A device for converting tap water into hard water

Abstract

The utility model relates to a device for converting tap water into hard water, comprising a reverse osmosis filtering unit, a medicine adding unit, a mixed water tank, a storage water tank and a control unit, the inlet of the reverse osmosis filtering unit is connected with tap water, the outlet of the reverse osmosis filtering unit is provided with a flowmeter, and the outlet of the reverse osmosis filtering unit is connected with the mixed water tank, the medicine adding unit comprises a plurality of medicine tanks, the outlet of each medicine tank is provided with a peristaltic pump, and each medicine tank is connected with the mixed water tank, and the mixed water tank is connected with the storage water tank, the flowmeter is connected with the control unit, the flow information of the outlet of the reverse osmosis filtering unit is transmitted to the control unit, the control unit is connected with the peristaltic pump, and the rotational speed of the peristaltic pump is controlled. The utility model can automatically add the hard water adjusting agent according to the flow of soft water, can realize adding at any time, automatic adding and accurate adding, can save labor and improve efficiency.

Description

Technical Field

[0001] This utility model relates to the field of washing machine performance testing technology, specifically to a device for converting tap water into hard water. Background Technology

[0002] As an essential household appliance, washing machines are subject to stringent market access requirements in most countries and regions worldwide. Before entering the market, they undergo a series of performance tests according to the standards and regulations of various countries. Among these, the International Electrotechnical Commission (IEC) standard IEC 60456:2024 is a crucial standard for washing machine performance testing. This standard requires that the hardness range of the hard water used in the test be 2.5 mmol / L ± 0.2 mmol / L. Ensuring the accuracy and stability of water hardness is essential for consistent test results. Currently, this is mainly achieved by manually adding reagents, which requires monitoring the water level in the tank and manually weighing, dissolving, adding, and stirring the reagents to the hard water tank, resulting in high labor costs. Summary of the Invention

[0003] The purpose of this invention is to overcome the defects of the prior art and provide a device for converting tap water into hard water.

[0004] To achieve the purpose of this utility model, this application provides the following technical solution.

[0005] In a first aspect, this application provides an apparatus for converting tap water into hard water. The apparatus includes a reverse osmosis filtration unit, a chemical addition unit, a mixing tank, a storage tank, and a control unit. The inlet of the reverse osmosis filtration unit is connected to tap water, and the outlet of the reverse osmosis filtration unit is equipped with a flow meter and connected to the mixing tank. The chemical addition unit includes multiple chemical tanks, each of which has a peristaltic pump at its outlet and is connected to the mixing tank. The mixing tank is connected to the storage tank. The flow meter is connected to the control unit and transmits the flow rate information of the reverse osmosis filtration unit outlet to the control unit. The control unit is connected to the peristaltic pump and controls the rotational speed of the peristaltic pump.

[0006] In this application, tap water passes through a reverse osmosis filtration unit, which removes impurities and metal ions, thereby reducing the hardness of the tap water to below 0.5 mmol / L, which can be roughly considered pure water. Simultaneously, a flow meter is installed in the outlet pipeline to transmit real-time soft water flow data to the control unit. The control unit then controls the speed of the peristaltic pump, thereby adjusting the flow rate of the hardness-regulating reagent and controlling the amount of soft water and hardness regulator added, ensuring that the final hard water concentration meets the testing standards.

[0007] In one embodiment of the first aspect, the reverse osmosis filtration unit includes a filter, a water pump, and a reverse osmosis membrane assembly connected in sequence, wherein the filter is connected to tap water, and the outlet of the reverse osmosis membrane assembly is connected to a mixing tank.

[0008] In one embodiment of the first aspect, the number of filters is ≥2.

[0009] In one embodiment of the first aspect, the flow meter is a rotor flow meter. Because the ion concentration in soft water is very low, other flow meters would yield inaccurate results; therefore, a rotor flow meter is chosen.

[0010] In one embodiment of the first aspect, the drug addition unit includes three drug tanks, each containing a NaHCO3 solution, a MgSO4·7H2O solution, and a CaCl2·2H2O solution, and each drug tank is equipped with a stirring paddle.

[0011] In one embodiment of the first aspect, the medicine tank is equipped with a liquid level sensor. When the liquid level in the medicine tank is lower than a set value, the liquid level sensor sends a signal to the control unit, which then sends a signal to the alarm to remind the operator to add hardness adjuster. Each time the medicine is added, the amount of solid material and deionized water is fixed, ensuring that the material concentration in each medicine tank remains constant.

