The cleaning, disinfection and sanitation projects of equipment, pipelines and environment in beer craft brewing plants are crucial and are the decisive factors related to product quality. No matter how good the quality of malt, hops, yeast and water is, it is impossible to produce pure-tasting beer in a set of contaminated equipment and pipelines. Especially with the improvement of automation in craft beer production, there are a large number of automatic valves, detection instruments and fixed and non-detachable hard-connected pipes in the equipment, which puts forward higher requirements for the configuration of the CIP system. CIP cleaning and disinfection is a systematic project. It is not possible to configure a good CIP station to complete the cleaning and disinfection of equipment and pipelines. It also requires close cooperation with the equipment and pipelines to be cleaned to achieve the best cleaning and disinfection effect. At the same time, the consumption of water, energy (including electricity and heat), and cleaning and disinfection additives are minimal. This is a perfect CIP system for craft beer factories. This article mainly explains the basic configuration requirements of the CIP system in the saccharification process based on modern CIP cleaning technologies and methods.
1 Saccharification equipment cleaning technology and requirements
The saccharification system is a hot zone in the beer craft brewing factory, and the materials basically operate between 50 and 100 degrees. Therefore, the saccharification CIP system mainly considers cleaning. There are also small parts such as cold wort pipelines that need to consider cleaning and sterilization at the same time. The basic requirement of the CIP system is to deliver the cleaning liquid with optimal temperature and pressure to the containers and pipelines and complete the cleaning process according to the prescribed steps and time. The material and water containers and material pipelines of the saccharification process are required to be cleaned in separate cycles.
1.1 Cleaning solution: Mainly rely on 2-3% alkali solution (NaOH) for hot cleaning and 2.5% phosphoric acid cleaning solution for cold cleaning.
1.2 Cleaning steps and time: Pre-rinsing: 10-20 minutes, 2-3 times of intermittent flushing (recycled water can be used)
Cleaning: long cycle 40-60min, short cycle 20-30min
Rinse: 10-20 minutes using hot water first and then normal temperature water (later rinse water is recycled as pre-rinse water for the next cleaning)
Test: No alkali or acid residue
1.3 Cleaning temperature: For saccharification equipment and pipelines, the CIP alkali temperature is 82 degrees (pay attention to the return water temperature requirement to reach 82 degrees during cycle cleaning), and pickling is suitable for room temperature.
2.Configuration of saccharification CIP station
The saccharification CIP station consists of tanks, pumps, heat exchangers, filters, distributors, pipeline valves and instruments;
2.1 Tank: Usually configured with 2 tanks including recycled water tank and alkali tank or 4 tanks including recycled water, alkali tank 1, alkali tank 2 and acid tank. The volume design of the tank is related to the volume of the CIP liquid supply and return pipelines. A properly designed CIP tank can reduce equipment costs and consumption of steam and cleaning agents; CIP tanks are required to have a self-cleaning function.
2.2 Pump: The CIP supply pump adopts a centrifugal pump. The flow design of the pump is related to the flow rate required by the washing ball or can washer for container cleaning and the required flow rate of the washing liquid in the pipeline. The lift design of the pump is related to the flow rate required by the washing ball or can washer for container cleaning. The pressure required by the tank and the length and height of the CIP supply pipeline are related to the number of fittings and valves on the pipeline. The CIP reflux pump adopts a self-priming pump, which can self-prime and transport the CIP liquid in the container and CIP reflux pipe, so that no liquid remains in the container.
2.3 Heat exchanger: For heating CIP liquid (including heating of hot water and alkali liquid), tubular or plate heat exchangers can be used. The tube type has the advantage of being less likely to be blocked but has low thermal efficiency. Nowadays, plate heat exchangers are mostly used.
2.4 Filter: Use a filter with backwash and install it on the CIP return line. Some parts of the saccharification system, such as the gelatinization pot and the boiling pot, will have large particles of cleaning material, which can easily block the filter. When the flow rate drops, response should be made in time. Flush the filter.
2.5 The distributor can be in the form of a manual take-over plate or an automatic valve array. The distributor distributes the CIP liquid to the containers and pipes that need to be cleaned. It should be noted here that the location of the CIP distributor must be relatively close to the containers and pipes that need to be cleaned. , generally placed in the central area of the workshop, which can be further away from the CIP station.
2.6 Instrumentation: Each pot tank is equipped with a manhole door switch and a CIP cleaning indicator light; the CIP alkali tank and the recycled water tank are equipped with temperature and liquid level sensors; the CIP acid tank is equipped with a liquid level sensor; the CIP supply pump outlet is equipped with a pressure sensor and an electromagnetic sensor Flow meter; CIP return pipeline is equipped with conductivity, PH meter, flow switch and temperature sensor; the inlet and outlet of the filter are equipped with pressure display.
3.Cleaning and frequency of saccharification equipment
The cleaning effect of saccharification equipment is closely related to the selection of scrubbers. Generally, there are ball washers and tank washers to choose from. The tank washer uses an impact cleaning method: it uses the combination of two asynchronous rotations in the axial and radial directions to form a 360-degree spherical high-pressure cleaning mode, which can quickly clean every point on the inner surface of the entire container to be cleaned, with high efficiency and cleaning The time is short and the inlet pressure of the tank washer is controlled between 4 and 8 bar. The cleaning ball is a flow cleaning method: the liquid sprayed onto the upper part of the container and the cylinder flows down along the tank wall like a falling film, and the dirt particles dissolved in the detergent are washed away by the falling film. The cleaning ball pressure is required to be controlled between 1.5 and 2.5bar, its biggest advantage is that it is maintenance-free. Currently, small-diameter craft beer saccharification vessels are generally equipped with washing balls to perform CIP cleaning of each tank. However, many equipment manufacturers ignore the type, quantity and installation of washing balls. The choice of location results in incomplete cleaning of parts, especially those with mechanical devices inside. If possible, it is recommended to configure a can washer, which will provide different cleaning effects and reduce energy and cleaning agent consumption.
