Solvent process: all staff should be familiar with the process of tetrachlorethylene working in the facilities of dry cleaning in order to use it safely. As shown in the figure 3.2, terachlorethylene firstly flows into a drum from a container and then flows back into the container after being filtered, which makes the process of cleaning circulate.
Cleaning methods
①the operation of dry cleaning machine
First, control the drum to rotate backward and forward.
Second, control the drum to rotate backward and forward; raise the temperature of cleaning mixture without going through radiator, whose process is as the following: drum→button trap→pump→liquid-watching window→drum.
Third, control the drum to rotate backward and forward; lower the temperature of cleaning mixture through radiator.
②three methods of dry cleaning:
First, simple dry cleaning: used under the circumstance that some auxiliary is added to the solvent of dry cleaning, which is used to clean some less contaminated clothes.
Second, a second dry cleaning: add auxiliary into the dry-cleaning solvent for the first washing. After two or three minutes, recycle the solvent through button trap into a container for a simple dehydration. Then the solvent is going to be pumped from a tank of cleaning solvent into the drum for a second washing. (this is the process of rinsing rather than the cycle of washing).
Third, dry cleaning with auxiliary: auxiliary is added into solvent during this process, in which filtering and circulating function. In general, after dry cleaning with auxiliary, a second dry cleaning is demanded.
③Washing time (illustrated in figure 3.4, for reference).
Figure 3.4 washing time table
Clothing types
|
Normal
|
White
|
Woolen、overcoat
|
Silk、cashmere
|
Nap、wrinkles
|
Real leather and fur
|
Washing time/min
|
10~20
|
5~10
|
10~20
|
5~10
|
4~8
|
8~15
|
Figure 3.5 Dewatering time table
Clothing types
|
Normal
|
White
|
Woolen、overcoat
|
Silk、cashmere
|
Nap、wrinkles
|
Real leather and fur
|
Dehydration time/min
|
2.5
|
2.5
|
3
|
2
|
2.5
|
1.5
|
⑤Drying temperature (illustrated in figure 3.6, for reference).
Figure 3.6 Drying temperature
Clothing types
|
Normal
|
White
|
Woolen、overcoat
|
Silk、cashmere
|
Nap、wrinkles
|
Real leather and fur
|
Drying temperature/℃
|
48~52
|
48~50
|
48~50
|
45~48
|
46~59
|
42~45
|
About the facility configuration
①Since the facility configuration changes, please refer to the random instruction according to your own configuration. To the same part between the facility to be configured and that in training center, we will train locally. To the different part, we will offer training at your home.
②Attentions to using dry-cleaning machine
First, dry-cleaning machine should be installed in a room where is ventilated, dry, no flammable stuff and corrosive gases. If it is not well-ventilated, ventilation should be installed.
Since machine should be kept level, hard rubber and cardboard can be used as an underlay under its four legs. Besides, there should be space of 0.8 meters to 1 meter between the back of machine and wall for easy operation.
Electric circuit should be connected according to national standard. Especially the bolt of machine with earthing marks must connect with reliable protective earthing. Meanwhile, resistance is no more than 4 ohms and wire is no less than 2.5 square millimeters.
Second, working room should be well-ventilated.
Third, no flames are allowed.
Fourth, electric circuit must be installed by professional electricians, and the bolt of machine with earthing marks must connect with reliable protective earthing.
Fifth, amateurs are forbidden to alter any parameters.
Sixth, please turn off the power at off-duty time.
③Maintenance of facility
First, check the oil, screws and noises during its operation. Turn off the machine for any abnormality. Reuse will not be allowed until malfunctions are all excluded.
Second, lubricating oil in guide bearings and transmission should be added and replaced to ensure good lubricating performance.
Third, check conveyor belt frequently. If it becomes loose, keep it tight.
Fourth, To do a thorough check on the machine every year, and make a necessary repair based on concrete situation.
Finally, consumers should pay attention: please keep machine and workplace clean. Favorable environment is good for not only machine performance but also attracting consumers.
(IV) Washing
Washing is a process, in which washing are acted on by the chemical power of detergent and the mechanical power of washing machine, and the effect is up to the organic combination between the surface force in detergent and the friction force by washing machine’s operating.
1. principle and basic knowledge of washing
(1) in general, two washing tools: semi-automatic washing machine; full-automatic washing machine.
