Waste pyrolysis technology

Be more specific – what is it mainly used for?

LZ needs technology related to waste incineration; I’ll show you a few review articles, which should be helpful. Current Status and Prospects of Waste Incineration Technology in China Abstract: The waste incineration industry in China is entering a period of rapid development. Given the limited experience available in this field domestically, it is essential to conduct thorough research and apply waste incineration technologies. Keywords: waste incineration, pollution, environmental protection. With economic development, an increasing population, and rising living standards, the amount of urban waste generated is also on the rise. In today’s world, large amounts of waste have become a persistent source of pollution in cities. Improper disposal of waste can lead to severe air pollution, water pollution, and soil contamination, as well as the occupation of large amounts of land. The pollution caused by waste to the environment has become an increasingly serious problem. How to handle waste economically and efficiently. Waste incineration is one of the effective methods for treating solid waste at present. In developed countries in the West, the use of waste incineration technology dates back nearly 130 years, and it is still considered one of the most effective and economical waste treatment methods today. At present, China mainly relies on open-air stacking and landfilling for waste disposal, and it started relatively late in the research, development, and application of waste incineration technology. In contrast, the level and scale of design, production, and application of waste incineration equipment in our country still fall far short of those in developed countries. Therefore, for our country, it is extremely urgent and important to understand the development trends in combustion technology and equipment for waste incinerators, and to learn and master advanced design and manufacturing techniques for such incinerators. Waste incineration is currently the most widely used waste treatment method abroad, and its greatest advantage is the high degree of resource utilization and waste reduction achieved through this process. Waste incineration plants are located around cities, making it easy to transport waste there; they can also supply electricity or heat to the cities, resulting in good economic benefits. Waste incineration for power generation has become the main method for dealing with waste in developed countries, as well as an important part of the power industry. Computer control is used to operate the incinerator under optimal conditions, and advanced exhaust gas treatment equipment along with strict emission monitoring systems ensure that secondary pollution caused by waste incineration to the atmosphere is minimized. 1 The current situation of waste incineration in China: China is a developing country with rapid economic growth, accelerating urbanization, and an increasing standard of living for its residents, all of which have led to a continuous rise in the amount of urban waste. China currently has over 600 cities, and the amount of urban waste is increasing at a rate of 7–8% per year. Less than 1/3 of the waste is processed, and the proportion that undergoes proper harmless treatment or is used as energy is even lower. With the rapid economic development and the increase in urbanization, it has become difficult to find suitable sites for landfills in areas surrounding cities; as a result, the problem of urban waste management in China is quite severe. At present, 90% of waste in my city is disposed of through landfilling. However, the high-concentration leachate generated by this process, if not properly managed, can cause severe pollution of groundwater and surface water, posing a serious threat to water resources. It also produces large amounts of harmful gases that pollute the atmosphere; if not handled properly, the damage it causes can persist for hundreds or even thousands of years. Waste incineration is a relatively effective method for rendering waste harmless, reducing its volume, and recovering resources from it. Although our country has made considerable progress in waste incineration, it is still in the stage of exploration and research. In the 1990s, attention began to be paid to the use of waste incineration technology in major cities and coastal areas. However, due to the slow pace of introducing incineration technologies and flue gas treatment technologies, as well as difficulties in controlling investment costs, no substantial progress was made. In some areas, due to the difficulty in finding suitable landfills and financial constraints, emphasis is placed solely on burning waste, without proper consideration given to how to burn it effectively and thoroughly, or to how to ensure environmental protection and efficient use of energy. Nevertheless, thanks to continuous research in recent years, significant progress has been made in waste incineration technology. 