■ Urban sewage
■ Municipal and industrial comprehensive wastewater
■ Industrial wastewater
■ Hazardous wastewater
■ Landfill leachate
■ Contaminated groundwater and contaminated surface water.
The following is pact &；; Typical application and performance of reg system;
Convention on Organic Compound Wastewater &; Reg This system is used for pretreatment and direct discharge of various organic compounds, plastics, synthetic fibers, solvents, dyes and pesticides. A professional chemical plant in Louisiana uses two-stage aerobic PACT &; The sewage treated by reg meets the requirements of organic matter and sewage toxicity discharged into Mississippi River.
Wastewater from pesticide production: The wastewater from a factory contains 19 kinds of pesticides, and the concentration exceeds 3400 ppm. Reg system processing; Reg chemical oxygen demand removal rate is over 99%, and the total amount of pesticides is reduced by 99.8%. Polluted groundwater PAC T&; Reg This system has been applied to the treatment of polluted groundwater with good results. There is an agreement &; Reg batch treatment system, the groundwater polluted by a local mobile household goods and coating manufacturer, has reduced the contents of COD and BO D by more than 99% after being treated by this system. With the increasingly strict management regulations of landfill sites, the problem of landfill leachate is becoming more and more serious. Reg This system is more used to treat the leachate of municipal solid waste and hazardous waste landfill. There is a dangerous municipal landfill near Los Angeles, California. Compared with other processing systems, PACT &: reg; The system has the lowest cost, the least land occupation and the best processing stability. It was installed by 19 88.
Convention on refinery and petrochemical wastewater &; Reg This system is increasingly used for the treatment of refinery wastewater and petrochemical wastewater. There are many refineries and petrochemical plants in the United States and other places, PACT &; Reg The system meets many regulatory requirements, including bioassay, organic matter and chemical oxygen demand (COD), or used for wastewater reuse. Pilot and processing tests
In order to give full play to pact &；; Reg system flexibility, we provide a complete set of pilot and wastewater treatment capacity tests. We can design a specific test plan according to your wastewater treatment needs. Wastewater treatment test equipment includes laboratory scale and pilot scale. The former is carried out in our laboratory in Wisconsin, and the pilot scale is carried out at the user's site. Movable contract &; The pilot test in reg system may or may not include activated carbon regeneration. The experiment can include various biological treatment modes: aerobic process, anaerobic process, single stage or double stage.
Our analytical laboratory can provide strong support for the above experiments. Our laboratory is one of the best equipped laboratories in the United States in analyzing industrial, municipal and harmful sewage, water supply and sludge. In addition, we also have a sample processing, storage and disposal (TS D) facility officially licensed by RCRA, which can process and store various samples. (RCRA: Resource Protection and Restoration Law) We have many years of experience in treating various kinds of wastewater. Siemens Water Treatment Technology Department can work with you to detect your sewage, carry out conceptual design and design a cost-effective treatment scheme to ensure that your wastewater treatment complies with environmental management regulations. Our experience ensures that the treatment plan is designed from the laboratory.
Reliable development from pilot scale to production scale.
At present, PACT & ampreg has been widely used all over the world to help users meet the following requirements:
■ Emission Regulations for Organic Chemicals, Plastics and Synthetic Fibers (OCPSF).
■ RCRA land protection regulations prohibit the use of land for sewage treatment and require the treatment of landfill leachate and polluted groundwater.
■ Strict biological identification standards for discharged water.
■ Regulations on the treatment of industrial wastewater discharged into drinking water sources
■ Strict COD and total nitrogen control standards shall be implemented for all kinds of sewage discharged into natural water bodies.
