Open LoopClose Loop

In use 存量

Bound into hundreds of gigatonnes of concrete, asphalt, glass and reclaimed land

Where 分布

Buildings and roads; river and marine dredging hotspots across South & Southeast Asia

Loop 回路

Recycled aggregate roughly 5–10% globally; higher in a few EU states

Governance 治理

No global monitoring body; extraction largely unmeasured

• Renewable energy 能源Electric crushers, conveyors and haulage; local supply cuts diesel
• Recycled input 再生Demolition concrete and reclaimed asphalt back into structural mixes
• Process 工艺Manufactured sand from quarry fines and de-risked mine tailings
• Design change 设计Thinner slabs, void formers, post-tensioning — less volume per m²

The largest solid material flow on Earth is also the least governed.地球上最大的固体物质流,同时也是最缺乏治理的一条。

Sources [1] [12] [13]

In use 存量

The single largest human-made stock; concrete dominates the 1.1 Tt of anthropogenic mass

Where 分布

China ≈50% of output; most cement is used within a few hundred km of its kiln

Loop 回路

Clinker cannot be re-clinkered; rubble is mostly downcycled to road sub-base

Emissions 排放

≈2.4 Gt CO₂ — around 7–8% of global emissions

• Renewable energy 能源Electrified and hydrogen-ready kilns; but only ⅓ of the CO₂ is fuel
• Recycled input 再生Slag, fly ash, calcined clay, recycled concrete fines as clinker substitutes
• Process 工艺LC3 low-clinker cement (−40% CO₂); kiln CCS — Brevik captures 400 kt CO₂/yr
• Design change 设计Right-size structural sections; reuse existing frames (−30–50% material)

Two thirds of cement's CO₂ comes from limestone itself — clean electricity alone cannot fix it.水泥三分之二的碳排来自石灰石本身的分解,仅靠绿电无法解决。

Sources [2] [3] [7] [8] [20]

In use 存量

≈26–30 Gt standing — about half of it in buildings and infrastructure

Where 分布

China ≈54% of output; roughly 70% of the world's steel still starts in a blast furnace

Loop 回路

Scrap ≈30% of metallic input; end-of-life collection is high but quality is falling

Emissions 排放

≈2.6 Gt CO₂e — 7–8% of global emissions

• Renewable energy 能源Hydrogen direct reduction plus electric arc on renewable power
• Recycled input 再生Sorting and shredding that keeps copper contamination under ~0.1–0.2%
• Process 工艺Retire blast furnaces at end of campaign, not mid-life; molten-oxide electrolysis long-term
• Design change 设计Bolt rather than weld; reuse beams and columns; lighter structural grids

There is not enough scrap yet — the 2050 scrap pool is being built today.现在还没有足够的废钢:2050 年的废钢池,正在今天被建起来。

Sources [3] [4] [6] [21]

In use 存量

≈9–10 Gt ever produced; over 5 Gt now in landfill or the environment

Where 分布

Packaging ≈a third of demand; ≈6% of world oil use goes into polymers

Loop 回路

9% recycled, ~19% incinerated, ~50% landfilled, the rest mismanaged

Trajectory 趋势

Projected to roughly triple by 2060 on current policy

• Renewable energy 能源Electric steam crackers and renewable process heat
• Recycled input 再生Mechanical PET/HDPE loops; enzymatic depolymerisation for coloured PET
• Process 工艺Chemical recycling only where mechanical genuinely fails; feedstock substitution
• Design change 设计Mono-material packaging, no multilayer film, refill and reuse systems

The recycling rate is capped by design: multilayer film is unrecyclable on purpose.回收率的上限由设计决定——多层复合薄膜从设计上就无法回收。

Sources [9] [11]

In use 存量

Façades, windows and a circulating fleet of bottles and jars

Where 分布

Furnaces run continuously for 12–15 years; a rebuild is the only chance to change technology

Loop 回路

EU container collection ≈80%; global cullet use far lower; demolition flat glass mostly lost

Physics 物理

Glass is infinitely recyclable in principle — contamination, not chemistry, breaks the loop

