Sustainable and Cost-Effective Cleaning with Solvents

Cleaning of structural components is now an essential requirement across numerous industries. Which financial, technical and personnel resources are necessary to meet these demands is decisively dependent on the selection of the cleaning agent. Depending on the degree of soiling, solvents represent a more economical and sustainable alternative here. Industrial structural component cleaning essentially serves the purpose of providing the cleaning required for subsequent processes such as coating, welding, adhesive bonding and assembly, or for permanently flawless production functionality. Therefore, defined cleaning specifications today are firmly part of structural component requirements such as dimensions and tolerances. Cleaning frequently takes place in wet chemical methods. To achieve the required result reliably, repeatedly and economically, a solution dedicated to chemistry, facilities, methods and material preparation is needed. For non-polar soiling such as processing oils, cleaning with solvents is often a more economical, more effective and more environmentally friendly alternative. Fully enclosed facilities in which the solvent is circulated enable safe use. Photo: DE_Loesemittelreinigung_1

Series-integrated distillation and filtration provide consistent cleaning quality and extended service life of the solvent. Photo: DE_Loesemittelreinigung_Filtration

Solvent or aqueous detergent – soiling is decisive. The dissolving power of the cleaning agent, which has decisive impact on quality, costs and time, is the key factor. Typically aqueous substances and solvents are used. In the selection of the appropriate solvent, the chemical principle "like dissolves like" serves as a guiding aid: Aqueous detergents are generally used for water-based (polar) soiling such as aqueous coolants and lubricating emulsions, salts, wear and other solid substances. Here it is advisable to clarify material compatibility and results achievable through cleaning tests. For non-polar soiling such as processing oils, greases, waxes and resins, solvent is generally the correct choice. Depending on the soiling to be cleaned, chlorinated hydrocarbons, non-halogenated hydrocarbons or modified alcohols represent the most suitable solution. The latter have lipophilic and hydrophilic properties and can therefore remove both non-polar and, to a certain extent, also polar soiling. Solvents have high material compatibility. Cleaning takes place without oxidation, discoloration, dulling or other effects on the material surface. Another advantage is rapid and complete drying, even in complex structural component areas such as blind holes and undercuts. The regular monitoring of properties such as detergent concentration, bath contamination, pH value and conductivity required for aqueous substances becomes unnecessary with solvent cleaning. Which agent is most suitable for the relevant cleaning task is best determined through cleaning tests. These tests can be conducted by the Ecoclean group at test centers worldwide and in cleaning facilities for aqueous substances and various solvents.

Effective Cleaning Through Integrated Preparation

Ecoclean offers fully enclosed facilities for solvent cleaning in which the substance is circulated. For this purpose, cleaning systems are equipped with integrated distillation apparatus for continuous and automatic solvent preparation and full-stream and bypass filtration. This prevents workers from coming into contact with the solvent and ensures consistent cleaning quality and extended service life of the substance. Operation of the facilities under full vacuum eliminates the need for additional explosion protection when using flammable solvents. Because solvent regeneration is the most energy-intensive process, the facilities are equipped with apparatus for recovering the heat generated during distillation. This heat is used to warm the solvent, thereby reducing energy requirements. Solvent cleaning facilities can be equipped with multiple tanks for precision cleaning often required for subsequent processes such as hardening, coating, soldering, welding and adhesive bonding, as well as for component protection.

An electropolished work chamber and optimized flow conditions ensure that dirt that could re-contaminate parts does not remain in the facility. For precision cleaning tasks and/or component protection, facilities can be equipped with multiple tanks. Each tank has its own solvent circulation. Large pipe diameters enable rapid filling and emptying of the work chamber. Photo: DE_Loesemittelreinigung_2_Tanks

After machining steps such as machining, grinding and coating, approximately 950,000 medical device parts are cleaned daily with modified alcohol in two-shift operation. Photo: DE_Loesemittelreinigung_Brasseler