2 Problems Faced in Waste Incineration Treatment Waste sorting and collection is an important step in achieving comprehensive waste management. By collecting materials in a categorized manner and applying different treatment methods accordingly, it is possible to ensure the recycling of useful resources while also **reducing the costs associated with the final disposal of waste. At present, waste sorting and collection have not been widely implemented in cities across our country; some are still in the pilot phase, which is not compatible with the waste treatment methods we are about to adopt. After waste is sorted and collected, both the amount of waste that needs to be disposed of and its composition change. Thanks to sorting, useful resources can be recycled, which reduces the amount of waste that must be disposed of, and at the same time lowers the costs associated with waste transportation and disposal. Waste sorting can also reduce mechanical wear and corrosion, extend the lifespan of incinerators, and lower maintenance costs. It also reduces the content of harmful components, facilitating the control of secondary pollution. Waste sorting is an inevitable trend. Therefore, cities that adopt waste incineration should give full consideration to waste sorting. 3 Analysis of waste properties The properties of waste refer to its physical composition, chemical elements, bulk density, moisture content, ash content, and calorific value. Analyzing the properties of waste is very important, as it serves as the basis for the design of incinerators, the design of engineering systems, and their operation. The nature of waste is directly related to the lifestyle and standard of living in residential areas. Although many cities in the country are planning to build waste incineration facilities, few take into account the characteristics of the waste. 4 Environmental protection measures The main purpose of waste incineration is to conserve land resources, protect the environment, and achieve sustainable development. Waste-to-energy conversion enables the harmless treatment, volume reduction, and resource utilization of waste. However, due to the characteristics of waste, it is inevitable that some substances harmful to the environment are generated throughout the waste incineration process; therefore, appropriate environmental protection measures must be taken to achieve the true purpose of waste incineration. The main pollutants generated in waste incineration include: odors, harmful substances in the flue gases, waste leachate, fly ash, and reactants. Emission standards for smoke gases have now been established and implemented. For the treatment of landfill leachate, spraying it into incinerators is commonly used in China, but wastewater treatment methods are preferred. The odors generated during waste disposal should also be treated and discharged in accordance with relevant standards. 5 Trends and Prospects in the Development of Incineration Technology: Trends in the development of incineration technology: (1) Efforts to purify exhaust gases from waste incineration plants, particularly to remove pollutants such as dioxins, are receiving increasing attention. ⑵The technology for comprehensive utilization of waste incineration waste heat will be further improved. ⑶To meet increasingly stringent environmental regulations, incineration technology is evolving toward the integration of equipment for flue gas purification, residue and wastewater treatment, as well as waste heat recovery. Prospects for the development of incineration technology: The environmental goals for the \"Ninth Five-Year Plan\" include \"bringing about a significant reversal in the deterioration of the ecological environment by 2010, achieving noticeable improvements in the environmental quality in both urban and rural areas, and creating a number of cities and regions characterized by rapid economic development, clean and pleasant environments, and a healthy ecological cycle.\" Waste management is an important part of China’s path to sustainable development, and major cities across the country as well as those in coastal areas with developed economies are actively adopting waste incineration as a treatment method. During China’s 10th Five-Year Plan period, **the strategy of sustainable economic development will be fully implemented, with greater emphasis placed on the coordinated development of the economy, the environment, and resources, as well as increased efforts in environmental protection and pollution control. To strengthen the control of urban waste pollution, efforts are made to introduce, adapt, and absorb advanced foreign technologies and scientific management practices, thereby improving the level of management in addressing urban domestic pollution. Efforts are also aimed at shifting the approach from treating pollution at its end stage to managing it throughout the entire process, starting from the source. Our country has formulated a series of environmental protection regulations, standards, norms, and accompanying technical policies ； However, **preferential industrial policies are still needed to strongly support our country’s emerging waste treatment industry.** The waste management industry should actively explore various financing channels to address the issue of funding shortages ； By employing modern, advanced, and diversified business methods and strategies, it enhances its own viability and profitability; while generating social and environmental benefits, it also creates substantial economic benefits, shortens the investment payback period, and improves the return on investment. To steer the waste management industry in a healthy and sustainable direction.

