Chinese name: polyacrylamide 
Chinese alias: flocculant on the 3rd; referred PAM; polyacrylamide is called Three coagulant; polyacrylamide into anionic polyacrylamide; cationic polyacrylamide; non-ionic polyacrylamide; zwitterionic polyacrylamide; English name; PAM (acrylamide)
English Name: Polyacrylamide absorbent Gel; Polyacrylamide solution; Acrylamide resin (low M.Wt .; Acrylamide resin (high M.Wt.); Acrylamide gel solution; Polyacrylamide, hydrolyzed; Polyacrylamide; PAM
CAS: 9003-05-8 Formula: (C3H5NO) n Molecular Weight: 71.07
Acronym: PAM is polyacrylamide acrylamide (AM) monomer by free radical initiated polymerization of a water-soluble linear polymer, insoluble in most organic solvents, has good flocculation resistance, can be reduced between the liquid friction, according to the ionic character of sub-divided into non-ionic, anionic, cationic and amphoteric four types.
Mesh size or thickness of the material means, the mesh is the number of squares per unit area generally is defined as the number of how many there are in the area of cell 1 inch by 1 inch, the mesh sieve that is the number. Such as 600 mesh per square inch 600 square mesh, mesh polyacrylamide 20 mesh to 80 mesh, is between 0.85mm ~ 0.2mm, which is granular polyacrylamide mesh size, powder like polyacrylamide mesh size can be controlled at about 100 mesh, mesh the greater the more readily soluble polyacrylamide, polyacrylamide mesh size alone is unable to measure the quality of the product!
Polyacrylamide (PAM) to water-soluble polymers, insoluble in most organic solvents, has good flocculation, can reduce the frictional resistance between the liquids.
As of polyacrylamide (PAM) expanding operational needs of the market and the industry export growth, China's polyacrylamide (PAM) industry is running usher in a new development opportunity.
1, the size of the floc: the floc is too small to affect drainage rate, floc floc constraints make much more water and reduce the mud biscuits. After selecting the molecular weight polyacrylamide can adjust the size of floc.
2, sludge characteristics: The first point to understand the source of sludge characteristics and composition, proportion. Depending on the nature of the different sludge can be divided into two kinds of organic and inorganic sludge. CPAM for disposal of biosolids, the relative anionic polyacrylamide flocculant for mineral sludge, strong alkaline when cationic polyacrylamide, anionic polyacrylamide and should not be used when very acidic, solid content high amount of sludge is usually polyacrylamide is also large.
3, floc strength: floc under shear should insist on steady without breaking. Advances in molecular weight polyacrylamide or select the appropriate molecular structure to help improve floc stability.
4, the degree of ionic polyacrylamide: for dewatered sludge, flocculant available ions of different small test do first through the selection, select the best suitable polyacrylamide flocculant thus being able to obtain the best effect, but also make dosage minimal cost savings.
5, dissolved polyacrylamide: Good to be fully dissolved flocculation. Sometimes it needs to speed up the dissolution rate, when the concentration of progress can think of polyacrylamide solutions.
PAM and PAC can use it?
In fact, when the usual treatment of sewage, some water, a single flocculant is not up to the effect, you must use the two in combination, the use of inorganic coagulant PAC and polyacrylamide flocculant sewage treatment complex will achieve better effect, but to pay attention when a drug-order, order is not correct, but also fail to effect.
Polyacrylamide flocculant used in combination with other sequential method added:
When using composite flocculant must pay attention to adding sequence and dosing intervals! PAC and PAM is to allow PAC to be used in combination and after completion of the charge / colloidal stability formation of small floc, and further increase the floc size, which facilitates ample precipitation. Because PAC PAC response time is very short, so the added need intensive mixing, PAM longer duration of action, mixed note after the first strong weak - the first strong to weak after mixing in order to avoid destruction of floc! Polyacrylamide flocculant belong, belong PAC coagulant, under normal circumstances is to add coagulant together with polyacrylamide, but to be safe, it is recommended that you add by experimental results to determine the order! Dosing point, dosing quantity, dosing and mixing intensity required time determined experimentally, remember do not put them two agents used together, otherwise it will affect the results, increasing the cost.
