By Bian Siying, China Huanqiu Contracting & Engineering (Beijing)
Zhang Fuqin, CPPEI
There are over ten types of biodegradable plastics, and this report covers seven: polylactic acid (PLA), polybutylene succinate (PBS), copolymer of butylene adipate and butylene terephthalate (PBAT), polyhydroxybutyrate (PHB), polyvinyl alcohol (PVA), carbon dioxide copolymer (PPC, PEC), and polycaprolactone (PCL).
Capacity
China's biodegradable plastics industry started late, with a robust growth, however. The capacity of biodegradable plastics in China increased from 230 000 t/a in 2010 to 450 000 t/a in 2018, with a compound annual growth rate of 12%. The capacity reached 800 000 t/a in 2019, among which PLA had 130 000 t/a, with Zhejiang Hisun Biomaterials and Anhui Fengyuan Group as main manufacturers. China’s large PBS/PBAT producers are Kingfa Technology and Xinjiang Blue Ridge Tunhe Sci. & Tech. The capacity of polyhydroxy fatty acid ester (PHA) was 15 000 t/a, the capacity of polymethylene-ethylene-carbonate (PPC) was 35 000 t/a, and the capacities of other biodegradable plastics were more than 100 000 t/a. The market started to see coal-based PGA products since 2020, which enjoy high degradation rate and low raw material cost. China’s PBAT capacity by 2019 reached 453 000 t/a, and the breakdown by manufacturer is shown in Table 1.
Market
China's biodegradable plastics market started late. However, on the gradual implementation of the policies banning and restricting plastics, the growth of demand for biodegradable plastics has been rising consistently, and the consumption has been growing rapidly.
The prices of biodegradable plastic products are also increasing since 2016, much higher than those of traditional plastics. The prices of different biodegradable plastics from 2014 to 2019 are shown in Table 2.
In the short term, the biodegradable plastics prices increase will slow down with the expansion of the capacity. In the long term, the biodegradable plastics prices will decrease with the diversification of raw materials and the progress in technology.
Development
1. Demand growth continues
Supported by government policies, China's biodegradable plastics demand might increase largely in the future. The vigorous demand for one-time biodegradable plastic products from express delivery, takeaway and hotel industries will further push up the consumption of biodegradable plastics, which is expected to be over one million tons in 2025. With the implementation of carbon neutrality measures and carbon peak measures, China's biodegradable plastics market will be on a rocket by 2050.
2. Capacity expansion continues
China’s biodegradable plastics capacity is expanding. According to statistics, there are 80 000 t/a PLA under construction and 1.2 million t/a PLA in planning. As for PBAT and PBS, there are 687 000 t/a under construction and 1.5 million t/a in planning. The domestic PBAT/PBS supply-demand balance will be changed soon after these capacities are launched.
As PBAT and PBS’s raw materials like terephthalic acid, adipic acid, succinic acid and 1,4-butanediol (BDO) are all petrochemicals, they have strong cost competitiveness and hence the fastest capacity expansion. According to public information, both Kingfa Technology and Shandong Ruifeng have a 60 000 t/a PBAT line. COFCO Biotechnology and Zhejiang Huafeng Spandex each has a plan of 300 000 t/a PBAT plan. Tongcheng New Materials has a project of 100 000 t/a, and Wanhua Chemical has planned a 60 000 t/a unit. All PBAT/PBS projects under construction and in plan are shown in Table 3.
Table 3 shows that China’s future PBAT/PBS capacity will be over 7 million t/a, with half of which from Xinjiang. Both raw materials supply and downstream players will be confronted with such a blowout in capacity expansion.
PBS capacities under construction total 265 000 t/a, from Gansu Mogao Juhe New Materials, Guangdong Kingfa Technology, Yingkou Kanghui Chemical, Anhui Sealong Biotechnology, Shandong Lianchuang Polymer, Chongqing Hongqingda Industry, and Xinjiang Wang Jing Long New Materials.
PGA, being non-toxic and harmless, is an ideal material as it can be completely degraded to carbon dioxide and water in one to three months. Meanwhile, being a good derivative, PGA can very well absorb the rapid growing coal-based ethylene glycol capacity.
3. PBAT project should pay attention to the matching of raw materials
By analyzing PBAT’s raw materials, we may find that adipic acid, succinic acid and PTA are sufficient, and only BDO might become short due to the restriction on the expansion of its raw material calcium carbide, as shown in Table 4.
According to statistics, new BDO capacities, as large as 6.5 million t/a, would not be able to satisfy the production of PBAT/PBS as most of the new BDO projects will not be launched until after 2023. Also, most of the new capacities are still calcium carbide routed. Under the influence of "double controls" policies, calcium carbide prices are likely to remain at highs on short supply and robust demand. The cost of PBAT/PBS hence will be increased. Therefore, the future PBAT/PBS capacity depends on the supply of BDO.
4. Enhance the R&D of biodegradable plastics technology
The future research and development of degradable plastics will mainly focus on following directions. 1) Develop on-time controllable environmental degradable plastics through molecular design research and formula improvement to suit different applications and environmental conditions; 2)Actively develop efficient and cost-effective photosensitizers, oxidizers, bio-initiators, degradation promoters and stabilizers to further improve the on-time controllability, rapid degradability and complete degradability; 3) Accelerate the research of biodegradable plastics, the filling blending or alloying technology of general plastics and starch, cellulose or inorganic materials, and the fully biodegradable plastics and natural materials coating lamination technology; 4)Explore and cultivate strains of bacteria that can degrade ordinary plastics, so that the widely used plastics can be easily degraded after use.
The market, facing the plastic restriction policies and promotion of degradable plastics from governments at all levels, has a strong demand for biodegradable plastics, which, however, is not satisfied by domestic capacity and production currently. The biodegradable plastics prices will be maintained at highs in the short term, leaving the industry good profits. From the perspective of technical maturity, raw material supply security and cost competitiveness, PBS/PBAT and PLA might maintain their rapid expansion, and PGA is likely to catch up with them with quick progress in technology, ample raw material supply and cost competitiveness. With the gradual maturity of degradable plastics modification technology, China’s degradable plastics will usher in new development opportunities.
