CN102303933A - A kind of laundry waste water recycling recycling method - Google Patents

Abstract

The invention relates to a method for recycling laundry wastewater, which is mainly used for recycling laundry wastewater discharged by an intermittent industrial washing machine which independently runs in a laundry procedure in the washing and dyeing industry. The invention adopts a mode of combining direct recycling and regeneration recycling of laundry wastewater to treat the laundry wastewater, comprising process treatment and front-end treatment. The rinsing water in the washing process flow is directly recycled according to a countercurrent rinsing mode. A washing water flow of the rinsing water in a countercurrent rinsing mode is realized, the waste water amount in a rinsing stage is reduced, and 50% -70% of fresh water consumption can be saved under the existing washing process conditions. The front-end treatment is that the waste water produced by pre-washing and main-washing in the laundry production is separately collected and treated, and the treated water is used in the pre-washing, main-washing and rinsing processes, and the reuse rate is 80%. The washing wastewater regeneration recycling system established by combining the process treatment technology and the front-end treatment technology comprehensively saves more than 80% of fresh water.

Description

A kind of laundry waste water recycling recycling method

technical field

The invention relates to a method for regeneration and recycling of laundry wastewater, which can be mainly used for regeneration and recycling of laundry wastewater discharged from intermittent industrial washing machines operating independently in the laundry industry. the

Background technique

my country is one of the 12 countries and regions that suffer from severe water shortages. According to statistics in 2008, the total amount of water resources in my country is 2,743.43 billion cubic meters, and the per capita water resources are 2,071.1 cubic meters, which is only 1/4 of the world's average level. , ranked 110th, with a total national water supply of 591.0 billion cubic meters. At the end of the 20th century, more than 400 of the more than 600 cities in the country suffered from insufficient water supply. The national water shortage reached 40 billion cubic meters, and nearly two-thirds of the cities suffered from water shortage to varying degrees. The pollution of surface water in the country is still relatively serious. The water quality of the seven major water systems is generally moderately polluted, and the problem of eutrophication in lakes (reservoirs) is prominent. The quality of groundwater is generally good, but the water quality in some areas has deteriorated. Water pollution coupled with water shortages has created a water crisis. the

Garment washing and dyeing industry is a new type of industry developed in recent years. The washing and dyeing industry, which mainly provides cleaning and maintenance services such as washing, ironing, dyeing, and darning of household clothes and public textiles, is developing rapidly. By 2009, there were about 250,000 laundries (factories) across the country, with an annual operating income of more than 50 billion yuan and more than 1.2 million employees. There are also some problems that need to be solved urgently in the washing and dyeing industry: the industry standard system is not perfect, there is a lack of skilled workers, the washing and dyeing equipment and quality monitoring methods are relatively backward, and the level of modernization is not high. There is a big gap between countries such as Japan and other countries that are at the leading level in the international laundry and dyeing industry. the

Laundry industry, as a social service industry matched with clothing, is inseparable from people's daily life. With the development of the economy and the improvement of living standards, the socialization of housework has become more extensive; the advancement of science and technology has made clothing and apparel more colorful; these factors have brought about the demand for professional laundry services, and also provided opportunities for the development of the laundry industry. Broad market space. the

There are three main ways to treat laundry wastewater: source treatment, process treatment and end treatment. the

The most fundamental way to treat laundry wastewater at its source is to do laundry without water. Commonly used laundry methods include washing and dry cleaning. The emulsification method is the most common method for water washing. The emulsification method mainly uses surfactants to moisten, disperse, solubilize and emulsify greasy substances and adhered dust to realize the purification of clothes. Dry cleaning uses organic solvents to directly dissolve the grease and oil-soluble dirt on the fabric, but cannot remove water-soluble impurities and stains. Washing with water can not only wash away the oil stains and dust on the fabric, but also change the feel of the clothes very well. Therefore, the method of dry cleaning has relatively large limitations as a means of treating the source of laundry wastewater. the

