As an excellent high-temperature engineering material, Si3N4 ceramic block has the most advantage in its application in high temperature fields. The future development direction of Si3N4 is: (1) to fully utilize and utilize the excellent characteristics of Si3N4 itself; (2) to develop some new flux during the sintering of Si3N4 powder, to study and control the optimal composition of existing flux; (3) to improve milling , molding and sintering process; (4) development of Si3N4 and SiC and Other Materials, in order to obtain more high-performance composite materials. Silicon Nitride Ceramic Block,Silicon Nitride Plate,Customized Silicon Nitride Ceramic Plate,Refractory Ceramic Block SHENZHEN HARD PRECISION CERAMIC CO.,LTD , https://www.hardcm.com
The development of energy-saving and environmental protection industries conforms to the people’s new hope for a better life. It will not only help solve the resource and environmental constraints and release the potential for consumption, but also will stimulate effective investment and drive the growth of emerging industries. This is beneficial to the current, long-term, and multiple benefits. This important move means that for the first time, the country has placed the environmental protection industry in its economic and social development position. It has provided support for the environmental protection cause in the past and promoted the growth of the current economic growth.
As China's environmental pressure continues to escalate, environmental protection issues become more and more intractable. Xi'an Taiyuan Environmental Protection Technology Co., Ltd. combines engineering experience with an understanding of environmental protection water treatment.
At present, China's environmental management is being transformed into a direction for the improvement of environmental quality. The government is not only the promoter of the environmental protection industry, but also the demand side of the environmental protection industry. It needs to make more demands on the environmental protection industry from the perspective of improving the environmental quality. From the purchase of environmental protection projects and environmental protection equipment to the purchase of environmental services.
With the needs of society and the market, the supply of water treatment equipment will also increase dramatically. Facing new opportunities in the water treatment equipment market, the water treatment plant will not only satisfy the market, but also increase the research and development of the latest water treatment equipment. For the community to provide the best quality sewage treatment solutions.
1. Traditionally, wastewater treatment methods have been divided into physical methods, chemical methods, and biological methods. The physical method removes insoluble suspended matter in water. The chemical method is to add chemical substances to the wastewater, and the purpose of purifying the wastewater is achieved through chemical reaction. Biological method refers to taking a certain artificial measures to create the environment for the growth and reproduction of microorganisms, so that the microorganisms multiply, thereby increasing the microbial oxidation and decomposition of organic pollutants. The biological method is mainly used to remove dissolved and colloidal organic substances in wastewater. Compared with physical and chemical methods, biological treatment has many advantages in removing organic carbon, sulfur, nitrogen, phosphorus and other pollutants in wastewater.
1.1 Traditional Activated Sludge Process The Activated Sludge process has been invented by Arden and Lockett since 1914. It has been developed and practiced for 90 years, and it has continuously been innovated and improved in terms of oxygen supply mode, operating conditions, reactor forms, etc. [ 2]. In general, the main advantage of the activated sludge process is that it gives good effluent quality at relatively reasonable cost because the cellular material is removed from the wastewater prior to discharge; the main drawback is poor controllability. To achieve the desired water quality, complex operations are often required to improve the ability of microorganisms to adapt to environmental and water quality changes.
1.2 biofilm biofilm method and activated sludge method, are the use of microorganisms to remove organic matter in wastewater. However, in the activated sludge method, the microorganisms are in a state of suspension growth, so the activated sludge treatment system is also called a suspension growth system. The microorganisms in the biofilm method are attached to the surface of certain substances, so the biofilm processing system is also called the attachment growth system. The biofilm method mainly includes biological filter, biological turntable, biological fluidized bed method and so on.
The attention of researchers and engineers has emerged with a large number of new single or hybrid bio-reactors [3], such as Membrane Biofilm Reactors, biofilm bio-reactors. Air-lift Biofilm Reactor, Moving Bed Biofilm Reactor, Hybrid Activated Sludge-Biofilm Reactor, Sequencing Biofilm Reactor (Sequencing) Batch Biofilm Reactor), upflow anaerobic sludge blanket-anaerobic biological filter (UASB-AF) and attached growth stable pond (Attached-growth Ponds), etc. At present, the main technical problems that need to be studied in the biofilm method are: development and breakthrough in theoretical research; optimization of process design; application of lightweight, high-strength, inexpensive, long-life filter media; Membrane denitrification research.
1.3 Biological Contact Oxidation Bio-contact oxidation is a biofilm process between the activated sludge process and biological filter. The contact oxidation tank is filled with fillers. Some of the microorganisms attach to the surface of the filler in the form of biofilms, and some of them are floccularly suspended in water. Therefore, it has both the characteristics of activated sludge and biological filter. Since the filter material and its biofilm are submerged in water, it is also called a submerged biological filter. There are many forms of biological contact oxidation equipment, which can be divided into diverter type and direct current type depending on the flow state. From the oxygen supply methods, it can be divided into aeration type, mechanical aeration type, sprinkler type and jet aeration type. Most of the fillers in the bio-contact oxidation cell are honeycomb. At present, the better application is a comprehensive aeration of the mesh composite filler. The fibrous filler has a good application prospect. In general, the biological contact oxidation method is characterized by: a high volume load; there is no problem of sludge expansion, operation and management is simple; there is a strong adaptability to changes in the quality of water.
