spills, and likewise the pumps P1-P4 in a containment casing (in the preferred embodiment shown these are installed without containment) .

In turn, the collection tank S5 comprises a discharge duct 46 which flows outside the containment structure at a hydraulic connection element, in particular a valve V5. The V5 valve, what? like the V8 valve ? a valve comprising an open position and a closed position, and functionally constitutes a discharge valve. In some embodiments, the S5 collection tank can serve as a removable collection environment inside the containment structure 2. In other words, can the liquid treatment products accumulated in the tanks 40, 42 and sent to the tank S5 remain inside the collection tank S5? which in this case will have? a sizing more? generous - up to the achievement of a threshold level which requires its extraction from the containment structure 2 and its transfer to a disposal centre.

In further embodiments, with reference to figure 8, the tank S5 can serve as a collection environment downstream of a DP wastewater post-treatment system (for example a lime purifier for industrial wastewater), i.e. a system configured for the purification of liquid treatment products fed by the P6 pump. In these embodiments, with reference to figure 8, the pump P6 collects the wastewater in the tanks 40 and/or 42 through the manifold 44 and sends it to the post-treatment system DP for its purification and subsequent reintroduction into circulation. In detail, the delivery of the P6 pump belongs to the DP post-treatment system, and the suction ports of a P6A pump (driven by an MP6A electric motor) and a P6B pump (driven by a electric MP6B). The P6A pump has a delivery in communication with the S5 tank, which in this case acts as a collection environment for the smaller fractions. heavy and/or more viscose of the wastewater/liquid treatment products taken from the manifold 44, while the pump P6B has a delivery in communication with a circuit node downstream of the delivery of the pump P5 for the reintroduction of demineralised water (resulting from the purification of the wastewater) into the water system of? unit? 1. In this way the S5 tank can? act as a unit of accumulation of sewage and pu? be emptied ? as needed? ? by removing it or by connecting an emptying pump to the V5 valve, and a part of the water flow rate required for feeding the L5 lance can? be provided by the purification of the wastewater itself. In these embodiments, ? Is it possible that the technical compartment 26 is made with larger dimensions than the exemplary ones (2000 x 2000 x 2500 mm) indicated above, this as a function of the capacity? of the S5 tank and/or the volume of the DP aftertreatment system and/or the space requirement of the additional equipment (e.g. P6A and P6B pumps).

According to an advantageous aspect of the invention, the wastewater drainage assembly 10 is whatever the function of the S5 tank - it includes an external emergency drain system. In particular, the collection tank S5 ? hydraulically connected to the admission of an emergency pump P7 (driven by an electric motor MP7) configured for taking the contents of the collection tank S5 and sending it outside the containment structure, in particular through a wall pass fitting RP7, where can? be conveniently provided with an emergency collection tank S6.

With reference again to figure 1 and figure 2, the unit? treatment unit 1 comprises an electrical supply interface V_IN configured for the electrical connection of the unit? of treatment to an external electrical network. The power supply interface? electrically and operatively connected to a control panel 48 configured for the distribution of the electric power supply to the delivery unit, to the wastewater drainage unit and in general to the electric users of the unit. of treatment 1. The V_IN interface? configured for power supply via a common 220V (single-phase) and 50 Hz alternating current electrical network, but multi-voltage and/or multi-current power supply solutions can be provided (for example 380 V three-phase), managing their adaptation to the characteristics of the users of? unit? of treatment 1 by means of the control panel 48 itself.

In particular, the control panel distributes power to the electric motor MC1 of compressor C1, to the electric motor M5 of pump P5, to the softener 32, to the motors MP6 and MP7 of pumps P6, P7, and to the level sensors LS1, LS2, LS3. Preferably, the panel 48 also distributes the electrical power to a motor M50 of an aspirator 50 of the operating compartment 28. The aspirator 50 can? advantageously be made by means of a device for controlled mechanical ventilation with heat recovery.

If additional electrical utilities are envisaged (for example electrical outlets of any kind) can these be controlled by means of the panel 48 or ? while taking the power supply from the interface V_IN ? aggregated to a different electrical backbone which also controls the lighting system inside the unit of treatment 1.

In some embodiments, with reference to figure 9, ? Is it possible to provide a semi-independent or completely independent power supply of the unit? of treatment 1 through the preparation of one or more? photovoltaic panels 52 on the top wall 22. The number and/or type of photovoltaic panels 52 determines the electrical power that can be supplied to the unit? of treatment 1 independently from the electric mains: in this way ? is it possible to adapt the? unit? 1 to numerous installation conditions, even making installation possible in environments without electrical systems.

With reference to figure 2, in a preferred embodiment the control panel 48 comprises a main switch I_GEN which selectively activates and deactivates the electric power supply to the aforementioned users. Some of the users are then associated with an individual switch on the control panel 48 combined with a warning light which signals the active power supply condition (green light; the associated user in brackets):

i) a switch I32 with relative light L32 for the softener 32

ii) an IP5 switch with relative LP5 indicator light for the MP5 motor of the P5 pump

iii) a switch IC1 with relative warning light LC1 for motor MC1 of compressor C1

iv) an IP6 switch with relative LP6 light for the MP6 motor of the P6 pump

v) an IP7 switch with relative LP7 light for the MP7 motor of the P7 pump

vi) a switch I50 with relative light L50 for the motor M50 of the aspirator 50.

In combination with the above, the control panel 48 can include an emergency stop button E and two indicator lights (red light) which indicate that the levels associated with sensors LS1 and LS2 have been reached in tank S5. A unit control electronics? also installed in the panel 48 for the automatic management of the users connected to it.