Another article is about waste incineration abroad. Development of waste incineration technology abroad. The waste incineration method was proposed by Americans as early as 1901. Initially, the main goal was to reduce the volume of waste, but widespread use was not possible due to the inability to control the dust generated by burning waste at that time. By the 1960s, with advances in flue gas treatment technology, this method of incinerating waste became widespread and developed in Europe. 　　Japan’s first waste-to-energy plant was built in Osaka in 1965. Currently, there are around 3,000 waste incinerators and 131 waste-to-energy plants, with a total installed capacity of 650 MW. By 2000, the waste-to-energy capacity reached 2000 MW. There are 8 waste-to-energy plants with a daily waste processing capacity of over 1,000 tons per day (with a maximum of 1,800 tons per day); the largest of these plants was built in 1995, with an electricity generation capacity of 24 MW. Early waste-to-energy plants in Japan used low operating parameters to prevent corrosion of the furnace tubes, resulting in a low power generation efficiency of only 10%–15%; efforts are now being made to raise this to 30%. 　　Waste incineration plants in the United States developed rapidly; by 1990, 400 such plants had been built, with an incineration rate of 18%, which rose to 40% by the year 2000. Waste-to-energy generation in the United States has reached 2000 MW; currently under construction are waste power plants capable of processing 2000 tons of waste per day, with steam temperatures of 430–450 °C and an electricity generation capacity of 85 MW. 　　The largest waste-to-energy plant in the UK is located in London; it has 5 rotary grate boilers and can process 400,000 tons of waste per year. 　　France currently has over 300 waste incineration boilers, capable of handling 40% of the city’s waste. In Paris, there are 4 Martin-type boilers that can process 450 tons of waste per day. 　　Germany possesses the most efficient waste-to-energy technology in the world; by 1998, it had 75 waste incineration boilers. 　　Singapore achieves a 100% waste incineration rate, with a waste-to-energy plant with a capacity of 2,700 tons per day being built in 1986. 　　At present, due to the serious environmental problems posed by incineration technology, Japan **has decided to shut down all of the more than 2,000 incineration plants across the country gradually. Many in the United States and Europe **are no longer building new incineration plants. 　　Countries consider that incineration technology has the following main problems: 1. Incineration cannot handle all types of waste; sorting is necessary first. Waste that cannot be burned (such as old tires, plastics, and hazardous waste) requires alternative methods of disposal. And the pollution problems associated with the reuse of these wastes have not yet been properly resolved. 　　2. Burning produces dioxins. After years of research, the U.S. Environmental Protection Agency issued a report (Exposure and Human Health Reassessment of 2, 3, 7, 8-Tetrachlorodebenzo-p-dioxin (TCDD) and Related Compounds, US EPA, June 2000). The conclusion of the report is that dioxins are carcinogenic. This conclusion, along with other authoritative reports, has drawn the attention of governments and the public around the world; many governments and regional authorities have raised the issue of banning waste burning among the public. Although the incineration equipment produced in our country is very cheap (only one-third to one-fourth the price of imported equipment), its dioxin emission standard is only 0.5 nanograms per cubic meter. In Europe, North America, and Japan, it is **specified that dioxin emissions must not exceed 0.1 nanograms per cubic meter**. 　　3. Whether domestic or imported equipment is used, the ash and slag resulting from waste incineration, which contain high levels of dioxins and furans, still need to be landfilled. And this technology and cost requirements are extremely high. The United States is already extracting these hazardous wastes, which have been buried 30 meters deep for decades, to carry out pyrolysis and gasification and make use of them.

Research on Pyrolytic Incineration Technology for Medical Waste Xiong Zuhong, Li Haibin, Zhao Zengli, Wu Chuangzhi, Chen Yong (Guangzhou Institute of Energy, Chinese Academy of Sciences) Abstract: This paper proposes a pyrolytic incineration system using a fixed grate furnace. Based on a detailed description of its main components, the operation results are analyzed and discussed. The main components of this incinerator include: a pyrolysis incinerator, a heat pipe heat exchanger, a cooling tower, and a bag filter. The operation results show that during stable operation, the average temperature in the furnace is around 850°C, while the average temperature in the secondary combustion chamber is above 1000°C ； The concentrations of CO, NOx, HCl, and SO2 in the exhaust gas were 71 mg/m3, 125 mg/m3, 27.8 mg/m3, and 21 mg/m3 respectively, all of which are well below the standard limits. Keywords: medical waste, pyrolysis incineration, fixed grate furnace. Medical waste refers to the total waste generated in hospitals, clinics, health and epidemic prevention agencies, health care facilities, testing laboratories, and other entities related to healthcare. These wastes contain a large number of infectious pathogenic microorganisms, bacteria, and viruses, which