Process treatment, that is, to reduce the amount of wastewater generated during the laundry process, such as countercurrent rinsing, is a water-saving washing process technology used to remove floating colors on textiles in the dyeing and finishing process of printing and dyeing enterprises. Countercurrent rinsing is used on continuous processing devices. The direction of the textile is opposite to the direction of the textile on the processing device. For example, the direction of the textile runs from the second, third and fourth tanks after the first tank of the washing machine, and the clean water is injected from the last tank of the washing machine, such as from the first tank. The fourth tank enters and runs along the third, second and first tanks in turn. The concentration of chemicals or sewage in each washing tank increases sequentially from the fourth tank to the first tank, and the water between the washing tanks does not do any treatment along the flow direction. into the next sink. Therefore, countercurrent rinsing is a system in which both materials and water flow are continuously operated. In this system, the waste water is directly reused between the tanks, which is commonly used by printing and dyeing enterprises. In washing and dyeing enterprises, the water-saving technology of countercurrent rinsing is the tunnel washing machine. The process is to use the continuous connection of the rotating cage to turn the laundry (such as linen and towels) upside down and run from front to back, while the water flow Then the object to be washed flows from the back to the front, and the concentration of chemicals and sewage also increases gradually along the water flow from the back to the front. The items to be washed in each tumbler have sequential batches, for example, the water from the first batch of items washed in the last fresh water wash of the fourth cage is directly used for the penultimate of the second batch of items to be washed in the third cage Cleaning, the water after this washing enters the second cage for the penultimate third cleaning of the third batch of washed objects, and then discharges. Tunnel washing machine achieves two-way flow between materials and water in a semi-intermittent manner, that is, each washing is intermittent, and the laundry is automatically emptied by a mechanical device between two washes, and the water flows directly into the front cage. The waste water is also directly reused between the cages. Although the materials and water flow are operated in a semi-intermittent manner between the cages, overall the tunnel washing machine also realizes the continuous washing of materials and water, which is more efficient than the continuous washing machines of printing and dyeing enterprises. dropped. However, compared with other washing equipment in washing and dyeing enterprises, the tunnel washing machine belongs to the equipment with large production capacity, less labor and advanced production efficiency. At present, in China, due to the insufficient ability of washing and dyeing enterprises to receive orders and the connection with the work and rest of hotels, tunnel washing machines are often in a state of full production and cannot run 7×24 hours, resulting in production and water-saving efficiency and equipment design capabilities. Compared with the sharp drop, the vast majority of washing and dyeing enterprises in China use intermittent industrial washing machines that operate independently as their means of production. This type of laundry device discharges every time washing and rinsing regardless of the concentration of dirt in the water, and is no longer used. At present, the discharge of laundry wastewater from washing enterprises, small and medium-sized enterprises enter the urban sewage treatment system along with domestic sewage pipes, and large-scale enterprises discharge it after water treatment. The washing industry consumes a lot of water resources, and there is basically no reuse. In 2010, the shortage of water resources in Beijing reached 1.18 billion cubic meters per year, and the current total water consumption of the washing and dyeing industry in Beijing exceeded 100 million cubic meters per year. The water resource gap is not less than 80 million cubic meters per year. For the whole laundry process, about 50% to 70% of water can be saved in the countercurrent rinsing process under the existing technological conditions, but all problems cannot be solved, and some waste water remains to be utilized. the

The existing treatment plan for laundry wastewater is to centrally collect all wastewater, and then uniformly degrade the organic matter in the wastewater directly, and discharge it directly after reaching the national discharge standard. The main components of laundry wastewater are organic pollutants, and the terminal treatment methods of wastewater include biochemical treatment technology, physicochemical treatment technology and photocatalytic oxidation technology. Due to the centralized collection of all wastewater, the composition of the wastewater is complex, and the treatment is costly and difficult; in practical applications, the discharge of pollutants often exceeds the standard, and for laundry wastewater, the anionic surfactant (LAS) usually exceeds the standard. the

The washing process of cotton linen and uniforms generally includes three stages: pre-washing (removing floating dust), main washing (removing dirt), and rinsing (removing detergent and residual stains). For an independently operated intermittent industrial washing machine, the laundry is run in the tumbler during the three stages of the process, and each stage is realized by water inlet washing (feeding) and draining. Prewashing and main washing are performed once each, while rinsing needs to be performed N times (usually N=2-4). the

The invention combines process treatment and front-end treatment technology to regenerate and recycle laundry wastewater. The process treatment is mainly aimed at rinsing water. Because of the low concentration of detergent and dirt, it can be directly reused in the N-1th rinsing of the next batch of laundry without treatment. The countercurrent rinsing process is used to implement laundry The direct reuse of wastewater achieves the purpose of process treatment. The front-end treatment is to combine and collect the wastewater generated by the main washing and pre-washing, and it is aimed at the treatment of the wastewater with a high concentration of detergent and dirt in the laundry wastewater. The combination of these two treatments shows that the final destination of the terminal wastewater generated in the process treatment stage, that is, the countercurrent rinsing water, is used as water for the main wash; while the front-end treatment is to separate the wastewater generated by the main wash and pre-wash with chemical separation means. Collection, flocculation, centrifugal separation, filtration, etc., to separate organic matter and impurities, so that the treated water can be directly used for pre-washing water, main washing water and supplementary rinsing water. For the parts with different concentrations of dirt and detergent in the laundry wastewater, process treatment, front-end treatment and the organic combination of the two are respectively adopted to form a complete laundry wastewater regeneration and recycling system. Among them, the process treatment part can save 50% to 70% of water (related to the number of times of rinsing N), and the front-end treatment part can be reused by 80%. The total saving of fresh water consumption of the system is more than 80%. the