• Renewable energy 能源Hybrid electric and oxy-fuel furnaces, up to ~80% electric melting
• Recycled input 再生Every 10% cullet saves roughly 3% energy and cuts CO₂ further
• Process 工艺Align decarbonisation capital with furnace rebuild dates
• Design change 设计Lightweighting, refillables, deposit-return, de-mountable glazing units

A glass plant can only decarbonise on its rebuild date — the constraint is the calendar, not the technology.玻璃厂只能在冷修重建时更换技术——瓶颈是日历,不是技术。

Sources [14] [3]

In use 存量

Wardrobes worldwide, against roughly 90 Mt of textile waste generated each year

Where 分布

Polyester ≈57% of fibre, cotton ≈20%; spinning and dyeing concentrated in Asia

Loop 回路

Recycled content ≈8%, almost all of it bottle-PET; fibre-to-fibre recycling under 1%

Trajectory 趋势

Heading toward ~160 Mt by 2030 unless volumes are addressed

• Renewable energy 能源Electrified dyeing, drying and steam in wet processing
• Recycled input 再生Textile-to-textile polyester and cellulosic regeneration at scale
• Process 工艺Low-water, low-temperature dyeing; separate collection now mandatory in the EU
• Design change 设计Mono-fibre garments, no elastane blends, durability, EPR fees that bite

Blends are the recycling problem — chemistry struggles to unmix what design mixed.混纺是回收的根本难题:设计混在一起的东西,化学很难再分开。

Sources [15]

In use 存量

≈1 Gt in buildings, vehicles, packaging and transmission lines

Where 分布

China ≈59% of primary output; coal-heavy grids dominate the footprint

Loop 回路

Recycling uses ~5% of the energy; collection is good, alloy mixing causes downcycling

Energy 能耗

≈14 MWh per tonne of primary metal; ≈1.1 Gt CO₂e total

• Renewable energy 能源Hydro and firmed renewables — electricity is ~60% of the footprint
• Recycled input 再生Alloy-specific sorting and closed-loop scrap contracts
• Process 工艺Inert anodes that release oxygen instead of CO₂ (ELYSIS)
• Design change 设计Mono-material assemblies, fewer coatings, mechanical joints over adhesives

Aluminium is stored electricity; recycling it recovers about 95% of that energy.铝是被储存起来的电力,回收可收回其中约 95% 的能量。

Sources [5] [16]

In use 存量

≈700–900 Mt in grids, buildings, motors and electronics

Where 分布

Chile, Peru, DR Congo; average ore grade has fallen to roughly 0.5–0.6%

Loop 回路

Secondary metal ≈30–35% of refined supply — the strongest everyday loop we have

Demand 需求

Up ~40–50% by 2040 in clean-energy scenarios

• Renewable energy 能源Renewable mine power, electric haulage, renewable-driven desalination
• Recycled input 再生Urban mining: retired grids, motors, demolition cable
• Process 工艺Higher recovery from tailings and low-grade ore; bioleaching
• Design change 设计Stop oversizing cable, separable windings, avoid copper-in-steel mixes

No electrification without copper — and no new copper without lower grades and more rock moved.没有铜就没有电气化;而新增的铜,意味着更低品位与更多被搬动的岩石。

Sources [2] [4] [21]

In use 存量

Mostly locked in stainless steel; battery nickel is the fastest-growing share

Where 分布

Indonesia over half of world supply; laterite processed on captive coal power

Loop 回路

Stainless scrap loop is mature; battery-nickel recovery is only now scaling

Footprint 足迹

Laterite routes can be several times the CO₂ of sulphide routes

• Renewable energy 能源Replace captive coal at industrial parks with renewables and grid links
• Recycled input 再生Stainless scrap plus black-mass nickel from spent batteries
• Process 工艺Better tailings management; efficient matte conversion instead of pig-iron routes
• Design change 设计Chemistry choice — high-nickel energy density versus LFP durability

Battery nickel's climate footprint is decided by Indonesian coal, not by cell chemistry.电池镍的碳足迹由印尼的煤电决定,而不是由电池化学决定。

Sources [2] [4]

