Glossary
Key terms in waste management, recycling, circular economy, and venture capital. A reference for founders, investors, and industry professionals.
A
Anaerobic Digestion (AD)
A biological process that breaks down organic waste in the absence of oxygen, producing biogas (methane and CO2) and digestate (nutrient-rich residue). AD is used to process food waste, agricultural waste, and sewage sludge. The biogas can be upgraded to renewable natural gas (RNG) for injection into natural gas pipelines.
B
Biochar
A stable, carbon-rich material produced by heating biomass in the absence of oxygen (pyrolysis). When applied to soil, biochar improves soil health, retains water, and sequesters carbon for 1,000+ years. Biochar production from waste biomass generates carbon removal credits.
Black Soldier Fly (BSF) Larvae
Insect larvae used in bioconversion to process organic waste into high-protein animal feed and nutrient-rich frass fertilizer. BSF facilities are 10x more land-efficient than soy protein production.
C
C&D Waste
Construction and demolition debris, including concrete, wood, metals, drywall, asphalt, and roofing materials. C&D waste is the largest waste stream in the US by weight at 600M+ tons annually.
Carbon Credit
A tradable certificate representing one metric ton of CO2 equivalent emissions avoided or removed. Waste management activities that reduce emissions (landfill gas capture, recycling, composting) can generate carbon credits.
Chemical Recycling
Processes that break down plastics into their chemical building blocks (monomers) for repolymerization into new, virgin-quality plastic. Includes depolymerization, pyrolysis, and solvolysis. Addresses plastics that cannot be mechanically recycled.
Circular Economy
An economic model that eliminates waste by keeping products and materials in use through design, reuse, repair, refurbishment, remanufacturing, and recycling. Contrasts with the linear 'take-make-dispose' model.
Contamination Rate
The percentage of non-target materials in a recycling stream. High contamination rates reduce the value of recyclables and can cause entire batches to be rejected. Residential recycling contamination rates average 15-25%.
Cullet
Crushed waste glass ready for re-melting in a glass furnace. Color-separated, contaminant-free cullet is the primary input for glass recycling. Contamination by ceramics or heat-resistant glass is the main quality challenge.
D
Depolymerization
Breaking down a polymer (plastic) into its constituent monomers through chemical or thermal processes. Depolymerization enables true plastic-to-plastic recycling by producing virgin-quality raw materials.
Devulcanization
Breaking the sulfur cross-links in vulcanized rubber to produce reclaimed rubber that can be re-vulcanized into new products. Traditional devulcanization degrades rubber quality; advanced methods (microwave, ultrasonic) preserve polymer properties.
Digestate
The solid and liquid residue remaining after anaerobic digestion of organic waste. Rich in nitrogen, phosphorus, and potassium, digestate is used as agricultural fertilizer.
E
E-Waste (Electronic Waste)
Discarded electronic devices and components including computers, smartphones, TVs, appliances, and circuit boards. The fastest-growing waste stream globally at 62M+ tons/year. Contains valuable precious metals (gold, palladium, platinum) and hazardous materials (lead, mercury, cadmium).
EPR (Extended Producer Responsibility)
A policy framework that makes producers financially responsible for the end-of-life management of their products and packaging. EPR shifts costs from municipalities to brands and creates funded mandates for recycling infrastructure.
F
Feedstock
The input waste material for a recycling or processing facility. Feedstock security (reliable, long-term supply) is the most important factor VCs evaluate in waste-tech investments.
Frass
Insect excrement and residual substrate from insect bioconversion facilities. Rich in nutrients and chitin, frass is sold as premium organic fertilizer.
G
Gasification
A thermal process that converts waste into synthetic gas (syngas) at high temperatures with limited oxygen. Syngas can be burned for energy or converted to liquid fuels and chemicals.
H
Hydrometallurgy
Using aqueous chemistry to extract metals from ores or waste materials. In battery recycling, hydrometallurgical processes dissolve battery materials in acid and selectively recover lithium, cobalt, nickel, and manganese. Offers higher recovery rates than pyrometallurgy.
L
LCFS (Low Carbon Fuel Standard)
California's program that requires transportation fuel providers to reduce the carbon intensity of their fuels. Generates tradable credits that significantly improve the economics of renewable natural gas and other waste-derived fuels.
Leachate
Liquid that percolates through landfill waste, picking up dissolved and suspended contaminants. Landfill leachate must be collected and treated to prevent groundwater contamination.
M
MOIC (Multiple on Invested Capital)
A venture capital metric measuring total returned value divided by total invested capital. A 3.0x MOIC means $3 returned for every $1 invested.
MRF (Material Recovery Facility)
A plant where recyclable materials are sorted, processed, and prepared for sale to end markets. MRFs use a combination of manual labor, mechanical screens, magnets, eddy current separators, optical sorters, and increasingly AI/robotic systems.
O
Ocean-Bound Plastic (OBP)
Plastic waste within 50 kilometers of a coastline in communities without adequate waste management infrastructure. OBP certification enables premium pricing for collected plastic (2-3x standard recycled plastic).
P
PFAS (Per- and Polyfluoroalkyl Substances)
A class of 12,000+ synthetic 'forever chemicals' with extremely stable carbon-fluorine bonds. Found in non-stick coatings, firefighting foam, food packaging, and waterproof textiles. Persistent in the environment and linked to health effects. EPA has set MCLs at 4 parts per trillion.
Plastic Credit
A tradable certificate representing the collection, recycling, or responsible disposal of one metric ton of plastic waste. Companies purchase credits to offset their plastic footprint. Market reached ~$400M in 2025.
PRO (Producer Responsibility Organization)
An industry-funded organization that collectively manages EPR compliance on behalf of producers. PROs hire recycling service providers, manage collection systems, and report to regulators.
Pyrolysis
Thermal decomposition of materials at elevated temperatures in the absence of oxygen. Produces bio-oil, syngas, and biochar from waste biomass, plastics, or tires.
Pyrometallurgy
Using high-temperature smelting to extract metals from ores or waste. In battery recycling, pyrometallurgical processes melt batteries to recover cobalt and nickel but typically lose lithium to slag.
R
Rare Earth Elements (REEs)
A group of 17 metallic elements critical for EV motors, wind turbines, electronics, and defense systems. Supply is concentrated in China (60% mining, 90% processing). Recycling from e-waste, coal ash, and magnets is a growing alternative.
RNG (Renewable Natural Gas)
Methane derived from organic waste sources (landfills, anaerobic digesters, wastewater treatment) that is purified to pipeline quality. Qualifies for federal and state renewable fuel credits.
T
Tipping Fee
The fee charged by a landfill, MRF, or processing facility to accept waste. Tipping fees vary widely by geography and waste type ($30-150/ton). They are a primary revenue source for many waste-tech companies.
TRL (Technology Readiness Level)
A 1-9 scale measuring the maturity of a technology. In waste-tech VC: Seed investments target TRL 4-5 (lab-proven), Series A targets TRL 6-7 (pilot scale), Series B targets TRL 8-9 (commercial scale).
W
Waste Hierarchy
The priority order for waste management: (1) Reduce, (2) Reuse, (3) Recycle, (4) Recovery (energy), (5) Disposal. Regulations and investment strategies should follow this hierarchy.
WEEE (Waste Electrical and Electronic Equipment)
The EU regulatory framework governing the collection, treatment, and recycling of electronic waste. The WEEE Directive sets collection and recovery targets for member states.
34 terms defined. Missing a term? Let us know.