The properties of chemical substances in laundry wastewater are basically the same, and the treatment is highly targeted. The water of heavy pollution and light pollution is treated with front-end treatment technology and countercurrent rinsing technology respectively, and the direction of water intake is reasonable through water planning and design. The treatment effect is obvious. The water only needs to meet the production needs without affecting the product quality. The water quality can be lower than the standard discharge water and reclaimed water quality. Therefore, the process is simple, the difficulty of treatment is reduced, the investment is less, and the cost is lower. It is an effective method for water quality. the

Contents of the invention

The purpose of the present invention is to provide a method for regeneration and recycling of laundry wastewater, which can be mainly used for regeneration and recycling of laundry wastewater discharged from intermittent industrial washing machines that operate independently in the laundry process of the washing and dyeing industry. The invention adopts the method of combining the direct recycling of the laundry wastewater and the recycling recycling, and treats the laundry wastewater, including process treatment and front-end treatment. Process management The rinsing water in the laundry process is directly reused in the form of countercurrent rinsing. For the independently operated intermittent industrial washing machine, a semi-intermittent continuous flow of rinsing water is designed, and the laundry is an intermittent operation system, so as to realize the water flow of rinsing water for countercurrent rinsing and reduce the amount of waste water in the rinsing stage. In the existing laundry Under technological conditions, 50% to 70% of fresh water consumption can be saved. The front-end treatment is to separately collect and treat the waste water generated by pre-washing and main washing in laundry production, and treat it by flocculation, centrifugal separation, filtration and other methods. The treated water is used in pre-washing, main washing and rinsing, and the reuse rate reaches 80% %, the establishment of a regeneration and recycling system saves the consumption of fresh water. the

As shown in the flow chart of laundry wastewater regeneration and recycling process, the process of process governance, front-end governance and the combined laundry wastewater regeneration and recycling system is as follows: fresh water enters the final rinse of the first batch of laundry, discharge and dehydration produce waste water into 1 ^# water storage tank, and the N-1 rinsing of the second batch of washed objects uses the stored water in 1 ^# waste water tank, and so on to the first rinse, and the waste water generated by discharge and dehydration enters m ^# waste water tank for To replenish water for the main washing of the next batch of laundry, and complete the direct reuse process of wastewater from countercurrent rinsing. The front-end treatment collects the main washing and pre-washing water in the water storage tank, and after flocculation, centrifugal separation, filtration, and ultraviolet tube sterilization, it is stored in the return water tank and used as pre-washing and main washing water. If the rinsing water is insufficient, it can also be used as water. Under continuous production conditions, such a complete laundry waste water recycling system can save more than 80% of fresh water consumption.

(1) Direct reuse of rinsing wastewater: As shown on the right side of the laundry wastewater regeneration and recycling process flow chart, based on the principle of countercurrent rinsing, a semi-intermittent continuous flow of rinsing water and a system for intermittent production of the laundry are designed to make the rinsing water Without treatment, it is directly recycled to the N-1th washing of the next batch of washed objects. the

(2) Separate collection of main washing and pre-washing wastewater: As shown on the left side of the laundry wastewater regeneration and recycling process flow chart, the separate collection in actual production refers to the pre-washing and main washing stages in the laundry process of linen, uniforms, etc. Collection of discharged higher concentration contaminated laundry wastewater. The water source used in these two stages is mainly the recycled water generated by the normal operation of the laundry wastewater recycling system. Research object of the present invention: ①The actual waste water of the main washing stage ②Waste water prepared according to the dosage of detergent varieties in the main washing stage. the

(3) Flocculation: Use organic flocculants to determine reasonable flocculation conditions for laundry wastewater. the

(4) Separation: Through the screening and combination of filter materials and separation methods, the laundry wastewater can meet the requirements of regeneration and recycling. the

(5) Evaluation method of washing effect:

The evaluation method of the washing effect of the present invention is formulated with reference to FZ/T10012-1998 "Evaluation of the Ease of Decontamination of Polyester-Cotton Fabrics". the

A. Preparation of standard oil stains: ① Add 0.1g carbon black (300 mesh) to 100g of colored fabric 14 ^# engine oil, stir with a high-speed mixer (6000-7000r/min) for 10min, and store it in a jar for later use. ②For colorless white fabric, change 14 ^# engine oil to edible vegetable oil, and prepare standard oil stain under the same conditions.