In general, traditional wastewater biological treatment methods have relatively mature experience in terms of design theory and practical operation management. However, with the development of petrochemicals and organic chemicals, the types and quantities of organic materials are increasing, and the quality of municipal wastewater to be treated is becoming more and more complex. It is necessary to research and develop new wastewater treatment biotechnology. In addition, with the increasing shortage of water resources and people’s increasing awareness of environmental protection, further efforts to remove highly biodegradable substances and nitrogen and phosphorus nutrients are also required to research and develop new wastewater treatment biotechnology.
2. New Sewage Treatment Technologies Introduced in Recent Years In recent years, the main development directions of urban sewage treatment technologies have been [1]: The traditional activated sludge process and technology have been reformed to make it more economical and reasonable; research and development can replace activity. Sludge treatment process and technology; research and development targets for the treatment process and technology of urban wastewater reuse, which led to the development of a number of new wastewater treatment processes, such as adsorption biodegradation (AB) process, batch batch reactor ( SBR), membrane separation activated sludge process, oxidation ditch process, etc. [1-3].
2.1 AB method The AB method is an abbreviation for Adsorption Bio-degradation. It is the University of Aachen, Federal Republic of Germany. A new process developed by Prof. Bohnke in the mid-1970s based on the traditional two-stage activated sludge process (z-A method) and high-loaded activated sludge process, is an ultra-high-loaded activated sludge process, technically There is a breakthrough [3]. Suitable for medium and small cities with low economic level. The main disadvantage of this process is the high sludge yield.
2.2 SBR method.
The SBR method is an abbreviation of batch type activated sludge method. In recent years, due to the development of the electronics industry, the whole system of the sewage treatment plant has achieved self-controlled operation, and it has technically created conditions for the intermittent operation of the activated sludge process. The main deformation processes are intermittent cyclic activated sludge process (ICEAS) and circulating activated sludge process (CA-ST). It is suitable for sewage treatment in tourist cities where the quality of effluent water quality is relatively high and the water quality and quality fluctuate greatly.
2.3 MSBR (Modified Sequencing Batch Reactor) MSBR modified batch reactor, Shenzhen Yantian treatment plant in China for the first time using this process [6].
The MSBR process is currently considered to be the latest and most intensive wastewater treatment process. From the aspects of system availability, civil engineering capacity, total installed capacity, energy saving, reduced operating costs, and land saving, it has obvious advantages.
2.4 CASS
CASS (Cyclic Activated Sludge System) is also an improved sequential batch reactor. It is an internationally recognized advanced treatment process for domestic sewage and industrial wastewater. The main principle is to divide the reaction pool of the sequencing batch activated sludge process SBR into two parts along the length direction. The front part is the biological selection area also called the pre-reaction area, and the rear part is the main reaction area, in the main reaction area. The rear part is equipped with a lifting device which can be raised and lowered. The aeration, sedimentation, etc. are circulated in the same tank cycle, eliminating the secondary sedimentation tank and sludge return system of the conventional activated sludge process.
2.5 Unitank
Unitank was developed by SEGERS in Belgium in the 90s of the 20th century. From the operating point of view, it is like a deformation and development of the SBR method, with the advantages of the SBR method and the traditional activated sludge method. The integrated design not only has the main features of the SBR method, but also can be like the traditional activated sludge method. Continuous operation at constant water level.
2.6 Oxidation Ditch
Oxidation ditch, also known as oxidation ditch, is named after its structure is a closed ditch. Oxidation ditch process belongs to suspension biological treatment technology and is similar in mechanism to delayed aeration process. Common oxidation ditches include Carrousel oxidation ditch, alternating work ditch oxidation ditch, Orbal ditch ditch, and integrated oxidation ditch. Compared with conventional activated sludge process or traditional activated sludge process, it has the following advantages [1, 3, 12]: simple process flow, fewer structures, convenient operation and management, stable treatment effect, good effluent quality, and infrastructure cost Low, low operating costs, low sludge generation, stable sludge properties, ability to withstand water volume, water quality impact load, high dilution capacity for high concentration industrial wastewater, long sludge retention time, easy nitrification reaction By adjusting the amount of oxygen supplied, higher denitrification efficiency can be obtained. The oxidation ditch process is one of the wastewater treatment technologies currently used in China.
2.7 A 2 / O method A 2 / O (anaerobic, anoxic, aerobic) method is commonly used nitrogen and phosphorus removal process. Sewage treatment plants in many cities in China, such as Guangzhou Datansha Sewage Treatment Plant and Guilin's No. 4 Sewage Treatment Plant adopt this process.
