Method and system for detecting and controlling the input and residual concentration of a hard surface cleaner and a rinsing aid in an automotive parts washer

Abstract

The present disclosure relates to a method and system for detecting and controlling the input and residual concentration of a hard surface cleaner and a rinsing aid in an automotive parts washer. In particular, the method and system are particularly suitable for a cleaning system employed prior to the painting of exterior plastic parts. The method and system include a UV meter (302), a controller (306), and a metering pump (310), and the controller is in electrical communication with the UV meter and the metering pump.

Description

【Technical Field】 【0001】 (Cross - Reference to Related Applications) This application claims the benefit of U.S. Provisional Patent Application No. 63 / 368,544, filed on Jul. 15, 2022, under 35 U.S.C. § 119(e), the entire content of which is incorporated herein by reference. 【0002】 (Field of the Invention) The present disclosure relates to methods and systems for detecting and controlling the dosing and residual concentration of hard - surface cleaners and rinsing aids in automotive part washers. In particular, the methods and systems are particularly suitable for cleaning systems employed prior to the painting of exterior plastic parts. 【Background Art】 【0003】 After the manufacture of automotive parts, exterior plastic parts and automotive fascias must be thoroughly cleaned and rinsed before painting by the manufacturer. Cleaning systems typically have multiple stages, and the plastic passes through at least a cleaning stage where the wash water contains a detergent and a subsequent rinsing stage. In some cleaning systems, there are multiple cleaning and / or rinsing stages. During the process, wash water and rinse water are typically sprayed at each stage and collected in a drain for reuse. The detergent concentration in the reused wash water is often affected by (1) residual detergent on the product (which enters the rinsing stage), (2) dirt washed away and captured in the reused wash water, and (3) losses of wash water due to splashing and spraying beyond the drain carried through the parts. For this reason, the wash water must be continuously and periodically tested for the appropriate detergent concentration associated with one or more wash chambers. The current process for testing wash water is by titration, and then the detergent concentration is manually adjusted. This is time - consuming, labor - intensive, and may require adjusting the cleaning system multiple times a day. 【Summary of the Invention】 【Problems to be Solved by the Invention】 【0004】 Accordingly, an object of the present disclosure is to provide an alternative method and system for testing the detergent concentration in wash water. 【0005】 A further object of the present disclosure is to provide an alternative method and system for adjusting the detergent concentration in wash water. 【0006】 Yet another object of the present disclosure is to reduce the downtime of a washing system for testing and correcting the detergent concentration in wash water. 【0007】 Yet another object of the present disclosure is to improve the operation of a washing system by maintaining a desired residual detergent concentration in wash water. 【0008】 Other objects, advantages and features of the present disclosure will become apparent from the following specification in conjunction with the accompanying drawings. 【Means for Solving the Problems】 【0009】 A preferred embodiment is a plastic automotive part and fascia washing system comprising a washing stage with a conveyor belt, a sprayer, and a drain, a metering pump, a sensor, and a controller, the sprayer being configured to spray water and / or water containing detergent, the drain having an inlet to a recovered wash water container, the conveyor being configured to convey plastic automotive parts and / or fascia, the metering pump being configured to discharge detergent into a mass of water and / or recovered wash water, the sensor including a UV meter, the sensor being configured to perform a UV transmittance measurement of the recovered wash water, the controller being in electrical communication with the sensor and the metering pump, the controller storing a calibration plot of UV transmittance versus the concentration of surfactant species in the detergent, the calibration plot including a set point. 【0010】 A preferred embodiment is a kit for modifying a plastic automotive part and a fascia cleaning system, comprising a sensor, a metering pump, and a controller comprising a transmitter and a receiver for electrically communicating with the sensor and the metering pump, the sensor including a UV meter, the controller storing a calibration plot of UV transmittance or absorbance versus the concentration of surfactant species in the detergent, the calibration plot including a set point. 【0011】 A preferred embodiment is a method of cleaning a plastic automotive part and / or fascia, the method comprising placing the plastic automotive part and / or fascia on a conveyor, operating the conveyor through one or more cleaning stages of a cleaning system, spraying cleaning water containing a detergent containing a surfactant onto the plastic automotive part and / or fascia at one or more cleaning stages of the cleaning system, recovering the cleaning water from one or more cleaning stages after spraying, sensing the UV transmittance or absorbance of the surfactant in the recovered cleaning water via a sensor, comparing the UV transmittance of the recovered cleaning water with the set point on the calibration plot, adding water or detergent to the recovered cleaning water, wherein the amount of water and / or detergent is determined by the difference between the measured UV transmittance or absorbance and the set point on the calibration plot, and recirculating the recovered cleaning water with water or detergent added back into the cleaning system. 【0012】 While multiple embodiments are disclosed, still other embodiments of the invention will be apparent to those skilled in the art from the following detailed description which illustrates and describes exemplary embodiments of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. 【Brief Description of the Drawings】 【0013】 【Figure 1】 An example of a cleaning system for automotive plastic parts and fascia is illustrated. 【0014】 【Figure 2A】 An embodiment of a four-stage cleaning system is illustrated. 【0015】 【Figure 2B】 In accordance with at least some aspects of the present disclosure, the cleaning system of FIG. 2A is beneficially modified. 【0016】 【Figure 3A】 A graph of conductivity based on the concentration of the cleaning detergent in RO water (by weight %). 【0017】 【Figure 3B】 A graph of ultraviolet (UV) transmittance at 254 nm based on the concentration of the cleaning detergent in RO water corresponding to FIG. 3A. 【0018】 【Figure 3C】 Plot the calibration of the conductivity of the cleaning water based on the concentration of the cleaning detergent in RO water (by weight %). 【0019】 【Figure 3D】 Plot the calibration of the ultraviolet (UV) transmittance at 254 nm based on the concentration of the cleaning detergent in RO water corresponding to FIGS. 3A - 3C. 