[0012] In one embodiment of the first aspect, an electromagnetic flow meter is provided at the outlet of the medicine tank. The electromagnetic flow meter is installed at the outlet of the medicine tank to display the outflow rate of each medicine tank, thereby ensuring the flow ratio of soft water to hard water conditioner.

[0013] In one embodiment of the first aspect, the inlet of the mixing tank is located at the top of the tank, the outlet is located at the bottom of the tank, and a stirring paddle is provided inside the tank. This arrangement is to allow sufficient mixing time for the soft water and hard water conditioner in the mixing tank, thereby resulting in a more uniform concentration.

[0014] In one embodiment of the first aspect, the storage tank is equipped with a stirring paddle. In this application, the stirring paddles in both the storage tank and the medicine tank are used to ensure a more uniform solution concentration within each tank, preventing stratification.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows: The device described in this application can automatically add hard water conditioner according to the flow rate of soft water. It can add the conditioner at any time, automatically, and accurately, which can save labor and improve efficiency. Attached Figure Description

[0016] Figure 1This is a schematic diagram of the structure of this application.

[0017] In the attached diagram, 1 is a filter, 2 is a water pump, 3 is a reverse osmosis membrane module, 4 is a NaHCO3 reagent tank, 5 is a MgSO4·7H2O reagent tank, 6 is a CaCl2·2H2O reagent tank, 7 is a first agitator, 8 is a level gauge, 9 is a peristaltic pump, 10 is a rotor flow meter, 11 is an electromagnetic flow meter, 12 is a mixing tank, 13 is a second agitator, 14 is a second motor, 15 is a storage tank, 16 is a third agitator, 17 is a third motor, and 18 is a first motor. Detailed Implementation

[0018] Unless otherwise defined, the technical or scientific terms used in this specification and claims shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. All values ​​listed herein, ranging from the minimum to the maximum, refer to all values ​​obtained by incrementing the minimum and maximum values ​​by one unit when the difference between the minimum and maximum values ​​is more than two units.

[0019] The following describes specific embodiments of this utility model. It should be noted that, in order to provide a concise description, this specification cannot provide a detailed description of all features of the actual embodiments. Without departing from the spirit and scope of this utility model, those skilled in the art can modify and substitute the embodiments of this utility model, and the resulting embodiments are also within the protection scope of this utility model.

[0020] A device for automatically converting municipal tap water into hard water includes: Water tank: Used to store tap water for supplying reverse osmosis membrane filtration devices; Reverse osmosis membrane filtration device: Encloses a pre-filter, water pump, and reverse osmosis membrane, which can filter out ions in tap water and reduce the hardness of tap water to below 0.05 mmol / L; at the same time, a flow meter is installed in the water outlet pipeline, which can transmit real-time flow data to the control board. The control board can control the peristaltic pump to add hardness adjustment reagent to the large water tank according to the flow rate.

[0021] Hardness-regulating reagent tank: The hardness-regulating reagent is pre-dissolved in the tank and then injected into the hard water tank via a peristaltic pump. The tank has a stirring blade on top for continuous agitation, ensuring a homogeneous and stable solution. There are three types of hardness-regulating reagents: NaHCO3, MgSO4·7H2O, and CaCl2·2H2O; therefore, three tanks are provided.

[0022] Peristaltic pump: A peristaltic pump is installed on the top of the medicine tank, which can adjust the amount of reagent added in real time according to the flow rate.

[0023] Hard water tank: The hard water tank is a water tank that holds hard water. It is also a place where soft water and hardness adjustment reagents are mixed evenly. The hard water tank is equipped with a stirring motor and stirring blades to help the hardness adjustment agent and water dissolve fully and ensure that the water hardness in the tank is uniform. Example

[0024] The embodiments of this utility model will be described in detail below. These embodiments are implemented based on the technical solution of this utility model and provide detailed implementation methods and specific operation processes. However, the protection scope of this utility model is not limited to the following embodiments. Example

[0025] A device for converting tap water into hard water, the structure of which is as follows: Figure 1 As shown, the device includes a reverse osmosis filtration unit, a drug addition unit, a mixing tank 12, a storage tank 15, and a control unit, as detailed below.

