An on-line purification system and method for caustic solution used in cleaning of recycled bottles in a brewery

Abstract

The application discloses an alkali liquor online purification treatment system and method for beer factory recycling bottle cleaning, and adopts a combined process of 'pretreatment + ceramic membrane cross-flow filtration'. First, large-particle suspended matters are removed through a pretreatment unit, then partial filtrate is deeply filtered through a ceramic membrane to remove colloids and fine particles, and finally, the concentrated liquid is treated through oil separation and sedimentation. The application can realize continuous online purification of alkali liquor, significantly prolong the service life of alkali liquor, improve bottle cleaning quality, reduce operation cost, and has good economic and environmental benefits.

Description

Technical Field

[0001] This invention relates to the field of industrial fluid treatment technology, specifically to an online purification, filtration, and recycling system and method for sodium hydroxide (NaOH) alkaline solution used for cleaning and recycling bottles in beer production, and is particularly applicable to the treatment of alkaline solution in bottle washing machines in brewery packaging workshops. Background Technology

[0002] In the beer production process, cleaning recycled bottles is a crucial step in ensuring product quality. Currently, breweries commonly use high-temperature sodium hydroxide solution to soak and spray-clean recycled bottles. However, as cleaning batches continue, various contaminants accumulate in the alkaline solution, mainly including: suspended matter such as label fibers, dirt, dust, and plastic fragments detached from the bottle; viscous colloidal substances formed from the hydrolysis of food residues, proteins, and polysaccharides; oily saponifications formed by the reaction of bottle residues with the alkaline solution; and pigments formed by the dissolution of residual beverage pigments and label inks from the bottle.

[0003] To remove the aforementioned pollutants, existing factories commonly use traditional filtration equipment such as stainless steel filter cartridges or automatic backwashing filters. However, due to limitations in equipment structure and filtration mechanisms, these traditional solutions have many shortcomings in practical applications: First, the filtration accuracy is low. The pore size of existing filtration equipment is usually between 2 and 10 mm, which can only intercept foreign objects with a particle size greater than 5 mm. It cannot effectively remove tiny suspended solids and colloidal substances, making it difficult for the alkaline solution to meet the requirements of high-quality cleaning.

[0004] Secondly, the filter screen is prone to clogging. Long fibrous materials such as paper fibers easily entangle and clog the filter screen, resulting in insufficient spray pressure, reduced cleaning efficiency, and the need for frequent machine shutdowns for manual cleaning.

[0005] Third, poor cleaning quality. Because colloidal substances cannot be effectively retained, they will form residues or water stains on the bottle wall, resulting in mold, odors, oil stains, or discoloration after washing, which seriously affects product quality and increases the risk of customer complaints.

[0006] Fourth, there is a serious waste of resources. Because the alkali solution cannot be effectively purified, it is usually discharged from the entire tank after 2 to 3 days of use. This not only results in a large consumption of alkali solution and high wastewater treatment costs, but also causes a large amount of heat energy to be lost with the waste liquid, resulting in low energy utilization.

[0007] Fifth, high operating costs. Traditional filtration equipment requires a large amount of manual labor for cleaning and maintenance, and the operating environment poses safety hazards such as alkaline burns. Furthermore, frequent replacement of filter media and downtime for maintenance further increase operating costs. Summary of the Invention

[0008] The present invention aims to solve the problems of insufficient filtration accuracy, serious waste of alkali solution, unstable bottle washing quality and high operating costs in the above-mentioned prior art.

[0009] To solve the above-mentioned technical problems, the present invention provides the following technical solution: an online alkali purification system for cleaning recycled bottles in breweries, comprising an alkali tank for a bottle washing machine, a pretreatment unit, a ceramic membrane filtration unit, and an oil separation and sedimentation unit; the outlet of the alkali tank for the bottle washing machine is connected to the inlet of the pretreatment unit; the outlet of the pretreatment unit is divided into a first branch and a second branch, the first branch flowing back to the alkali tank for the bottle washing machine, and the second branch connecting to the inlet of the ceramic membrane filtration unit; the clear liquid outlet of the ceramic membrane filtration unit flowing back to the alkali tank for the bottle washing machine, and the concentrated liquid outlet of the ceramic membrane filtration unit connecting to the inlet of the oil separation and sedimentation unit.

[0010] As an improvement, the pretreatment unit is used to remove suspended matter with a particle size greater than 0.1 mm.

[0011] As an improvement, the ceramic membrane filtration unit uses an inorganic ceramic membrane for cross-flow filtration to remove colloids and fine particles with a particle size greater than 0.0001 mm.

[0012] As an improvement, the inorganic ceramic membrane has a pore size of 50-100 nm and is made of alumina or zirconium oxide.