【0020】 【Figure 4A】 Analyze the conductivity of the cleaning water containing the detergent through various cleaning stages in comparison with RO and tap water without detergent. FIG. 4A is based on the comparison of the tap water employed in FIGS. 3A - 3D. 【0021】 【Figure 4B】 Compare the conductivity of the cleaning water containing the detergent at various cleaning stages with the actual concentration of the detergent in the cleaning water. FIG. 4B is based on the comparison of RO and tap water employed in FIGS. 3A - 3D. 【0022】 【Figure 5A】 Plot the calibration of the conductivity of the cleaning water based on the concentration of the cleaning detergent in tap water (by weight %). 【0023】 【Figure 5B】 A graph showing the ultraviolet (UV) transmittance at 254 nm based on the concentration of the cleaning detergent in tap water corresponding to Fig. 5A. 【0024】 【Figure 5C】 The calibration of the ultraviolet (UV) transmittance at 254 nm based on the concentration of the cleaning detergent in tap water corresponding to Figs. 5A to 5B is plotted. 【0025】 【Figure 6A】 The conductivity of the cleaning water containing the detergent is analyzed through various cleaning stages and compared with tap water not containing the detergent. Fig. 6A is based on the comparison of the tap water used in Figs. 5A to 5C. 【0026】 【Figure 6B】 The conductivity of the cleaning water containing the detergent at various cleaning stages is compared with the actual concentration of the detergent in the cleaning water. Fig. 6B is based on the comparison of the tap water used in Figs. 5A to 5C. 【0027】 【Figure 7A】 A graph of the ultraviolet (UV) transmittance at 254 nm based on the concentration of the cleaning detergent in tap water, comparing the transmission data of three separate sample sets from different geographical locations (including two separate different cities and one reverse osmosis water). 【0028】 【Figure 7B】 The measured values of the ultraviolet (UV) transmittance at 254 nm based on the concentration of the cleaning detergent in tap water, comparing the transmission data of three separate sample sets from different geographical locations (including two separate different cities and one reverse osmosis water). 【0029】 【Figure 8A】 A graph of the conductivity based on the concentration (by weight) of the cleaning detergent in tap water. 【0030】 【Figure 8B】 It is a graph of the ultraviolet (UV) transmittance at 254 nm based on the concentration of the cleaning detergent in tap water corresponding to FIG. 8A. 【0031】 【Figure 8C】 Using RealTech UV 254 UVT, plot the calibration of the ultraviolet (UV) transmittance at 254 nm based on the concentration of the cleaning detergent in tap water corresponding to FIGS. 8A to 8B. 【0032】 【Figure 8D】 Using Hach DR-6000, plot the calibration of the ultraviolet (UV) transmittance percentage at 254 nm based on the concentration of the cleaning detergent in tap water corresponding to FIGS. 8A to 8B. 【0033】 【Figure 9A】 It is a graph of the conductivity based on the concentration (by weight) of the cleaning detergent in RO water. 【0034】 【Figure 9B】 It is a graph of the ultraviolet (UV) absorbance at 254 nm based on the concentration of the cleaning detergent in RO water corresponding to FIG. 8A. 【0035】 【Figure 9C】 Using RealTech UV 254 UVT, plot the calibration of the ultraviolet (UV) transmittance at 254 nm based on the concentration of the cleaning detergent in RO water corresponding to FIGS. 9A to 9B. 【0036】 【Figure 9D】 Using Hach DR-6000, plot the calibration of the ultraviolet (UV) transmittance at 254 nm based on the concentration of the cleaning detergent in RO water corresponding to FIGS. 9A to 9B. 【0037】 【Figure 10】 Compare the transmittance, absorbance, and conductivity of the cleaning water at different cleaning machine stages. 【0038】 Various embodiments of the preferred embodiments are described in detail with reference to the figures, and like reference numerals represent like parts throughout the several figures. References to various embodiments do not limit the scope of the invention disclosed herein. The figures presented herein are not intended to limit the various embodiments of the invention disclosed, but are presented for illustrative example of the invention. 【Mode for Carrying Out the Invention】 【0039】 In the following detailed description, reference is made to the accompanying drawings which form a part hereof. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized and other changes may be made without departing from the spirit or scope of the subject matter presented herein. 【0040】 The present disclosure relates to a method and system for testing the cleaning water of an automotive parts cleaning system, and a method and system for adjusting the detergent concentration in the cleaning water of an automotive parts cleaning system. The present system and method have many advantages over conventional and existing systems and methods for testing and adjusting the cleaning water in an automotive parts cleaning system. An advantage of the present disclosure is that it provides a more rapid test of the cleaning water. Yet another advantage is that the test method can be automated, reducing the need for manual testing. Still another advantage of the present disclosure is that the test method can be integrated into the adjustment of the detergent concentration such that an automated system can test the cleaning water and automatically adjust the detergent concentration. Another advantage of the present disclosure is that the method and system can reduce the downtime of the cleaning system. 【0041】 Embodiments of the present disclosure can be modified and are not limited to specific automotive part cleaning systems (including those with more or fewer stages) understood by those skilled in the art. Further, it should be understood that all technical terms used herein are for the sole purpose of describing specific embodiments and are not intended to limit in any manner or scope. For example, as used in this specification and the appended claims, the singular forms "a", "an", and "the" may include plural referents unless the context clearly dictates otherwise. Further, all units, prefixes, and symbols may be expressed in the form recognized by their SI. 【0042】 Numerical ranges recited within this specification include the numbers defining the range and include each integer within the defined range. Throughout the present disclosure, various aspects of the preferred embodiments are presented in range format. The description in range format is for convenience and brevity only and should not be construed as a rigid limitation on the scope of the invention. Accordingly, the recitation of a range should be considered to specifically disclose all possible sub-ranges, fractions, and individual numerical values within that range. For example, a description of a range such as 1 - 6 should be considered to specifically disclose sub-ranges within that range such as 1 - 3, 1 - 4, 1 - 5, 2 - 4, 2 - 6, 3 - 6, as well as the individual numbers, e.g., 1, 2, 3, 4, 5, and 6, and decimal and fractional numbers, e.g., 1.2, 3.8, 1 and 1 / 2, and 4 and 3 / 4. This applies regardless of the width of the range. 【0043】 To make the present invention more easily understandable, certain terms will first be defined. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which embodiments of the present invention pertain. Many methods and materials similar to, modified from, or equivalent to those described herein can be used in the practice of embodiments of the present invention without undue experimentation, and preferred materials and methods are described herein. In describing and claiming embodiments of the present invention, the following specialized terms will be used according to the definitions set forth below. 【0044】 As used herein, the term "about" refers to any quantifiable variable, including but not limited to concentration, mass, volume, time, temperature, wavelength, pH, etc., and refers to variations in quantities that may occur through typical measurement techniques and equipment. Further, considering the handling procedures of solids and liquids used in the real world, there are certain inadvertent errors and variations that can occur through differences in the manufacture, source, or purity of the components used, for example, in making a composition or performing a method. The term "about" also encompasses amounts resulting from different equilibrium conditions for a composition arising from a particular initial mixture. The term "about" also encompasses these variations. Whether or not modified by the term "about", the claims include equivalents to that amount. 【0045】 The terms "actives" or "percent actives" or "percent by weight actives" or "actives concentration" are used interchangeably herein and refer to the concentration expressed as a percentage of those components involved in a wash after subtracting inert components such as water or salts. 【0046】 "Anti-redeposition agent" refers to a compound that helps to remain suspended in water instead of redepositing on the object being cleaned. The anti-redeposition agent is useful in the present invention to assist in reducing the redeposition of the removed dirt on the surface being cleaned. 【0047】 As used herein, the term "cleaning" refers to a method used to promote or assist in dirt removal, bleaching, reduction of the microbial population, and any combination thereof. As used herein, the term "microorganism" refers to any acellular or unicellular (including colonies) organism. Microorganisms include all prokaryotes. Microorganisms include bacteria (including cyanobacteria), spores, lichens, fungi, protozoa, virinos, viroids, viruses, phages, and some algae. As used herein, the term "microbe" is synonymous with "microorganism". 【0048】 The term "hard surface" refers to a substantially non-flexible surface of a solid, such as automotive parts including parts of passenger cars, trucks, ATVs, tractors, boats and the like. Hard surface parts can include, for example, doors, fenders, handles, panels including exterior panels, roofs, trims, etc. Examples of hard surfaces can include, for example, healthcare surfaces and food processing surfaces, manufacturing equipment, parts, belts, conveyors, appliances, countertops, tiles, floors, walls, panels, windows, faucets, kitchen and bathroom fixtures, electrical appliances, engines, circuit boards, and tableware. 【0049】 As used herein, the term "polymer" generally includes, but is not limited to, homopolymers, copolymers such as block, graft, random, and alternating copolymers, terpolymers, and higher order "x"-mers, and further includes their derivatives, combinations, and blends. Further, unless specifically limited otherwise, the term "polymer" is intended to include all possible isomeric structures of the molecules, including but not limited to isotactic, syndiotactic, and random symmetries, and combinations thereof. Further, unless specifically limited otherwise, the term "polymer" is intended to include all possible geometric structures of the molecules. 【0050】 As used herein, the term "soil" or "stain" refers to non-polar oily substances, which may or may not contain certain substances such as mineral viscosities, sand, natural minerals, carbon black, graphite, kaolin, environmental dust, etc. 【0051】 As used herein, the term "substantially free of" refers to a composition that either completely lacks that component or has a small amount of the component that does not affect the performance of the composition. The component may be present as an impurity or contaminant and is less than 0.5% by weight. In another embodiment, the amount of the component is less than 0.1% by weight, and in yet another embodiment, the amount of the component is less than 0.01% by weight. 【0052】 The terms "weight percent", "wt-%", "percent by weight", "% by weight", and their variations, as used herein, refer to the concentration of a substance obtained by dividing the weight of the substance by the total weight of the composition and multiplying by 100. It is understood that when used herein, terms such as "percent", "%", etc. are intended to be synonymous with "weight percent", "wt-%", etc. 【0053】 The methods and compositions of the present invention can include, consist essentially of, or consist of the components and ingredients of the present invention, as well as other ingredients described herein. As used herein, "consisting essentially of" means that the methods and compositions can include additional steps, components, or ingredients, provided that the additional steps, components, or ingredients do not substantially change the basic and novel characteristics of the claimed methods and compositions. 【0054】 Systems and methods for monitoring and adjusting detergent concentration Plastic and fascia cleaning systems are an important step in cleaning and removing contaminants such as release compounds, oils, dust, and dirt from fascia parts prior to the painting process. If the parts are not thoroughly cleaned, there can be paint adhesion problems, resulting in defects in the painted parts, costly rework, or the possibility of having to discard the parts. Therefore, it is essential to thoroughly clean plastic and other fascia components prior to painting. 【0055】 Standardizing processes across locations and even within a particular cleaning plant is extremely difficult. This is because water varies from location to location (and thus, there are fluctuations in mineral content and pH), and the cleaning process itself creates variations in the cleaning water based on changes in detergent concentration and fluctuations in contaminants in the water. For this reason, cleaning systems employ a repetitive manual titration program over the course of a day or at most a week. Titration has proven to be highly variable and inaccurate for many reasons. First, the titration system itself is highly dependent on local water sources such as local tap water and potentially reverse osmosis water quality. The titration method also depends on the uniform detection of the color change of chemical indicators by acid / base titration. The detection of the end point used to derive the concentration through calibration tables is highly dependent on both the operator and the location. This method is performed more accurately by a single skilled operator in a laboratory environment, but in reality, i.e., in field use, this is unrealistic and a major challenge. The ability to accurately detect, monitor, and control concentrations (without the need for titration) at different cleaning machine stages provides an important mechanism for maintaining the performance of the program at all cleaning machine stages in plastic part and fascia cleaning systems and methods. 