Polyacrylamide flocculant failure judging method:
Often encounter a lot of sewage treatment plants, especially in the southern regions, humid climate, some of the sewage plant because polyacrylamide stacking port for a long time or the packaging does not absorb moisture caking truss cause for polyacrylamide flocculant agglomerate situation many people have questions, it is not failure, and also can you then, in fact, as in this case as long as you can take it dissolved open, solution viscosity, there is no failure, but after polyacrylamide agglomeration is difficult to dissolve open, in fact, also means a waste of resources. Different types of polyacrylamide real shelf life is a big difference, and this and its associated structures, relatively speaking, anionic polyacrylamide valid longer time points, a cationic polyacrylamide general state of our shelf life of 1 year . Beyond this period, it is regarded as more than shelf life. There is the risk of failure.
Polyacrylamide failure can be judged from two aspects, one is the viscosity reduction, two flocculation deteriorates.
1, flocculation: PAM allows suspended material by charge neutralization, bridging adsorption, since flocculation.
2, adhesion: through mechanical, physical and chemical effects, since adhesion.
3, lowering resistance: PAM can effectively reduce fluid friction, water resistance with traces of PAM can drop 50-80%.
4, thickening: PAM have a thickening effect in neutral and acid conditions, when the PH value above 10 PAM easy hydrolysis. When semi-mesh structure, thickening more obvious.
PAM usage instructions:
1, the number of washing with the use of cationic polyacrylamide can be set between thirty kilograms to one hundred and ten kilograms; the amount of the chemical industry waste water is generally between fifty to one hundred and twenty kilograms; dyeing industry wastewater and paper industry wastewater difficult to deal with, should increase the number of use, use the number provided in the one hundred to three hundred kilograms more reasonable, electroplating wastewater industry and general industrial water are generally not more than fifty kilograms. Note the number of the number :( these types of industries are using thousands of tons of wastewater each).
2, sewage treatment methods depending on the mud off with a flocculant is not the same.
If the process the body uses biochemical methods, ie sludge dewatering (which may contain part of the primary sedimentation mud), just as the sludge dehydrating agent of cationic PAM can.
If the process main use of physical and chemical methods, such as an enhancement, loading magnetic separation process, the general is to add PAC quenched, and then add an anionic flocculant, and finally add the cationic flocculant dehydration. Specific dosage should be based on wastewater quality.
There are also many sewage treatment station, sludge dewatering directly added to PAC or other inorganic flocculants, the in frame filter, especially electronics factory or a small sewage treatment plant used widely.
PAM at the time as the sludge dehydrating agent used generally at 0.1% and the ratio of water - 0.2%. Dissolved into a glue-like liquid later, and then added to the sludge mixing investment process.
And sludge ratio is generally 5% --10%, and some less, this should be determined according to the concentration of the sludge, it is best to determine the optimal dosage and use of models through field experiments beaker. Different kinds of sludge, the different agents, the treatment effect of different equipment, different management levels, the sludge is different.
3, the sewage treatment plant with a cationic polyacrylamide as sewage sludge dewatering operations agent. In the process of communicating with clients, the clients often asked in the process of sewage treatment sludge dewatering, sludge dewatering agent dosage problems. To know relatively accurate dosage sludge dewatering problems, first understand these parameters, the moisture content of the sludge, mud cake moisture content, into the mud, into the dose, dispensing concentration.
Sludge moisture content: the percentage of moisture contained in the sludge weight and sludge ratio is referred to the total weight of the moisture content of the sludge.
Cake moisture content: That is a percentage off sludge cake moisture contained in the weight ratio of the total weight of the sludge cake moisture content is called.
Also through the following formula for computing
1, dosage mg / L = dosing quality / process water / Pharmaceuticals concentration
2, treated water dosage dose = treated water m3 / h * dosage g / m3
3, dry mud = treated water * [(1 - sludge moisture content) / (1 cake moisture content)]
4, pharmaceutical consumption per ton of dry mud g / m3 = dosage / dry mud
The calculated results of the above error may be relatively large, for reference only make sewage running. The actual consumption of the dose to be actually test machine operators.