exhibit characteristics such as spatial transmission, acute transmission, and latent transmission. The harm caused by these viruses and bacteria is dozens or even hundreds of times greater than that of ordinary urban household waste, posing a direct threat to people’s health and public health safety; therefore, it is very important to carry out harmless treatment of these wastes. Currently, incineration is the method most commonly used, both domestically and internationally, for the disposal of medical waste. . Due to its simple methodology, ease of operation, short treatment cycle, high efficiency, and a volume reduction rate of 90% or even higher, incineration is recognized as a relatively ideal treatment method. However, hospitals, outpatient clinics, health centers, and the like in most towns and cities in our country still use traditional incinerators, which are simple combustion devices with a single combustion chamber, without a secondary combustion chamber or an exhaust gas purification system. Since the design of these traditional incineration units is not suited to the large variations in the calorific value and composition of medical waste, the waste is not burned completely, allowing potentially harmful pollutants to re-enter the environment. This not only results in incomplete treatment of hazardous substances but also leads to more severe secondary pollution. The Medical Waste Management Regulations also stipulate that hazardous waste such as medical waste must be treated in a centralized manner. Therefore, it is necessary to develop a set of safe, efficient, energy-saving, and environmentally friendly medical waste incineration technologies based on the physical properties of medical waste, in order to meet the needs for centralized treatment of urban medical waste. To this end, by drawing on Japanese incineration technology and combining it with the proprietary technologies of the Guangzhou Energy Research Institute, a pyrolytic incineration system using a fixed grate furnace was developed and successfully operated at the waste treatment plant in Boluo County, Guangdong Province. This paper introduces the components of this system and analyzes and discusses the operational results. I. Experimental System (1) System composition of the incinerator The thermal pyrolysis incinerator system for medical waste is mainly composed of a pyrolysis incinerator (with the first combustion chamber and the second combustion chamber integrated together), a heat exchanger, a cooling tower, a bag filter, and other auxiliary equipment. As shown in Figure 1, the waste is fed into a first combustion chamber using a grab. In an oxygen-deficient environment, the waste does not burn completely in this chamber; instead, a pyrolysis reaction occurs, producing combustible gases. These gases enter a second combustion chamber where they burn fully at high temperatures. The hot flue gas resulting from this complete combustion is cooled rapidly to 450°C by introducing an appropriate amount of cold air, after which it passes through a heat exchanger made of heat pipes for further cooling. It then enters a spray cooling tower, where its temperature is reduced to 180°C, followed by purification in a bag filter to remove dust. Calcium is added to the flue gas to remove acidity, and activated carbon is used to absorb organic substances and heavy metals. Finally, the gas is expelled into the atmosphere through a fan connected to a chimney. Tables 1 and 2 list the main parameters of the pyrolysis incineration system, as well as the models and power ratings of the main auxiliary equipment. (II) Pyrolysis incinerator: Selection of the structure for pyrolysis incinerators: Based on the combustion method, there are 3 types of structures for pyrolysis incinerators. (1) Grate combustion method, which includes fixed grates and movable grates ； ⑵Bed combustion methods, including fixed-bed, rotary furnace bed, and rotary furnace ； ⑶Fluidized bed combustion method. Considering factors such as economic cost, compact structure, simple operation, and operating costs, a pyrolysis incinerator with the first type of grate combustion method is chosen. This pyrolysis incinerator features a compact design, with the first combustion chamber and the second combustion chamber integrated together. It has a cubic shape and is constructed by welding steel plates; its interior is lined with composite refractory insulation materials. Depending on the operating conditions and requirements, different materials such as silicate bricks, high-alumina bricks, and corundum bricks are used, giving it excellent corrosion and wear resistance. Its temperature tolerance reaches 1300°C, while the lightweight insulation bricks help keep the outer surface of the furnace below 80°C. While improving the operating environment, energy utilization has been enhanced. The structure that combines the first combustion chamber and the second combustion chamber, along with the evenly distributed air inlets around the bottom of the grate, contributes to more stable conditions for pyrolytic combustion. The removable grates in the combustion chamber make maintenance easier and faster. It is easy to start the furnace using a burner for ignition. In accordance with standard requirements, the flue gas generated by material combustion continues to burn in the secondary combustion chamber at temperatures above 850°C; automatically controlled auxiliary burners ensure that the flue gas is burned at sufficient temperatures. The labyrinthine furnace design, along with uniform tangential air supply, creates strong turbulence in the secondary combustion chamber, ensuring sufficient residence time (theoretical design time > 3s), thereby achieving true \"3T\" combustion and effectively removing dioxins. The secondary combustion chamber is equipped with auxiliary burners, viewing ports, and access doors. Thermocouples are installed on the side to control the operation of the burner, while an explosion-proof valve and an emergency air damper are provided at the top to ensure the safety of personnel and equipment in case of an accident. Figure 1: Flow diagram of the thermal pyrolysis incineration process for medical waste
