阅读说明：本技术 糖化设备清洗方法 (Cleaning method for saccharification equipment ) 是由 刘奋强 涂京霞 梁敬坤 李铭 王培武 杨华 林风联 于 2019-09-10 设计创作，主要内容包括：本发明提供一种糖化设备清洗方法,涉及啤酒生产设备清洗技术领域。本发明的清洗方法,包括以下步骤：判断结垢情况：查看糖化设备内壁的垢层,当垢层呈黄色时,且厚度为0.05～0.10mm时,判断其为轻垢；当垢层呈棕色或棕褐色时,且厚度为0.10～0.50mm时,判断其为重垢；清洗：当判断为轻垢时,采用复合CIP清洗；当判断为重垢时,采用强化除垢清洗。本发明的糖化设备清洗方法,具有有效消除垢层、避免不锈钢设备受损的优点。(The invention provides a cleaning method of saccharification equipment, and relates to the technical field of cleaning of beer production equipment. The cleaning method comprises the following steps: and (4) judging the scaling condition: checking a scale layer on the inner wall of the saccharification equipment, and judging that the scale layer is light scale when the scale layer is yellow and the thickness of the scale layer is 0.05-0.10 mm; when the scale layer is brown or tan and the thickness is 0.10-0.50 mm, judging the scale layer to be heavy scale; cleaning: when the scale is judged to be light, cleaning by adopting composite CIP; and when the heavy scale is judged, adopting reinforced descaling and cleaning. The cleaning method of the saccharification equipment has the advantages of effectively eliminating the scale layer and avoiding the damage of the stainless steel equipment.)

1. A cleaning method of saccharification equipment is characterized by comprising the following steps:

And (4) judging the scaling condition: when the scale layer on the inner wall of the saccharification equipment is yellow and the thickness is 0.05-0.10 mm, judging that the scale layer is light scale; when the scale layer on the inner wall of the saccharification equipment is brown or tan and the thickness is 0.10-0.50 mm, judging that the scale layer is heavy scale;

Cleaning: when the scale is judged to be light, cleaning by adopting composite CIP; when the heavy scale is judged, adopting reinforced descaling and cleaning;

The reinforced descaling cleaning method comprises the following steps:

S11, washing with alkali liquor: washing the saccharification equipment by water, circularly washing by using alkaline liquor, and then washing by water until the pH value of the washing liquor is 6.5-7.5;

s12, acid liquor cleaning: circularly washing with acid liquor, and then flushing until the pH value of the washing liquor is 6.5-7.5;

S13, washing with an enhanced alkali solution: circularly washing with a reinforced alkali solution, wherein the reinforced alkali solution comprises an alkaline compound and sodium hypochlorite, and the concentration of the sodium hypochlorite is 200-600 ppm;

S14, washing with composite alkali liquor: circularly washing with a composite alkali solution, wherein the composite alkali solution comprises an alkaline compound, EDTA (ethylene diamine tetraacetic acid) and a nonionic surfactant, and then washing until the pH value of the washing solution is 6.5-7.5;

the composite CIP cleaning method comprises the following steps:

S21, washing with alkali liquor: washing the saccharification equipment by water, circularly washing by using alkaline liquor, and then washing by water until the pH value of the washing liquor is 6.5-7.5;

S22, acid liquor cleaning: circularly washing with acid liquor, and then flushing until the pH value of the washing liquor is 6.5-7.5;

s23, washing with composite alkali liquor: and circularly washing with a composite alkali solution, wherein the composite alkali solution comprises an alkaline compound, EDTA (ethylene diamine tetraacetic acid) and a nonionic surfactant, and then washing until the pH value of the washing solution is 6.5-7.5.

2. The cleaning method for saccharification equipment of claim 1, wherein in the enhanced descaling cleaning, the enhanced lye cleaning step precedes the complex lye cleaning step.

3. the method of cleaning saccharification apparatus of claim 2, wherein the alkaline compound is selected from the group consisting of: one or two of NaOH and KOH.

4. The cleaning method for a saccharification apparatus of claim 3, wherein the mass concentration of the alkaline compound in the intensified alkali solution and the composite alkali solution is 2.0% -3.0%.

