In the previous chapter we understood the basic principles of engine design and fuel injection, as well as a number of the problems associated with running on bio-diesel, very few problems were evident from running on refined oils which meet the relevant standards.

Problems with using unrefined oils were numerous and included:

Contamination of the lubricating oil due to unreacted and partially combusted bio-diesel blowing past the piston rings, this is caused by the additional thickness of the unrefined or straight oils not being correctly atomised as it was injected into the engine.

Straight Vegetable Oil (SVO) contains glycerine and its derivatives; again poor atomisation of these glycerines causes the polymerisation of engine oils, and leads to heavy and rapid internal coking of the engines internal components.

SVO’s can be up to eight times thicker than commercially available diesel fuel, and cause excess strain and premature wear upon diesel engine injection components, and ancillary items such as the cam belts which drive the injection pump. Cam belts on Fourtrak models are extremely durable, but loads of up to eight times their intended design loading will cause them to snap, or strip the teeth off them.

Bio-diesels can cause problems by attacking rubber based fuel lines, and the internal O rings and seals of the injection pump itself, if this has been reconditioned using cheaper European components, which are fine for conventional diesel, but not bio diesels.

Winter starting on unrefined oils may be difficult due to it waxing; commercially available diesel contains a winterising package to prevent this down to a guaranteed
-15 degrees centigrade. All bio-oils with the exception of pure sunflower or rapeseed oils will freeze in as little as 0 degrees centigrade, depending upon its composition.

Using the used cooking oils cause many more substantial problems, these have been highlighted in the previous section.

Conclusions are, based upon the evidence, that no unrefined oils should be used in Daihatsu diesel engines irrespective of the fact that they are originally designed as “world” engines, and can run on wide ranging fuel qualities. These findings are backed up by many years of research, scientific findings, and studies undertaken into all aspects of running bio-diesels.

Much information, and much more misinformation is out there, having studied much of it, the only conclusions are that there are many cowboys out there waiting to provide this misinformation in an attempt to sell us something sub standard.
Very little is posted on the internet about the negatives, but I have access to many research documents on this subject, and will occasionally drop some of the findings in.

Refining of pure rapeseed or sunflower oil is the best option to providing the best fuels, but many of the other oils which in the unrefined state will cause many problems; may be used refined; as can other sources such as waste vegetable matter or even soya oils.

Refining can be undertaken with great success on a home basis, small scale local production, or on a larger scale; this assumes that the raw ingredients are available and you have access to the consumables. Many reputable and disreputable sources of supplies of these chemicals are available, but they all carry a health risk, reputable suppliers risks are minimal to negligible, disreputable suppliers supplies are downright dangerous, and a health hazard.

Many reputable suppliers of bio-diesel refining equipment will supply all the equipment; chemicals, analysing equipment, and technical support to allow anyone to home produce bio-diesel which meets relevant standards. Starter kits are available from around £1000 and will allow you to produce your own batches of diesel in around 6-8 hours.
Many disreputable sites will supply poor equipment, or show you how to manufacture this equipment from scrap materials, these are extremely dangerous and potentially fatal, as the chemicals used to refine raw oils are toxic, or highly flammable. I would not advocate building your own equipment, it is cheaper to buy a commercially available reactor, and know it is fully tested and compliant with all the legislation required by industry.

Commercial producers will have fully automated plants; these will be capable of handling huge quantities, and have to comply with Health & Safety legislation as well as environmental protection legislation, due to them being a place of work.

Almost all bio-diesel is produced using a process called base catalysed transesterification, and uses chemical reaction to achieve this. Chemicals used are generally sodium hydroxide (caustic soda), potassium hydroxide (potash), alcohol in the form of either methanol, or ethanol.
All these chemicals are available in powdered or liquid form, and they all carry significant health risks, dust is emitted from the powdered chemicals, and vapours are emitted from the liquid forms of these chemicals. Exposure to these fumes carries a significant health risk, they attack the central nervous system and can cause permanent damage, additional information, is available from the Health and Safety Executive web site and should be read.

Base oils are monitored and modified as necessary to provide the suitable base oil for the next phase; this is done in a variety of ways to suit the specific process, and to ensure the final quality of the bio-diesel.