In other embodiments, the set of switches and indicator lights described above can be replaced by an automatic control (for example by PLC) and a? physical or virtual interface? such as a touch screen.

The functioning of the unit? of treatment 1 ? the following.

The unit 1 ? configured for the execution of a complete cycle of surface treatments on metallic elements ? for example of steel - inside it, in particular inside the operating compartment 28, without the release of slag outside and without need? of civil disposal infrastructures.

The unit 1 pu? be transported and set up in any industrial context or construction site, requiring only a water supply for the W_IN interface and an electrical supply for the V_IN interface. Are these two satisfied? elementary ? conditions, the unit? 1 pu? operate completely autonomously. This is a huge logistical advantage for the metal surface treatment industry, as the unit 1 pu? be installed in any industrial building even if it lacks the infrastructure normally required by this type of treatment as all the infrastructure in question? already incorporated in? unit? 1, enclosed in the containment structure 2. The availability? of a water connection and an electricity connection are almost taken for granted inside an industrial building (even for environments external to it such as a square) or a construction site, therefore the operational requirements of the unit? 1 are very small. It should also be noted that the containment structure 1 ? which can be equipped in such a way as to integrate devices that can typically only be found in industrial buildings, thus further reducing installation and commissioning requirements. With reference to figure 10, inside the containment structure can? be installed an overhead beam 54 with longitudinal orientation along which? a motorized hoist 56 is movable (the movement occurs in the longitudinal direction X56 ? ambiverse) with a vertically movable hook 58 (the movement occurs in the vertical direction Z58 ? ambiverse). On the hook 58 can be hung one or more? particulars to be subjected to pickling and immersion passivation, treatments that can be operated by means of a treatment tank 60 positioned below the beam 54 within the operating range of the hoist 56. This equipment can? be made optional and does not require changing the structure of the unit? 1 or the plant equipment of it already? described.

The operator who has to carry out the surface treatment cycle of a metallic element can? position the element in the operating compartment 28 and enter it through the door 30 or the roll-up or retractable curtain on the wall 14. By activating the general switch I_GEN and the individual switches of the utilities i)-vi) above, the dispensing unit 4 makes the treatment agents of the tanks S1-S4 are available to the lances L1-L4 by means of the pumps P1-P4 and the rinsing water to the lance L5 by means of the softener 32 and the pump P5. The operator can? perform the individual steps of the treatment ? degreasing (L1 lance), pickling (L2 lance), passivation (L3 lance), washing with demineralised water (L4 lance) and rinsing (L5 lance) ? simply using the L1-L5 lance associated with the treatment phase from time to time. The treatment agents dispensed by the L1-L5 lances mixed with the various impurities? (oxides, dirt, etc.) which are gradually eliminated from the surface of the metal element give rise to liquid treatment products which drain and collect in the tank 42 in the form of waste water crossing the grilled platform F28. It should be noted that any leaks from the tanks S1-S4 or spills from the pumps P1-P4 can collect with the same mechanism in the tank 40 crossing the grilled platform F26. Does the LS3 level sensor signal to the unit? control the achievement of the overflow level in the collection tank 42, causing the activation of the motor MP6 and of the pump 6. In this way the wastewater collected in the tank 42 is sent to the tank S5. The activation of the pump P6 likewise results in the withdrawal of the possible contents of the tank 40 and in the sending of the same to the tank S5.

When the overflow level is reached in tank S5, the corresponding warning light on panel 50 lights up and the operator can? proceed to drain the tank through valve V5. The download takes place with mode? entirely conventional in cubic or parallelepiped polymer containers which can be stored in any industrial site awaiting collection by a disposal service. If the S5 tank suddenly becomes close to overflowing due to a flow surplus sent by the P6 pump, the unit? control proceeds with the activation of the motor MP7 of the pump P7 to operate an emergency discharge in the collection tank S6. Throughout the treatment, the noxious vapors generated are extracted from the operating compartment 28 by the aspirator 50.

In the embodiments of the type object of figure 8, the tank S5 acts as a collection environment for the sewage resulting from the purification of the liquid treatment products through the post-treatment system DP: as mentioned, the pump P6 collects the waste in the tanks 40 and/or 42 through the manifold 44 and sends them to the post-treatment system DP for their purification and subsequent re-entry into circulation. The P6A pump takes the sewage from the DP post-treatment system pouring it into the S5 tank, while the P6B pump takes the liquid fraction leaving the DP after-treatment system ? essentially demineralized water? sending it back into circulation to feed the L5 lance.

A unit of treatment 1 such pu? even become independent from the connection to an external water network for certain periods of time, and ? if combined with the preparation of one or more? photovoltaic panels 52 ? also independent from the connection to an electrical supply network. Also not having the need? to dispose of the wastewater outside the containment structure 1 (the sewage remains in the tank S5 and the liquid fraction re-enters the circulation), a unit? 1 such can? also operate in hostile and/or lacking infrastructure environments? for example a construction site at high altitude or similar.

When the unit? of treatment 1 ? inactive, any residues on the bottom of the tanks 40, 42? not processable by the P6 pump due to their low head at the pump admission - they can be drained manually through the V8 valve.

The unit 1 therefore represents an integrated solution for the surface treatment of metal elements as it carries on board all the electrical, pneumatic and fluidic systems required inside the technical compartment, and all the treatment equipment in the operating compartment 28. unit? 1 also integrates? a real wastewater collection and disposal network created by the collection group 8 and the drainage group 10, which makes it ? as mentioned ? the installation possible in any industrial context in which an electric power supply and a water supply are available.

Naturally, the details of construction and the embodiments can be varied widely with respect to what has been described and illustrated, without thereby departing from the scope of the present invention as follows: as defined by the appended claims.