Background of Art In course of processing of conventional rubber and which have conducted many until now, having some weaknesses. The weaknesses can earn to be explained as follows : j The first on rubber processing to yield raw materials for crumb rubber is the coagulation of field latex becomes coagula with the addition of acid or naturally that is let coagulate by itself. Acid as the above mentioned that is ordinary and many used as materials is formic acid, which for smallholders this is expensive enough. Coagulation of latex by formic acid or other acids or naturally, and then the coagula was kept by soaking in the water during one until two week, will cause the bacteria multiply fast because in the coagula contents of protein, carbohydrate, and the other, will destroy natural antioxidant in the coagula which in the form of protein and amino acids, and it also caused release of ion Cu++ (as a pro- oxidant) which initially tied by protein, as a result, the rubber is easy to be oxidized when it's dried, which is shown by the low of PRI (plasticity retention index) of field coagula especially which is coagulated naturally (Hasma & Alias, 1990). Beside damage the antioxidant existing in coagula/slab, the bacteria activity will generate putrid or malodour that is very sting in coagula since from field until crumb rubber factory. The putrid odour generated because of protein biodegradation becoming ammonia compound and sulphide

by bacteria. These putrid odours come from raw rubber materials storage, room of air hanging of blanket crepe (pre- drying) and dryer machine. This matter is very bothering the environment. To overcome the problem of malodour, various equipments have been tried, but its result still not satisfied yet. So also the things with result of raw materials rubber obtained still malodour.

The second problem arising out by using conventional jor this existing until now processing system is needing the air hanging of blanket crepe process (pre-drying) during 7 up to 14 days, because if directly processed, value of PRI will be very low. The air hanging of blanket crepe process amounting of hundreds thousand ton will disturb even desisting capital it and its processing also become longer again., Both the problem has to be immediately overcome to be able to reach ISO 14000 standard with the reference of environmental impact, which must be taken care of. Beside that, to be made by special consideration is the quality of product to be able to compete with other state, and efficiency of processing cost.

Based on of the description above can be taken'a conclusion that the usage of formic acid or other acids as coagulator or naturally in the crumb rubber processing is cannot prevent growth of bacteria of the rottener in coagula, and for formic acid price is expensive enough.

In processing of ribbed smoked sheet/RSS, the problem that is faced is the usage of formic acid as coagulant of latex, the need of a lot of rubber wood which many as firewood to yield smoke and dried, the difficulty to get consistency, of smoke concentration, the difficulty to get optimal smoking temperature and time, its smoke pollute environment, the duration time for smoking and drying (4-5 days), and the possibility incidence of burning danger.

For the processing of block rubber skim is malodour sting and value of PRI very low of coagula coming from skim latex that was coagulated by sulphate acid. The putrid odour arising out because of protein biodegradation that is done by

bacteria. The low PRI value caused by the bacteria activity that is damage the antioxidant The problems above, can overcome by using liquid smoke, which made of wastes of palm oil shell (kernel), rubber woodcutting, and coconut shell piece.

Liquid smoke as according to this time invention have some excellences and abilities: Can overcome and prevent growth of bacteria pest of antioxidant in the latex and coagula, Can overcome putrid odour which have happened in raw materials rubber, giving typical aroma smoke of delicious, Can coagulate field latex, Can improving the characteristic and physical type of vulcanised, Improving the value of PRI the rubber obtained, Shorting time for drying, Very good as a coagulator which its cheap price, Very good as a preservatives, Very good as a rottener antibacterial, Can give good brown colour, The concentration can be controlled, In drying with hot air, the temperature is easy to be controlled, shorting time process till become 3-4 hour and Environmental friendly.

Summary of the Invention This time invention especially aims for the processing of natural rubber (crumb rubber, ribbed smoked sheet/RSS, blqck skim rubber) by using liquid smoke. More specifically, such processing here is to give treatment at natural rubber at the time of coagulation of field latex, giving of colour, and preservation, by using liquid smoke system of invention this time.

This liquid smoke made of wastes of palm oil shell, rubber woodcutting and coconut shell piece.

In principle, in rubber processing, of crumb rubber, ribbed smoked sheet (RSS) and block skim rubber, as according to invention this time is with giving treatment in each

processing in the form of the usage coagulator, preservatives, antibacterial and antioxidant compounds, smoking process, in the form of liquid smoke which to be made of wastes of palm oil shell (kernel), rubber woodcutting and coconut shell pieces.

By using this rubber processing system for RSS production, as according to this invention can reduce drying time become only 3-4 hour, production time become only 1 day, friendly of environment and safe to the danger of burn. PRI value increase because of the antioxidant is not destroyed by bacteria activity in the form of protein biodegradation that there are in latex and coagula.

For the processing of crumb rubber, the three of liquid smoke type of palm oil shell, coconut shell pieces and rubber woodcutting can coagulate latex at pH 4,5, 4,7 and 4,9.

In processing of RSS, its pH 4,5, and in coagulation of skim latex its pH 4,7.

The yielded coagula has value of PRI higher compared to which is yielded by using formic acid although it have been soaked in water for 14 days, and processed directly without pre-drying. Blanket and crumbs that is soaked and sprayed by liquid smoke show the increasing of Po (early plasticity) and PRI that are high enough if compared to control. The malodour of rubber crumb and blanket has loosened and changed with smoke aroma after sprayed or soaked in liquid smoke. Become result of invention this time is addition, spraying and soaking with liquid smoke as according to invention this time with various pH, concentration and time treatment of coagulation of field latex, deodorizing to decay, improving value of PRI and eliminate pre-drying process in crumb rubber factory.