Polyacrylamide general classification:
Anionic polyacrylamide (APAM) Product description:
Anionic polyacrylamide (APAM) appearance of white powder, molecular weight of from 6 to 25 million
Water soluble, can be dissolved in water in any proportion and insoluble in organic solvents. Effective PH value in the range of 4-14, in a neutral alkaline medium showed the characteristics of high-polymer electrolyte, the electrolyte salt sensitive, with high metal ion can be cross-linked into an insoluble gel.
Industrial wastewater treatment: For suspended particles, representing a high concentration of particles with a positive charge, water PH value is neutral or alkaline water, iron and steel plant wastewater, electroplating factory wastewater, wastewater metallurgy, coal washing waste such as sewage treatment, the effect The best. Drinking water treatment: a lot of water from the river water plant, sediment and mineral content is high, more turbid, though filtered through the precipitate, still can not meet the requirements, needs adding flocculants, inorganic coagulant dosage is 1 / 50, but the effect is several times the inorganic flocculants, for serious organic pollution of the river water can be inorganic coagulant and cationic polyacrylamide with the use of better. Now dosing anionic polyacrylamide, starch particle coagulation and sedimentation, and then the precipitate was filter press filter press into a pie, can be used for feed, ethanol plants may be used alcohol anionic polyacrylamide dehydration, pressure filtration for recycling . Settlement for the river mud. Dry strength agents for paper.
For paper chemicals, aid rate agent. In the paper before the opening ceremony pump slurry storage tank with traces of PAM-LB-3 anionic polyacrylamide can water filler and fines retention in the online 20-30%. Per ton of pulp can save 20-30kg.
Example: In the coal washing process produces a lot of waste water discharged directly pollute the environment, must Simcheong after recycling, recycling water and coal, but also of great value, but by natural sedimentation, time-consuming, but the water is not clear.
In addition, the anionic polyacrylamide in incense industry applications are increasingly popular, anionic polyacrylamide Features: with good solubility, high viscosity, high toughness, combustibles (less) smoke, burning odor, no drugs, and other characteristics; product performance and stability, to avoid other plants common starch powder and because of origin, at different times, bonding of varying quality, in the incense industry production requires repeated testing recipes, product quality so as to avoid destabilizing phenomenon; incense products look smooth, good shape, not broken; particularly its pasting of cold water, no cooking paste, the material directly mixture evenly, add water, stirring can produce, and the material is mixed with water for a long time will not be placed dry and hard material phenomenon can not be used effectively save energy and facilitate the production operations.
Effect: the use of this product made of incense blanks (incense products) appearance of smooth, no break, no mildew, bending and strong, good product fineness, bake sun does not fade, time enough to ignite combustible good, too iron chainring no "decapitation" flame conducive mosquito play an active ingredient dissipation rate increase and reduce losses in the drying process finished at the same time, can greatly reduce labor intensity and improve work efficiency. In addition, the product of environmental pollution, to meet environmental protection aspects of the product requirements.
Economic benefits: the use of this product can reduce raw material costs 5-12%, 20-30% energy saving.
Cationic polyacrylamide (CPAM) Product Features:
Cationic polyacrylamide (CPAM) appearance of white powder, ion of from 20% to 55% good water solubility, can be dissolved in water in any proportion and insoluble in organic solvents. It was high polymer electrolyte characteristics for negative charge and organic matter-rich wastewater treatment. Suitable for high dyeing, paper, food, construction, metallurgy, mineral processing, coal, oil, aquatic products processing industry and other fermented organic colloid content of waste water treatment, especially for urban sewage, sludge, paper sludge and other industrial dewatering sludge.
Non-ionic polyacrylamide series polymer is a linear low ion degree of high molecular weight. Because of its particular group, they have given it flocculation, dispersion, thickening, bonding, deposition, gel, colloid stabilizing effect. Sewage treatment agent: When suspended sewage acidic, nonionic polyacrylamide flocculant as more appropriate. Then PAM adsorption bridging role play, the suspension of particles flocculation sedimentation, to purify sewage purposes. It can also be used for water purification, and in particular with the use of inorganic coagulant in water treatment works best.
1, widely used in industrial wastewater treatment, the suspended particles, coarse, high concentrations of positively charged ions, water, PH value is neutral or alkaline water, iron and steel plant wastewater, wastewater metallurgy, coal washing waste water sewage treatment best.