[0013] As an improvement, the traffic splitting ratio between the first branch and the second branch is 80%:20%.

[0014] As an improvement, the oil separation and sedimentation unit allows the concentrate to stand and separate into layers. The upper layer of oil is discharged through the overflow port, the lower layer of solids is discharged through the bottom, and the middle layer of clear liquid is returned to the inlet of the pretreatment unit.

[0015] As an improvement, the system is equipped with a PLC automatic control system.

[0016] As an improvement, the operating pressure of the ceramic membrane filtration unit is 0.1-0.5 MPa, and the operating temperature range is 5-95℃.

[0017] It also includes an online purification method for alkali solution based on the above system, comprising the following steps: S1. Extract the alkaline solution from the alkaline tank of the bottle washing machine and transport it to the pretreatment unit for pretreatment. After removing large particulate suspended matter, the filtrate is divided into two paths. One path flows directly back to the alkaline tank of the bottle washing machine, and the other path enters the ceramic membrane filtration unit. S2. The filtrate entering the ceramic membrane filtration unit is finely filtered in cross-flow filtration mode to obtain clear liquid and concentrated liquid. S3. The clarified liquid is returned to the alkaline tank of the bottle washing machine, and the concentrated liquid is transported to the oil separation and sedimentation unit. S4. The concentrated liquid is allowed to stand and separate into layers in the oil separation and sedimentation unit. The upper layer of oil is discharged, the lower layer of solids is discharged, and the middle layer of clear liquid is returned to the pretreatment unit for recycling.

[0018] The advantages of this invention compared to the prior art are: (1) High-precision filtration performance: It breaks through the limitations of traditional filtration precision (2-10mm) and achieves nanoscale (100nm) filtration precision by using ceramic membrane. It can effectively remove colloidal substances and fine suspended matter that cause the decline in bottle washing quality. The filtration precision is more than 1,000 times higher than that of traditional equipment.

[0019] (2) Significantly extend the life of alkali solution: By deeply removing organic pollutants that cause alkali solution aging, the life of alkali solution can be extended by 1-2 times, the consumption of alkali solution can be reduced by about 40%-60%, and the frequency of alkali solution discharge can be reduced by more than 90%.

[0020] (3) Significantly improve the quality of bottle washing: completely eliminate the adhesion of colloids on the bottle wall, solve the problems of sticky bottle wall, water stains, mold and odor, increase the bottle washing qualification rate to more than 99.5%, and significantly reduce the customer complaint rate.

[0021] (4) Significant energy saving and emission reduction effects: Reduces alkaline discharge by more than 90%, significantly reduces wastewater treatment load, reduces heat loss, improves energy utilization efficiency, reduces the amount of chemical agents used, and reduces environmental pollution.

[0022] (5) High degree of intelligence and automation: The system can operate fully automatically without manual intervention. The ceramic membrane can be regenerated through automatic backwashing without manual disassembly and cleaning of the filter screen, eliminating the safety hazards of manual cleaning and greatly reducing the labor intensity of operators. Attached Figure Description

[0023] Figure 1 This is a flowchart of an online alkali purification system for cleaning recycled bottles in a brewery, according to the present invention. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0025] like Figure 1 As shown, Example 1: Application in a 40,000 bottles / hour production line 1. Equipment configuration: Pre-processing unit: Equipped with a processing capacity of 10m³3 A vibrating screen filter with a capacity of / h and a filtration accuracy of 0.1mm, using a stainless steel screen or polymer filter element; Ceramic membrane filtration unit: Equipped with a processing capacity of 1.5m³ 3 A ceramic membrane module with a pore size of 50-100 nm, made of alumina or zirconium oxide, employing a multi-channel tubular structure, operating pressure of 0.1-0.5 MPa, operating temperature range of 5-95℃, and membrane flux of 50-200 L / m³. 2 • h, the backwashing cycle is 2-4 hours; Auxiliary facilities: Oil-water separator sedimentation tank (2m³) 3 PLC automatic control system and online monitoring instruments (including online monitoring instruments for pressure, flow, temperature, turbidity, etc.); Piping system: Food-grade stainless steel piping, equipped with flow regulating valves.

