Green chemicals pave the way

Drilling and mining chemicals supplier and manufacturer Samchem is increasing its development of environment- friendly products, Samchem head of research and development Dr Rakhi Pathak tells Engineering News.

She says that the products have undergone testing and have attracted promising feedback.

Samchem’s range of environmental products include dust suppressants, which have been supplied to a number of companies, including Kumba Resources, Spoornet, De Beers and AngloGold Ashanti.

Road environment dust suppressants (Reds) are supplied for dusty areas, work sites and roads.

Environment management products suppress dust on conveyor belts, crushing plants and delivery points.

Reds, which reduces tyre and engine wear and tear, is a liquid that is sprayed onto unpaved roads to suppress dust and protect surfaces. It forms a hydrophobic surface layer, which, over time, requires less spraying.

Volumes of between 50 t and 100 t of Reds a month are supplied to South African and Australian companies, and potential exports to Holland are currently being pursued.

Reds is also used to reduce dust on agricultural crops to improve crop production, owing to difficulties associated with removing dust from crops.

New contracts at Sishen and Kumba Resources for the supply of Reds could mean contracts valued at R60-million a year.

The products are completely biodegradable.

Another environment-friendly product, Crackem, a nonexplosive agent, is used as a substitute for traditional explosives. Chemicals, which crack and break hard rocks in mining without the dangers of explosives, are poured in a drilled hole. This is safer than traditional explosives, says Pathak, owing to the absence of toxic fumes, the possibility of flying rocks and improved worker safety.

Certain chemicals, when mixed with water, can expand to three or four times their initial volume. Owing to this expansive strength, rocks break open and crack into smaller pieces. No specialised machines or technology is required for this application.

Pathak says that three important aspects must be considered when using the nonexplosive agent. These include the spacing between drilled holes and their depth, the operating environment temperatures and the duration of chemical use. For this reason, four grades of the chemical for differing temperatures are supplied.

Rock-cracking can take between two and three hours, if using highly concentrated chemical mixes, or between 18 hours and 24 hours when using lower chemical concentrations.

Environment management dust suppressants (EMDS), used for mine stockpiles were the first products developed in Samchem’s environment range, and is supplied to Kumba Resources.

Samchem also markets products that treat oil pollution at drilling and mine sites.

Remediation of land sites contaminated by oil spills and leaks takes place on site to contaminant depths of up to 500 mm. Deeper contami- nated areas are excavated in the form of beds or wind rows. Petrohydrocarbon sludges can be remediated using the same process.

Chemical mixtures are poured in sumps at ratios of 5 ℓ for every 1 000 ℓ of effluent, oxygenating and lifting suspend solids to the surface. This removes the petrohydrocarbon footprint from the ground sumps and drilling rigs.

Sumpkleen reduces the chemical oxygen demand in decomposed sump water, de-emulsifying polymers and oxidising petrohydro- carbons present.

FACILITY EXPANSION, PLANT UPGRADE AND LABORATORY FACELIFT
The company has upgraded and expanded its plant facility, in Alrode, to accommodate increasing demand.

The plant is also now able run for 24 hours, when necessary, and the installation of an auto- matic chemical production system is under way.

Samchem’s laboratory has also been upgraded with equipment for testing product biodegradability.

The laboratry equipment includes mud kits, extreme pressure lubricant testers, which measure chemical lubricity, mud rheometers, viscometers, which measure oil viscocity and rolling ovens to test the effect of varying temperatures on a chemical. A consistometer measures the gel and set times of cement and grouts.

In addition to product development, the laboratory is used as a technical service department to test product and water samples on behalf of clients. Once faulty product samples are tested, alternative solutions to the chemicals used are recommended.

CHEMICAL BIODEGRADABILITY
Pathak says that Samchem’s focus is constantly placed on developing environment-friendly products to comply with new laws in South Africa, which require that chemicals are not toxic to the environment, aquatic life or to humans.

The dilution concentrations at which chemicals are not toxic are provided for each product and all finished products are issued with a biodegradability report.

Biodegradable products are made by combining biodegradable raw materials. Although raw materials that are entirely non-toxic are not always available, toxicity is controlled by using minimum quantities of the toxic product. Additionally, other chemicals are added to enhance only those qualities required from a toxic product.

LONG-TERM GOALS
The chemicals company will focus on expanding and further developing its environment products portfolio, and hopes to venture into new markets, particularly in Africa.
Samchem, established in 1983, was acquired by listed Australian drilling products and ser- vices company Imdex, in 2005.

Imdex owns a number of distribution, ser- vice and equipment manufacturing companies for down-hole and directional drilling services in the UK, Sweden, Africa, Canada, Chile, Mexico and Australia.
Samchem supplies chemicals and products to the mining and drilling sectors as well as applications for contractors, blasting agents and in oil and gas exploration.

The company also manufactures drilling and mining chemicals, such as lubricants, greases, foams, and grouts. Chemicals, plasticisers, extruders and extrud- ing chemicals, which bind clay together by packing molecules for increased compressive strength, are also manufactured for the brick and tile industry.
All raw materials used in the chemical manu- facturing process, including surfactants, wetting agents and base oils, are bought from a number of local suppliers.

GROWTH
Since Samchem’s acquisition by Imdex, the company has tripled its revenue and experienced significant growth in its overseas exports. Its research and development, production and field services support have been improved and Samchem is recognised as a significant player in the mineral and mining exploration sector in Africa.