5. The cleaning method for saccharification equipment as claimed in any one of claims 1 to 4, wherein in the enhanced descaling and composite CIP cleaning step, the alkali solution is a sodium hydroxide solution with a mass concentration of 2.0-3.0%, and the acid solution is a nitric acid solution with a mass concentration of 0.5-1.0%.

6. the cleaning method for a saccharification apparatus of claim 5,In the steps of S11 alkali liquor cleaning and S21 alkali liquor cleaning, the flow rate of alkali liquor circulating flushing is 40-100 m³The circulation temperature is 80-85 ℃, and the circulation time is 30-60 min.

7. The cleaning method for a saccharification apparatus as claimed in claim 6, wherein in the S13 washing step with the intensified alkali solution, the flow rate of the intensified alkali solution circulation washing is 40-100 m³the circulation temperature is 80-85 ℃, and the circulation time is 60-240 min.

8. The cleaning method for saccharification equipment of claim 6 or 7, wherein in the steps of S14 complex alkali washing and S23 complex alkali washing, the concentration of EDTA is 2000-4000 ppm.

9. the cleaning method for a saccharification apparatus of claim 8, wherein in the S14 complex lye cleaning and S23 complex lye cleaning steps, the nonionic surfactant is selected from the group consisting of: the nonionic surfactant comprises one or more of octyl phenol polyoxyethylene ether, fatty alcohol polyoxyethylene ether and nonyl phenol polyoxyethylene ether, and the concentration of the nonionic surfactant is 200-500 ppm.

10. Use of a method according to any one of claims 1 to 9 for cleaning a stainless steel saccharification apparatus.

Technical Field

the invention relates to the technical field of cleaning of beer production equipment, in particular to a cleaning method of saccharification equipment.

background

The saccharification equipment is important equipment for producing beer, and most of the saccharification equipment is made of stainless steel. After the saccharification equipment is used for a period of time, CIP cleaning is needed to remove dirt on the inner wall of a pipeline and the equipment and eliminate the influence of foreign matters generated by spoilage microorganisms on the flavor of the beer, and the cleaning of the saccharification equipment is a key step for improving the flavor quality of the beer.

In the saccharifying step of beer production, proteins and saccharides are easy to denature and coke on the inner wall of saccharifying equipment and adhere to the inner wall of the equipment, the proteins and saccharides are difficult to effectively clean by using traditional alkali liquor CIP cleaning, and in the past, a large amount of protein denaturation polymers, calcium-magnesium organic compounds and saccharide cokes adhere to the inner wall of saccharifying equipment to gradually form yellow, brown or tan dirt layers, and the existence of the dirt layers has great influence on the flavor of beer. At present, no proper cleaning process for saccharification equipment exists, and the yellow, brown or tan dirt layer is cleaned on the premise of not damaging the saccharification equipment.

Disclosure of Invention

Therefore, the cleaning method for the saccharification equipment is needed to solve the problem that the existing cleaning process cannot thoroughly clean the caramelized dirt layer, is particularly suitable for cleaning the stainless steel saccharification equipment, and can effectively remove the yellow, brown or tan dirt layer on the premise of not damaging the stainless steel saccharification equipment.

A cleaning method of saccharification equipment comprises the following steps:

and (4) judging the scaling condition: when the scale layer on the inner wall of the saccharification equipment is yellow and the thickness is 0.05-0.10 mm, judging that the scale layer is light scale; when the scale layer on the inner wall of the saccharification equipment is brown or tan and the thickness is 0.10-0.50 mm, judging that the scale layer is heavy scale;

Cleaning: when the scale is judged to be light, cleaning by adopting composite CIP; when the heavy scale is judged, adopting reinforced descaling and cleaning;

The reinforced descaling cleaning method comprises the following steps:

S11, washing with alkali liquor: washing the saccharification equipment by water, circularly washing by using alkaline liquor, and then washing by water until the pH value of the washing liquor is 6.5-7.5;

S12, acid liquor cleaning: circularly washing with acid liquor, and then flushing until the pH value of the washing liquor is 6.5-7.5;

