Led by Zhang Liqun Research Group of Advanced Elastomer Research Center of Beijing University of Chemical Technology, the multi-disciplinary experts such as the leading enterprises in the joint industry, tissue materials and machinery, completed the research and development of the "multi-stage screw desulfurization technology of granular regenerated rubber" "The results were selected" national key energy-saving low-carbon technology promotion directory "(2017 low-carbon part).
the results take the recycling of waste rubber as the research object. In view of the problems of traditional high temperature and high pressure dynamic desulfurization, large pollution reduction, high energy consumption, low safety and labor intensity,independently designed and manufactured complete sets of equipment of multi-stage screw continuous desulfurization , developed a high-efficiency green continuous desulfurization process and formula, prepared granular renewable rubber,the invention realized the environmental protection, energy saving, safety, continuous and high efficiency of the complete set of technological process of preparing recycled rubber with waste tire rubber as the main raw material,This is of great significance to China's waste rubber processing industry, cleaner production, energy saving and air pollution control .
Introduction of results and technology
Ò»¡¢Technology item: preparation of granular regenerated rubber by continuous desulphurization by multi-step screw
¶þ¡¢technical categories: carbon reduction technology
Èý¡¢the field and scope of application: chemical industry , the field of waste disposal and comprehensive utilization
ËÄ¡¢the status of the application of technology and industrialization
China is the largest waste rubber producer in the world. In 2014, the output of used tires was 320 million pieces and the weight was over 10 million tons. Traditionally , the main treatment of China's waste rubber is incineration or preparation of recycled rubber with low resource utilization and serious pollution.China attaches great importance to the green sustainable development of waste tire recycling industry, in recent years it has issued a number of industrial policies to support, guide and standardize the development of tire recycling industry.Particle regenerated rubber prepared by this technology can be used instead of synthetic rubber, and it can replace 0.5 ton of synthetic rubber for every ton of granular regenerated rubber produced.At present, Jiangsu, Beijing and Hebei have established respectively 10,000 tons of recycled rubber production lines with the technology,compared with the desulphurization technology such as tandem cooling, single / double helix, single screw, etc., it achieved the closed and continuous process of preparing the whole process from the crumb rubber to the regenerated rubber,completely eliminated the traditional open-type refiner, solved the problem caused by open refiner unorganized gas emissions, the production process was of environmental protection, energy saving, safe, efficient with obvious emission reduction effect , and great potential for development.
According to the different technical principles of the desulfurization process and the refining process in the process of preparing the reclaimed rubber from the waste rubber powder, the technology selects the screw extruder with different functions as the desulfurization equipment and the refining equipment respectively.in the desulfurization process, the waste rubber powder with the regenerated agent destroys the crosslinked network of the rubbers selectively under the shearing action of high-temperature in the desulfurization twin-screw extruder to prepare the desulfurized rubber powder with excellent mechanical properties;in the refining process, the desulfurized rubber powder further interrupts the cross-linking bond under the action of low temperature and high shear in the screw refining extruder to improve the processing performance and obtain the final product.The prepared particle recycled rubber can be used as an alternative to synthetic rubber to reduce the oil consumption of the production of rubber while avoiding the carbon dioxide emissions from incineration of traditional waste tires.
(1)Manufacturing technology of screw extruder for waste rubber desulphurization
By the method of combining theoretical calculation, finite element simulation and experimental simulation, with the analysis of rubber powder friction transmission and complex heat transfer,this technology determined the selection criteria and special manufacturing requirements of desulfurization screw extruder and refining extruder , and creatively achieved the applications of screw extruder in the field of waste rubber recycling .
(2)Double screw continuous dynamic desulfurization and screw continuous refining linkage technology
Based on the desulfurization equipment of screw extruder, a series of desulphurization and desalination process conditions are optimized and designed,which make the recycled rubber preparation process energy saving, environmental friendly, continuous, efficient and so on, and the product performance is excellent and stable.
