Bagasse is the name given to the crushed sugarcane after the cane juice is removed from it. Immense quantities of bagasse are generated in Louisiana (USA), Brazil, Indonesia and India. Though it has 40 % water content, it is still widely used as boiler fuel in the sugar industry. However, burning bagasse in its wet state significantly lowers the efficiency of the boilers used to raise steam. The KDS exhibits its best drying performance while processing wet fibrous substances like alfalfa hay, bagasse and deinking sludge. Limited testing has shown that the KDS uses only 1500 kilojoules of energy to remove 1 kg of water from bagasse. This is lower than the latent heat of water, because the KDS uses mechanical forces to dewater bagasse. Limited testing has shown that the KDS can dry 0.75 tph feed rate of bagasse from 44 % water content down to 21 % water content, with a total power consumption of 120 kW.

The product particle size can be adjusted from coarse fibers to fine powder. Much higher bagasse feed rates are possible if the grinding motor horsepower is adequate. It is also expected that the energy consumption per fed ton will become less, at higher feed rates. Alfalfa hay, a similar fibrous material, needs only 75 kWhr/ton grinding energy consumption. At such low drying energy consumption rates, the power consumption of the KDS will be much less than the gross increase in electric power production, when bagasse-fueled boilers are used for generating electric power. In other words, there will be a net increase in the thermal efficiency, which will pay for the extra cost of the drying equipment, i.e., the KDS Micronex™, in a few years time. More testing of bagasse in the KDS Micronex™ in Brazil is being planned.

Sludges from paper making and paper recycling (de-inking sludge) are generated in large quantities throughout North America. Currently common sludge management practices of land-filling and land-application are under increased environmental scrutiny and are becoming increasingly costly. The KDS Micronex™ can dewater deinking sludge and enable the separation of paper fiber from other paper components (i.e. kaolin clay). The paper fiber can be recovered for fuel or recycled as fiber. Kaolin clay can be recycled in the papermaking process or other industrial applications. The removal of clay also significantly increases the fuel value of and reduces the ash created during combustion. FASC’s joint venture company – Alternative Green Energy Systems has designed turn-key solutions using the KDS Micronex™ to recycle sludges from the pulp and paper industry.

Extensive independent testing of the KDS done in the U.K show that 900 kg/hr feed rate of deinking sludge can be dried down from 38 % moisture to 16 % with a total power consumption of only 90 kW and a water removal rate of 236 kg/hr. Thus,the specific power consumption was 100 kWhr for a metric ton of input material and 136 kWhr per ton of output product. The water removal energy was 381 kWhr/ton or 1373 kilojoules per kg of water removal., or 1.373 GJ/ton. It must be noted that the theoretical minimum energy for water removal is called the latent heat of water and equals about 2258 kilojoules per kg of water. In practice, conventional thermal dryers use up to 3800 kilojoules of energy to remove 1 kg of water, i.e., 3.8 GJ/ton. Thus, the KDS uses only 36 % of the energy that a conventional dryer uses in the form of heat. Assuming that electric power costs $0.06/KWhr and natural gas (the cheapest of all conventional dryer fuels) costs $8 per gigajoule (actual recent natural gas futures price in New York), the drying energy cost per ton of water removed is 0.06 x 381 = 22.86 dollars per ton of water removed in the KDS. In a conventional dryer, the cost would be 3.8 x 8 = 30.4 per ton of water removal. Thus, the KDS has a 25 % cost advantage over conventional dryers, assuming that the relative prices of electricity and natural gas stay the same. It must be emphasized that clay and fiber components of deinking sludge CANNOT be separated from the deinking sludge dried in a drum dryer.

In contrast, the KDS produces a fluffy, fibrous product which enables the clay to be separated from the residual fiber which then can be burned in boilers as fuel. The clay can be calcined and reused in the paper-making process. Similarly extensive testing done in Ontario, Canada with a local deinking sludge showed that deinking sludge can be dried at similar feed rates and power consumption from an initial water content of 50 % to a final water content of 15 %, i.e., water removal rate of 370 kg/hr with a total power consumption of 100 kW. This represents even better economics than in the U.K testing, i.e., 33 % cost advantage over a natural gas-fired dryer.