Pact & reg system can be used for renovation and new construction projects, ranging from factory prefabricated equipment with a daily processing capacity of 2 0~400 cubic meters to on-site installation equipment with a daily processing capacity of 4,000 cubic meters, and large-scale systems with a daily processing capacity of 2 00,000 cubic meters specially designed according to customer requirements. And can be a single-stage system and a two-stage system, a continuous processing system or a batch processing system. The users of PACT & ampreg system can enjoy more than 3 0 years of technical experience, pilot technology and engineering design expertise.
system operation
The powdered activated carbon used in PACT-AMPREG system is directly added to the anaerobic or aerobic biological treatment process, and the physical adsorption and biological metabolism process are carried out simultaneously. Activated carbon can "buffer" the toxicity of toxic organic substances in wastewater, thus reducing its adverse effects on biological systems. Aerobic exercise. Reg In this system, the influent flows into the aeration tank, and carbon powder is added into the aeration tank to form a certain proportion of mixed suspended solids. After aeration reaction, the mixed slurry of treated wastewater and carbon powder enters the secondary sedimentation tank for solid-liquid separation.
Anaerobic pact &；; Reg In this system, before the wastewater enters the anaerobic reactor, it is mixed with the added powdered carbon. Under the synergistic effect of powdered carbon and organisms, a part of powdered carbon and biosolids enter the sludge treatment process. The specific treatment method should be selected according to factors such as sludge volume, treatment cost and carbon consumption. Waste sludge can be dehydrated or pumped into wet air oxidation equipment, where carbon is regenerated and biological sludge is destroyed. Wet air regeneration equipment can be operated by self-heating without external heat source. Activated carbon recovery, biological sludge digestion, sludge basically does not need secondary treatment or disposal.
The main function of PACT system is to transform suspended, colloidal and soluble pollutants into biodegradable powdered activated carbon bio-colloid, promote sludge sedimentation and improve the removal rate of dissolved organic matter, chromaticity, toxic substances and heavy metals. Relevant literature shows that Q 1 not only maintains the advantages of traditional activated sludge process, but also greatly improves the removal rate of organic and inorganic pollutants due to the addition of activated carbon adsorbent. It has a good removal effect on medicine, electroplating, food, surface coating, petrochemical industry, landfill leachate and printing and dyeing wastewater. Wao wet oxidation regeneration system mainly includes high-pressure pump, air compressor, heat exchanger, heating boiler and DSE (differential elution) ash removal system. The process can oxidize and decompose high-concentration organic matter and toxic substances in wastewater or sludge at high temperature and high pressure. The purpose of high temperature is to accelerate the oxidation reaction, and the purpose of high pressure is to maintain the existence of liquid phase. Excess sludge is sent to WAO system through gravity concentration tank to regenerate activated carbon, and the organic matter adsorbed by activated carbon is decomposed at high temperature and high pressure. The regenerated carbon is sent to the storage tank and then flows back to the aeration tank, and part of it is sent to the ash discharge tank for ash discharge. The control emphasis of regeneration process is pressure, temperature, high-pressure air and ash removal. The optimum technological conditions of this system are as follows: temperature 230℃, time 65438 0 h, oxygen supply pressure P=0.6 MPa. The concentration of carbon sludge entering the WAR system is >: 7%, and the suspended solid content shall not be lower than 7%, so as to provide stable sludge content in WAO system. 2. 1 What is WAO process system? In fact, there are many different classification methods of activated sludge process, such as air aeration and pure oxygen aeration. According to the classification of aeration methods, it can be divided into blast aeration and mechanical aeration. During the operation of activated sludge process, the key point is to maintain the activity and cohesiveness (settling performance) of activated sludge. However, the coagulation performance of activated sludge is easily affected by influent quality and external factors, which leads to abnormal phenomena such as sludge floating in the effluent of secondary sedimentation tank. At this time, adding powder filler, coagulant or other chemicals to the aeration tank will often achieve good results, which is the so-called "adding" activated sludge process. Among them, powder filler is the most added, also known