B. Sample preparation of the object to be washed: take the fabric with the same fiber composition, yarn, and specification as the object to be washed (or the same 40 pure cotton poplin white cloth), cut 5 samples of 150mm×150mm, and fresh-keeping film 70mm× 3 pieces of 70mm, qualitative filter paper Φ90mm×3 sheets. the

C. Contamination of the fabric sample: place the fabric sample on top of the qualitative filter paper (its center coincides), take 0.5mL standard oil stain with a 1mL graduated pipette, and slowly drop it all at an elevation of 20mm in the center of the sample, and use a fresh-keeping Cover the oil stain with the film and press it with a weight of 50 mm in diameter and 1 kg for 5 minutes, then remove the weight and plastic wrap, let the sample stand at room temperature for 30 minutes, and wash it. Repeat this method to obtain 3 contaminated samples. the

D. Washing of contaminated samples: Wash 3 contaminated samples and 2 uncontaminated samples respectively according to the detergent formula and washing process conditions of the washing and dyeing enterprises implementing the laundry wastewater regeneration cycle system . The same washing was carried out twice, wherein the first time was washed with fresh water of the enterprise. The second time is washed with recycled water treated by the present invention. the

E. Test sample evaluation: GB250 is used to evaluate the color difference with the gray sample card for evaluating discoloration of colored fabrics, and GB251 is used to evaluate the color difference for colorless white fabrics. Color difference grade 5 is the best, grade 1 is the worst, and grade 4 is superior; the standard sample is an uncontaminated sample washed with fresh water. The color difference between the uncontaminated sample and the standard sample washed with reused water, the colored fabric and the colorless white fabric should not be lower than level 4. The color difference between the stained sample washed with recycled water and the uncontaminated sample should be equivalent to the color difference level between the stained sample washed with fresh water and the standard sample. After washing the uncontaminated samples, one is used and the other is prepared, and after three contaminated samples are washed, take the average value of the color difference to determine the color difference grade. the

The conditions of use of the above invention are as follows:

Contents of the invention (1) Direct reuse of rinsing wastewater: see the right side of the laundry wastewater regeneration and recycling process flow chart: the first batch of laundry is pumped into 1 ^# waste water tank for storage, and the second batch The N-1 rinsing of the laundry uses the water stored in the 1 ^# waste water tank, and the dewatered water is pumped into the 2 ^# waste water tank for storage, and it is reciprocated in sequence to the NM rinsing of the M batch of laundry (M-1) ^#Wastewater tank stores water, which is pumped into M ^#wastewater tank for storage by water pump for dehydration, which can supplement cooling water for main washing.

The content of the invention (2) The active ingredients contained in the main washing and prewashing wastewater are soap, strong washing powder, general washing powder, emulsifier and oxygen bleaching agent, etc., wherein the soap concentration is 0.1-3.0g/L, preferably: 0.2 -2.0g/L; strong detergent powder concentration: 0.3-5.0g/L, preferably: 0.5-3.0g/L; general detergent powder concentration: 0.3-5.0g/L, preferably: 0.5-3.0g/L; The emulsifier concentration is 0.1-2.5g/L, preferably: 0.5-2.0g/L; the oxygen bleaching agent concentration is 0.5-5.0g/L, preferably: 1.0-3.0g/L. the