2, for the petroleum industry, oil, drilling mud, waste mud treatment, to prevent water channeling, reduced friction, enhanced oil recovery, EOR has been widely used.
3, for textile sizing agents, serous stable performance, down less pulp, fabric breakage rate is low, clean cloth.
4, for the paper industry. One is to increase filler and pigment retention rate; second is to improve the strength of paper (including dry strength and wet strength). Also, it can improve the tear resistance of paper and porous, so as to improve the visual and print performance, but also for the packaging of food and tea.
Zwitterionic polyacrylamide is a cationic vinyl amide monomer is acrylamide and vinyl monomers, hydrolyzed copolymerization. The molecular chains of both positive charge, negative charge there zwitterionic irregular polymers.
Polyacrylamide widely used:
1) for sludge dewatering can choose the appropriate model of the product according to the nature of the sludge, the sludge can be effective prior to entering the filter press sludge dewatering, dehydration, a large floc, when non-stick cloth, filter press is not scattered, flow thick mud cake, dehydration, high efficiency, the cake moisture content below 80%.
2) for domestic sewage and organic wastewater treatment, this product is equipped or alkaline medium showed a cationic, so that the sewage effluent suspended particles with a negative charge by a flocculation, clarification is very effective. Such as the production of grain alcohol wastewater, wastewater, urban sewage treatment plant wastewater, wastewater, monosodium glutamate factory waste water, sugar water, organic content wastewater, waste feed, textile printing and dyeing wastewater with cationic than with anionic polyacrylamide, nonionic polyacrylamide or inorganic salts effect several times or several times higher, because such waste water generally negative charge.
3) used in river water as water treatment flocculant tap water, with less effect, low cost, especially inorganic flocculant use better, it will become the rule tap the Yangtze River, Yellow River and other watersheds Factory efficient flocculant.
4) papermaking enhancers and other additives. Improve retention rates, the strength of the paper fillers, pigments and the like.
5) After learning aids used in oil fields, such as clay anti-swelling agent, oil acidification thickening agent.
6) for textile sizing agents, serous stable performance, down less pulp, fabric breakage rate is low, clean cloth.
Packaging and storage of the product is nontoxic, pay attention to moisture, rain, avoid sun exposure. Storage: 2 years, 25kg paper bag (lined with plastic bags of plastic coated outer kraft paper bags).
PAM can be applied to a variety of wastewater treatment (for sewage treatment polyacrylamide is generally divided into two processes, one polymer electrolyte and the particle surface charge neutralization; the second is a long-chain polymer electrolyte and particles frame bridge formation of floc. The main purpose of flocculation by adding polyacrylamide sludge in small suspended particles and colloidal particles coalesce into coarse floc. With increasing floc settling velocity increased. thereby Better by filter press mud, and then to deal with environmental protection requirements, dry mud Sinotrans incinerated.) PAM molecular weight by a few million to tens of millions of high-molecular water-soluble organic polymer is formed between the particles larger floc and the resulting huge surface adsorption. Currently polyacrylamide representative polyacrylamide polymer are: nonionic polyacrylamide (abbreviated NPAM, the molecular weight of 800-1500 million), anionic polyacrylamide (abbreviated APAM, the molecular weight of 800-2000 million), cationic polyacrylamide (abbreviated CPAM, the molecular weight of 800-1200 million, or ions of 10% -80%). The amount is generally the amount of wastewater to two millionths of a millionth. Thus, mainly through the synthetic form.
Preparation: Firstly, the oxidation-reduction reaction system, azo compounds and auxiliary agents initiator compound consisting of an initiator system, acrylamide (AM) and acryloyloxyethyl trimethyl ammonium chloride (or DMC, DMAAC) as raw materials, through aqueous solution radical copolymerization, synthetic cationic polyacrylamide (CPAM). Adding a certain amount of acrylamide in the reactor, acryloyloxyethyl trimethyl ammonium chloride, urea and deionized water, stir with 2mol / L of H2SO4 to adjust the pH to the desired value, which leads to N2 bubbling 30min, adding a certain amount of (NH4) 2S2O8, CH3NaO3S.2H2O and azo compounds initiate the polymerization reaction, the reaction is stopped when the sticky liquid through N2, the reaction was continued to give a white transparent colloid after 2h, the colloid under dried to constant weight at 60C and pulverized to obtain a cationic polyacrylamide flocculant.