as powder activated sludge method. Because the adsorption capacity of powder filler to influent organic matter is much stronger than that of activated sludge, there will be a phenomenon that powder filler continuously adsorbs influent organic matter and activated sludge microorganisms continuously degrade the organic matter adsorbed by powder filler. Therefore, it has the characteristics of impact load resistance, improving the removal ability of refractory organic matter and good decoloration effect. In addition, this method can improve the sedimentation performance of activated sludge and reduce or inhibit sludge bulking. The powder filler used in PACT-WAO system is directly added to the anaerobic or aerobic biological treatment process, and the physical adsorption and biological metabolism processes are carried out simultaneously. Powder filler can "buffer" the toxicity of toxic organic substances in wastewater, thus reducing its adverse effects on biological systems. In the aerobic PACT-WAO system, influent flows into the aeration tank, and powder filler is added into the aeration tank to form a certain proportion of mixed suspended solids. After aeration reaction, the mixed slurry of treated wastewater and powder filler enters the secondary sedimentation tank for solid-liquid separation. In the anaerobic PACT-WAO system, the wastewater is mixed with the added powder filler before entering the anaerobic reactor, and the powder filler and the organism cooperate to produce efficient treatment effect. Like the traditional anaerobic system, the system can recover methane and use it as fuel, thus further improving energy efficiency. After treatment, a part of powder filler and biosolids enter the sludge treatment program. The specific treatment method should be selected according to the amount of sludge, treatment cost and the amount of powder filler. The waste sludge can be dehydrated or pumped to the powder packed oxidation equipment. PACT-WAO system combines many advantages of traditional powder packing-activated sludge method, and combines the process of destroying residual biological sludge and oxidizing pollutants adsorbed in powder packing biological sludge with powder packing-activated sludge method at appropriate temperature and pressure, so as to recycle waste sludge, structurally replace the traditional biological treatment process of activated wastewater, simplify sludge treatment unit, and have no pollutant discharge. PACT-WAO system is to put the substance to be treated in a closed container, and introduce air or high-purity oxygen as oxidant at high temperature and high pressure to degrade the organic matter in sewage according to the principle of wet combustion. In this system, the powder filler is regenerated, the biological sludge is destroyed, and the powder filler regeneration equipment can run by itself without external heat source. The powder filler is recovered, the biological sludge is digested, and the effluent can be directly reused after filtration, which not only realizes the full utilization of water resources, but also realizes the harmless treatment of sludge, and is especially suitable for large-scale urban sewage treatment plants and refractory organic wastewater. Simply put, PACT-WAO process system refers to the organic combination of powder filler biological treatment system and powder filler regeneration system, which integrates the advantages and complementarities of the two systems. At a certain temperature (170 ~ 300℃) and pressure (1.0 ~ 10 MPa), the organics and ammonia nitrogen compounds in various wastewater and sludge can be treated without dilution with oxygen (air). Ammonia and other pollutants are deeply decomposed by catalytic oxidation (contact time is 0. 1~2.0h ~ 2.0h), so that they can be converted into harmless components such as carbon monoxide compounds, nitrogen oxides, water, etc., and at the same time decolorized, deodorized and sterilized, thus achieving the purpose of purifying and treating wastewater. This process does not produce sludge, only a small amount of cleaning waste liquid needs to be treated separately. When it reaches a certain treatment scale, it can also recover energy. According to the need, it can be used as an independent wastewater treatment system, and can also be combined with conventional activated sludge method and anaerobic digestion method to meet the prescribed discharge standards. The treated wastewater can be directly discharged or recycled after filtration. This process solves the problem of excess sludge treatment in sewage treatment plant, completely realizes the harmless treatment of sludge, and can treat all kinds of refractory pollutants. The effluent can be directly reused after filtration. Most importantly, it decomposes toxic and harmful substances into non-toxic and harmless carbon dioxide and water in the process, and only a small amount of inorganic ash is discharged from the whole process system, which