Among them, the content of the invention (3) Before flocculation, the laundry wastewater is oxidized by oxygen bleaching agent at 60°C-90°C for 10-20 minutes, and then the pH is adjusted with polymaleic acid. The total volume of the solution is 1000ml. It is: flocculant 1-2mg/ml, pH value: 5-7, preferably: flocculant: 1.2-1.7mg/ml, pH value: 5-6; ②The flocculation condition of strong washing powder is: flocculant: 1- 2mg/ml, pH value: 8-10, preferably: flocculant: 1.2-1.7mg/ml, pH value: 8-9; ③ emulsifier flocculation conditions: flocculant: 1-2mg/ml, pH value: 5 -7, preferably: flocculant: 1.0-1.5mg/ml, pH value: 5-6; ④ The general washing powder flocculation conditions are: flocculant: 0.5-3mg/ml, coagulant: 0.1-0.5mg/ml, pH value: 5-7, preferably: flocculant: 0.5-2.5mg/ml, coagulation aid: 0.1-0.3mg/ml, pH value: 5-6; ⑤ strong washing powder + soap + emulsifier selected flocculation conditions For: flocculant 1-3.5mg/ml, coagulant: 0.1-0.5mg/ml, pH value: 5-7, preferably: flocculant: 1.5-3.0mg/ml, coagulant: 0.1-0.3mg/ml ml, pH: 5-6. the

The content of the invention (4) Due to the different sizes of flocs produced by flocculation, the combination of filter materials with different pore sizes can increase the separation efficiency, improve the separation effect, and reduce the cleaning frequency of the filter. The separation materials selected in the present invention are PP cotton filter element, 0.1-0.2 micron ceramic filter element and 0.05 micron folded membrane filter element; the separation method adopted is to separate the floc liquid through a centrifuge first, and then use a diaphragm pump to send the separated clear liquid into the In the following three-stage filtration device: the first stage uses PP cotton filter element, the second stage uses ceramic filter element with 0.1-0.2 micron pore size, and the third stage uses 0.05 micron pore size polytetrafluoroethylene folded membrane filter element for dynamic filtration. the

The content of the invention (5) Use different detergents to wash the cloth stained with oil under the conditions of fresh water and regenerated circulating water. The colored fabric adopts GB250 to evaluate the color change and the gray sample card to evaluate the color difference, and the colorless white fabric adopts GB251 to evaluate the staining Use the gray sample card to evaluate the color difference, and the color difference grades are all above grade 4. the

The beneficial effects of the present invention are:

(1) Adopt the front-end treatment technology route to collect and treat the wastewater from the main washing and pre-washing processes separately. Because the properties of the chemical substances in the laundry wastewater are basically the same, the treatment is highly targeted and the effect is obvious. The reused water treated by the method of the present invention only needs to meet the laundry requirements without affecting the quality of the laundry, and the water quality can be lower than the quality of the discharged water and regenerated water. Therefore, the process is simple, the difficulty of treatment is reduced, the investment is less, and the cost is lower. An effective way to divide water quality. the

(2) The use of process treatment technology can reduce the amount of wastewater produced in the laundry process, such as countercurrent rinsing. For the entire laundry process, the countercurrent rinsing process can save 50% to 70% of water under the existing process conditions. The laundry wastewater treated by the front-end treatment technology is mainly reused in the pre-washing and main-washing stages, and 80% of it can be reused. The laundry wastewater regeneration and recycling system established by the combination of process treatment and front-end treatment technology comprehensively saves more than 80% of fresh water consumption. the

(3) In the recycled water separated by flocculation with organic flocculants, there are no metal ions such as iron and aluminum produced after flocculation with inorganic flocculants. When oxygen bleaching agents are used in the main washing stage, cotton fabrics (containing cellulose fibers) can be avoided. Fabric) produces oxygen bleaching holes and damage. the

(4) adopt different washing agents to wash the cloth that is stained with oil under two kinds of water situations of fresh water and recycled water after the process of the present invention, and the color difference grades are all above grade 4. It shows that the recycled water treated by the method of the present invention is used to wash the fabric, which can achieve the same washing effect as fresh water. the

Description of drawings

Accompanying drawing is the technological flow chart of regeneration and recycling process of laundry wastewater of the present invention

The following examples further illustrate the present invention, but the present invention is not therefore limited to the scope of the specific examples. the

Example 1: Flocculation and separation of main wash preparation wastewater

According to the method of the content of the invention (2), weigh 2.0g of general washing powder, add 870ml of water, heat to 70°C, add 1.0g of color bleaching powder, dissolve and keep warm for 15 minutes, add 1.0ml of polymaleic acid after cooling, add 5g after stirring /L cationic organic polymer flocculant E 130ml, the total volume is about 1L, after stirring, let it stand for 15 minutes, use qualitative filter paper as the filter material to statically filter, recover about 850ml of filtrate, test the pH value of the filtrate is 6, and the light transmittance is 98.0%, the turbidity is 4.83NTU, and the surface tension is 35.6mN/m. Example 2: Flocculation and separation of main wash wastewater for sports socks