Cleaning With Solvents – Often the Environmentally Friendly Alternative

Solvents are frequently viewed with environmental concern in industrial component cleaning. This concern was certainly justified in the open cleaning facilities formerly used. The REACH (Registration, Evaluation and Authorization of Chemicals) regulation also raised concerns about solvent use in industrial component cleaning. Despite the fact that non-halogenated hydrocarbons and modified alcohols were never discussed in this context. Because of these concerns, water-based cleaning systems are frequently used in oil-penetrating cleaning tasks. The consequence, not infrequently, is an expensive cleaning process with suboptimal results. When water consumption, disposal of contaminated wastewater and consumption of cleaning chemicals are factored in, solvent cleaning in most cases is not only cheaper but also the more environmentally friendly alternative. By switching from aqueous cleaning to solvent processes, the company achieves significantly better quality and saves approximately 7.5 million tons of water annually. Photo: DE_Loesemittelreinigung_SuperiorProd

Optimum Solution for Numerous Applications

Numerous implemented applications demonstrate that solvent cleaning effectively meets demands across many different industries. Medical device manufacturer Gebr. Brasseler GmbH & Co. KG uses Ecoclean EcoCBase P2 and Compact 70P facilities operated with modified alcohols to clean approximately 12,000 different component types made from hard metal, stainless steel, steel, ceramic and titanium. Approximately 950,000 parts are cleaned daily in two-shift operation during machining steps such as machining, grinding and coating. To safely remove various soiling such as processing oils and grinding residue, particles and chemicals from galvanizing, each facility is equipped with two immersion tanks for pre-cleaning and cleaning or purification. Steam degreasing and ultrasonic equipment ensure that the cleaning required for the next processing step is repeatable and efficient and that processing times are short. US-based Superior Products, LLC, which manufactures fittings, distribution pipes and structural components used in industrial, medical and special applications, replaced its aqueous cleaning with a Universal 81C hydrocarbon cleaning facility. This facility has three tanks for pre-cleaning and precision cleaning with component protection and is designed for multi-stage processes including immersion spray cleaning, ultrasonic cleaning, rinsing, steam degreasing and drying.

In doing so, the company not only achieves significantly better cleaning quality in a short time but also saves approximately 7.5 million tons of water annually.

Switzerland-based SFS intec AG manufactures cold-formed, deep-drawn and plastic injection-molded parts and structural assemblies for the automotive and supplier industries. To increase capacity, the company invested in an EcoCCore system. This solvent facility can be operated with both hydrocarbons and modified alcohols and has comprehensive standard equipment. The work chamber, designed as standard for cleaning baskets measuring 670 x 480 x 400 mm, offers one-third higher batch volume compared to conventional facilities. Maximum batch weight is 200 kg. This customer-designed facility features an assembly module with serial injection spray washing via ultrasound and a third immersion tank for steel part protection. The frequency-controlled volume flow can also be used simultaneously with filtration. Particles are thus removed in parallel with cleaning and cannot accumulate in the work chamber. Filtration takes place via a bag filter with integrated magnetic separator and wax filter. At UK-based ATP Industries Group, which repairs gearboxes, transition from labor and personnel-intensive aqueous cleaning with numerous manual interventions to fully automatic solvent cleaning processes has resulted in significantly higher product quality and efficiency.

The company decided to supply three EcoCCore standard facilities, each equipped with two immersion tanks and optionally ultrasound.

They work with non-halogenated hydrocarbons and use them for cleaning mechanical gearbox parts after disassembly, removing oils, greases, carbon and road soiling in the process. EcoCBase, operated with the same hydrocarbon, is used for mechatronic structural components. Economics, working conditions and sustainability improved significantly as a result of this change. The company thereby saves approximately 100,000 liters of fresh water annually and eliminates disposal of and cleaning chemical costs. All of this enabled the investment in solvent cleaning facilities to be realized significantly faster than planned. Through the EcoCCore work chamber, designed as series for dimensions up to 670 x 480 x 400 mm, SFS intec was able to double its processing capacity. Photo: DE_Loesemittelreinigung_SFS intec At ATP, gearbox parts are placed in defined positions in cleaning baskets after disassembly and automatically transported to the EcoCCore facilities, where an operator selects the appropriate cleaning program. Photo: DE_Loesemittelreinigung_ATP-Group Ümit Tekeli Regional Sales Manager Ecoclean GmbH