①Semi-automatic washing machine. Semi-automatic washing machine is usually made up of washing drum and dehydrating drum, which can automatically finish washing and rinsing in sequence except for dehydration. After washing and rinsing, washing should be put into dehydrating drum for timing dehydration.
②Full-automatic washing machine. Procedures which are chosen in advance with control key in necessary place are set washing, rinsing, dehydrating, watering, draining and drying automatically.
(2)washing conditions
①Water. Washing mainly depends on water, and there are “soft” water and “hard” water, which are different in the number of soluble metal ions in water, such as iron,calcium and magnesium. Water with more metal ions is “hard”, or it is “soft”. However, there are many standards in the world to differentiate them.
Our country usually use Germany Hardness Standard in which one hardness means that there are 1mg CaO in 100mg water. Hardness less than five is “soft”, or it is “hard”. Water in the north China is generally “hard”. Washing with “hard” water is not only wasting detergent but also having effects on washing.
②Water temperature. Temperature is one of the main washing conditions and it has an important effect on washing. The followings are its functions:
First, detergent (especially soap) can solute fast into foam in some temperature of water, in which detergent molecule is strongly active so that its function can be fully brought into play.
Second, fiber expands when it is heated, which is good for clearing up dirt. Fiber can expand by wetting, and to some degree, it stops expanding. If temperature can up to some degree, fiber can keep on expanding to its maximum.
Third, water molecule obtains energy when it is heated, which enhances the function of wetting and infiltration. Generally speaking, various kinds of detergents are better at removing stains under the conditions of warmer temperature of water. However, the characters of of clothing should be taken into consideration, for example, rayon, silk and wool as raw material are resistant to high temperature, so lower temperature is usually chosen. Hot water is not suitable for clothing in dark colors, either. It is better to wash dirty clothing which is not resistant to high temperature with warm water.
(3)Washing material. Method: suitable for washing silk and wool-woven clothing. 5~10 kilograms for 1 kilogram dry clothing.
①Detergent for bloodstains (powder).
Function: the product uses the formula of high-tech bio- enzyme that is expert in removing bloodstains, milkstains and other protein stains; it is also good at removing hemoglobin and plant-bases stains, and has the function of disinfectant to meet the requirements of hotels and hospitals.
Methods: soaking washing in 1%~2% solution formed from warm water (under 50℃) 30 minutes or more. When it comes to part processing, please sprinkle the product over stains to make them dissolve. Brush them after 30 minutes of wetting. Don’t mix it with chlorine-based bleaching powder, bleaching water and other disinfectants.
Attention: don’t use water over 50℃ to deal with bloodstains for overheated water will curdle hemoglobin and make it hard to decompose enzyme. As a result, it is more difficult to remove bloodstains.
②Cleaning mixture.
Cleaning mixture can keep the original hue of clothing and keep white clothing from becoming yellow and gray, which would happen when other detergents are used. By using cleaning mixture, colorful clothing can become more bright, and others can keep their origins. It also has the function of disinfection so that infectious diseases can be effectively controlled.
③Anti-bubbling agent.
Function: the product which is formed from silicon and anti-bubbling polyether can eliminate bubbles shaped during blanket washing. When few anti-bubbling agent is added into liquids with bubbles, the bubbles will disappear quickly. It also functions effectively in clear or dirty water, and is suitable for blanket-washing machine, water-absorbing machine and others which need to eliminate bubbles.
Methods: add 30~50 milliliter anti-bubbling agent into the drum of blanket-washing machine or into the drum of dirty water, and then operate as normal.
2. Methods of washing down products
There are two kinds of fabrics, TC and nylon, used to make down products. Since they are mainly blended fabrics of cotton yarn, they should be soaked in cold water before washing. Besides, washing such kinds of products needs high-quality detergent specializing in cleaning down products or cleansing powder. First wash the products in washing machine with water about 40℃ for about 20 minutes, and then put them in washboard and focus on cleaning dirty parts. After these, put them back into the washing machine for further washing of 3~5 minutes. It is better to rinse once and dehydrate once, or to rinse twice first with warm water and then once with cold water. The next step is acid treatment and air the washing after dehydration. Finally, lash them with cane so that they can be completely fluffy.