S13, washing with an enhanced alkali solution: circularly washing with a reinforced alkali solution, wherein the reinforced alkali solution comprises an alkaline compound and sodium hypochlorite, and the concentration of the sodium hypochlorite is 200-600 ppm;

S14, washing with composite alkali liquor: circularly washing with a composite alkali solution, wherein the composite alkali solution comprises an alkaline compound, EDTA (ethylene diamine tetraacetic acid) and a nonionic surfactant, and then washing until the pH value of the washing solution is 6.5-7.5;

The composite CIP cleaning method comprises the following steps:

S21, washing with alkali liquor: washing the saccharification equipment by water, circularly washing by using alkaline liquor, and then washing by water until the pH value of the washing liquor is 6.5-7.5;

S22, acid liquor cleaning: circularly washing with acid liquor, and then flushing until the pH value of the washing liquor is 6.5-7.5;

s23, washing with composite alkali liquor: and circularly washing with a composite alkali solution, wherein the composite alkali solution comprises an alkaline compound, EDTA (ethylene diamine tetraacetic acid) and a nonionic surfactant, and then washing until the pH value of the washing solution is 6.5-7.5.

at present, the cleaning of high molecular materials such as biological membranes by using sodium hypochlorite is a common method for removing proteins on the biological membranes, however, reports of applying sodium hypochlorite to the cleaning of stainless steel equipment have not been found so far, because: the hypochlorous acid is decomposed to generate chloride ions, the chloride ions can be adsorbed on a passivation film of stainless steel equipment to extrude oxygen atoms out, the chloride ions are combined with cations in the passivation film to generate soluble chloride, small etching pits are generated on exposed base metal, the aperture of each small etching pit is about 20-30 mu m, the small etching pits are also called as hole etching nuclei and are active centers generated by etching holes, and the stainless steel can generate large-area corrosion near the hole etching nuclei along with the reaction. As mentioned in "influence of Cl ions on critical pitting temperature of 304, 316 stainless steel" published in "corrosion science and anticorrosion technology" vol 27, No. 1 by wu wei, et al: pitting corrosion is one of the important failure modes of stainless steel. As a typical stainless steel pitting inducing factor, the pitting action of chloride ions on stainless steel prevents people from adopting sodium hypochlorite to clean stainless steel equipment. Sodium hypochlorite can produce irreversible injury to stainless steel, and the washing liquid that contains sodium hypochlorite is more unlikely to adopt in the industry to wash stainless steel saccharification equipment, otherwise can seriously influence the life of stainless steel equipment, increases the economic burden of enterprise on foot.

However, in the practice and research process of the inventor, it is found that, due to long-term heating of stainless steel saccharification equipment, macromolecules such as protein can form polymers to be adhered to the surface of the equipment due to thermal denaturation, saccharides can be caramelized after being heated at high temperature for a long time, the viscosity is increased rapidly, the polymers can also be adhered to the surface of the equipment firmly, the adhered matters can not be removed by a conventional cleaning method, and a scale layer is accumulated in the day and the month, and the inventor considers that the scale layer can be used ingeniously, namely, the scale layer is used as a protection layer of the stainless steel, so that the inner wall of the stainless saccharification equipment is not in direct contact with a washing solution containing sodium hypochlorite, and according to different conditions of the scale layer, an alkali solution containing the sodium hypochlorite with a specific concentration is arranged:

NaClO+H₂O＝NaOH+HClO

R-NH-R+HClO→R₂NCl+H₂O (wherein R-NH-R is a high molecular protein polymer)

HClO→H⁺+Cl^-+[O]

It can be seen that sodium chlorate is continuously consumed and gradually disappears in the cleaning process, hypochlorite ions in the cleaning solution basically disappear when the stainless steel is exposed to be directly contacted with the cleaning solution, and the concentration of the generated chloride ions is also in a lower range. The stainless steel in the passive state has certain reaction capability to chloride ions, namely, the dissolution and re-passivation (repair) of the passive film can be in a dynamic balance state; when the concentration of the chloride ions in the solution is low and not dominant, the balance cannot be broken, and the passivation film cannot be damaged. The initial concentration of the sodium hypochlorite is 200-600 ppm, so that the primary color of metal on the inner wall of the stainless steel saccharification equipment can be reduced, and the generated chloride ion concentration is in a safe range (below 40 ppm), so that the stainless steel passive film cannot be corroded.