Table 1: Main technical parameters of the thermal pyrolysis incineration system
| Parameter | Value |
|-----------|-------|
| Processing capacity | 3 tons/day |
| Dimensions of the furnace | 2.8m × 1.6m × 2m |
| Cooling water consumption | 100 kg/h |
| Power consumption | 10 kW/h |
| Oil consumption | 0–6 kg |
| Operating temperature | Above 850°C |
| Negative pressure inside the furnace | 100 Pa |

Table 2: Main auxiliary equipment
| Equipment | Model |
|-----------|-------|
| Centrifugal fan | 9-26No.4.5A |
| Centrifugal fan | 9-19No.4 |
| Air compressor | 2m3/min/0.8MPa |
| Bag filter | LDMC1/3/15 |
| Stepper motor | 110BYG |
| Water pump | TP78E |
| Burner | DZR-005-Y |

| Parameter | Value |
|-----------|-------|
| Power | **kW** |
| 1.5kW | 1 |
| 11kW | 2 |
| 0.5kW | 1 |
| 0.2kW | 2 |

(III) Heat pipe exchanger
The high-temperature flue gas generated by waste combustion serves as a heat source; recycling this heat can reduce the operating costs of the entire system, improve economic efficiency, and at the same time lessen the burden on exhaust gas treatment. However, waste incinerators differ from ordinary industrial furnaces; their operating media and conditions are unique, and the utilization of waste heat must be carried out on the premise of ensuring the safety of the incineration system and preventing the formation of dioxins. According to currently established theories, if the flue gases generated from waste incineration are cooled gradually below 550°C, the likelihood of the reformation of harmful gases such as dioxins increases; whereas a rapid cooling process can effectively prevent the reformation of such harmful substances. The inlet temperature of a heat pipe heat exchanger should generally be below 650°C. Therefore, this design takes into account the introduction of appropriate cold air at the outlet of the secondary combustion chamber of the incinerator, in order to rapidly cool the flue gas temperature from 1100°C to 600°C, thereby making use of the waste heat in the temperature range of 600°C to 450°C. Using waste heat to heat the primary and secondary air to above 200°C is beneficial for the pyrolytic combustion of medical waste. (IV) Cooling Tower: To control the formation of dioxins and ensure the proper operation of the bag filter, the flue gas exiting the heat pipe exchanger must be cooled instantly in a cooling tower. Since the cooling water evaporates rapidly upon being sprayed into the cooling tower, the cooling water passing through the cooling tower can effectively cool the flue gas quickly. Therefore, atomization nozzles are installed at the bottom of the cooling tower; these nozzles have a structure for mixing gas and liquid. The tower is equipped with a gas distribution screen; cooling water is sprayed in a mist form from nozzles to come into full contact with the hot flue gas, rapidly cooling the gas from 450°C to 180°C, thereby suppressing the formation of dioxins and polychlorinated dibenzofurans. Prolonged operation has shown that this type of nozzle can effectively atomize water; the water mist is evenly distributed across the cross-section of the tower and evaporates completely within 1 second. The automatic control system, which is set based on the temperature of the exhaust gas at the outlet of the cooling tower, can automatically adjust the speed of the water pump, thereby enabling effective control of the water flow rate without generating wastewater. (V) Bag filters: At the outlet of the cooling tower, a stepper motor drives a spiral device equipped with activated carbon, which is used to add activated carbon to the flue gas. When the consumption reaches 50 mg/Nm3, this setup can effectively absorb heavy metals and residual dioxins from the exhaust gases. Given that the flue gas in this system is characterized by high temperature, chlorine content, and high corrosivity, a high-pressure pulse LDMC series modular high-efficiency dust collector is used. The equipment is equipped with an electric heating device to prevent dew formation on the bag. To prevent the bag filters from being damaged by hot flue gas, a bypass pipeline is installed between the outlet of the spray tower and the inlet of the bag filter. In the event of an emergency, such as an excessively high flue gas temperature, the high-sensitivity thermocouples located in front of the valves promptly transmit the temperature signal to the computer control system. The control system then closes the inlet valve within an extremely short time. At the same time, the outlet valve of the bag filter is closed, while the bypass pipeline valves and the cold air valves are opened, allowing the hot flue gas to be discharged through the bypass route. This