completely solves the problem of secondary pollution of sludge. Typical PACT-WAO process system flow 2.2 pact-wao process system flow: powder filler is added into biochemical influent (or in aeration tank) to mix with the returned sludge in aeration tank, and the remaining sludge discharged from sludge concentration tank enters the sludge dewatering device. In the aeration tank, activated sludge adheres to the surface of powder packing. Because of the huge specific surface area and strong adsorption capacity of powder filler, the adsorption capacity of sludge is improved, especially the dissolved oxygen and degradation matrix concentration at the interface between activated sludge and powder filler are greatly improved, thus improving the degradation and removal rate of COD. Generally speaking, in the powder packing system, the dynamic adsorption capacity of COD is 100-350% (weight percentage), that is, one kilogram of powder packing can be removed by adsorption 1.0-3.5 kilograms of COD. Moreover, powder packaging method can deal with toxic and harmful organic pollutants that are difficult to biodegrade. According to the experience, adding powder filler directly into SBR aerobic biochemical pool regularly (every 15-30 days) can obtain good treatment effect. The adsorption mechanism of powder filler and granular filler is actually the same, but adding powder filler into SBR biochemical pool has the following advantages: 1, which saves investment cost, is flexible and convenient to operate, and has high utilization rate of powder filler, and avoids the shortcomings that biofilm growth of filler is blocked, which affects the effluent rate: In PACT-WAO system, activated sludge adheres to the surface of powder filler, and dissolved oxygen at the interface between activated sludge and powder filler is degraded due to its huge specific surface area and strong adsorption capacity. Generally speaking, the removal of COD (depending on the type of wastewater) can be increased by10-40%; 5. Because the toxic and harmful organic matter in the wastewater is adsorbed by the powder filler, the concentration of toxic and harmful substances in the wastewater can be stabilized at a low level, thus ensuring the normal operation of the biochemical treatment system; 6. It has a good effect on preventing the ammonia nitrogen index from rebounding and ensuring that the ammonia nitrogen index of the effluent reaches the standard. 7. Powder packing oxidation is to use oxidant to oxidize organic matter in wastewater into carbon dioxide and water at high temperature and high pressure, so as to achieve the purpose of removing pollutants. Compared with traditional methods, it has the characteristics of wide application range, high treatment efficiency, less secondary pollution, fast oxidation speed, energy recovery and useful materials. The used sludge containing powder filler introduced from PACT-WAO system is concentrated by gravity, pumped through the heat exchanger of PACT-WAO system in the form of powder filler slurry, and then enters the reactor. During this period, compressed air is introduced into the filler slurry. An exothermic reaction takes place in the reactor, which releases heat when the organic matter is oxidized. Organic matter is oxidized, and the surface of powder filler is regenerated. When the filler slurry after oxidation reaction is discharged from the reactor, heat is recovered through a heat exchanger to preheat the feed filler slurry. Subsequently, the regenerated powder filler slurry is returned to the PACT-WAO system. In the whole process, organic matter is digested, and the final products are carbon dioxide, water and a small amount of low molecular weight organic matter (mainly acetic acid). The accumulated ash is discharged from the system and can be easily disposed of. When the solid content of the feed is 6%-7%, the PACT-WAO process is usually a self-sustaining process without additional auxiliary fuel. Its operating advantages are: low operating temperature, energy-saving self-heating operation (heat self-sufficiency), suitability for various treatment scales, complete sealing, no harmful gas emission, low energy consumption, low operating cost, no need for dehydration in advance, no discharge of sulfur oxides, nitrogen oxides and soot particles, no residual sludge, powder filler recovery rate of over 90%, small floor space and stable ash properties. No leaching pollutants ● The effluent can be directly reused after filtration. The schematic diagram of the oxidation treatment unit is briefly described as follows: the wastewater is pumped into the heat exchanger by the high-pressure pump through the storage tank, and exchanges heat with the high-temperature oxidation liquid after the reaction, so that the temperature rises to near the reaction temperature and then enters the reactor. Oxygen required for the reaction is pumped into the reactor by a compressor. In the reactor, the organic matter in wastewater