The thickness range of the scale layer is summarized in the practical process of the inventor for many years, and the condition is not beyond the range generally.

In summary, the above cleaning method for the saccharification equipment adopts different cleaning methods for different scaling conditions, especially for the serious scaling condition (i.e. heavy scaling) of the stainless steel saccharification equipment, adopts a combined cleaning method of intensified cleaning and conventional CIP cleaning, wherein the sodium hypochlorite is matched with the alkaline solution to effectively remove protein, nucleic acid macromolecules and saccharide cokes in the scale layer, hypochlorite ions are continuously consumed in the process of intensified cleaning with the alkaline solution, and the content of chloride ions is in a safe range after cleaning, so that the stainless steel material is not corroded, and the effect of effectively cleaning the scale without damaging the equipment is achieved.

In one embodiment, in the enhanced scale removal cleaning, the enhanced alkaline cleaning step precedes the complex alkaline cleaning step.

In one embodiment, the basic compound is selected from: one or two of NaOH and KOH.

In one embodiment, the mass concentration of the alkaline compound in the strengthening alkali liquor and the compound alkali liquor is 2.0-3.0%.

In one embodiment, in the steps of enhanced descaling cleaning and composite CIP cleaning, the alkali solution is a sodium hydroxide solution with a mass concentration of 2.0-3.0%, and the acid solution is a nitric acid solution with a mass concentration of 0.5-1.0%.

In one embodiment, in the steps of S11 lye cleaning and S21 lye cleaning, the flow rate of lye circulation washing is 40-100 m³The circulation temperature is 80-85 ℃, and the circulation time is 30-60 min. The circulation of the alkali liquor is controlled to be 40-100 m according to the area of the saccharification equipment and the diameter of the pipeline³the washing force of the cleaning process on the surface of the equipment is ensured; meanwhile, the cleaning and sterilizing effects of the equipment are guaranteed at 80-85 ℃ for 30-60 min.

In one embodiment, in the step of S13 washing with the enhanced alkali solution, the flow rate of the enhanced alkali solution circulation washing is 40-100 m³The circulation temperature is 80-85 ℃, and the circulation time is 60-240 min.

in one embodiment, in the steps of S14 complex lye cleaning and S23 complex lye cleaning, the concentration of the EDTA is 2000-4000 ppm.

In one embodiment, in the steps of S14 complex lye cleaning and S23 complex lye cleaning, the nonionic surfactant is selected from the group consisting of: the nonionic surfactant comprises one or more of octyl phenol polyoxyethylene ether, fatty alcohol polyoxyethylene ether and nonyl phenol polyoxyethylene ether, and the concentration of the nonionic surfactant is 200-500 ppm.

The invention also provides an application of the cleaning method of the saccharification equipment in cleaning the stainless steel saccharification equipment.

Compared with the prior art, the invention has the following beneficial effects:

The invention provides a high-efficiency clean composite cleaning method of saccharification equipment on the basis of deeply researching the forming principle of a scale layer on the inner wall of the saccharification equipment, which adopts different cleaning methods aiming at different scaling conditions, particularly adopts a method for strengthening scale removal and cleaning aiming at the condition of serious scaling of stainless steel saccharification equipment, wherein sodium hypochlorite is matched with alkali liquor to effectively remove protein macromolecules and carbohydrate cokes in the scale layer, hypochlorite ions are continuously consumed in the process of strengthening the cleaning of the alkali liquor, the content of chloride ions is in a safe range after the cleaning is finished, the corrosion to stainless steel materials is avoided, and the effects of effectively cleaning the scale and not damaging the equipment are achieved. During continuous production, the frequency of composite CIP cleaning is once every three months, and the conventional CIP cleaning is normally used, so that the scaling of saccharifying equipment can be effectively avoided, and the consistency of beer flavor and the stability of quality are ensured.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the preferred embodiments. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.