3, technology status and development trend 3.1 First-level treatment:
From the perspective of the traditional urban sewage treatment process, the first-level treatment part has not seen much breakthrough in the technological theory in recent years, and the process flow is roughly as old. The major developments in the near future have been the improvement of the mechanization and automation of processing equipment and the development and development of various mechanical processing equipment. For example, various types of grids, grids, bell-type grit chambers, Dole grit chambers and various types of desiltering devices and cleaning devices have appeared.
3.2 Secondary treatment:
From the perspective of secondary processing. Still based on biochemical methods, the typical process pattern is still sewage through the grid, to the grit chamber (or aeration grit chamber). To the initial sedimentation tank, aeration tank, secondary sedimentation tank, and then discharged. In the biochemical process, in order to remove nitrogen and phosphorus. In recent years, sewage treatment plants in many countries have used A/O and A2/O methods to treat sewage. In some countries, land issues have become increasingly tense. Physico-chemical methods are being considered to replace biochemical methods to achieve better treatment of phosphorus, nitrogen, heavy metals, color, etc. At the same time, the processing plant occupies a small area and saves energy. Easy to automate management.
3. 3 The use of new processes, new technologies, new equipment, etc. to improve the treatment effect because of lime water treatment technology is a very comprehensive technology. It involves a wide range of science and technology. With the development of research and production in various countries in the world, traditional crafts have been continuously improved or updated. In recent years, new processes (processes), new technologies, and new equipment used for urban sewage treatment are roughly as follows:
â—‹1 In terms of separation technology, rotary solid-liquid separation devices, new gravity sedimentation technology and high-efficiency air-floatation technology are mainly used.
(1) Solid-liquid separation technology. The main performance of the use of advanced rotary mechanical grille. This kind of mechanical grid has special power with good hydraulic conditions, large flow of water, high efficiency, and low head loss.
(2) Adopt mud-type large wave plate inclined plate sedimentation tank. "Precipitation efficiency can be increased by about 1 times", "volume load can be increased by l times." “The structure is compact and reasonable. The capacity utilization coefficient can reach as high as 91%; the new high-efficiency precipitation device with strong adaptability to the original water load changes can be used in the secondary sedimentation tank and the tertiary treatment coagulation sedimentation tank [6].
(3) High-efficiency air flotation technology The so-called high-efficiency air flotation technology uses high-efficiency dissolved gas tanks and other devices to reduce the dissolved gas pressure and reduce energy consumption compared with ordinary pressure dissolved air flotation. 8 to 12 times, reducing the pool capacity 80%. Investment and floor space can be reduced, and operational control is stable [6].
â—‹2 In activated sludge and biofilm process technology. The main research or use of micropore aeration, A / O and A2 / 0 process, oxygen aeration, oxidation ditch, oxidation pond, jet aeration, A-B method, TF / SC process, sBR (sequencing batch activated sludge method ) System etc.
4. At present, the main problems found in integrated wastewater treatment equipment are:
A. The environmental protection mechanism is not yet sound
B. The construction of environmental protection infrastructure is seriously lagging behind
C. The situation of water environmental protection is not optimistic
D. Non-point source pollution has not yet attracted attention
E. Some enterprises are polluted illegally and illegally, and environmental pollution and environmental risks are prominent in some areas.
F. The ability to monitor environmental law enforcement needs to be strengthened.
Therefore, environmental protection water treatment is the mutual result of the trinity of the government, industry, and executive companies. Government supervision, industry regulations, and sources of pollution control funds can surely solve the continuous improvement of quality.
Taiyuan is one of the service providers of environmental protection water treatment equipment. We have the responsibility to provide services for the free diagnosis of sewage treatment as follows.
A, to provide free environmental protection water treatment equipment incurable diseases diagnosis
B. Optimization and upgrading of water treatment equipment and technological transformation of water treatment equipment
C, free compliance diagnosis, diagnostic compliance, non-compliance double compensation!
D. Environmental-free water treatment equipment free of charge for lifetime diagnosis, non-compliance double compensation
Taiyuan provides continuous service, our service type
A, remote diagnosis
B, home diagnosis
C, company diagnosis.
In short, Taiyuan provides our customers with:
1. Pre-sale consultation, original equipment diagnosis optimization upgrade proposal
2. Equipment floor plan
3 system control electrical circuit diagram
4. Process flow chart
5. Process Control Node Diagram
6. Equipment maintenance registration card
7. Equipment operation registration card
8. Safe Operation Regulations (to assist the owner in preparation)
9. Operational flowchart (assisted by the owner)
10. Certificate of conformity, equipment marking, etc.
11. System host operating instructions
12. Detailed list of system equipment
13. Conduct skills training for personnel
Xi'an Taiyuan Environmental Protection Technology Co., Ltd. Service concept; ask questions, ask questions and answer questions.
How to choose the hospital sewage treatment? Is the integrated wastewater treatment standard?