【0056】 In an embodiment, the cleaning water can be sprayed while the parts are moving through a tunnel (or other site) that sprays the formulation. This process can be manual, partially or fully automated. In an exemplary embodiment, the process can be performed on a stationary or moving surface such as a conveyor belt that carries the parts through a sprayer. In another embodiment, the use solution of the composition can be introduced into a tank or other holding means and the parts can be submerged therein. 【0057】 The contact between the surface and the detergent wash water can be part of a multi-component process or a multi-phase system. In an embodiment, the detergent wash water is contacted with a surface that requires washing and rinsing prior to the application of a coating or paint to the surface. Exemplary steps in a process or system employing a hard surface rinse aid composition may include an initial pre-washing or hot wash step, a wash step with additional soap and / or detergent, one or more rinse steps, and a drying step. The contact between the surface and the use solution of the composition can be from about 60 seconds to several hours, from several minutes to several hours, or from about 10 minutes to about 60 minutes. 【0058】 In a preferred embodiment, the detergent wash water washes and dries the surface within about 30 seconds to several minutes, or within about 30 to about 90 seconds after the aqueous solution has been removed (i.e., the surface has been removed from the tank in which it was immersed in the composition). Preferably, the detergent wash water provides a dynamic contact angle and employs a high use concentration to provide efficient sheeting without leaving debris on the treated surface. As disclosed herein, the appropriate detergent concentration provides the optimal conditions for the detergent to induce sheeting and ensures that there is no debris remaining on the treated surface and no filming on the surface, despite the high concentration surfactant system employed. 【0059】 Although not limited to the following concentrations, preferably, the detergent wash water has a concentration of at least about 0.25% to 1% detergent and / or rinse aid in water, at least about 2% detergent and / or rinse aid in water, or at least about 3% detergent and / or rinse aid in water. Preferably, the detergent is at a concentration of less than about 10 wt%, 9 wt%, 8 wt%, 7 wt%, 6 wt% or 5 wt%. 【0060】 Referring now to the figures, FIG. 1 shows a plastic and facia cleaning system 100. The system 100 includes a pretreatment washer 102 used to clean metal and plastic substrates 98 before liquid or powder coating, and before and after machining or forming components. The washer 102 is constructed from rugged materials to enhance durability. For example, the tank 104 on the pretreatment washer 102 is double welded both inside and outside, preventing leakage. The tank 104 may further include an overflow gutter and / or drain 106 provided at all stages, made of stainless steel or mild steel, a valve for this drain 106, a filter screen 108 with a bottom sludge dam, a grip strut 110, a gas-fired immersion burner 112, a removable access cover (e.g., a tank cleaning marine door), and an inclined bottom for easy cleaning. The pretreatment washer 102 also includes an overhead conveyor 116 protected by a conveyor shroud 118. The conveyor shroud 118 is particularly beneficial when used in the spray and drain stages. The modular design of the pretreatment washer 102 allows for easier and quicker installation. 【0061】 The pretreatment washer 102 may also feature clip-on nozzles 120. Each nozzle 120 can be adjusted to direct the nozzle 120 towards the desired parts or products within the washer 102. 【0062】 The housing 122 can include stainless steel or mild steel. The housing 122 may also include an inclined drain deck, a partition access door 124 within the drain stage 102N, inlet and outlet exhaust passages, a silhouette between all spray sections 102N, and a bolted structure. 【0063】 The piping system can include quick, overhead disconnects, risers with quick disconnects, drains, overflows and reverse flow piping, a rapid fill bypass on all stages, a vertical pump 126, a thermometer on the heating stage, and a pressure gauge on all stages. 【0064】 The cleaning system 100 can be further enhanced through the use of a particle filtration system 128, an oil separation system, and / or a recirculated air blowing system 130. 【0065】 The number of stages 102N and the design of the pretreatment washer 102 depend on the complexity of the parts and the finish specifications. A typical multi-stage washer includes a chemical cleaning stage 102A followed by a water and rinse stage. A complex multi-stage washer may also include additional stages 102B - 102D, which can include, but are not limited to, a phosphate stage, additional rinse stages, and a reverse osmosis or surfactant final rinse stage. 【0066】 For example, FIG. 2A is a schematic diagram showing an example of a typical four-stage cleaning system 200 for cleaning plastics. The bath / spray washer system 200 is an energy-intensive and water-intensive process that utilizes four or five stages to move hot clean water (tap water 204 or RO water 210) as a medium. More specifically, the clean water 204 / 210 is moved between at least three separate areas 202A, 202B, 202C after passing through one or more stages in the process. The plastic parts in FIG. 2A move from the stage 1 area 202A to the stage 2 area 202B and the stage 3 area 202C. 【0067】 The areas 202A, 202B, and 202C may have a decreasing fluid volume as the stage progresses. In one exemplary embodiment, the stage 1 area 202A has a fluid volume of approximately 3480 gallons to facilitate the mixing of tap water 204 and soap 206, the stage 2 has a fluid volume of approximately 2085 gallons and receives tap water 204, and the stage 3 has a fluid volume of approximately 1775 gallons and receives RO water 210. 【0068】 Stage 1 is a chemical cleaning stage. As shown, the chemical cleaning stage receives water directly from the tap water supply 204, which is fluidly positioned upstream of the chemical cleaning stage. The soap supply 206 is also fluidly positioned upstream of the Stage 1 area 202A. As shown, the tap water supply 204 and the soap supply 206 are fluidly parallel to each other. To most easily mix the soap 206 and the water 204, nozzles, pumps, mixing devices, and the like can be employed at Stage 1. After the mixture of soap 206 and water 204 is applied to the plastic, the used mixture is allowed to exit the Stage 1 area 202A via the drain 208. To facilitate the repair of any conduit downstream of the tap water supply 204, a shut-off valve 216 can be included near the fluid input of the Stage 1 area 202A. 【0069】 This is optionally advanced by Stages 2 and 3, which are performed in areas 202B and 202C. Stages 2 and 3 are water and rinse stages. Similar to Stage 1, Stage 2 can receive a fluid input directly from the tap water supply 204, which is positioned upstream of the Stage 2 area 202B. The use of a pump 218 to facilitate the movement of water throughout the Stage 2 area 202B is particularly beneficial. Optionally, the pump 218 can also be configured to move water from the Stage 2 area through the bypass conduit 212 to the Stage 1 area 202A for use and / or reuse in the Stage 1 area 202A. The Stage 2 area 202B can further include fluid inputs from other stages (e.g., Stages 3 and 4) positioned upstream thereof. 