(3)efficient environmental desulfurization formula technology
The mechanism of desulfurization reaction is analyzed chemically, and the compatibility and interaction of regenerator with rubber are combined.A high performance environment-friendly regenerative auxiliary was developed, and the reasonable amount of the regeneration additive was determined, which replaced the coal tar and aromatics oil polluted by the traditional technology.
The technical equipment consists of raw material weighing automatic weighing device, twin-screw continuous desulfurization extrusion device, multi-screw continuous extrusion refining device, continuous conveying cooling device, automatic packaging device, exhaust gas treatment device, automatic control system,The specific process flow is shown in Figure 1
The technical equipment for the continuous desulphurization of multi - order screw for the preparation of granular regenerated rubber is shown in Figure 2.
Áù¡¢The main technical indicators
1. energy consumption: product energy consumption is about 700kWh per ton, compared with the traditional high temperature and high pressure dynamic desulfurization method, which is reduced more than 20%;
2£®exhaust gas: the emission is reduced by more than 95% compared with the traditional high temperature and high pressure dynamic desulphurization method, which is in line with the requirements of the "ambient air discharge standard" (GB3095-2012) and the "comprehensive emission standard for air pollutants" (GB16297-1996).
3.tire reclaimed rubber properties: water (80 c) = 1%, ash 6%, acetone extract of less than 17.8%, the Mooney viscosity of ML[(1+4) 100] C = 85, the tensile strength is more than 14.0MPa, elongation is greater than or equal to 420%.
The technology has obtained 13 national invention patents and passed the appraisal of scientific and technological achievements organized by China Federation of Logistics and Purchasing in December 2014. In June 2016, it passed the appraisal of scientific and technological achievements organized by China Circular Economy Association.
°Ë¡¢Typical users and investment returns
Typical users: Beijing Luton Yongtai Environmental Protection Technology Co., Ltd., Hebei Maoxiang Rubber Products Co., Ltd., Beijing Xingyu (Tangshan) Rubber & Plastic Environmental Protection Technology Co., Ltd., Jiangsu Qiangwei Rubber Technology Co., Ltd. and so on.
typical case 1
Case Name: Multi-step screw continuous desulfurization green preparation Granule renewable rubber 10,000-ton production line of Hebei Maoxiang Rubber Products Co., Ltd.
construction conditions: making use of the unused land of the company to build a new plant and its supporting infrastructure.
The main contents are as follows: the new plant 2000m2, using 2 sets of multi-stage screw continuous desulfurization, green preparation of particle reclaimed rubber equipment, replacing the original HTS and 3 HV dynamic desulfurization tanks and 24 sets of refining machine .The main equipment is a complete set of technical equipment for the continuous desulphurization of multi - order screw for the preparation of granular regenerated rubber. The total investment of the project is 23 million yuan, and the construction period is 4 months.annual emission reduction is about 40,000 tCO2, carbon emission reduction costs is 10 to 30 yuan / tCO2. Annual economic benefit is 48 million yuan, investment recovery period is about 1.6 years.
typical case 2
case name: Multi-step screw continuous desulfurization green preparation Granule renewable rubber 10,000-ton production line of Beijing Lude Yongtai environmental science and Technology Co., Ltd.
construction scale: Annual output of 10,000 tons of recycled rubber.
construction conditions: construction based on the use of the original plant .
the main equipment is a complete set of technical equipment for the continuous desulphurization of multi - order screw for the preparation of granular regenerated rubber. The total investment of the project is 16 million yuan, and the construction period is 3 months.the main equipment is a complete set of technical equipment for the continuous desulphurization of multi - order screw for the preparation of granular regenerated rubber. The total investment of the project is 16 million yuan, and the construction period is 3 months.annual emission reduction is about 40,000 tCO2, carbon emission reduction costs is 10 to 30 yuan / tCO2. Annual economic benefit is 48 million yuan, investment recovery period is about 1.6 years.
¾Å¡¢Promotion prospects and emission reduction potential.
In the next 5 years, the proportion of technology promotion will be up to 10%, particle renewable rubber production capacity will reach 500,000 t, with a total investment of about 1.05 billion yuan. The annual carbon emission reduction capability that can be formed is about 2.13 million tCO2.