Brief Description of the Drawings Figure 1 is a flow diagram of crumb rubber processing of field coagula with formic acid or naturally become SIR 20 and sources of reek/putrid/malodour.

Figure 2 is a flow diagram of crumb rubber processing of field coagula with liquid smoke become SIR 20 and smoke aroma that happened without process pre-drying.

Figure 3 is a flow diagram crumb rubber processing field coagula with formic acid or naturally become SIR 20 with treatment of soaking/spraying of liquid smoke and without process pre-drying. <BR> <BR> <P>Figure 4 is a flow diagram of comparison of ribbed smoked<BR> sheet processing of normally, by using liquid smoke and liquid smoke combine with process of extruder, and baling and packing like crumb rubber.

Figure 5 is a flow diagram block skim rubber processing by using sulphate acid and using liquid smoke as a coagulant.

Detailed Description of Invention The usage of liquid smoke as coagulator of field latex in processing of crumb rubber The liquid smoke is a result of condensation of yielded smoke of wood pyrolyses at temperature 400-450°C. In result of compounds analysis which there are in liquid smoke for example 45 compound type of phenol, more than 70 type of compound carbonyl which consist of aldehyde and keton, 20 acids compound, 11 furan compound, 13 alcohol compound and ester, 13 lactones compound and 27 polycyclic hydrocarbon aromatic compound (Reiner Hamm, 1977). Acids in liquid smoke especially acetic acid will coagulate field latex. Phenol compound in liquid smoke have proven has antibacterial, antioxidant and antifungi (Wazyka & Karseno, 2000). Antibacterial will prevent grow and kill bacteria in latex and coagula, so that putrid odour will disappeared in coagula. Antioxidant compound will protect rubber particles of air oxidation at high temperature so that the PRI value is still high. Antifungi will prevent growth of fungi in the dry sheet. Compound of carbonyl in liquid smoke is functioned as a given of brown colour at final product of RSS. Mixture of compounds of phenol, carbonyl,

ester and alcohol will generate typical smoke aroma in liquid smoke.

Producing of liquid smoke of invention this time is easy enough and modestly because its combustion only using pressure stove, kerosene fuel, equipments in the form of combustion stove, pipe and condenser tube.

In figure 1 seen that since from the field have occurred protein biodegradation by bacteria in coagula (slab), causing value of PRI low and putrid odour. After came to the factory, protein biodegradation in coagula still continue so that the putrid odour continue on raw materials rubber storage, room of air hanging of blanket crepe (pre-drying) and dryer machine.

To prevent this putrid odour, coagulation of field latex by using liquid smoke (Figure 2). Odourless yielded coagula and can directly processed without pre-drying process although have been soaked in water during 14 day, and economical expense and time during 7 until 14 day that is eliminating time and cost for pre-drying of blanket crepe in number hundreds of thousand ton. This matter gives four benefits that are high value of Po and PRI, eliminating putrid odour, efficiency of processing cost, and also quicker production time.

Liquid smoke contains of acid compounds in it with pH 2 until 3 can coagulate latex at pH 4,5, 4,7 and 4,9 during 15 until 20 minutes. Coagula obtained smell smoke and do not occurred deterioration, this matter prove that liquid smoke can prevent growth of bacteria. Quality of technical specification of crumb rubber, characteristics vulcanisation and physical of vulcanite equal with formic acid and better compared to nature coagulation Soaking and spraying of liquid smoke to coagula, rubber crumb and blanket in crumb rubber factory.

To increase PRI value and to deodorize the malodour which is generated from coagula, blanket crepe and rubber crumb conducted by spraying or soaking with liquid smoke. Figure 3 showing that treatment of spraying or soaking with the liquid smoke can be done by part of raw materials rubber in the form of: 1) coagula 2) blanket 3) wet crumb and 4) dry crumb.

Soaking or spraying in all process sequence can be conducted at every one part or two part of raw rubber materials form above to strengthen its result. Soaking or spraying with concentration 5% until 20% during 5 until 15 minutes, can improve value of PRI and deodorize to decay changed with typical smoke aroma. After done by soaking or spraying at one of the raw rubber materials form the above, the process of pre-drying is not need.

Usage Of Liquid Smoke In Processing Of Ribbed Smoked Sheet (RSS) Figure 4 is comparison of flow diagram between normal processing of RSS, using liquid smoke as latex coagulant, and the combination between using liquid smoke as latex coagulant and final packing as crumb rubber. On figure 4 seen that in processing of normal RSS compared to liquid smoke as coagulant, coagulation of latex with formic acid changed with liquid smoke and at the same time function as giver brown colour and preservative in course of normal smoking process RSS normally, and drying process conducted by hot air in tunnel dryer. In treatment with this liquid smoke do not be needed by smoking (fumigation) process which is needing time 4-5 day but only 3-4 hour for drying with hot air, so that its process will finish during 1 day, and by using extruder machine for blending dried smoke sheet, then pressing with 60 tons press and packing like crumb rubber hence will be formed uniform bales in a short time so that easy to be transported.

Usage Of Liquid Smoke In Processing Of Block Skim Rubber Figure 5 showing flow diagram of processing of block skim rubber by using of sulphate acid and liquid smoke. Skim latex coagulated with sulphate acid will yield an putrid odour coagula because of protein biodegradation by bacteria become sulphide and ammonia, so that the PRI value will be very low because of the damage antioxidant in the form of protein and amino acids by bacteria activities. But with liquid smoke will be yielded coagula smelling smoke or neutral and value of PRI its high. This matter is caused by in liquid smoke contains compounds of antibacterial, antioxidant, and typical aroma.