In North America, wood waste, unsuitable for timber or pulp can be a disposal problem for the forestry industry. Wood waste can be efficiently burnt and is a renewable energy source; but wet wood is often only marginally economic because up to 40% of the heat value in the wood is used to dry the moisture in the wood chips. The KDS Micronex™ technology is an alternative to traditional methods of drying wood. The KDS Micronex™ combines both the pulverizing and drying operations in one compact machine, simplifying the process. Furthermore, the system is tolerant of contaminants such as dirt and stones that can cause sparking and fires in hammer mills. While grinding spruce/pine/fir (SPF) hog fuel of 25 mm size and 14 % water content, the KDS consumes 150 kW for every ton per hour of product having a top size of 2 mm and median size of 600 microns. With 50 % moist SPF or hemlock wood chips, the energy consumption is 300 kWhr/ton. 135 kg/hr of water are removed when the grinding power consumption is 150 kW. SAWDUST: FASC has dried and ground wet sawdust from initial moisture of 48 % down to 15 % while also making a fine powder out of it. 185 kg/hr of such fine powder having a median particle size of 250 microns was produced with a grinding power consumption of 140 kW. This fine, dry powder was then utilized to make wood-plastic composite.

The KDS was leased as the equipment of choice because no separate dryer or heat source was necessary. Hammer-mills are unsuitable for such fine grinding. Attrition mills can be used but they require the feedstock to be first pre-processed in a hammer mill and their capacity is limited. A scientific paper by Holtzapple et al. reports that attrition mills have an energy requirement of 261 kWhr/ton (0.94 MJ/kg) to grind down to 850 microns and 656 kWhr/ton (2.36 MJ/kg) to grind down to 106 microns top size. This does not include the energy required for drying the wood. An economic analysis shows that in this particular case, the KDS and conventional technology are roughly comparable in terms of their energy cost. The KDS does have the advantage of requiring no heat input and combines the functions of both a conventional dryer and grinder. BARK: A test in which SPF bark was ground and dried in the KDS showed that 636 kg/hr of bark having 50 % water content could be ground and dried to produce 361 kg/hr of product having 12 % final moisture content and median particle diameter of 250 microns. The water removal rate was 277 kg/hr (twice that achievable with wood) and the total power consumption was 180 kW. Such fine grinding down to 250 microns median diameter is required if the bark powder is to be burned in a dust burner. At $0.06/kWhr electricity cost, the combined grinding and drying energy cost in the KDS was calculated to be $16.98 per metric ton.

The conventional technology to dry and grind wet wood-bark is a drum dryer, hammer mill and attrition mill combination. With $8/GJ dryer fuel cost and an energy consumption of 3.8 GJ per ton of water, the drying cost in a drum dryer would have been $8.42 per hour or $13.24 per metric ton of feed material. The grinding cost would have been $6.5 per hour or $10.21 per feed ton, assuming 300 kWhr/ton grinding energy requirement in the hammer mill and attrition mill [Ref: Holtzapple et al.]. Thus, with conventional technology, the total drying and grinding cost would have been $23.45 per feed ton. Thus, the KDS, in this case, has a 27 % cost advantage over conventional technology.

Sapropel, or silt of the freshwater reservoirs, is a modern geological sediment which is made of aquatic plants and animal remains combined with scraps of higher plants, pollen, sand, clay brought from the dry land and solutions of various inorganic substances. The chemical analysis shows that the structure of sapropel includes all necessary elements for plant nutrition that can not be found in any other fertilizer. Sapropel contains a significant amount of humus acids and their salts, resistant to biological cleaving which considerably enriches the humus fund of the soil the material supporter of its fertility. Sapropel algae is “mined” from lake bottoms and processed by KDS from 80% moisture to as low as 5%. The dried material is a high value soil amendment/fertilizer.