3. Laundry washing series
Laundry-specialized washing detergents are in the form of powder and liquid, which are divided into the following several types: alkaline additives, emulsifying agent, synthetic detergents, bleaching agent, softener, acid acceptor and other special additives.
(1) Alkaline additives. Alkaline additives are strong alkaline substances added in pre-washing or main-washing process.
①Principle of removing oil by alkali. Removing the oil on fabrics by alkali is not always useful, since alkali can only react with vegetable oils but not mineral oil.
②Principle of removing protein stains by alkali. The main components of alkaline additive is strong alkaline substances, so it is very important to operate safely, especially with liquid alkaline products. After washing with strong alkali, it is definitely necessary to rinse the washing thoroughly. In general, it should add acid acceptor in the last rinse, or the remains of alkali will yellow the color of fabrics
(2) The main detergents. Synthetic detergents are in fact the main detergents. The main detergents are used in the main process of washing. They can be used alone or together with alkaline additives, emulsifying agent and bleaching agent.
(3)Functions, characters and usage of bleaching agent
①There are two kinds of the frequently-used bleaching agent: oxidative bleaching agent and reductive bleaching agent. Oxidation bleaching agent is also called “bleaching agent for each colors” because it is relatively safe in that it can be used not only on white fabrics but also on fabrics of other colors. As to the denatured bloodstains, oxidative bleaching agent can work on them effectively. Reductive bleaching agent is also called “bleaching agent only for white”, which can be used only on white fabrics. It should be careful about its usage. The main function of its dosage is to keep the fabrics bright and clean. Meanwhile, removing stains (bleaching pigment) is its another function. Reductive bleaching agent has the function of disinfection in the consistency of washing. However, oxidative bleaching agent can hardly have the function of disinfection under the condition of 100~300ppml/106.
②The usage of oxidative bleaching agent and reductive bleaching agent is very different: the best temperature for the former is 60℃~70℃ since too low temperature will lower its activity, while too high will do harm to fabrics and decline its capacity of removing stains due to the rapid dissolution. The best pH level for it is 10.2~10.8., and too high will lower its activity, while too low will do harm to fabrics.
③Usage: 30~50 grams of the product for each 10 kilograms of dry clothing; temperature ≧70℃; pH: 11; time:5~10mins.
(4) Acid agent
①Function: the product has the function of neutralizing free alkali, which can protect washing from yellowing and make it easier to wash together with keeping washing bright. It becomes easier to dehydrate, starch and soften stuff dealt by the product, such as overalls, tablecloth, towels and sheets.
(5)Starch powder
①The product is dissolved in low temperature and can pervade into fabrics quickly and make clothing clean, smooth, bright and easy to wash. It is suitable to starch overalls, tablecloth and table linen.
②Usage: 30~60 grams of the product for each 10 kilograms of dry clothing; temperature : 40℃~50℃.
(6)Softener
①Function: the product is composed of various kinds of compounded additives, which is able to reduce the hardness of water. Therefore, it becomes easier to wash clothing and can save more detergents. Meanwhile, it can also keep the washing from becoming dull and graying.
②Usage: the dosage of the product should be used according to the hardness of the local water, and the temperature of 40℃~50℃ is suitable.
(7)Strong synthetic alkali. The product is an alkaline compound. Its effective can be improved by working with any other detergent powder. It is suitable to wash badly-contaminated clothing by working with powerful detergent powder, and 10~30 grams of the product for each 10 kilograms of clothing;
Figure 3.7 advice for washing procedure of white cloth, napkin and cook’s uniform (pre-washing of 5 mins)
Order
|
Degree
|
Water level
|
Detergents
|
Dosage/g
|
Temperature/℃
|
Time/mins
|
1
|
Main washing
|
Low
|
Powerful cleansing powder
Additive alkali
Emulsifying agent
|
100~150
60
30~50
|
80
|
25
|
2
|
Bleaching
|
Low
|
Bleaching powder
|
70~100
|
70
|
7
|
3
|
Dehydrating
|
|
|
|
|
2
|
4
|
Rinsing
|
High
|
|
|
60
|
Twice
Once/5mins
|
5
|
Neutralizing
|
Medium
|
Acid-neutralizing agent
|
25
|
45
|
5
|
6
|
Starching
|
Low
|
Starch powder
|
40~60
|
45
|
5
|