【0070】 Stage 3 is a water and rinse stage, similar to stage 2, but instead receives purified water from RO water supply unit 210. The purified water can be received directly from RO water supply unit 210 or indirectly from RO water supply unit 210 after passing through an RO storage unit 222 having a fluid capacity of approximately 1150 gallons. Optionally, a pump can assist in moving the purified water from RO storage unit 222 to stage 3 area 202C. After the water passes through stage 3, the water may pass through an overflow tank 224 having a fluid capacity of approximately 55 gallons before being removed to stage 2 by pump 214. 【0071】 Further, to mimic a water source that has passed through an advanced water filtration system, purified water can also be supplied indirectly after passing through stage 4 - the "reverse osmosis" stage. 【0072】 FIG. 2B beneficially modifies the cleaning system of FIG. 2A in that the system 200 comprises and / or consists essentially of a sensor 302, a controller 306, a metering pump 310, and a detergent source 312. The controller 306 communicates with the sensor 302 via a sensor signal 304 and also communicates with the metering pump 310 via a control signal 308. Preferably, the communication is an electrical communication including, but not limited to, wired electrical communication and / or wireless electrical communication (including, but not limited to, wi-fi communication, Bluetooth® communication, wireless communication). 【0073】 Sensor Sensor 302 is preferably an ultraviolet (UV) meter. A suitable UV meter can be selected based on the wavelength corresponding to the excitation of the surfactant contained in the detergent employed in the cleaning process. Since there are various surfactant species, it is not limited to this spectrum, but the range of 100 nm to 280 nm is considered to cover the excitation of many surfactant species often contained in automotive detergents. In a preferred embodiment, the sensor is a UV meter that measures the transmittance in the range of 100 nm to 280 nm, more preferably 150 nm to 280 nm, even more preferably 200 nm to 280 nm, and most preferably 240 nm to 280 nm. For the purposes of the present disclosure, a 254 UV meter has been consistently employed, as it corresponds to the excitation of the surfactant used in the test detergent and was for evaluating and validating the system and method without the need to change the detergent species or equipment utilized at different locations and other test conditions. The systems and methods disclosed herein need not be limited to a 254 nm UV meter. 【0074】 In embodiments, additional sensors can be employed, including but not limited to a pH meter and / or a device for measuring conductivity. 【0075】 Sensor 302 can be provided at a location where the cleaning water is recovered following the cleaning application. At this location, Sensor 302 can be used to test a parameter that can correspond to the concentration of the detergent in the cleaning water. Thus, additional water 204 / 210 and / or detergent 312 can be added to the cleaning water to achieve the set detergent concentration. 【0076】 Sensor 302 notifies a UL-listed PLC-based control panel that is operably communicating with the electronic solution level control across all stages. The manual solution level control can be included together with this electronic solution level control across all stages, taking into account potential electrical failures. 【0077】 Controller The controller 306 includes a human-machine interface (HMI) and components for establishing communication. Examples of such a controller 306 can be a processing unit alone, a programmable logic controller (PLC), an industrial computer with enhanced durability and adapted to control manufacturing processes, a robotic device, or simply other sub-components of a computing device. The controller 306 can also include other components and can be partially or fully implemented on a semiconductor chip (e.g., a field-programmable gate array (FPGA) chip) developed through a register transfer level (RTL) design process. 【0078】 Metering pump The metering pump 310 moves an accurate volume of liquid within a specific time to provide an accurate volumetric flow rate. The delivery of fluid at an accurately adjustable flow rate is sometimes referred to as metering. The metering pump 310 is application-specific or does not require the exact type of pump used, although some types of pumps are much more suitable than most other types of pumps. The metering pump 310 can pump water, chemicals, solutions, and other liquids. The metering pump 310 is preferably rated to be able to pump at a high discharge pressure. The metering pump 310 is designed to meter at a flow rate that is substantially constant within a wide range of discharge (outlet) pressures (when averaged over time). 【0079】 Usage method The present system and method can be applied to a detergent 312 and / or a rinsing aid for cleaning automotive parts. The automotive parts can be made from a variety of materials including plastics that contain, for example, plastic and metal parts, and the metal can include aluminum that requires aluminum compatibility. Since aluminum is a soft metal, the composition requires aluminum compatibility. As referred to herein, aluminum compatibility ensures that any degree of etching that occurs on the surface does not cause corrosion and / or a significant weight loss (as a result of etching of aluminum). Certain uses can benefit from acidic compositions that can cause etching on the surface that enables adhesion of coatings such as paint, but surface corrosion is undesirable. 【0080】 The detergents 312 to which these methods and systems can be applied are varied and can be used in a variety of applications where a clean, spot-free, film-free, dry surface is required. 【0081】 The temperature of the wash water can similarly vary. The water temperature is preferably a low temperature, hot water temperature, or room temperature. As referred to herein, a low temperature includes temperatures of about 145°F (63°C) or less. In an embodiment, the temperature of the rinse water is at most about 145°F (63°C), preferably in the range of 125°F (51°C) to 145°F (63°C). As referred to herein, "low temperature" refers to a rinse water temperature of less than about 145°F (63°C). 【0082】 All publications and patent applications herein are indicative of the ordinary skill level in the technical field to which the present invention pertains. All publications and patent applications are incorporated herein by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. 