According to the method of the content of the invention (2), take 7 sports socks weighing 100g, weigh 2.0g of general-purpose washing powder, add 870ml of water, put them into the sports socks, stir and heat to 70°C, add 1.0g of oxygen bleaching powder to dissolve, stir and keep warm for 15 minutes , take out the sports socks, the remaining raffinate is about 770ml, after cooling, add 1.0ml polymaleic acid and stir, then add 20.0g/L cationic organic polymer flocculant E 125ml, stir and stand for 15 minutes, then add 1.0g/L polymaleic acid Coagulant aid 150ml, total volume about 1L, leave standstill for 10 minutes after stirring, carry out floc separation according to the method of content of the invention (4), reclaim filtrate about 900ml, measure filtrate pH value is 6-7, light transmittance is 96.7% , the turbidity is 5.93NTU, and the surface tension is 61.4mN/m. the

Example 3: Flocculation and separation of single detergent components in main wash preparation wastewater

Weigh 1.25g of soap according to the method of the content of the invention (2), dissolve it in 700ml of water at 50°C, heat to 70°C, add 1.0g of color bleaching powder, dissolve and keep warm for 15 minutes, add 1ml of polymaleic acid after cooling, and stir for 10 minutes Minutes later, add 300ml of cationic organic macromolecule flocculant E of 5g/L, add up to about 1L, leave standstill for 15 minutes after stirring, filter with qualitative filter paper, measure filtrate pH value is 6, light transmittance is 99.0%, turbidity is 4.05NTU, the surface tension is 65.9mN/m; Weigh 2.0g of strong washing powder, dissolve it in 720ml of water, heat to 70°C, add 1.0g of color bleaching powder, dissolve and keep it for 15 minutes, add 0.5ml of polymalay after cooling Acid, after stirring for 5 minutes, add 280ml of cationic organic polymer flocculant E of 5g/L, totaling about 1L, after stirring, let stand for 15min, then filter with qualitative filter paper, measure the pH value of the filtrate to be 8-9, and the light transmittance is 100.0%, the turbidity is 0.95NTU, and the surface tension is 53.4mN/m; weigh 1.5g of emulsifier, dissolve it in 780ml water, heat to 70°C, add 1.0g of color bleaching powder, dissolve and keep it for 15 minutes, add 2.0 ml polymaleic acid, after stirring for 10 minutes, add 220ml of 5g/L cationic organic polymer flocculant E, the total volume is about 1L, after stirring, let stand for 15 minutes, filter with qualitative filter paper, and measure the pH value of the filtrate to be 5-6 , the light transmittance is 97.2%, the turbidity is 5.38NTU, and the surface tension is 55.2mN/m. the

Example 4: Detergent formula preparation main wash wastewater flocculation separation

According to the method of the content of the invention (2), weigh 1.25g of soap, 2.0g of strong washing powder, and 1.5g of emulsifier, dissolve them in 700ml of water at 50°C, heat up to 70°C under stirring, add 1.3g of oxygen bleaching agent, and dissolve Then keep warm for 15 minutes, add 2.5ml polymaleic acid after cooling, add 5g/L cationic organic polymer flocculant E 300ml after stirring for 10 minutes, the total volume is about 1L, let it stand for 15 minutes after stirring, and use qualitative filter paper Filtrate and recover about 870ml of the filtrate. The pH value of the filtrate is 5, the light transmittance is 99.2%, the turbidity is 3.98NTU, and the surface tension is 67.5mN/m. the

Example 5. Flocculation and separation of main wash wastewater for sports socks detergent formula

According to the method of the content of the invention (2), take 7 sports socks weighing 150g, weigh 1.5g of strong washing powder, 1.0g of soap, and 1.0g of emulsifier, dissolve them in 1L of water at 50°C, add the sports socks, and stir Raise the temperature to 70°C, add 134ml of dissolved 10g/L oxygen bleaching agent, stir and keep warm for 15 minutes, take out the sports socks, the remaining residual liquid is about 950ml, add 2.5ml of polymaleic acid after cooling, add 20g/L after stirring for 10 minutes Cationic organic macromolecular flocculant E 200ml, 1g/L coagulant aid 325ml, total volume about 1.5L, leave standstill for 15 minutes after stirring, carry out floc separation by the method of content of the invention (4), reclaim filtrate 1.3L , the measured filtrate pH value is 5-6, the light transmittance is 98.1%, the turbidity is 5.82NTU, and the surface tension is 56.0mN/m. the

