Basic cleaning operation process of CIP system

First water rinse

The first water rinsing is also called "pre-washing". It is mainly to wash away the material residues and viscous liquids in the cleaned equipment, containers, and pipes as much as possible, so that as little as possible enters the washing (liquid) tank. The water used for pre-washing is generally discharged; in order to save water, the pre-washing water is often the recovered part of the post-washing water. Moreover, the pre-wash tanks are generally relatively large, and the pre-wash process takes about 10-15 minutes. The larger the equipment to be cleaned, the longer the flushing time. If the cleaning equipment used is simpler, such as using a washing ball, the washing time will be longer.

Acid cleaning or alkaline cleaning

Alkaline cleaning or acid cleaning is to use alkaline detergent or acidic detergent to clean the equipment more thoroughly on the basis of pre-washing. Remove sticky residual organic matter, including viscous granular residues such as starch granules, hop resin, protein, paste, caramel, etc. that are sintered on the heated surface, as well as precipitated and attached solids. This washing process takes a long time, about 20-40min. This is the main cleaning procedure of CIP cleaning, and the real washing effect is mainly reflected in this process.

There are two aspects to this process:

One is the so-called alkaline cleaning or pickling, not just using a certain concentration of alkali or acid, but a synthetic detergent containing various cleaning aids such as surfactants, water softeners, descaling agents, and chelating agents. The choice of detergent should be based on the ability and degree of dirt removal of alkaline or acidic detergents and the needs of the environment to be cleaned.

Secondly, the method of using alkali cleaning or pickling should be selected according to the object to be cleaned, and the method of alkali and acid cross cleaning can be used to meet the cleaning requirements. For example, when cleaning a large tank, you can wash it with an alkali cleaning agent first, rinse off the residual alkali after the end, and then use an acidic detergent for circular cleaning, often to obtain better cleaning results. When carrying out alkaline cleaning, the cleaning agent should be heated to 80-85°C (or a more suitable temperature), and when carrying out pickling, it should be carried out at room temperature. Some dirt will be washed off during alkali or pickling, and some solid dirt will be brought out. Therefore, it is advisable to install a filter to filter out the particles before the alkali or acid is recycled into the corresponding storage tank, which can increase the repetition of detergent and reduce the amount of sediment in the tank.

Second wash

The second water washing is also called "post-washing". After alkali washing or pickling, the alkali or acid remaining in the container and pipeline is washed away until the flushed water is neutral.

After washing, pay attention to several issues:

First, in order to prevent the detergent from being diluted by water, all the detergent must be recovered before proceeding.

The 2nd, in order to save water, most of back washing water can be reclaimed into " front washing water " tank, used as the first flushing water (aforesaid).

The third is to consider saving flushing water. It is necessary to neutralize with dilute acid or dilute alkali before post-washing. For hot alkali washing, most of the post-washing water is hot water, which not only has a good washing effect, but also has a good disinfection effect. Therefore, "post-washing" can be regarded as the final process of CIP cleaning. For cold pickling, the post-wash water is mostly room temperature water, and its aseptic condition is very important. If the post-wash water contains bacteria, it means that secondary pollution has occurred, so it must be rinsed with disinfectant water to meet the requirements; it can also be used In the second half of the post-washing process, disinfectants are added online to perform post-washing and disinfection at the same time.

Disinfectant rinse

Disinfectant flushing is to ensure that the aseptic conditions of equipment and pipelines are further satisfied in the case of cold pickling, and it is often recirculated with a suitable concentration of disinfectant solution after post-washing. The selected disinfectant is preferably after flushing, and its residual liquid will not have any impact on the product, nor will it cause corrosion to the equipment, such as peracetic acid, chlorine dioxide, hydrogen peroxide, etc., so that it is unnecessary to use Sterile water was used for repeated rinsing. In order to ensure product quality and food safety, modern beer brewing strongly opposes the use of formaldehyde-based fungicides to sterilize large tanks, sake tanks and beer pipelines, because formaldehyde residues will cause beer drinking safety problems.

Rinse with sterile water

Precautions

First, the requirements for the preparation of sterile water are relatively high, and equipment including storage containers and pipelines must meet sterile conditions.

Second, if the sterile state of sterile water cannot meet the requirements, the flushing effect will be counterproductive.

The third is to prolong the flushing process of CIP and increase the amount of flushing water.