Recommended cleaning frequency: in the case of continuous production
Clean daily (or every 8 pots): mash pot, boil pot, wort cooler
Clean every 1 week (or every 56 pots): mash pot, filter tank
Monthly (or every 240 pots) cleaning: temporary storage tank, whirlpool sedimentation tank
For discontinuous production, cleaning must be done after shutdown and before startup.
4.Cleaning and frequency of saccharification pipelines
The cleaning of pipelines requires CIP liquid to flush and clean with turbulent flow in the pipeline at a certain flow rate. Therefore, there are two important factors for pipeline cleaning: first, the CIP liquid maintains a certain flow speed in the pipeline, and second, the CIP liquid needs to establish turbulence when flowing in the pipeline. The flow rate requirements of CIP liquid in the pipeline are: 1m/s for pipes greater than DN150; 2m/s for pipes DN150-DN100; 3m/s for pipes less than DN100. Only in this way can the CIP liquid maintain a turbulent flow state and achieve a good cleaning effect.
Recommended cleaning frequency: in the case of continuous production
Daily (or every 8 pots) cleaning and sterilization: cold wort pipe
Monthly (or every 240 pots) cleaning: mash and hot wort lines
For discontinuous production, cleaning must be carried out after shutdown and before startup.
Recommended cleaning frequency: in the case of continuous production
Clean daily (or every 8 pots): mash pot, boil pot, wort cooler
Clean every 1 week (or every 56 pots): mash pot, filter tank
Monthly (or every 240 pots) cleaning: temporary storage tank, whirlpool sedimentation tank
For discontinuous production, cleaning must be done after shutdown and before startup.
5 Cleaning of special parts of saccharification
5.1 Cleaning of the heater in the boiling pot: The heater in the boiling pot adopts a tubular type. The wort goes through the tube side and the steam goes through the shell side. If there is no wort preheating system, the wort will be about 74 degrees when it first starts heating, and the steam will go out. The temperature is about 130 degrees. The temperature difference is large and the wort flows slowly in the tube. It is easy to produce scorch and stick to the inner surface of the heater, which affects the heating efficiency and requires regular cleaning. The frequency of cleaning is related to the temperature difference, the design length of the internal heating tube and the surface finish. There are two methods for cleaning the internal heater. One is to use the ball washing method: install multiple washing balls at the upper and lower parts of the inner heater according to the diameter of the heater, and flush the heater from the upper and lower parts respectively. Washing balls also need to be installed on the guide tube and distribution umbrella for cleaning; the second method is to use alkali boiling method, add alkali solution that has not passed the internal heater to the boiling pot, and then turn on the steam heating to make the alkali solution inside the heater This method requires a large amount of alkali liquid and a large-volume alkali tank. This method has a short cleaning time and good cleaning effect.
5.2 Cleaning under the screen plate of the filter tank: The scrubber installed in the filter tank cannot directly clean the bottom plate of the filter tank because there is a filter screen plate in the middle. The distance between the filter screen plate and the bottom plate of the filter tank is 20-30mm, and the space is limited. , only special cleaning nozzles can be installed. The nozzles generally spray washing liquid at a certain angle (150-180 degrees) to wash the bottom of the filter tank. The nozzles are designed with a one-way valve to prevent the wort from flowing out from the nozzles. The number of nozzles designed is consistent with the bottom of the tank. The number of wort collection ports is the same and correspond one to one. When installing the nozzles, pay attention to the direction in which each nozzle sprays the washing liquid, and form a swirling flow in one direction (counterclockwise or clockwise).
6 Cleaning of micro-saccharification equipment
For small saccharification equipment with 2 or 3 vessels under 2 tons, it is recommended to use a CIP station with the fermentation system. It is also possible not to set up a CIP station, and each pot tank is equipped with a self-circulating CIP pipeline, and the boiling alkali self-circulating method is used for cleaning. The method is as follows: Prepare alkali solution with a concentration of 2-3% in a heatable pot (saccharification or boiling pot). For safety reasons, it is recommended to use normal temperature water to prepare alkali and then heat it to 82 degrees, and turn on the material pump for circulation cleaning. After the cleaning time is up, it is pumped into the next container to continue cleaning. After cleaning, the alkali liquid is directly discharged into the sewage treatment system without recycling. After alkali cleaning is completed, circulate clean water until no alkali remains. If there is no continuous production, clean it with hot alkali after stopping production and clean it with hot water before feeding.
A good set of craft beer saccharification equipment can not only complete the saccharification process steps, but CIP cleaning is also a key process. Some equipment consumes a lot of electricity, heat energy, water and cleaning agents during the CIP process and is still not satisfactory. The cleaning effect is closely related to the hygienic design of the saccharification equipment, the internal surface finish of the equipment processing, whether there are cleaning dead corners in the pipeline installation, and the selection of valves, instruments, heat exchangers, and pumps. At the same time, the beer factory CIP cleaning process formulation and detergent selection and other factors are also very important. Therefore, to achieve a perfect CIP effect requires the joint efforts of equipment design, manufacturing and installation companies, beer craft factories, and detergent manufacturers.