【0083】 Exemplary embodiments 【0084】 The present invention is defined in the claims. However, non-limiting embodiments are non-exhaustively listed in numerical form below. Any one or more of the features of these embodiments may be combined with any one or more of the features of any other example, embodiment, or aspect described herein. Accordingly, the following numbered embodiments also form part of the present disclosure: 【0085】 A passenger vehicle plastic part and fascia cleaning system, A conveyor belt configured to convey passenger vehicle plastic parts and / or fascias, a sprayer configured to spray water containing water and / or a detergent, and a drain having an inlet to a recovered wash water container, a cleaning stage comprising A metering pump, the metering pump being configured to discharge a detergent into a mass of water and / or the recovered wash water, the metering pump, A sensor, the sensor including a UV meter, the sensor being configured to perform a UV transmittance measurement of the recovered wash water, the sensor, A controller, comprising, the controller being in electrical communication with the sensor and the metering pump, the controller storing a calibration plot of the UV transmittance versus the concentration of surfactant species in the detergent, the calibration plot including a set point, a passenger vehicle plastic part and fascia cleaning system. 【0086】 The system of claim 1, wherein the UV meter measures the transmittance or absorbance at wavelengths from 240 nm to 270 nm. 【0087】 The system of claim 1 or 2, wherein the electrical communication is wireless communication. 【0088】 The system of any one of claims 1 to 3, further comprising a pH meter or a device for measuring conductivity. 【0089】 The system of any one of claims 1 to 4, wherein the system further includes a rinsing stage, the rinsing stage comprising a sprayer configured to spray water and a second drain. 【0090】 The system of any one of claims 1 to 5, wherein the container includes a drum, a tank, and / or a tube. 【0091】 The system of any one of claims 1 to 6, further comprising a shroud for protecting the conveyor. 【0092】 The system of any one of claims 1 to 7, further comprising a recirculating air blowing system. 【0093】 The system of any one of claims 1 to 8, further comprising a particle filter. 【0094】 A kit for modifying a plastic vehicle part and a fascia cleaning system, comprising: A sensor, the sensor including a UV meter, the sensor, A metering pump, A controller comprising a transmitter and a receiver for electrically communicating with the sensor and the metering pump, the controller storing a calibration plot of UV transmittance or absorbance against the concentration of surfactant species in the detergent, the calibration plot including a set point, the kit. 【0095】 The kit of claim 10, wherein the UV meter measures the transmittance at a wavelength of 240 nm to 270 nm. 【0096】 The kit of claim 10 or 11, wherein the transmitter and the receiver communicate wirelessly. 【0097】 The kit of any one of claims 10 to 12, wherein the kit further comprises a water pump, the water pump having an output readable by the controller. 【0098】 A method for cleaning a plastic vehicle part and / or a fascia, comprising: Placing the plastic vehicle part and / or the fascia on a conveyor; Operating the conveyor through one or more cleaning stages of a cleaning system. Spraying cleaning water on plastic passenger vehicle parts and / or fascia in one or more cleaning stages of a cleaning system, wherein the cleaning water contains a detergent, and the detergent contains a surfactant; Recovering the cleaning water from one or more cleaning stages after spraying; Detecting the UV transmittance or absorbance of the surfactant in the recovered cleaning water via a sensor; Comparing the UV transmittance of the recovered cleaning water with a set point on a calibration plot; Adding water or detergent to the recovered cleaning water, wherein the amount of water and / or detergent is determined by the difference between the measured UV transmittance or absorbance and the set point on the calibration plot; Recycling the recovered cleaning water with water or detergent added thereto back into the cleaning system. A method comprising the above steps. 【0099】 The method according to claim 14, wherein there is one cleaning stage. 【0100】 The method according to claim 15, wherein the cleaning water is recovered via the drain of one cleaning stage. 【0101】 The method according to claim 14, wherein there are at least two cleaning stages. 【0102】 The method according to claim 17, wherein the cleaning water is recovered via the drains of each of the two cleaning stages and mixed in a recovered cleaning water container. 【0103】 The method according to claim 17, wherein the cleaning water is recovered via a single drain located downhill from at least two cleaning stages. 【0104】 The method according to claim 14, wherein the comparing is performed by a controller communicating with the sensor. 【0105】 The method according to claim 20, wherein the controller communicates wirelessly with the sensor. 【0106】 The method of claim 20, wherein the controller communicates with a metering pump. 【0107】 The method of claim 22, wherein the metering pump injects detergent into the recovered wash water. 【0108】 The method of claim 20, wherein the controller communicates with a water pump. 【0109】 The method of claim 24, wherein the water pump injects water into the recovered wash water. 【0110】 The method according to any one of claims 14 to 25, wherein the drain is provided with a filter. 【Examples】 【0111】 Embodiments of the present invention are further defined in the following non-limiting examples. It should be understood that these examples illustrate specific embodiments of the invention but are given by way of illustration only. From the above discussion and these examples, those skilled in the art can identify the essential features of the invention and make various changes and modifications to the embodiments of the invention without departing from the spirit and scope of the invention, and adapt them to various uses and conditions. Therefore, in addition to what is shown and described in this specification, various modifications of the embodiments will be apparent to those skilled in the art from the foregoing description. Such modifications are also intended to be included within the scope of the appended claims. 【0112】 The methods and systems disclosed herein were evaluated and tested using two separate water sources to mimic different applications that would be encountered in actual practice. In addition, one of the water sources was subjected to reverse osmosis treatment to mimic a water source passing through an advanced water filtration system. To support these examples, a RealTech UV 254 UVT meter as well as a Hach DR-6000 were used. 【0113】 Example 1 Water samples were obtained from a tap water source. Using the direct water from the tap water source, detergent cleaning water containing detergents at various concentrations was prepared. In addition, the tap water was subjected to reverse osmosis filtration to prepare the detergent cleaning water with RO water, and the difference between the ability to monitor tap water (having hardness ions) and the filtered water was compared. Conductivity measurements were performed while increasing the detergent concentration using a Micro S device. The conductivity measurement values were plotted against the concentration of the detergent on a weight percent basis, and the results are provided in Figure 3A. Thereafter, the UV transmittance was measured and plotted against the concentration of the detergent on a weight percent basis, and the results are provided in Figure 3B. The transmittance data was collected with both a Hach DR-6000 and a RealTech UV 254 UVT. 