Ballast Tank Chem-23

During the operation, the fins & tubes of the main engine air cooler which become fouled with oil, grease, dust and carbonaceous deposit, which will affect cooler efficiency and damage the system.

RXSOL-54-1048-020 ( www.rxmarine.com/safe-acid-descalex-liquid-20-ltr ) is a powerful dissolving agent of calcium carbonate. Therefore, it is better to use RXSOL-54-1048-020  to do circulating cleaning at an early stage before the scales build up and block the tube, or regular cleaning is recommended as well. It is impossible to do a circulating cleaning when the tube is completely blocked.

It should be preferably be started on a clean system since it is formulated to prevent growth rather than remove existing growth of microorganism < bacteria , fungi , larvae etc.. ( EXISTING GROWTH  CAN BE CLEAN BY USING RXSOL-11-1008--DC / RXSOL-54-1008-SA  ) 

The best POINT of feeding is as early as possible in the system , preferably at the suction point of strainer , this will helps dispersion of solution in all parts of the sewater cooling system.
 

# Effectively control  MICROORGANISM GROWTH
# Economical , reduce down time cost , also doesn't require  any special monitoring
# Also control biological corrosion

Dechlorination 

When RO or NF membrane is used in the RO/NF process, the feed must be dechlorinated to prevent oxidation of the membrane. RO membranes have some chlorine tolerance before noticeable loss of salt rejection is observed. The first sign of chlorine attack on RO/NF membrane is loss of membrane flux followed by an increase in membrane flux and salt passage. Eventual degradation may occur after approximately 200–1,000 hours of exposure to 1 mg/L of free chlorine (200–1,000 ppm-h tolerance). The rate of chlorine attack depends on various feed water characteristics. Under alkaline pH conditions, chlorine attack is faster than at neutral or acidic pH. An acidic pH is preferred for better biocidal effect during chlorination. Chlorine attack is also faster at higher temperatures and higher concentrations of heavy metals (e.g., iron), that can catalyze membrane degradation. Since oxidation damage is not covered under warranty, Technical person always recommends removing residual free chlorine by pretreatment prior to exposure of the feed water to the membrane. Other oxidizing agents such as chlorine dioxide, hydrogen peroxide, ozone, and permanganate are capable of damaging RO/NF membranes also if not used properly. 

Residual free chlorine can be reduced to harmless chlorides by activated carbon or chemical reducing agents. An activated carbon bed is very effective in the dechlorination of RO feed water according to following reaction: 

C+2Cl2 +2H2O→4HCl+CO2 

Sodium metabisulfite (SMBS) is commonly used for removal of free chlorine and as a biostatic. Other chemical reducing agents exist (e.g., sulfur dioxide), but they are not as cost-effective as SMBS. 

When dissolved in water, sodium bisulfite (SBS) is formed from SMBS: Na2S2O5 + H2O → 2 NaHSO3 

SBS then reduces hypochlorous acid according to: 2NaHSO3 + 2HOCl → H2SO4 + 2HCl + Na2SO4 

In theory, 1.34 mg of sodium metabisulfite will remove 1.0 mg of free chlorine. In practice, however, 3.0 mg of sodium metabisulfite is normally used to remove 1.0 mg of chlorine. 

The SMBS should be of food-grade quality and free of impurities. SMBS should not be cobalt-activated. Solid sodium metabisulfite has a typical shelf life of 4–6 months under cool, dry storage conditions. In aqueous solutions, however, sodium bisulfite can oxidize readily when exposed to air. A typical solution life can vary with concentration as follows: 

Concentration (wt %)    Solution life

10                                   1 week

20                                   1 month

30                                   6 months

Although the dechlorination itself is rapid, good mixing is required to ensure completion. Static mixers are recommended. The recommended injection point is downstream of the cartridge filters in order to protect the filters by chlorine. In this case, the SMBS solution should be filtered through a separate cartridge before being injected into the RO feed. Dechlorinated water must not be stored in tanks. 

When RO/NF membranes are fouled with heavy metals such as Co and Cu, residual SBS (up to 30 ppm) partially converts to oxidants under the presence of excessive oxygen. When there is a heavy potential for metal fouling, SBS dosing amount control must be optimized and oxidation conditions of the concentrate must be monitored by an oxidation-reduction potential (ORP) meter. 

The absence of chlorine should be monitored using an oxidation-reduction potential (ORP) electrode downstream of the mixing line. 175 - 200 mV threshold readings of the ORP have been typically applied. The electrode signal shuts down the high pressure pump when chlorine is detected. 

Dichlor granules dissolve quickly in water. They can be added to the waters surface, pre-dissolved in a bucket of water or added via a chlorination system. The pH level of dichlor is very stable, which means there is no need to add pH-neutralizing chemicals.

Dichlor is typically sold in granular form. This provides a simple and convenient way to chlorinate pools and spas. Dichlor is completely soluble in water and does not generate insoluble solids. Also, dichlor does not contribute to scaling. Thus, the dichlor products are suitable for hard water. Dichlor is typically sold by the manufacturer as a granular product with free available chlorine content depending on which form is used (dihydrate or anhydrous). Dichlor is available with additives which may provide some additional benefit to the user. However, it is important to note that if additives are mixed with the product, the available chlorine will be less than 56% or 62%. The available chlorine content is provided on product labels.

Slip Barrier Polymer Coats HOLD BLOCK is a  Heavy Duty protective Solution for hold of vessels,  which carrying corrosive and / or messy cargos  such as sulphur salt petcock coal and concentrates. It can be easily removed with it

Recommendation Dose for smooth surface : 
for Sulphur, Salt, etc        100 Ltrs/Hold for HANDYMAX & 150 Ltrs/Hold for PANAMAX
& for Petcoke, Coal, etc   200 Ltrs/Hold for HANDYMAX & 250 Ltrs/Hold for PANAMAX

This materials can be use directly with low pressure machine or manually by garden spray pump. in general practice on smooth & clean surface  each drums of 210 ltrs covers 2000 to 2500 sq meter while on rough and rusted surface require more quantities of materials.