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Industrial products: HARDNESS PLANTS :

Restoration of books

New prospectives 

for the restoration of books


New prospectives for the restoration of books.

Dilution system of products to remove the acid from the pages of old books.

In past centuries the needs of the population to be able to comminicate, making art and poetry were up. With the beginning of the industrial production of paper printing it is no longer arrested. The printing technique was completed, costs are lowered to make available the books for the population. Industrial production of paper sheets began alf of thel XIX century. For the sizing of the paper was used a combination based resin and alum (aluminum sulphate). The resin and aluminum combination produces sulfuric acid and acid materials. This acid has focused on the page and began the destruction of the pulp process. the avarage duration of the books that were printed with that method is 50 to 80 years, depending on the lenght of exposure to light, temperature, humidity and no least the industrial pollution. Before the industrial production of paper  iron gallustine was used. This substance (iron sulfate II) begins its oxidation process when you start to write the words. With this reaction creates the free sulfuric acid. This process is called Tintenfrass. With the acid the pages of old books melt and go powder.

Remove the acids from the pages is not difficult for our plantsi. Today we try to store documents, data and records of old books on a microfilmed or typing on the computer, but for the most rare and expensive books they are required rational methods of water based restoration , to save documents and books. The break up of the books you can stop when necessary measures are taken to eliminate, in special laboratories, the acid in the pages.

In order to carry out this procedure serves a large quantity of water with suitable characteristics reached by the addition of specific products. This chemical solutions extract the acid, creating an alkaline reserve for  the preservation long - termin.

The main problem for the restorers is to have available a large amount of "special" water at the right time for the processing. With a professional restoration can save books.



We thank the University Library of Tübingen for giving us permission to use the illustrations for our prospectus.






The new frontier to produce the hardened water is based on the combination of the water treatment plant to plant and added with suitable products. The water treatment plant (with cartridges of demineralization or reverse osmosis) water gives osmotic standard for the addition process with suitable products. The volume flow is very powerful, and in only 135 minutes, the plant produces 300 liters water with a hardness of 195 ° f with a pH value between 6 to 9. With the conventional method can be produced in 3 hours only 40 liters water with a hardness of only 65 ° f.


smart concept for the professional restoration, the system will convince you for its professionalism, compact design and ease of use. No longer you need to weigh each chemical .....


It 'also included in the optimal dosing system CO2 to reduce water costs. The capacity of the plant is scheduled for restorers who work with the dampening system, with diving tanks or that use special processing equipment, such restructuring of the plot of the sheets, or mixture of adhesives.


Said plant is the optimal solution for libraries and archives wishing water produced rationally at low cost.
Benefits: - 300 lters of solution eliminates the acid in 135 minutes - you can adjusts the pH value between 6 and 9  -optimal dosage of CO2 -no need to decant chemicals - long term storage - alkaline reserve up to  0,3%.

The addition system for clean water, desalinated with standardized quality.


Pretreatment                        Hardening

1. filter
2. divider of pipes
3. softening plant
4. limitent (hardness detector) 
5. activ carbon filter
6. high pressure pump
7. reverse osmosis membrane
8. programmer
9. softened water storage container
10.launch pump
11commands for the pressure

1. container production  (batch) 
2. value control pH
3. conductivity control
4. pump with switch (on/off) 
5. mineral cartridges
6. container of CO2 
7. blender of CO2

For a restoration takes about 1.000 liters of water monthly,we recommend the use of the hardening system AR100. The pretreatment is  carried out with a total  demineralization cartridge totale type  DESTILLO.

For more than  1.000 l/month see the type  AR200 or AR300 where the reverse osmosys plant has occurred.

Reverse osmosys works almost without maintenance and not consumes chemicals (as a demineralization plant), keeps all heavy metals, chlorine, organic pollution and other substances. The plant is controlled automatically. Osmotic water goes into a storage container (included in delivery), it is withdrawn automatically to obtain a suitable solution for the restoration of books. Downstream of the storage tank you can install a sterilization plant ray UV for removing possible microorganism that disturb the processing itself. The water is  pretreated and stored in the tank. From the same goes a closed circuit where you add CO2, calcium and  magnesium. During the process is oversee the Ph value and the conductivity (indicate on display). 



Technical data hardening for the  restoration of books

Hardening system AR100 with demineralization cartridge type DESTILLO, hardening plants AR200/AR300 in combination with a reverse osmosys plant.

The experience in field teaches us that: 
consumption until 1.000 l/month:     AR100 
consumption until 2.000 l/month:     AR200
consumption over 2.000 l/month:    AR300




hardening type


amount of water batch













AR 100






AR 200






AR 300









We reserve every technical change


Version 11/2015



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