Embodiment 6. washing effect evaluation

According to content of the invention (5) A, adopt edible vegetable oil to prepare standard greasy dirt; Prepare washed object sample according to content of invention (5) B with 40 pure cotton poplin white cloth; Contaminate sample according to content of invention (5) C; SUMMARY OF THE INVENTION (5) Item D is for washing. Wherein the detergent formulation and the washing process conditions are the same as in Example (4) of the present invention. Laboratory deionized water is used for the first washing, and water treated by the regeneration cycle method of the present invention is used for the second washing as the water for pre-washing, main washing and first rinsing. Use laboratory deionized water as water for the second and third rinses, and dry the fabric after washing. Use GB251 to evaluate the color difference with the gray sample card for staining, and the color difference between the non-contaminated sample cloth washed with laboratory deionized water and the non-contaminated sample cloth washed with water treated by the present invention is 5 grades. The color difference between the non-stained sample cloth and the stained sample cloth washed with deionized water in the laboratory is 4-5 grades. The color difference between the non-stained sample cloth and the stained sample cloth washed with the water treated by the present invention is 4-5 grades. The color difference between the uncontaminated sample cloth washed with laboratory deionized water and the stained sample cloth washed with the treatment water of the present invention is 4 grades. The color difference between the unwashed swatches and the unwashed and unstained swatches was 2-3 grades. It shows that the detergent formula and washing process are effective for the washing of artificially prepared standard oil stains. Different washing water has no obvious difference in washing effect. The cleaning effect of the treated water in the invention is equivalent to that of laboratory deionized water, and meets the requirements of the laundry industry. the

Example 7: Washing of linen such as bed sheets and quilts (as shown in the flow chart of the regeneration and recycling process of laundry wastewater) Washed object: linen 80Kg

1. Pre-washing: Take 350L of water from the return tank, and wash for 3 minutes after reaching the water level. the

2. Drain 200L to the sewage tank. the

3. Main wash: Take 100L water from the return tank and add steam. the

When the steam reaches 70°C, add 700g of color bleaching powder and wash for 15 minutes;

Fourth, the gradual cooling method:

1. Do not drain water, first take 200L of water from 3 ^# waste water tank;

2. After rotating for 2 minutes, drain 250L to the waste water tank;

3. Then take 200L of water from the 3 ^# waste water tank and 50L of water from the return water tank, turn it on for 2 minutes, and drain 300L to the waste water tank.

5. The first rinsing: Take 300L of water from 2 ^# waste water tank, run for 3 minutes, drain and dehydrate 400L to 3 ^# waste water tank.

Sixth, the second rinse: take 350L water from 1 ^# waste water tank and turn it for 3 minutes, drain 250L to 2 ^# waste water tank.

7. The third rinse: Add 200L of fresh water, heat at 35°C-45°C, add neutralizing acid agent: 300g, turn for 3 minutes, drain and dehydrate at high speed, and drain 300L into 1 ^# waste water tank.

Eight, linen out of the machine

Balance calculation of intake and drainage:

The waste water tank receives 200L of pre-wash sewage, and 250L+300L of main wash sewage twice, totaling 750L;

Return water tank: receive 600L (750×80%) of regenerated circulating water;

1 ^#Wastewater tank receives the third rinsing drainage and high-speed dehydration production water totaling 300L. The second rinsing needs to take 350L of water from the 1 ^# waste water tank, and the gap of 50L is replenished from the return water tank;

2 ^#Waste water tank receives the second rinsing drainage 250L. For the first rinsing, 300L of water should be taken from the 2 ^# waste water tank, and the gap of 50L should be replenished from the return water tank;

3 ^#Waste water tank receives the first rinse row and dehydrates 400L. 450L of cooling water for the main wash twice, take 400L of water from the 3 ^# waste water tank, and replenish 50L of water in the return water tank;

The main wash takes 100L of water from the return tank, add three times of supplementary water 3×50L = 150L, plus pre-wash takes 350L of water from the return tank, and takes a total of 600L of water from the return tank, which is balanced with the 600L of recycled water treated by the return tank. the

The water circulation operation of each part of the laundry wastewater recycling system is basically in a balanced state. Among them, 200L of fresh water is taken, and 80Kg of linen is dehydrated with more than 60% of water, which is 50L, and the remaining 150L is consumed by flocculation, centrifugal separation, filtration and partial leakage and evaporation. the

If fresh water is used in each stage and discharged directly without reuse, pre-wash 350L, main wash 550L, and three rinses (300+350+200) total 850L. The 80Kg linen uses 1750L of fresh water. Save 1550L of fresh water, saving 88.6% of water. the

Use the same batch of linen to wash with fresh water according to the above-mentioned washing process and wash with this embodiment of the present invention. The color difference between the two kinds of linen is evaluated according to GB251 with the gray scale card for staining, and the color difference grade is 4- 5, indicating that the washing effect meets the requirements. the

Claims (8)

1. the method for a laundrywastes recycling utilization mainly can be used for washing the recycling utilization of dying the laundrywastes of the intermittent type industry washer discharging of independent operating in the industry laundry operation.