In use 存量

NdFeB magnets in motors, wind turbines, hard drives, speakers, actuators

Where 分布

China ≈70% of mining and around 90% of separation and magnet manufacture

Loop 回路

Under 1% functionally recycled — magnets are glued in and shredded out of existence

Risk 风险

Concentration risk, not geological scarcity

• Renewable energy 能源Cleaner, renewable-powered separation outside single-country clusters
• Recycled input 再生Magnet-to-magnet recycling from motors, drives and turbine generators
• Process 工艺Solvent-reduced separation; thrifting dysprosium and terbium
• Design change 设计Bolted, extractable magnet assemblies — a glued magnet is a lost magnet

The bottleneck is not the ore. It is separation, magnet capacity — and the glue inside the motor.瓶颈不在矿石,而在分离能力、磁体产能——以及电机里的那一点胶。

Sources [2] [4]

In use 存量

Solder joints in essentially every circuit board on Earth; plus tinplate and chemicals

Where 分布

China, Indonesia, Myanmar, Peru, Bolivia; ≈half of demand is solder

Loop 回路

End-of-life recycling roughly 30%; secondary tin about a third of supply

Exposure 暴露

62 Mt of e-waste generated a year, only ~22% formally collected

• Renewable energy 能源Electrified smelting and refining; renewables at remote operations
• Recycled input 再生Solder and board recovery from formal e-waste channels
• Process 工艺Low-temperature solder alloys; cleaner artisanal supply chains
• Design change 设计De-solderable joints, socketed parts, genuine repairability

The most critical metal nobody names: 0.3 Mt of tin holds all of electronics together.最关键却最少被提起的金属:三十万吨锡,把全部电子产品连在一起。

Sources [2] [17] [18]

In use 存量

Batteries take roughly three quarters of demand; superalloys and catalysts the rest

Where 分布

DR Congo ≈70%+ of mine supply, with a significant artisanal share; refining led by China

Loop 回路

Among the highest end-of-life recycling rates of the battery metals, roughly 30%

Regulation 法规

EU floor of 16% recycled cobalt in new batteries from 2031, rising to 26% by 2036

• Renewable energy 能源Hydro-powered refining in the Congo–Zambia corridor
• Recycled input 再生Hydrometallurgy recovering over 95% of cobalt from black mass
• Process 工艺Thrifting and cobalt-free chemistries where performance allows
• Design change 设计Traceability to mine site; glue-free packs that can actually be opened

Cobalt's hardest problem is human, not technical.钴最难的问题是人的问题,而不是技术问题。

Sources [2] [19] [22]

In use 存量

EV packs and grid storage — the first mass retirement wave arrives from the mid-2030s

Where 分布

Australian spodemene, Chilean and Argentine brine, Chinese refining

Loop 回路

Under 1% functional recycling today; EU requires 80% lithium recovery by 2031

Demand 需求

Up to eight-fold by 2040 in net-zero pathways

• Renewable energy 能源Renewable heat for calcination and evaporation; electrified conversion
• Recycled input 再生Black-mass hydrometallurgy and direct cathode-to-cathode regeneration
• Process 工艺Direct lithium extraction — smaller land and water footprint than ponds
• Design change 设计Battery passports; packs and modules designed to be opened, not prised apart

Recycling cannot feed a market growing eightfold — but it can supply the market after growth stops.回收无法喂养八倍增长的市场,却能供养增长停止之后的市场。

Sources [2] [4] [19]

In use 存量

Around 210,000 t above ground — jewellery, vaults, a thin sliver in electronics

Where 分布

Grades near 1 g per tonne: roughly a tonne of rock moved for a gram of metal

Loop 回路

Recycling supplies roughly a quarter to a third of annual demand

Hidden stock 隐藏存量

A meaningful share of the world's gold sits in uncollected electronics

• Renewable energy 能源Renewable microgrids replacing diesel at remote mines
• Recycled input 再生Urban mining of circuit boards and connectors
• Process 工艺Cyanide-free leaching; mercury elimination in artisanal mining
• Design change 设计Thinner plating, recoverable contacts, take-back for small devices

Gold is the one metal we already treat as infinitely recyclable — because it is priced that way.黄金是唯一被当作可无限回收的金属——因为它的价格就是如此。

Sources [2] [18]