[0026] The reverse osmosis filtration unit includes two filters 1, a water pump 2, and a reverse osmosis membrane module 3, arranged sequentially. Filter 1 is connected to tap water, or it can be connected to a tap water tank, and then the tap water tank is connected to tap water. This embodiment uses the former. The outlet of the reverse osmosis membrane module 3 is connected to the bottom of the mixing tank 12, and a rotor flow meter 10 is installed on the connecting pipeline to detect the flow rate of soft water.

[0027] The drug addition unit includes three tanks: a NaHCO3 tank 4, a MgSO4 tank 5, and a CaCl2 tank 6. Each tank is equipped with a first stirring paddle 7 and a level gauge 8. The first stirring paddle 7 is driven by a first motor 18. Each tank is also equipped with a peristaltic pump 9 at its top, which is connected to the top of a mixing tank 12. An electromagnetic flow meter 11 is installed on the connecting pipeline for each tank.

[0028] A second motor 14 is provided on the top of the mixing tank 12 to drive the second agitator 13 inside the mixing tank 12. A water outlet is provided at the bottom of the mixing tank 12 and connected to the storage tank 15. A third motor 17 is provided on the top of the storage tank 15 to drive the third agitator 16 inside the storage tank 15. The bottom of the storage tank 15 is connected to the washing machine detection device.

[0029] The control unit is not shown in the figure. It can be a PLC controller or a microcontroller. It is connected to the rotor flow meter 10 and the electromagnetic flow meter 11 to monitor and record the real-time flow of soft water and three hard water conditioners, and to control the speed of the peristaltic pump 9 based on the data from the rotor flow meter 10.

[0030] The working principle of this device is as follows (substitute actual values).

[0031] In this embodiment, based on the molecular weights of commonly used laboratory analytical grade NaHCO3, MgSO4·7H2O, and CaCl2·2H2O reagents, the amount of reagents required to prepare a total hardness of 2.5 mmol / L (total hardness = [Ca²⁺] + [Mg²⁺]) per 1L of pure water is calculated quantitatively, as follows:

[0032] 1. Objective: Prepare 1 liter of hard water with a total hardness of [Ca²⁺] + [Mg²⁺] = 2.5 mmol / L.

[0033] 2. Proportion setting: Set the Ca²⁺ concentration to approximately 1.85 mmol / L and the Mg²⁺ concentration to approximately 0.65 mmol / L. This totals 2.5 mmol / L.

[0034] 3. Calculation source: Hardness contribution comes from: CaCl2·2H2O provides Ca²⁺ MgSO4·7H2O provides Mg²⁺ NaHCO3 provides bicarbonate (HCO3⁻) to simulate the alkalinity of natural hard water (according to IEC 60734 and GB / T23119, when the hardness is 2.5 ± 0.20 mmol / L, the alkalinity is 3.35 ± 0.20 mmol / L). Please note: the addition of NaHCO3 does not affect the hardness value; hardness is determined solely by divalent metal ions.

[0035] Step 1: Calculate the required drug quantity We need to calculate the mass of each reagent required to prepare 1 liter (1000 mL) of solution.

[0036] 1. Calculate the amount of CaCl2·2H2O to be used (providing 1.85 mmol Ca²⁺). The molar mass of CaCl₂·2H₂O = 40.08 (Ca) + 70.9 (Cl₂) + 36.03 (2H₂O) = 147.01 g / mol Required moles = 1.85 mmol = 0.00185 mol Required mass = Number of moles × Molar mass = 0.00185 mol × 147.01 g / mol = 0.2720 g 2. Calculate the amount of MgSO4·7H2O to be used (providing 0.65 mmol Mg²⁺). Molar mass of MgSO4·7H2O = 24.31 (Mg) + 96.06 (SO4) + 126.11 (7H2O) = 246.48 g / mol Required moles = 0.65 mmol = 0.00065 mol Required mass = 0.00065 mol × 246.48 g / mol = 0.1602 g 3. Calculate the amount of NaHCO3 to be used (providing approximately 3.35 mmol HCO3⁻). The molar mass of NaHCO3 = 23 + 1 + 12 + 48 = 84.01 g / mol Required moles = 3.35 mmol = 0.00335 mol Required mass = 0.00335 mol × 84.01 g / mol = 0.2814 g Formula summary table (for 1L solution)

[0037] Therefore, based on the above linear relationship, the laboratory calculates the real-time dosage of the reagents used, the dosage of the reagents added to the NaHCO3 tank 4, MgSO4·7H2O tank 5 and CaCl2·2H2O tank 6, and the real-time output of the pure water purification device, and the control unit adjusts the amount of reagents added according to the above ratio.

