Aim of the re­search pro­ject is the as­cer­tain­ment of eco­nom­i­cal and safe pro­cess con­di­tions of the pel­let jet spray tech­nique ap­plied for the re­moval of worn-out care film lay­ers from lay­ered floor­ings with­out dam­age and a se­cure re­moval of the formed dust by a vac­u­um tech­nique. Be­sides con­struc­tion­al data also rec­om­men­da­tions for pro­cess pa­ram­e­ters shall be de­vel­oped.

The first test se­ries were di­rect­ed to the op­ti­mi­sa­tion and adap­ta­tion of the cho­sen ap­pli­ance. Dew point tem­per­a­ture and flow of pres­surised air as well as of the abra­sion means had to be reg­u­lat­ed and con­trolled in a rea­son­able way.

The pre­dic­tion de­rived from pre­lim­i­nary short tests were con­firmed doc­u­ment­ing that the tech­nique can be used to re­move acrilate poly­mer and wax lay­ers on re­silient floor cov­er­ings. Ad­di­tion­al­ly it was found that in prin­ci­pal with few ex­cep­tion all floor­ing could be treat­ed by the dry ice jet tech­nique with­out rel­e­vant dam­age so that they can be re­gard­ed as un­re­strict­ed­ly clean­able. Ex­cep­tion are soft wood­en ma­te­ri­als and cer­tain stone floor­ing where abra­sion is ob­served.

Floor­ing sam­ples lay­ered with com­mer­cial floor care de­ter­gents based on waxes and poly­acrilates, but also those filmed with polyurethane dur­ing pro­duc­tion were treat­ed by a basic clean­ing pro­cess with . It is pos­si­ble to re­move worn-out poly­acrilates and waxes by con­ven­tion­al method, how­ev­er at the costs of high water de­mands and high eco­log­i­cal im­pact, the re­moval of polyurethane is im­pos­si­ble. The dry ice tech­nique led to a total re­moval of all of these lay­ers.

Fur­ther stud­ies have to im­prove the econ­o­my by in­creas­ing the amount of square me­ters cleaned per hour. To do this pa­ram­e­ter in­flu­ences like dis­tance jet/floor, jet ge­om­e­try, work­ing speed, de­gree of su­per­po­si­tion, vac­u­um re­moval of the formed dust have to be in­ves­ti­gat­ed and op­ti­mised.

Ac­knowl­edge­ments

The re­search pro­ject (AiF-RP-No. 11067) was sup­port­ed from the bud­get of the Fed­er­al Min­istry of Eco­nom­ic Af­fairs through the Ar­beits­ge­mein­schaft in­dus­trieller Forschungsvere­ini­gun­gen “Otto von Gu­er­icke” e.V. (AiF) (As­so­ci­a­tion of In­dus­tri­al Re­search Or­gan­i­sa­tions). We would like to thank all fund­ing or­gan­i­sa­tions.

The re­search re­port is avail­able on re­quest from FRT.