The transesterification process is where an alcohol (methanol or ethanol) is mixed with a catalyst (sodium or potassium hydroxide) to dissolve the catalyst into the alcohol; this is them placed into a closes and sealed pressure chamber along with the vegetable oil. Heat is applied to just above the boiling point of the alcohol to speed up the reaction, and the system is sealed to prevent the loss of the alcohol, this causes the separation of the mixture into straight bio-diesel, and glycerine in around 6-8 hours. Free fatty acids are broken down, and the viscosity is reduced as the mixture is agitated during the refining.

Separation of the bio-diesel and the glycerine leaves us with the bio-diesel (methyl-ester) on the top, and the much heavier glycerine on the bottom, both are alcohol rich at this stage, the separated crude glycerine can now be drained off.

Removal of the excess alcohol can now be undertaken by flash evaporation, or in commercial applications, distillation; distillation means the alcohol can be stored and reused on the next batch.

Finally our bio-diesel can be washed gently using water, this removes any residual catalyst or soap residue from the glycerine, once washed we have complete reaction, removal of glycerine, removal of catalyst, no free fatty acids, and most importantly, lowered the viscosity to just above that of commercial diesel fuel. We are now left with a refined product called bio-diesel which is suitable for mixing with commercial diesel, or used neat in our Daihatsu engines.

This refined bio-diesel eliminates most of the problems highlighted earlier, and will only mean that we have to make slight adjustments to our servicing schedules to maintain the integrity and reliability of our engines, such as reducing the cam belt change from 60-50,000 miles, and changing our semi synthetic engine oil slightly more often.

Home production is relatively easy, as earlier described, but I must warn anyone of the dangers of making their own equipment, as described on many websites, the chemicals are dangerous, and so is the equipment. Ignore these sites.

Websites describing the home making of refining equipment advocate the use of such items as electric drills, these; and simple things such as switching on a light, or other electrical equipment will ignite the flammable fumes emitted by the alcohol (methanol or ethanol). Properly manufactured equipment will conform to the FLP regulations (flameproof) this means that all electrical equipment used will not produce a spark, and run cool enough, and be thermally protected, so as not to run hot enough to ignite these fumes. EWS; and other forum users have found sites advocating the use of electric drills to agitate the flammable mixture used in the refining process; in comparison, this is more lethal than lighting a match in a gas filled room, no one in their right minds would do this.
Results of an explosion would be dire, possibly fatal to anyone refining oils, and anyone such as neighbours, or children playing in the vicinity of the refining area, try explaining to your insurance company that you were refining fuel. Insurers would not pay out, leaving you with a huge bill for repairing your property, adjacent properties damaged, or personal injury claims for injuries from single or multiple injured persons. Simply put, you may lose your house, and any other assets you own in compensation and legal costs as well as repairing any damage caused.

So what about refining my own fuels at home, will I be safe if I purchase a reactor from a reputable company, well yes and no; having looked at 30 websites at random there is clearly a lot of sub standard equipment on the market. Of all the 30 random sites I have looked at, only one stood out, the company is called Green Fuels Ltd, they provide a properly designed system for home use called the Fuel Pod, this is a compact unit which even incorporates its own fuel filler nozzle. This unit is an upright unit which takes up little floor space, and minimises the risks of home refining to virtually nothing, fill the machine and when it has done its work, wheel it to your vehicle and insert the filler nozzle into your fuel tank.
Good design is about more than the equipment, it is about minimising the risk of handling chemicals, storage, and spillage of liquids, as well as disposal of the waste products, i.e. glycerine and contaminated water used for the final washing process. Green Fuels have sorted this problem for you, disposal of unrefined glycerine is a problem in small quantities, pharmaceutical and chemical companies will purchase this product, but only in large quantities, for refining into a suitable product for manufacturing soaps, make up, and medicines. Green Fuels are beginning a collection service for these small quantities of waste glycerine produced by home producers; this will give them sufficiently large quantities, large enough to sell to the various buyers. Water used for the final washing process has also been eliminated, they are now supplying a dry powder wash, this, eliminates the need to pay an approved and licensed waste disposal company to dispose of this contaminated waste water.

It must be emphasised that I have no connection in ANY way with Green Fuels Ltd, they were simply the best company out of a random sample of 30 companies I studied, there are other reputable companies supplying quality equipment and support services.