reacts exothermically with oxygen, and the organic matter in wastewater is oxidized into carbon dioxide and water, or intermediate products such as lower organic acids at higher temperature. After the reaction, the gas-liquid mixture is separated by a separator, and the liquid phase is preheated and fed by a heat exchanger to recover heat energy. The high-temperature and high-pressure tail gas firstly generates steam through a reboiler (such as a waste heat boiler) or preheats boiler water through a heat exchanger; the condensed water is separated by a second separator and pumped into the reactor through a circulating pump; and the separated high-pressure tail gas is sent to a turbine to generate mechanical energy or electric energy. Therefore, this typical industrialized system not only treats wastewater, but also uses energy step by step to reduce the loss of effective energy and maintain and supplement the energy required by the oxidation system itself. 1.Application of PACT-WAO process system At present, the application of PACT-WAO system is mainly in the following aspects: 3. 1 Suitable for urban sewage treatment plants of all sizes. PACT-WAO process can be applied to urban sewage treatment on a large scale, which is not only technologically advanced, but also economically acceptable. Cities have broad application prospects and cost advantages for urban sewage resource utilization. The effluent quality of pact-wao process system is good, and it can be directly reused after filtration or ultrafiltration system, which has considerable advantages and meets the extensive needs of urban sewage treatment plants of all sizes. It is embodied in the following aspects: a) PACT-WAO process is affected by influent quality. Small PACT-WAO process is systematically designed according to the characteristics of urban sewage quality. Its rigorous process mechanism and reliable control means can provide safe, hygienic and stable effluent guarantee. B) In PACT-WAO process, powder filler is directly added into anaerobic or aerobic biological treatment process, and the strong specific surface area of powder filler has strong adsorption, which can greatly improve the ability of resisting impact load in combination with the biochemical function of activated sludge, while the quantity and quality of urban sewage are extremely unstable. After adopting PACT-WAO process system, not only the impact load resistance can be improved, but also it can be greatly improved. C) The discharge of activated sludge without excess sludge is an inevitable product of the secondary sewage treatment plant, which generally accounts for 0.5% ~ 1% of the total sewage treatment. However, its treatment cost accounts for 40%-50% of the total operating cost of sewage treatment plants. With the development of modern cities, the discharge of all kinds of wastewater increases rapidly, which makes the sewage treatment of urban sewage plants tend to be medium-sized and large-scale centralized treatment. How to treat a large amount of activated sludge produced by sewage treatment reasonably and effectively is of great practical significance to water treatment workers. Compared with the traditional reclaimed water production process, PACT-WAO process system has no excess sludge discharge, only a small amount of inorganic ash discharge, which completely solves the negative impact of secondary pollution of sludge and reduces most sludge disposal costs. It is of far-reaching significance to improve the environment and enhance the image of sewage treatment plants and surrounding environment; PACT-WAO process has been widely valued and developed in the treatment of high concentration organic wastewater. Considering that the material structure of activated sludge is very similar to that of high concentration organic wastewater, if this technology is successfully applied to the treatment of activated sludge in municipal sewage plants, it will have broad application prospects. Aiming at treating excess sludge by PACT-WAO process system, the design concept of PACT-WAO process system can be considered at the beginning of the design of new sewage treatment plant, which can greatly shorten the process flow and successfully solve the problem of secondary pollution of sludge. For non-new sewage treatment plants, the original system can also be appropriately transformed into PACT-WAO process system. D) The whole PACT-WAO process system has no toxic and harmful gas emission, which plays a positive role in improving the ecological environment of employees and surrounding residents of urban sewage plants and reduces the impact on the environment; E) PACT-WAO system has the advantages of flexible operation, small floor space and low operating cost. From the beginning of the design, the characteristics of urban sewage treatment are fully considered, and centralized optimization is carried out in operation and floor space, and flexible scheduling is carried out in operation, which is convenient for optimizing configuration and expanding project scale according to market demand. Because the PACT-WAO process system adopts autothermal regeneration, it does not need extra energy under normal circumstances, and the fuel is the organic matter in the waste filler mud and the adsorbed organic matter, so it only needs to start the steam, and the energy efficiency is improved by using the heat exchanger. At the same time, the system does not need sludge treatment device and deodorization device, and the running cost is much better than the traditional treatment process. 