Sewage sludge, also called digested sludge or “bio solids” are created at wastewater treatment plants as water is processed and purified. Currently many municipalities are facing challenges to environmentally and economically dispose of wastewater treatment plant bio solids. The KDS Micronex™ can dewater bio solids to reduce their volume and the associated transportation and disposal costs. The KDS Micronex™ is certified by the US Environmental Protection agency for its ability to destroy pathogens including salmonella, e-coli, and fecal coliforms.

The dry powders produced by the KDS Micronex™ are suitable for land application or for use as a fuel source where they can replace fossil fuels. Extensive testing in British Columbia, Canada has shown that digested sludge containing 80 % water can be processed at the rate of 300 kg/hr and that the resulting product had only 10-13 % water content. The fecal coliform count was consistently reduced from over 4 million MPN/gram (Most Probable Number of fecal coliforms per gram) in the raw digested sludge to well under 1000 MPN/gram in the dried product. This means that the product from the KDS Micronex™ met Class A standards for biosolids, i.e., the KDS can convert Class B biosolids to Class A biosolids, which are much more valuable as fertilizer. The power consumption was 500 kWhr per metric ton of raw digested sludge.

A detailed economic analysis shows that the processing cost will be $80 per wet ton of digested sludge, including amortization, labor and power costs. In other words, the production cost of one bone-dry ton of product will be $400. According to a leading academic researcher, competing technologies that convert Class B to Class A biosolids have processing costs ranging from $400 to $800 per bone-dry ton. Thus, the economics of the KDS for this application are extremely competitive. While this sludge-derived fertilizer is still rather expensive to produce, it is environmental regulation which requires that wastewater sludge be rendered pathogen-free. Hence, wastewater sludge beneficiation is one of the best applications for the KDS Micronex™.

About half of the electricity generated in the United States comes from coal-fired power plants. In all large power plants, coal is dried and pulverized in a ball mill to under 75 microns (200 mesh) before being burned. The drier the coal, the higher the value for burning. Coal’s moisture content can vary widely from 5 to 50 %. Recent testing by FASC indicates that bituminous coal can be dried from 15 % to 4 % final moisture content and ground to a median diameter of 63 microns (230 mesh) at a production rate of 3 or 4 tons per hour. The grinding energy consumption of 30-40 kW hr/ton is competitive with that of small ball mills. Unlike ball mills, the KDS machine reuses that grinding energy to dry the coal, hence is actually more efficient. With the KDS Micronex™, it is possible to increase the value of lower grade coals which have limited use at present.

Though already recycled in large quantities, the value of recycled glass is generally low and the costs of transportation can make recycling uneconomical.Glass fragments introduced to the KDS system in pieces 2″ in diameter, or less, are ground at the rate of 1 – 1.5 tons per hour into a fine powder. The powder is smooth and fine to the touch, without sharp edges. The maximum particle size is about 150 microns and about half of the powder is below 45 microns. Even finer particle sizes have been achieved with the KDS system at lower feed rates. In one such test, 18 % of the glass powder, i.e., 200 lb/hr of output had a particle size of less than 1 micron. The grinding energy required was only 200 kW hr/ton. No other grinder can produce sub-micron glass powder in such large quantities while consuming so little energy. Such fine glass powder can command high prices as an industrial feedstock.

The total volume of animal manure (cow, hog, chicken, and horse) in the United States is approximately 130 times greater than that of human waste. Animal manure has a long tradition of use as an effective fertilizer. However, with modern intensive agricultural production, manure volumes can exceed the capacity of nearby croplands to absorb the nutrients in the manure. Numerous cases have been reported in the media of inappropriately spread manure contaminating both surface and groundwater and seriously affecting both human health and the environment.

The KDS System can reduce animal manures to a fine dry powder which is virtually free of both pathogens and offensive odors. In this dry state (approx. 10% moisture), the odor is significantly reduced, and the manure can be stored, efficiently transported, and sold as a fertilizer. The manure can be blended, at the time of production, with a variety of other minerals and chemicals for manufacture of custom fertilizers. Once processed, the manure can also be pelletized for easy application to farmlands. The key advantages of the KDS Micronex™ are the lower operating costs and small space requirements compared with conventional hammer mill and rotary drum dryer systems. FASC’s machine footprint is about 100 sq. feet which is about 1/5 the size of conventional systems. Conventional systems also require significantly more operating energy to dry manures compared to the KDS Micronex™. Dried manure and other biomass can also have a value as a fuel source. FASC and our joint-venture company Alternative Green Energy Systems has developed complete turn-key solutions to cleanly and cost effectively burn manure and generate “green” power.