2. what adopt according to the said method of claim 1 is that process is administered and front end improvement array mode.Process is administered the rinse water in the laundry process flow process, carries out the direct reuse of waste water by the countercurrent rinsing form.Front end is administered prewashing and main waste water single collection improvement of washing generation in the production of will doing washing, and handles through methods such as flocculation, centrifugation, filtration, ultraviolet-sterilizations, and the water after the improvement is washed till in the rinsing and uses prewashing, master.

3. administer according to the process in the said method of claim 2 and be: be principle with the countercurrent rinsing; The continuous flow of a rinse water semi-batch of design; The system of substrate batch production makes rinse water not treated, and direct reuse is to the N-1 time washing of next batch substrate.

4. the effective constituent that the master washes, prewashing waste water is contained in administering according to the said method front end of claim 2 is that soap, powerful washing powder, general washing powder, emulsifying agent and oxygen float agent etc., and wherein soap concentration is 0.1-3.0g/L, and is preferred: 0.2-2.0g/L; Powerful washing powder concentration is: 0.3-5.0g/L, and preferred: 0.5-3.0g/L; General washing powder concentration is: 0.3-5.0g/L, and preferred: 0.5-3.0g/L; Emulsifier concentration is 0.1-2.5g/L, and is preferred: 0.5-2.0g/L; It is 0.5-5.0g/L that oxygen floats agent concentration, preferred: 1.0-3.0g/L.

5. according to claim 2,4 said methods; Float agent under 60 ℃ of-90 ℃ of conditions oxidation 10-20 minute through peroxide earlier before the laundrywastes flocculation; Regulate pH with polymaleic acid again; Overall solution volume is 1000ml; 1. the selected flocculating conditions of soap is: flocculation agent 1-2mg/ml; PH value: 5-7, preferred: flocculation agent: 1.2-1.7mg/ml, pH value: 5-6; 2. powerful washing powder flocculating conditions is: flocculation agent: 1-2mg/ml, and pH value: 8-10, preferred: flocculation agent: 1.2-1.7mg/ml, pH value: 8-9; 3. the emulsifying agent flocculating conditions is: flocculation agent: 1-2mg/ml, and pH value: 5-7, preferred: flocculation agent: 1.0-1.5mg/ml, pH value: 5-6; 4. general washing powder flocculating conditions is: flocculation agent: 0.5-3mg/ml, and coagulant aids: 0.1-0.5mg/ml, pH value: 5-7, preferred: flocculation agent: 0.5-2.5mg/ml, coagulant aids: 0.1-0.3mg/ml, pH value: 5-6; 5. powerful washing powder+soap+selected flocculating conditions of emulsifying agent is: flocculation agent 1-3.5mg/ml, and coagulant aids: 0.1-0.5mg/ml, pH value: 5-7, preferred: flocculation agent: 1.5-3.0mg/ml, coagulant aids: 0.1-0.3mg/ml, pH value: 5-6.

6. according to claim 2,4,5 said methods, parting material is the cotton filter core of PP, 0.1～0.2 micrometer ceramics filter core and 0.05 micron folded membrane filter core; Separate mode separates through whizzer earlier for flocculation liquid; Clear liquid after the separation uses surge pump that it is sent in the following filtration unit: the cotton filter core of first step PP wherein; The ceramic element of the second stage 0.1～0.2 micron pore size, the tetrafluoroethylene folded membrane filter core of the third stage 0.05 micron pore size.

7. adopt different washing composition under fresh water and two kinds of situation of reprocessing cycle water, to wash and speckle with smeary cloth; Colored fabric adopts GB250 evaluation variable color to evaluate aberration with gray scale; Colourless incandescence thing adopts GB251 grey scale for assessing staining of colour evaluation aberration, and the aberration grade is all more than 4 grades.

8. according to claim 2,5 said methods, flocculation agent is: cationic organic polymer coargulator (molecular weight: 500-200 ten thousand), coagulant aids is: sodium polyacrylate, pH regulator agent are polymaleic acid.

Images