ensures the safety of the bag filter. II. Operational Results and Discussion The medical waste used as raw material came from various hospitals in Baiyun District, Guangzhou; its main components were plastics, paper, fabrics, glass, etc. The elemental analysis and calorific value are shown in Table 3. Table 3 Element analysis (wt%) and calorific value of medical waste raw materials: C H O N S Lower calorific value (kJ/kg): 56.82 7.83 29.87 0.35 0.08 8708.8 A burner is used in the pyrolysis incinerator to start the combustion process; in order to allow the gasification furnace to heat up rapidly, the air supply volume should be increased appropriately to ensure thorough and intense combustion of the waste. At the same time, the burner in the secondary combustion chamber is activated; this burns off the unburned carbon particles in the furnace, which is the primary combustion chamber, and simultaneously raises the temperature of the secondary combustion chamber. When the furnace temperature reaches around 700°C, the air supply to the furnace and the secondary combustion chamber is adjusted appropriately so that the waste undergoes pyrolysis within the furnace, and the resulting combustible gases burn fully in the secondary combustion chamber. The air equivalent coefficient for a typical furnace chamber is 0.25, while the air excess coefficient for the secondary combustion chamber is 1.3. Figure 2 shows the changes in the temperature of the furnace and the secondary combustion chamber from startup to stable operation. Due to the high calorific value of medical waste, as shown in Table 3, it reaches 8708.8 kJ/kg. The pyrolytic volatiles account for over 80%, and these volatiles mainly consist of flammable gases such as carbon monoxide, hydrogen, methane, etc. These flammable gases burn completely in the secondary combustion chamber. It releases heat, generating high temperatures that decompose some organic pollutants. As can be seen from Figure 2, the temperatures in the furnace chamber and the secondary combustion chamber gradually increase over time after the furnace is started. Eventually, the temperature in the secondary combustion chamber stabilizes above 1000°C even when the burner is turned off. In comparison, the temperature in the furnace chamber fluctuates more significantly, but it remains above 850°C as well. (1) Change in temperature over time – Figure 2. (2) Change in major pollutants in flue gas over time – Figure 3. Figure 3 shows the results of online monitoring for 6 types of pollutants. During the actual operation of the incinerator, carbon monoxide exhibits the greatest fluctuations, while the fluctuations of other pollutants over time are relatively small. In practical measurements, the variations in carbon monoxide levels are mainly influenced by the operations of the incinerator; factors such as the addition of raw materials and adjustments to the amount of air supplied directly affect the levels of carbon monoxide emissions. Fluctuations in other substances such as sulfur dioxide are mainly influenced by the amount of sulfur-containing elements in the raw materials themselves ； The influence of calcium addition amount and operating conditions. Table 4 shows the comparison between the actual measured values of various pollutants in the exhaust gas and the limit values, all of which meet the \"Pollution Control Standards for Incineration of Hazardous Wastes\". Table 4 Comparison table of actual exhaust gas values and standard limits. Emissions: CO, NOx, SO2, HCl, Cr, Ni, Pb, Hg; Soot density. Actual values in mg/m3: 71, 125, 21, 27.8, 5.7, 10-3, 0.4, 0.27, 4.1, 10-5. Grade: 1. Standard limits in mg/m3: 100, 500, 400, 100, 0.1, 1.0, 1.0, 0.1. Grade: 1. Note: Standard limits are based on the “Standards for Pollution Control during Incineration of Hazardous Waste” GB1848-2001. III. Conclusion: This fixed-grate furnace pyrolysis-incineration system exhibits good operational characteristics, with the various key components—such as the pyrolysis-incinerator, heat pipe exchanger, cooling tower, and bag filter—working well together in terms of parameter coordination. The temperature in the secondary combustion chamber remains stable above 1000°C even when the burner is turned off ； The furnace temperature can also reach over 850°C. The measured concentrations of pollutants in the flue gases from the pyrolysis incineration of medical waste are well below the standard limits. The operational test results of this system show that fixed-grate furnaces exhibit good technical and economic performance in the efficient and clean treatment of medical waste, making them fully suitable for adoption in China’s centralized medical waste treatment market. References: Xu Changzhong, Yuan Changyou. New processes for medical waste treatment – high-temperature pyrolysis. China Environmental Protection Industry, 2004, 2: 84-85, 87. Li Xin, Liu Xiaofeng, Shen Qiang. Technology for incinerating medical waste using rotary grate furnaces. China Environmental Protection Industry, 2004, 2: 78-83. Zhao Chun. Discussion on technologies for incinerating medical waste. Northern Environment, 2001, 3: 45-48. Chen Dexi. Discussion on technologies for centralized incineration of medical waste. China Environmental Protection Industry, 2004, 2: 67-69. Li Donghong, Feng Shou, Qi Guosu, Sun Jun. Research on pyrolytic incineration technologies for urban medical waste. 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