【0114】 A calibration plot (Figure 3C) was prepared to identify the standard target concentration of the detergent when cleaning plastic automotive parts and facias. This plot was tested to evaluate the ability to monitor the bounce-back, the changes in detergent concentration that can occur from the increase in residual detergent on the automotive parts and soil in the cleaning water, and these changes based on the UV transmittance. The test plot is provided in Figure 3D. The data supporting the plot is provided in tabular form in Figures 4A and 4B. As can be seen from Figures 3D, 4A, and 4B, the changes in the detergent concentration in the cleaning water can be monitored via the UV transmittance data. This can be monitored without the need for titration and can be used for automatic monitoring. Furthermore, the data demonstrated that adjustments for correcting the concentration of the detergent can be applied based on a calibration plot that identified the set points for adjusting the concentration back. In addition, the data demonstrated the ability to apply the system and method to tap water and highly filtered (RO) water. 【0115】 Example 2 Water samples were obtained from a tap water source different from that in Example 1. Conductivity measurements were performed while increasing the detergent concentration using a Micro S device. The conductivity measurement values were plotted against the concentration of the detergent on a weight percent basis, and the results are provided in Figure 5A. Thereafter, the UV transmittance was measured and plotted against the concentration of the detergent on a weight percent basis, and the results are provided in Figure 5B. In this case, the transmittance data was collected using only the RealTech UV 254 UVT. 【0116】 The ability to monitor and adjust the detergent concentration was evaluated along with the ability to monitor and adjust the concentration based on the UV transmittance readings. This test was plotted and provided in Figure 5C. The data supporting the plot is provided in tabular form in Figures 6A and 6B. As can be seen from Figures 5C, 6A, and 6B, changes in the detergent concentration in the wash water can be monitored via the UV transmittance data. This data based on different water sources demonstrates that it can be monitored without the need for titration and can be used for automatic monitoring. Furthermore, the data demonstrated that adjustments for correcting the detergent concentration can be applied based on a calibration plot that identified set points for adjusting the concentration back. 【0117】 Example 3 For comparison, the data collected in Examples 2 and 3 was compared in a log plot (Figure 7A) against the UV transmittance data based on the detergent concentration in tap water from Example 1, reverse osmosis water from Example 1, and tap water from Example 2. Since not all samples were subjected to the Hach instrument, the data compared was only the RealTech data. The data for the chart is provided in tabular form in Figure 7B. 【0118】 Again, the data based on different water sources with different filtration levels demonstrates that monitoring and adjustment can be performed without the need for titration. Furthermore, the data demonstrated that adjustments for correcting the detergent concentration can be applied based on a calibration plot that identified set points for adjusting the concentration back. 【0119】 Example 4 A water sample was obtained from the tap water source of Example 1 and subjected to reverse osmosis filtration. Using the reverse osmosis permeate, detergent cleaning water containing various concentrations of detergent was prepared. Conductivity measurements were performed using a Micro S device while increasing the detergent concentration. The conductivity measurement values were plotted against the concentration of the detergent on a weight percent basis, and the results are provided in FIG. 8A. Thereafter, UV absorbance was measured and plotted against the concentration of the detergent on a weight percent basis, and the results are provided in FIG. 8B. Transmission data was collected using only RealTech UV 254 UVA. 【0120】 The ability to monitor and adjust the concentration of the detergent was evaluated together with the ability to monitor and adjust the concentration based on the UV transmittance readings. This test is plotted and provided in FIGS. 8C and 8D. In FIG. 8C, the transmittance is measured using RealTech UV 254 UVT, and in FIG. 8D, the transmittance is measured using a Hach DR-6000. As can be seen from FIGS. 8C and 8D, changes in the detergent concentration in the cleaning water can be monitored via the UV transmittance data. This data based on different water sources demonstrates that it can be monitored without the need for titration and can be used for automatic monitoring. 【0121】 Example 5 Water samples were obtained from tap water sources different from those of Examples 1 and 2. Using the direct water from the tap water source, detergent cleaning water containing various concentrations of detergent was prepared. Conductivity measurements were performed using a Micro S device while increasing the detergent concentration. The conductivity measurement values were plotted against the concentration of the detergent on a weight percent basis, and the results are shown in FIG. 9A. Thereafter, UV absorbance was measured and plotted against the concentration of the detergent on a weight percent basis, and the results are provided in FIG. 9B. Transmission data was collected using only RealTech UV 254 UVT. 【0122】 The ability to monitor and adjust the detergent concentration was evaluated along with the ability to monitor and adjust the concentration based on the UV transmittance reading. This test is plotted and provided in Figures 9C and 9D. In Figure 9C, the transmittance was measured using RealTech UV 254 UVT, and in Figure 9D, the transmittance was measured using Hach DR-6000. Figure 10 shows the monitoring of the transmittance % and absorbance % at different washing stages. It also includes a comparison of the conductivity data. Detergent wash water was introduced into washing machine stage 2 (in particular, the conductivity measurement corresponding to that stage was inaccurate for the water source). 【0123】 As can be seen from Figures 9C, 9D, and 10, changes in the detergent concentration in the wash water can be monitored via the UV transmittance and absorbance data. This data based on different water sources demonstrates that it can be monitored without the need for titration and can be used for automatic monitoring. Further, by monitoring the transmittance and / or absorbance at different washing machine stages, it is demonstrated when the detergent has been completely rinsed from the parts within the washing machine. For example, in Figure 10, it can be seen that there is no detergent remaining at washing machine stage 5 and substantially no detergent remaining at washing machine stage 4. 【0124】 Although the invention has been described in this manner, it will be apparent that these can vary in many ways. Such changes should not be regarded as a departure from the spirit and scope of the invention, and it is intended that all such modifications be included within the scope of the following claims. The above specification provides an explanation of the manufacture and use of the disclosed compositions and methods. Since many embodiments can be made without departing from the spirit and scope of the invention, the invention is within the scope of the claims.

