What Castle Environmental does

Castle Environmental is a UK-based specialist hazardous and liquid waste treatment company operating three purpose-built aqueous treatment facilities located in Ilkeston (East Midlands, headquarters), Stoke-on-Trent (West Midlands), and Cardiff (South Wales). Founded in 1984, the company has more than 40 years of operating experience, processes approximately 200,000 tonnes of waste annually, and recycles 65% of all materials received on site. Castle serves enterprise customers including chemical manufacturers, energy from waste (EFW) plants, oil and gas refineries, industrial cleaning firms, commercial retailers requiring secure destruction, and third-party waste management companies. Notable reference customers include a UK chemical manufacturer for which Castle acts as sole contractor for up to 20,000 tonnes per annum of acidic waste, an oil and gas refinery receiving up to 200 tonnes per week of fluoride caustic waste, and an EFW plant processing approximately 4,000 tonnes per annum of bagged APCr.

The company's core technology is in-house aqueous (water-based) chemical treatment of liquids, sludges, powders, and solids, supported by three on-site laboratories at Ilkeston that perform pre-acceptance, acceptance, and post-treatment testing. Castle holds several specialist processing capabilities explicitly noted as avoided by most other UK treatment plants, including ammonia and amine solution processing (Ilkeston), sulphide oxidisation for refinery-type wastes (Cardiff), and treatment of highly concentrated and aggressive acids such as Hydrofluoric (HF) and Nitric (HNO3) at Stoke-on-Trent. A full barcode scanning and stock inventory system provides waste traceability from arrival to processing, and the company also operates a bespoke Secure Destruction and De-Packing Plant at Ilkeston for the destruction of retail-packed and high-value goods. Castle holds ISO 9001, ISO 14001, and ISO 45001 certifications, is a member of the Environmental Services Association (ESA) and the Chartered Institution of Wastes Management (CIWM), and is registered with the International Supplier Network (ISN) for oil and gas contractor compliance.

Castle operates a sales-led, direct-to-customer business model with no intermediaries, resellers, or digital self-serve channels. Revenue is generated through transaction fees based on waste type, volume, frequency, packaging, and processing complexity, with a quote-based engagement model. The company maintains a named sales team comprising a Sales Director, Technical Sales Manager, three Regional Sales Managers (North, Central & South), a TWM Sales Manager, and a New Business Sales Manager, supported by free waste audits as a demand-generation tool. The company trades as Castle Waste Services LTD and Castle Oils LTD, both private limited UK companies, with no external institutional investment, venture capital funding, M&A activity, or public listing disclosed. With 91 employees across three sites, Castle runs a lean operation in which directors are involved in day-to-day running.

Name

Castle Environmental

Legal name

Castle Environmental is the trading name of Castle Waste Services LTD and Castle Oils LTD

Website

https://castle-environmental.co.uk

Company type

Private

Founded year

1984

Operating status

Operating

Headcount range

101–250 employees

Short description

Castle Environmental is a UK-based specialist hazardous and liquid waste treatment company operating three aqueous treatment facilities in Ilkeston, Stoke-on-Trent, and Cardiff, processing 200,000 tonnes of waste annually for chemical, energy from waste, and oil and gas customers.

Ownership category

akta.pro rank

Product category

Hazardous Waste Management Services

NAICS

Hazardous Waste Treatment and Disposal (562211), Waste Treatment and Disposal (56221), Remediation and Other Waste Management Services (5629)

SIC

Hazardous Waste Management (4955), Refuse Systems (4953)

akta.pro primary industry

Hazardous Waste Management (Collection/Treatment/Disposal) (IMAIAFAI)

akta.pro secondary industries

Special Waste Disposal (Asbestos, Treated Wood, PFAS-impacted Residuals, Other Regulated Wastes) (EUAIACAK), Hazardous Waste Disposal (Secure Landfills, Deep-Well Injection) (EUAIAFAC)

Keywords

• Hazardous waste treatment
• Liquid waste disposal
• Waste recycling services
• Secure destruction services
• Industrial waste management

Headquarters

HQ city

Ilkeston

HQ country

United Kingdom

HQ region

Europe

Offices3 records

Markets served

GTM type

B2B

Offering type

Services

Cost components

Operations, Personnel, Infrastructure, Technology or R&D, Supply Chain

Revenue model

1. Waste Treatment and Disposal Services: Castle Environmental charges fees for the treatment, disposal, and recycling of hazardous and liquid waste. Services are delivered through three UK-based treatment facilities processing waste in-house. Revenue is generated from processing fees based on waste type, volume, and complexity, with customers including waste producers (industrial companies, chemical manufacturers, oil & gas refineries) and third-party waste management companies. The company also recycles 65% of processed materials, recovering value from waste streams.

Go-to-market motion1 record

Distribution channels2 records

Marketing channels6 records

Core offering

Castle Environmental operates three UK-based aqueous treatment facilities that receive, assess, treat, recycle, and dispose of hazardous and liquid waste (acids, alkalis, sludges, solids, powders, APCr, ammonia/amines, bulk effluents). The company also provides secure destruction and de-packing of retail-packed and high-value goods, and offers free waste audits as a technical advisory service.