To get started you will need the reactor and chemicals, as well as a suitable location to refine your oil, you will also need the appropriate safety equipment to undertake the processing, required safety equipment may vary, depending upon the process used.
Supplying dealers will forward the details of the purchaser to Revenue and Customs, this is a legal requirement, they will be able to monitor the quantities of chemicals supplied to you by the various suppliers, and assess whether you are exceeding the limit for tax free fuel. Limits are at present, 2500 litres of tax free bio fuel per year, above this limit, you are bound to pay duty on the fuel produced, rates vary dependent upon fuel usage, rates for road going vehicles, are higher than rates for non road going vehicles, except boats. Boats have their own category of taxation.
Due to these varying rates, you are liable for keeping accurate records of ALL fuel you produce; this includes fuel you may dispose of due to it being a sub standard batch, and applies to individuals and companies alike. Revenue and Customs already know how much chemical is needed to produce a batch of fuel, and will check the supplying companies records for consumables purchased by an individual, and cross reference these with the quantities of fuel claimed to have been produced.
Remember that at the annual MOT, the vehicles mileage is entered onto the system, so the authorities do have a record of mileage covered by individual vehicles in one year.

Licences are required from the Environmental Protection Agency (EPA), these are for a PPL, or pollution prevention licence, this, is to ensure any waste products are disposed of in accordance with the current legislation. This license also sets out the legal requirements for the storage of chemicals, and the quantities which may be stored; this varies slightly due to individual circumstances. Effectively, this license ensures you have to comply with the Health and Safety at work legislation and all the environmental legislation, and ensure you are disposing of any waste materials correctly, and through licensed companies.
While there is nothing prohibitive in the licensing, it may mean work will have to be undertaken for the safe storage of chemicals by individuals; companies may also have to update their storage, and their respective company policies.

Individuals who are in social housing, or rented accommodation may be prohibited from producing bio-fuels at home; it would be prudent to check with your landlords before continuing. Many contracts may prevent certain aspects involved with producing fuels, such as the quantities stored, or the storage of hazardous chemicals, or flammable liquids at their property.

Insurance is another issue, some companies may raise your premiums for your property, others may not, but impose specifications for the equipment used in the processing of oils, and conditions on the storage of associated chemicals.

Legislation at the present time differentiates between private usage, and usage by companies, a check on Revenue and Customs web site is very unclear as to the position. Calling a contact at Revenue and Customs soon clarified the position; this is at the present time:

Company users can use one machine to produce 2500 litres per year, per vehicle; tax free, anything produced above this limit is taxable at the appropriate rate. Should a company have multiple diesel powered vehicles, they will need one machine per vehicle to produce 2500 litres of tax free bio-fuel; they cannot use one machine for multiple vehicles.

Private users can purchase one machine, and several people can use that one machine; co-operatives such as these are perfectly legal as long as each individual user keeps their own individual records of the fuel they produce and use.
Should four individuals share a machine, they are only allowed 2500 litres of tax free bio fuel each, per year; they cannot produce 10,000 litres from the machine, and one user uses 4,000 litres, while the others use 2,000 litres each, per year.

Many home producers have already have already purchased their equipment and gone into production, this production has evolved into a small local business supplying bio-fuel to the general public, in much the same was as your local petrol station. While this is perfectly legal, duty must be charged on this fuel, and paid to Revenue and Customs at the appropriate time; differing legislation also applies and must be adhered too.
Various legislation applies, this ranges from Weights and Measures, a division of your local authority to ensure all measures fuel sold is accurate, to the required legislation for the storage and handling of fuel. Anyone refining their own fuel should seek expert advice in this area before proceeding.

What happens to waste products such as glycerine; these small quantities may be collected by companies and stored until sufficiently large quantities are available to sell on, unrefined; or smaller quantities may be processed for sale. Smaller quantities are refined into a usable state by distillation; this means that once it is refined by this process; that smaller or independent producers of make up, soaps, or medicines may purchase it. This opens up the market to sell this waste product, and ensures that recycled local products become available; these are not transported hundreds of miles to central processing plants, refined, and transported again, to individual factories.

Finally; we must not forget that Bio-diesel has a storage life, unlike ordinary commercial diesel; this is a MAXIMUM of six months, many experts do not advocate storage of more than three months. In summary, do not go mad and mass produce bio-diesel from your new equipment and store it for long periods, produce smaller batches as it is needed.