Claims

[Claim 1] A plastic passenger car parts and fascia cleaning system, wherein the system is A washing stage comprising a conveyor belt configured to transport plastic passenger car parts and / or fascia, a sprayer configured to spray water containing water and / or detergent, and a drain having an inlet to a container for recovered washing water, A metering pump, wherein the metering pump is configured to release detergent into a mass of water and / or recovered wash water, A water pump configured to discharge water into the water mass and / or the recovered wash water, A sensor comprising a UV meter, wherein the sensor is configured to measure the UV transmittance or absorbance of the recovered washing water, A plastic passenger car parts and fascia cleaning system, wherein the water pump is configured to discharge the water into the water mass and / or the recovered cleaning water based on the measurement of UV transmittance or absorbance, and / or the metering pump is configured to discharge the detergent into the water mass and / or the recovered cleaning water based on the measurement of UV transmittance or absorbance. [Claim 2] The system according to claim 1, wherein the UV meter measures transmittance or absorbance at wavelengths of 240 nm to 270 nm. [Claim 3] The system according to claim 1 or 2, further comprising a pH meter or a device for measuring conductivity. [Claim 4] The system according to claim 1 or 2, further comprising a rinsing stage, the rinsing stage comprising a sprayer configured to spray water, and a second drain. [Claim 5] The system according to claim 1 or 2, wherein the container includes a drum, a tank, and / or a tube. [Claim 6] The system according to claim 1 or 2, further comprising a shroud for protecting the conveyor, a recirculating air blowing system, and / or a particle filter. [Claim 7] Further comprising a controller, The controller communicates with the sensor, the metering pump, and the water pump. The controller is configured to store a calibration plot of UV transmittance or absorbance against the concentration of surfactant species in the detergent, and the calibration plot includes a set point. The system according to claim 1 or 2, wherein the controller is configured to compare the measurement of UV transmittance or absorbance with the set point, and optionally the controller is configured to perform the comparison automatically. [Claim 8] The system according to claim 7, wherein the controller is configured to automatically discharge water via the water pump and / or detergent via the metering pump into the water mass and / or the recovered wash water based on the measurement of UV transmittance or absorbance. [Claim 9] The system according to claim 7 or 8, wherein the communication between the controller and the sensor and / or the metering pump is electrical communication, and optionally the electrical communication is wireless communication. [Claim 10] A kit for modifying plastic passenger car parts and fascia cleaning systems, the kit comprising: A sensor, including a UV meter configured to measure the UV transmittance or absorbance of recovered washing water, A metering pump, wherein the metering pump is configured to release detergent into the recovered washing water based on the measurement of UV transmittance or absorbance, A water pump, wherein the water pump is configured to release water into the recovered wash water based on the measurement of UV transmittance or absorbance, A kit that includes the following: [Claim 11] The kit according to claim 10, wherein the UV meter measures transmittance at wavelengths of 240 nm to 270 nm. [Claim 12] Further comprising a controller, The controller communicates with the sensor, the metering pump, and the water pump. The controller is configured to store a calibration plot of UV transmittance or absorbance against the concentration of surfactant species in the detergent, and the calibration plot includes a set point. The controller is configured to compare the measured UV transmittance or absorbance with the set point, and optionally, the controller is configured to perform the comparison automatically. The kit according to claim 10 or 11, wherein the controller is configured to automatically discharge water via the water pump and / or detergent via the metering pump into the recovered wash water based on the measurement of UV transmittance or absorbance. [Claim 13] The kit according to claim 12, wherein the water pump has an output readable by the controller. [Claim 14] A method for cleaning plastic passenger car parts and / or fascia, wherein the method is: Placing plastic passenger car parts and / or fascias on a conveyor, Operating the conveyor through one or more washing stages of the washing system, In one or more cleaning stages of the cleaning system, cleaning water containing a detergent containing a surfactant is sprayed onto the plastic passenger car parts and / or fascia. After spraying, the cleaning water is recovered from one or more of the cleaning stages. The UV transmittance or absorbance of the surfactant in the recovered washing water is detected via a sensor. Based on the UV transmittance or absorbance, water and / or the detergent is added to the recovered washing water. A method comprising recirculating the recovered washing water, into which water and / or the detergent has been added, back into the washing system. [Claim 15] The method according to claim 14, wherein there is one cleaning stage. [Claim 16] The method according to claim 15, wherein the washing water is recovered through the drain of the one washing stage. [Claim 17] The method according to claim 14, wherein there are at least two washing stages. [Claim 18] The method according to claim 17, wherein the washing water is recovered through the drains of each of the two washing stages and mixed in a recovered washing water container. [Claim 19] The method according to claim 17, wherein the washing water is collected through a single drain located at a downward slope from the at least two washing stages. [Claim 20] The method of claim 14, further comprising comparing the UV transmittance or absorbance with a setpoint on a calibration plot via a controller communicating with the sensor, wherein the comparison is optionally performed automatically by the controller. [Claim 21] The method according to claim 20, wherein the controller communicates wirelessly with the sensor. [Claim 22] The method according to claim 20, wherein the controller communicates with the metering pump. [Claim 23] The method according to claim 22, wherein the dispensing of the detergent is performed automatically via the controller, and the metering pump dispenses the detergent into the recovered wash water. [Claim 24] The method according to claim 20, wherein the controller communicates with the water pump. [Claim 25] The method according to claim 24, wherein the water is added automatically via the controller, and the water pump adds the water to the recovered wash water. [Claim 26] The method according to claim 16, 18, or 19, wherein the drain comprises a filter.

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