Phosphates are the naturally occurring form of the element phosphorus, found in many phosphate minerals. In mineralogy and geology, phosphate refers to a rock or ore containing phosphate ions. Inorganic phosphates are mined to obtain phosphorus for use in agriculture and industry. The mineral is processed in the KDS with other materials to produce a high value fertilizer. Recent processing (3/2015) of phosphate with 80% water content and material up to 3 inches yielded 200-325 mesh (74 microns-44 microns) output material with 6% water content. The KDS used a max 115 amps at a 1.5 ton/hour output rate. Output tonnage could be raised to 4+ tons/hour.

Meat Packing plants produce a lot of waste, including bones, when animals are processed into saleable meat. Inedible meat trimmings from processing are called offal. Recent concerns about mad cow disease (BSE) have made it impossible to feed these wastes and offal to cattle. Land-filling of these wastes is also becoming more difficult.

Recent testing by FASC has proven that after some pre-processing, meat packing waste and offal can be converted by the KDS Micronex™ into fine, dry powders, which are almost completely bacteria-free. These wastes have to be first chopped into 3 cm bits and back-mixed with the resulting dry product before being fed into the KDS. When an initial quantity of dry product is not available, the process can be jump-started by feeding a 50:50 mixture of chopped meat waste plus grain or wood waste. The product can be used as fish food or even chicken feed, in some cases. When meat waste and grain are jointly ground and dried in the KDS to under 12 % moisture content, a nutritious product results. FASC’s earlier experiments with restaurant food waste and okara also led to similar conclusions.

Alfalfa is a very nutritious grass that is widely used as cattle feed. Often, alfalfa is used as hay and baled accordingly. It is also possible to pelletize alfalfa and feed it to cattle. Pelletizing requires that the alfalfa be ground and dried first. FASC’s testing has proven that the KDS S8 machine can grind alfalfa hay fibers of 25 cm length and 25-30 % water content into a fine powder of 3 mm top size, with a power consumpion of 75 kWhr/ton, while drying it down to 17 % water content. Thus, the KDS can replace 3 pieces of equipment – drum dryer, hammer mill and pneumatic conveyor. Further development work is being done to optimize the application of the KDS to alfalfa grinding.

The KDS Micronex™ excels in grinding soft rock minerals into fine particle size. Limestone, gypsum, zeolite (clinoptilolite), glacial clay, and other soft-rock minerals are all processed into fine, dry powders. Generally, the KDS Micronex™ grinds soft rock minerals to particle sizes of less than 75 microns (below 200 mesh) at production rates of more than 2-3 tons per hour. The 35-50 kW hr/ton energy consumption of the KDS Micronex™ is competitive with smaller horizontal ball mills that do not achieve any supplemental drying.

The KDS machine was selected by clients in California and Washington State for grinding “solution grade” limestone, phosphate rock, and/or gypsum. Solution grade fineness (less than 75 microns) is necessary when soil amendments are distributed to crops through irrigation systems. The KDS Micronex™ has been used to process glacial clay into a fine powder for use in health spas as a body treatment. The KDS machine is easily able to dry glacial clay from an initial moisture content of 10 % down to 1 % final moisture while simultaneously grinding it to below 100 microns (140 mesh).

The KDS System enables a completely unique method of extracting gold from quartzite rock. While quartzite is being ground in the KDS Micronex™, the heavy gold-rich particles tend to stay in the grinding chamber called the clam and the rest of the ore is pneumatically conveyed out of the KDS machine. Gold recoveries of up to 90 % and quartzite grinding rates of 2 tons per hour have been achieved. This method of gold extraction is potentially revolutionary for gold mining. Currently research is ongoing to commercialize this application.