Polyacrylamide integrated areas:
PAM application in water treatment industry including raw water treatment, sewage treatment and industrial water treatment three aspects. In the original water treatment, PAM and activated carbon used in conjunction, can be used to unite and clarify particles suspended in the water of life; in wastewater treatment. PAM can be used for sludge dewatering; in industrial water treatment, PAM is mainly used as pharmaceutical formulations. In the original water treatment, organic flocculants PAM instead of inorganic flocculants, without alteration settling tank, water capacity can be increased by 20%. Industrial wastewater treatment, especially for suspended particles, coarse, high concentrations of particles with a positive charge, water PH value is neutral or alkaline water, iron and steel plant wastewater, electroplating factory wastewater, wastewater metallurgy, coal washing waste water sewage treatment the best results. In sewage treatment, the use of PAM can increase the utilization rate of water reuse cycles.
Petroleum oil field
Oil mining, PAM is mainly used for drilling mud materials and improve aspects of oil recovery rate, widely used in well drilling, completion, cementing, fracturing, enhanced oil recovery and other mining operations in the oil field, with thickening, fluid loss, flow variable adjustment, gelling, diversion, profile control and other functions. At present, China has entered the oil exploration in the late, in order to improve oil recovery, improve water flow rate ratio, making recovery in oil content was increased. Because of the special geological conditions, the Daqing Oilfield and Shengli Oilfield has begun extensive use of polymer flooding technology.
PAM is widely used in the papermaking art resident agent, filter aid, all of the agents. Its role is to improve the quality of the paper, pulp dewatering improve performance, increase fines and filler retention, reduce raw material consumption and environmental pollution. The effect of PAM used in papermaking depends on the activity of its average molecular weight, ionic nature, ionic strength, and other copolymers. Nonionic PAM is mainly used to improve the pulp was filtered and increase dry paper strength, improve retention of fiber and filler; anionic copolymer is mainly used for dry and wet paper reinforcing agent and resident agent; cationic copolymer main for papermaking wastewater treatment and filter aids, in addition to improving filler retention and it has a good effect. In addition, PAM also used in papermaking wastewater treatment and fiber recovery.
In the textile industry, as a textile sizing agent after PAM process, finishing agents, can generate supple, wrinkle-free, mold-resistant protective layer. Use of its hygroscopic characteristics, can reduce the breakage rate of spinning yarn; after PAM for treatment agent to prevent static electricity and flame retardant fabrics; used as auxiliaries, PAM can make products for adhesion to a large, bright high, also can be used as bleaching non-silicone polymer stabilizers; in addition, PAM can also be used for purification of textile printing and dyeing wastewater.
In the field of mining, coal washing, sedimentation by PAM flocculants to promote mining, coal washing water recycling solids, make the water clear, and recycling of useful solid particles, to avoid pollution to the environment; in the sugar industry, PAM can accelerate the juice in the fine particles sink, promote filtering and improve filtrate clarity degree; in the breeding industry, PAM can improve water quality, increase the light transmittance of water, thereby improving water photosynthesis; in the pharmaceutical industry, PAM can be used as flocculant, separation of antibiotics used for the Fu type adhesive tablet and process water clarifying agent; in building materials industry, PAM can be used as coating dispersant, thickening stone sawing coolant and ceramic bonding agent; in agriculture, PAM superabsorbent materials can be used as a humectant and soil seed culture agent. In the construction industry, PAM can enhance the hardness of gypsum cement, asbestos cement to accelerate the dehydration rate. In addition, PAM can also be used as protection of natural or synthetic leather coatings and additives such as inorganic fertilizer granulation. The number of coal washing pool adding anionic polyacrylamide is a very important topic. If the amount is too large, resulting in waste, if the amount is not enough, it is difficult to have an effect, so it is reasonable to use the correct amount of 1/1000 to 2/1000 the proportion of 1, 2 pounds of amide, can use 1000 pounds of water. According to this index, under normal circumstances, can be in a certain period of time, the success of the separation of coal and water, surface water after separation will be put out, and then leave the pool at the bottom of the slime, after drying and drying, can be normal use of coal.