[0026] 2. Operation process: Step 1 (Coarse Filtration): The alkaline solution flows from the bottom of the alkaline tank and is filtered through the pretreatment unit. Approximately 80% (8m³) 3 The liquid ( / h) returns directly to the alkali tank via the first branch, ensuring the high-flow-rate spraying requirements of the bottle washing machine; the remaining 20% ​​(2m 3 / h) enters the fine filtration unit via the second branch; Step 2 (Fine Filtration): 2m 3 A flow rate of liquid per hour enters the ceramic membrane system. Driven by a pressure of 0.3 MPa, using the cross-flow filtration principle, clean water flows out through the ceramic membrane wall, while pollutants are trapped inside the membrane tube to form a concentrate. Step 3 (Reuse): Ceramic membrane permeate water (approximately 1.5-1.8m³) 3 The solution is clear and transparent, and the COD (chemical oxygen demand) drops from 8920 mg / L to below 7200 mg / L. The clear liquid is directly returned to the alkali tank through the outlet to replenish the solution. Step 4 (Slag Removal): The concentrated liquid produced by the ceramic membrane (approximately 0.2-0.5 ml) 3 The oil sludge enters the oil-water separation sedimentation tank at a certain temperature. After settling and stratification, the upper layer of oil sludge is discharged through the overflow outlet, the lower layer of solids is discharged through the bottom, and the middle layer of clear liquid is returned to the inlet of the pretreatment unit for recycling.

[0027] 3. Operational data: Purification efficiency: The entire alkali tank can be circulated and purified once within 1 hour (removing substances with a particle size greater than 0.1mm); a full fine filtration can be completed within 12 hours (removing substances with a particle size greater than 0.0001mm). Treatment results: The alkali solution replacement cycle was extended from the original 3 days to 7-10 days, and the bottle washing quality was significantly improved; Economic benefits: The investment payback period is approximately 2.37 years, with annual cost savings of nearly 470,000 yuan.

[0028] Example 2: Application in a 20,000 bottles / hour production line For smaller production lines, the system configuration should be adjusted accordingly: Pretreatment unit: 5m 3 / h processing capacity; Ceramic membrane unit: 0.8m 3 / h processing capacity; The overall system energy consumption is reduced by 40%, and investment costs are reduced by 30%.

[0029] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. An online alkali solution purification system for cleaning recycled bottles in breweries, characterized in that: This includes the bottle washing machine's alkali tank, pretreatment unit, ceramic membrane filtration unit, and oil separation and sedimentation unit; The outlet of the alkali tank of the bottle washing machine is connected to the inlet of the pretreatment unit; The outlet of the pretreatment unit is divided into a first branch and a second branch. The first branch flows back to the alkali tank of the bottle washing machine, and the second branch is connected to the inlet of the ceramic membrane filtration unit. The clear liquid outlet of the ceramic membrane filtration unit is returned to the alkali tank of the bottle washing machine, and the concentrated liquid outlet of the ceramic membrane filtration unit is connected to the inlet of the oil separation and sedimentation unit.

2. The system according to claim 1, characterized in that: The pretreatment unit is used to remove suspended matter with a particle size greater than 0.1 mm.

3. The system according to claim 1, characterized in that: The ceramic membrane filtration unit uses an inorganic ceramic membrane for cross-flow filtration to remove colloids and fine particles with a particle size greater than 0.0001 mm.

4. The system according to claim 1, characterized in that: The inorganic ceramic membrane has a pore size of 50-100 nm and is made of alumina or zirconium oxide.

5. The system according to claim 1, characterized in that: The traffic splitting ratio between the first branch and the second branch is 80%:20%.

6. The system according to claim 1, characterized in that: The oil separation and sedimentation unit allows the concentrate to settle and separate into layers. The upper layer of oil is discharged through the overflow port, the lower layer of solids is discharged through the bottom, and the middle layer of clear liquid is returned to the inlet of the pretreatment unit.

7. The system according to claim 1, characterized in that: The system is equipped with a PLC automatic control system.

8. The system according to claim 1, characterized in that: The ceramic membrane filtration unit operates at a pressure of 0.1-0.5 MPa and a temperature range of 5-95℃.

9. A method for online purification of alkaline solution based on the system described in any one of claims 1-8, characterized in that, Includes the following steps: S1. Extract the alkaline solution from the alkaline tank of the bottle washing machine and transport it to the pretreatment unit for pretreatment. After removing large particulate suspended matter, the filtrate is divided into two paths. One path flows directly back to the alkaline tank of the bottle washing machine, and the other path enters the ceramic membrane filtration unit. S2. The filtrate entering the ceramic membrane filtration unit is finely filtered in cross-flow filtration mode to obtain clear liquid and concentrated liquid. S3. The clarified liquid is returned to the alkaline tank of the bottle washing machine, and the concentrated liquid is transported to the oil separation and sedimentation unit. S4. The concentrated liquid is allowed to stand and separate into layers in the oil separation and sedimentation unit. The upper layer of oil is discharged, the lower layer of solids is discharged, and the middle layer of clear liquid is returned to the pretreatment unit for recycling.

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