3.2 When used in petrochemical wastewater, the decomposition rate of hydrocarbon organics and their halides in wastewater reaches or exceeds 99% at the temperature of 204 ~ 3 16℃. Even chlorinated compounds such as PCBs and DDT, which are difficult to be treated by general chemical oxidation, can be reduced by 99% by PACT-WAO process, which greatly improves the biodegradability of the treated effluent and enables the subsequent biochemical treatment to proceed smoothly. Under the conditions of temperature 225 ~ 240℃, pressure 6.5 ~ 7.5 MPa and residence time 1 ~ 1.2 h, the removal rate of organic phosphorus is 93 ~ 95%, the removal rate of organic sulfur is 80 ~ 88%, and the removal rate of COD is 40 ~ 45%, and methanol is not recovered. Using PACT-WAO process to treat phenol-containing wastewater has a good application prospect: the effluent treatment effect is stable, the biodegradability is good, the influent concentration is not too high, and it can be directly discharged after treatment; If the influent concentration is extremely high, biochemical method can be supplemented. 2. Advantages of PACT-WAO process system Compared with other sewage treatment processes and sludge treatment processes, PACT-WAO process system has its unique advantages: 4. 1 No excess sludge discharge l eliminates biological sludge to be disposed of; L No excess sludge is discharged, and biological sludge and pollutants can be removed at the same time; L no secondary pollution of sludge; L Heavy metals in sludge are oxidized to the highest oxidation state and become stable inorganic ash; 4.2 Pollution-free gas emits L organic matter, which is converted into CO2, NOX and H2O；; ; L No dust, nitrogen oxides and sulfur oxides are discharged; Compared with the traditional sewage treatment process, there is no harmful gas emission; Due to the adsorption characteristics of powder filler, the highly volatile mixture remains in the system and is finally biologically treated; L Odor will not escape during aeration, and there is no need to add a deodorizing unit; 4.3 The effluent quality is good. L can treat all kinds of high-concentration organic wastewater and toxic and harmful wastewater. L PACT-WAO system can effectively control the chroma and odor of effluent. L the quality of filtered effluent can directly meet the requirements of reuse water quality. Different from membrane bioreactor, pact-wao system can also effectively remove refractory soluble organic matter; L effectively remove ammonia nitrogen from sewage; 4.4 Simple technological process, convenient management and operation, and low operating cost. L replaces the traditional biological treatment+activated carbon adsorption+sludge treatment+deodorization; L powder filler is regenerated in liquid phase, and solids do not need dehydration; L no pollution gas emission, no need to add deodorization unit; The powder filler used in l PACT-WAO system makes the biological system more stable and more resistant to interference and impact; L will not encounter the problems such as pretreatment (coarse filtration) and ordinary hardening that are usually needed by granular filler filters; The flexibility of the system is high: by selecting the dosage, type and concentration of activated sludge and the adding point of powder, the optimization and flexibility of the process are ensured, so as to treat wastewater with different characteristics in a targeted manner; Flexibility of operation: PACT-WAO system can provide the greatest flexibility of operation, only the amount of powder depends on the change of wastewater quality and the requirements of discharge or reuse; L Sludge can be directly regenerated without dehydration, which reduces the consumption of fresh fillers and operating costs; L There is no treatment cost of excess sludge, and the regeneration of powder filler can greatly reduce the dosage of the system and the cost of sludge disposal; L no deodorization device, reducing investment and operating costs; Compared with granular filler system, the amount of filler in l-PACT-WAO system is much less. The price of powdery filler is lower than that of granular filler; Autothermal regeneration reduces energy consumption: the fuel is the organism and adsorbed organic matter in the waste active filler, so it is only necessary to start the steam and use the heat exchanger to improve energy efficiency.