Differentiator

Problem solved

Functional benefit

Products and services

• Hazardous Waste Treatment & Disposal End-to-end in-house reception, assessment, treatment and disposal of hazardous waste (acids, alkalis, sludges, solids, powders, chemical effluents, ammonia/amines) for industrial producers and third-party waste management companies across the UK. Treatment capacity is 200,000 tonnes per year across Ilkeston, Stoke-on-Trent and Cardiff.
• APCr Recycling Services Specialist recycling of Air Pollution Control Residues (Calcium Hydroxide and Sodium Carbonate based) in tanker and bagged formats, producing recycled concrete blocks that satisfy End of Waste criteria. Serves Energy from Waste plants and utilities producing APCr.
• Secure Destruction & De-Packing Robust and secure destruction and de-packaging of hazardous and non-hazardous retail-packed products and high-value goods, providing chain-of-custody documentation to prevent products from entering secondary markets. Targets commercial retailers and manufacturers.
• Waste Audits & Technical Consultations Free technical waste audits and consultations delivered by Castle's Technical Assessment team, providing accurate waste classification, regulatory compliance review and recommended treatment pathways for prospective and existing customers.

Quantifiable outcome

• 200,000 tonnes of waste treated annually
• +4 more outcomes

Named customers10 records

Segments6 records

Ideal customer profiles5 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature7 records

Partnerships

Four partnerships are on record, tiered core and minor.

• Environmental Services Association (ESA)coreStrategic or Co-development PartnerCastle Environmental is an active member of the ESA, the trade association for the UK waste management industry. Membership provides industry representation, access to best practices, regulatory engagement, and visibility within the hazardous waste sector.
• Chartered Institution of Wastes Management (CIWM)coreStrategic or Co-development PartnerCastle Environmental is a member of CIWM, the professional body for individuals and companies working in wastes management. CIWM membership supports professional development and industry standing.
• ISN (International Supplier Network)minorStrategic or Co-development PartnerCastle is a member contractor with ISN, which provides third-party contractor management services for safety, quality, and regulatory compliance verification, particularly for customers in high-hazard industries like oil and gas.
• Wildings StudiominorOthersWebsite design and art direction partner responsible for the Castle Environmental website redesign launched in July 2021.

Scale indicators5 records

Recent moves14 records

Expansion highlights5 records

Broad incumbents

• Clean Harbors: Clean Harbors is North America's largest hazardous waste services provider, offering treatment, disposal, and recycling across a broad industrial customer base. Comparable in core offering (industrial hazardous waste treatment at scale) but operating in a different geography with much greater scale.
• Suez Recycling and Recovery UK: Suez operates UK hazardous waste treatment, recycling, and recovery infrastructure as part of a global environmental services group. Overlaps with Castle on liquid and chemical waste customers but addresses a far broader waste management market.
• Remondis UK: Remondis is a German family-owned global waste management company with UK operations including hazardous waste treatment. Comparable in services offered but with substantially greater financial backing and geographic footprint.
• Biffa plc: Biffa is a UK-listed waste management major with hazardous waste capability alongside municipal, commercial, and recycling services. Competes for industrial hazardous waste volumes but at much larger scale and broader scope.
• Veolia UK (Hazardous Waste): Veolia is one of the largest UK environmental services operators with a substantial hazardous waste treatment business alongside municipal, water, and energy services. Competes with Castle on industrial hazardous waste accounts but as part of a much broader portfolio.
• FCC Environment UK: FCC Environment is the UK arm of the Spanish FCC Group, offering waste treatment, recycling, and disposal services including industrial/hazardous streams. Comparable in service breadth but operates as part of a much larger pan-European group.

Direct peers

• Grundon Waste Management: Grundon is a UK family-owned waste management operator with hazardous waste treatment capability and direct relationships with UK industrial customers. Highly comparable in scale, ownership profile, and breadth of liquid/solid hazardous waste treatment services.
• H W Martin Waste Ltd: H W Martin is a UK family-owned waste management group with hazardous waste collection, treatment, and disposal operations. Comparable to Castle as a privately held UK specialist with a similar customer mix of industrial and chemical generators.
• Tradebe UK: Tradebe is one of Europe's largest hazardous waste specialists with significant UK treatment operations. Closely comparable to Castle in its focus on industrial hazardous waste streams, chemical/petrochemical customers, and in-house treatment rather than transfer.
• Enva: Enva is an Ireland/UK hazardous and industrial waste specialist operating treatment facilities. Directly comparable in scope (hazardous liquids, sludges, solids), customer base (industrial generators), and recycling/diversion focus.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat5 records

Key risks6 records

Key highlights6 records

Customer concentration

• LinkedInlinkedin.com/company/castle-environmental
• Xx.com/castleenvr

Revenue estimate

Valuation estimate

Number of profiles

Profiles7 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Castle Environmental