[0038] Suppose that at a certain moment, the rotor flow meter 10 detects a flow rate of 6 L / min at the outlet of the reverse osmosis membrane module 3. The dosing tank contains 1407.0g NaHCO3 dissolved in 50000 mL (tank 4), 801.0g MgSO4·7H2O dissolved in 50000 mL (tank 5), and 1360.0g CaCl2·2H2O dissolved in 50000 mL (tank 6).

[0039] Based on the above data, the drug concentration and dosage in each medicine box are as follows: <![CDATA[CaCl2·2H2O]]> 1360.0 50000 0.02720 6*0.2720=1.632 / 0.0272=60ml / min <![CDATA[MgSO4·7H2O]]> 801.0 50000 0.01602 6*0.1602=0.9612 / 0.01602=60 ml / min <![CDATA[NaHCO3]]> 1407.0 50000 0.02814 6*0.2814=1.6884 / 0.02814=60 ml / min The control unit calculates the dosing rate corresponding to 6 L / min under the condition of 6 ml / min based on the information imported by the user and the real-time water output synchronization information. Then, it controls the speed of the peristaltic pump 9 and adjusts the output flow rate of the hard water conditioner until the flow rate detected by the electromagnetic flow meter 11 is 60 mL / min. In this way, the hard water stored in the storage tank 15 finally meets the standard of 2.5 mmol / L ± 0.2 mmol / L.

[0040] The above description of the embodiments is intended to enable those skilled in the art to understand and apply this application. It will be apparent to those skilled in the art that various modifications can be easily made to these embodiments, and the general principles described herein can be applied to other embodiments without creative effort. Therefore, this application is not limited to the embodiments described herein, and any improvements and modifications made by those skilled in the art based on the disclosure of this application without departing from the scope and spirit of this application are within the scope of this application.

Claims

1. A device for converting tap water into hard water, characterized in that, The device includes a reverse osmosis filtration unit, a chemical addition unit, a mixing tank, a storage tank, and a control unit. The inlet of the reverse osmosis filtration unit is connected to tap water, and the outlet of the reverse osmosis filtration unit is equipped with a flow meter and connected to the mixing tank. The chemical addition unit includes multiple chemical tanks, each of which has a peristaltic pump at its outlet and is connected to the mixing tank. The mixing tank is connected to the storage tank. The flow meter is connected to the control unit and transmits the flow information from the outlet of the reverse osmosis filtration unit to the control unit. The control unit is connected to the peristaltic pump and controls the rotational speed of the peristaltic pump.

2. The apparatus for converting tap water into hard water as described in claim 1, characterized in that, The reverse osmosis filtration unit includes a filter, a water pump, and a reverse osmosis membrane assembly connected in sequence. The filter is connected to tap water, and the outlet of the reverse osmosis membrane assembly is connected to a mixing tank.

3. The apparatus for converting tap water into hard water as described in claim 2, characterized in that, The number of filters is ≥2.

4. The apparatus for converting tap water into hard water as described in claim 1, characterized in that, The flow meter is a rotor flow meter.

5. The apparatus for converting tap water into hard water as described in claim 1, characterized in that, The drug addition unit includes three drug tanks, which contain NaHCO3 solution, MgSO4·7H2O solution and CaCl2·2H2O solution respectively, and each drug tank is equipped with a stirring paddle.

6. The apparatus for converting tap water into hard water as described in claim 5, characterized in that, The medicine box is equipped with a liquid level sensor.

7. The apparatus for converting tap water into hard water as described in claim 5, characterized in that, An electromagnetic flow meter is installed at the outlet of the medicine box.

8. The apparatus for converting tap water into hard water as described in claim 1, characterized in that, The inlet of the mixing tank is located at the top of the tank, the outlet is located at the bottom of the tank, and the tank is equipped with a stirring paddle.

9. The apparatus for converting tap water into hard water as described in claim 1, characterized in that, The storage tank is equipped with a stirring paddle.

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