Shaval's oil press uses a Hot Extraction Process to extract the maximum possible oil yield. The press can be adjusted from a cold press which is suitable to extract oil used for human consumption, to various degrees depending what type of oilseed is being pressed.
Once the seeds are fed into the kettle, they are heated and the oil is crushed out with the worm while the oil cake is ejected. The oil is then filtered with a cloth-filter and vacuum.
The oil cake that has been ejected is used as a valuable animal protein feed. Depending on how much oil is required in the oil cake, the cake can be pressed again to extract more of the last remaining oil.
In larger biodiesel plants where more oil is required rapidly to produce a higher daily biodiesel capacity, more oil presses are erected in series. This increases capacity whilst also allowing for maintenance during quieter periods without stopping production completely.
The filtered oil can be pumped into storage where it is available to be processed into biodiesel when necessary.
Shaval BioDiesel Process
Oil Pre-Treatment Vessel
The Shaval Oil Pre-Treatment Vessel is constructed from stainless steel and has a capacity of 1400 litres.
Once the oil has been filtered by the oil press, it is pumped from storage and has to be pre-treated before transestification in order to produce a high-quality biodiesel. This process consists of:
- Degumming of oil
- Neutralizing of oil
- Drying of oil
The oil pre-treatment is a vital step to ensure maximum biodiesel yield i.e.: oil to biodiesel ratio and to prevent the formation of soap.
The removal of Phosphorides (or gums) is essential to prevent the long-term blocking of injectors.
Every plant has a control panel where every step of the process is controlled with switches and valves. The control panel is mounted on a frame that also houses certain pumps, filters and other crucial equipment used in the biodiesel production line.
Shaval BioDiesel will install the control panel in a location that is convenient to operate 'on the ground', which is determined upon initial site visit.
The Methoxide Vessel is constructed from stainless steel. Alcohol and catalyst are first premixed in this vessel, before being pumped into the Reactor Vessel for transestification.
Special care must be taken when preparing Methoxide as these chemicals are highly flammable and toxic. Once the complete biodiesel process is complete however, the end-product has a Flash Point of over 120 degrees Celsius and is less toxic than table salt!
Transestification takes place in a 1400 litre vessel constructed from stainless steel. This is the easiest part of the process since the oil pre-treatment has taken place.
The Reactor Vessel is not round, but shaped in a hexagon. This shape ensures that the molecules are mixed more effectively during transestification in order to reduce time and ensure a complete reaction.
The Methoxide Vessel is also constructed in this shape to ensure that the alcohol and catalyst are properly mixed into methoxide before being pumped into the Reactor for the transestification process.
Each batch contains up to 1000 litres of biodiesel. One reaction can be completed per hour, which means that each production line can be extended to produce any quantity of biodiesel up to 24 000 litres per day, with the addition of settling vessels.
The Shaval Settling Vessels are constructed from stainless steel and have a capacity of 1400 litres. These vessels increase capacity by allowing the biodiesel and glycerol to separate, while leaving the Reactor Vessel available to make more batches of biodiesel.
The Washing Vessel can process up to 4000 litres of biodiesel at a time. In it, the final steps are performed to clean the biodiesel for use in an engine. This phase addresses some very crucial factors needed to make biodiesel of an adequate quality including the removal of excesses, impurities, water and sediment. The process consists of:
- Water washing
- Mixing of additives
- Ultra filtration
The Shaval BioDiesel process includes the mixing of specially developed additives used to reach the required specifications for engine warranties which include points like Oxidation Stability and Cold Filter Plugging Point (CFPP).
Because biodiesel is biodegradable, these additives prevent the growth of micro-bacteria, prolonging shelf life. The additives also allow the biodiesel to operate in colder temperatures. The amount of additives mixed into the biodiesel will determine how cold a temperature the biodiesel will tolerate without clouding or gelling. In South Africa, -4 degrees Celsius is required to make the SANS-1935 winter spec, but during cold spells in certain areas like Standerton, Bethlehem and Sutherland this CFPP spec is insufficient and the producer will sometimes need to produce his biodiesel to be capable of operating at far lower temperatures.
The advantage that small to medium-scale producers have who produce their own biodiesel, is that because they are producing biodiesel for their own use, they are in a position to know the exact climatic conditions on the ground and also how long the turn-around time is between production and consuming of the biodiesel.
When biodiesel is made for blending, it cannot be known to the producer exactly what climate the biodiesel will be used in and also how long it will take from production to the point where the biodiesel is finally used by the end-user. Therefore the only guideline available to producers for blending is the spec, while 'self-sufficiency' producers can regulate and vary the amount of additives they use in a 'real-world' situation to ensure that the biodiesel will always be adequate for the operating conditions, meeting the spec and also not to use an unnecessary excess of additives when not necessary and therefore save on cost.
Shaval BioDiesel provides an A to Z solution for every biodiesel requirement, including Delivery, Installation, all Piping, Manifolds and Valves needed to produce the requested capacity. The production line will be designed to fit into the local time and labour constraints, while also allowing for upgrading at a later stage- without making any of the existing equipment redundant.
Lab equipment for titration is also supplied along with the necessary scales, chemicals and instruction to conduct the tests as well as comprehensive training to operate the whole plant. Back-up service is also provided as well as a 1- Year Warranty and the first year's membership to the Southern African Biofuels Association.
Storage tanks can also be supplied upon request, but storage tanks and silos are generally cheaper and more easily arranged by the client directly. In many cases these already exist on site and can be utilized.
We now selling biodiesel plants which are powered by generators, using biodiesel as fuel for the generators.
Several finance institutions are already financing Shaval BioDiesel plants including Wesbank, ABSA, TF Finance and Rentworks.
In every case where a Shaval Biodiesel plant is erected, the savings from producing biodiesel (as opposed to the existing monthly expense of buying regular diesel) will always be more than sufficient to cover the monthly finance installment.
This means that whenever a plant is financed like a vehicle over 54 or 60 months, the savings alone will be higher than the monthly premium. Therefore every client is immediately in a positive cash flow position, and not only after the capital outlay has been fully paid.
When requested, the repayments can also be arranged in 6-month or 12-month balloon installments like a bakkie or tractor to provide an early break for the purchasing of feedstock in the easiest possible way.