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Lynn’s Letters from 2014


December 2014

November 2014

October 2014

June 2014

May 2014

February 2014







We now have our first Flexigester up and running in Malawi. John has returned home after spending a week in Namisu, the children’s village near Blantyre in Malawi, that is operated by Aquaid Lifeline, the UK charity based in Girton, Cambridge. He was there helping to install the Flexigester. Everything went really well. The crates containing the Flexigester arrived on the Thursday lunchtime and by the end of that day the trench for the digester had been marked out and dug. The next day saw the Flexigester, Pasteu tubes and soil donuts being erected and the start of the filling of the Flexigester with a mixture of water and cow muck. All that remained to do on the next morning was the connecting of the gas lines including a clear plastic tell tale so that we can see any pressure building in to system which indicates that gas is being produced and checking everything to make sure it was gas and liquid tight. It was all very exciting seeing it finally come to life and all built within three days compared with the months it normally takes to build and anaerobic digester.

Angus, who is in overall charge of all the Aquaid Lifeline projects in Malawi is going to monitor the temperatures, pressure and pH of the Flexigester for us so we have some really data.

Katie Anderson and Joe DeGabriele from WASTE, Netherlands who are running the trials programme in Malawi for the Red Cross, came to the village to visit the Flexigester on Monday and were very impressed with it, especially how quickly it had been erected. They are going to arrange to have testing and monitoring done on the digestate and pasteurisation system in the labs at Blantyre Polytechnic.

As well as working on the Flexigester John also found time to visit some of the other communities run by Aquaid Lifeline and to learn more about the way of life in Malawi. He also visited the school to give the gifts to the school children that Butyl Products had kindly donated.

We now need to wait 2-3 months for the biological treatment culture to become established .

28 February 2014

First Flexigester is operational

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10 February 2014

Things are getting really exciting here. As I write this our first Flexigester is winging its way to Malawi – quite literally. It is due to fly from Heathrow today.

We have had a hectic couple of weeks making sure that we had all the components built and taken down to Butyl Products Ltd in Billericay where they were fabricating the main digester, gas bags and Pasteu tubes. Everything then had to be assembled and tested to make sure that it was gas tight. As expected there were one or two slight problems but, with a bit of ingenuity and adaptation by SOWTech and Butyl Products staff, these were overcome. The Flexigester system was blown up to check for leaks and none were found. As you might expect this was a great photo opportunity for everyone (see attached).

The system then had to be deflated and the big jigsaw puzzle of packing everything into the smallest number of packing crates began. This was completed on Friday morning with three crates being used. There was a space at the top of the final crate so Theresa from Butyl Products rushed off to the local shops to buy some colouring books, pens and other gifts for the children at the orphanage.

John is due to fly out to Malawi next week to oversee the installation and commissioning of the digester system which will have hopefully cleared customs and be on site by then.

We would like to say a huge thanks to everyone who made this possible especially to our partner Butyl Products for their belief in us and for everything that they have done to make this venture possible. Without the help and commitment of all their staff this would not have been possible.

We would also like to thank RIPCO of Rotherham who donated their time free of charge to help design and develop the hard plastic elements of the system and for building them, to Effast and Polypipe who have donated free of charge the hard plastic materials for RIPCO to use, to Dawbarn for helping design and build the soil donuts and to you for all your support and good wishes. We could not have achieved all of this without you. Hopefully this will be the first of many.

Flexigester flies to Malawi

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20 February 2014

Things have started to get really exciting in Malawi. As you know the Flexigester was sent off to Malawi just over a week ago. It arrived at Lilongwe and cleared customs very quickly. It then had a journey of about 150 miles by road to Blantyre.

Once we knew it had cleared customs we went into final preparations for John to fly out to Malawi on Tuesday (arrived on Wednesday) to supervise the installation. One of his first jobs was to look at the site. In his words “Tree and hedge may need sorting” but “new loos good”.

The Flexigester was still in Blantyre so they had to be brought to Namisu by truck. The three crates were collected today and work has begun on site. After some tree felling the ground was cleared and the trench has been dug to put the digester into. Work has finished for the day and tomorrow the digester should be installed.

After all this time it's good to see everything coming together.

It’s arrived!

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7 October 2014

New Flexigester Model V10

Before the summer we were thinking about the focus of our marketing strategy and, as I said in my last Lynn's Letter, we decided to highlight the Flexigester as a Fertiliser Factory. Looking at this made us realise that the Flexigester we sent to Malawi was not the right tool for the subsistence farmers we were wanting to help. It was too complex to install and too expensive. So we have spent the summer designing and developing a new Flexigester – the model V10.

The Flexigester V10 is a butyl rubber bag with two feed input/output pipes and a gas out pipe at each end making the digester body symmetrical so it doesn't matter which way it is unrolled in the trench. This also eliminates the need for a feed turret as the in pipes can be connected directly to a pour-flush latrine and/or held open using the feed collar so waste can be poured directly in. Similarly, at the other end, one pipe can be connected directly to an irrigation system if required whilst the other acts as the overflow pipe.

The Flexigester V10 System is sent complete with the digester body, a gas receiver gas, a gas pressure regulator, feed collar, gas pipe and connectors. The really big news is that it all fits into a single crate and can be sent by TNT door to door virtually anywhere in the world for around £300-400.

Even the crate that we send it in has a use. We have produced a pvc lining for it so that can be used to collect the biofertiliser that is produced by the Flexigester.

We are hoping that this will be our “Model T Ford” and are now looking for partners who will take a Flexigester V10, use it and trial it for us and give us feedback on how it works.

5 May 2014

We have gas!

It's been a while since we installed our first Flexigester in Malawi and I thought you'd like to know how it's going over there. The big news is that the Flexigester has produced burnable gas they can use in the kitchens.

We have been getting regular updates from Angus the Aquaid Lifeline Manager who oversees the children's village in Namisu where the Flexigester is sited. As we expected it took a little while for the digester to settle down. The microbes in the digesters need to establish themselves as they start to breakdown the waste. Wastes from the kitchen, from the cows they keep on site and wastes direct from the latrines are regularly going into the Flexigester now.

The Flexigester then started to produce gas and the rubber body of the digester began to expand. One of the things that we fitted into the gas line from the digester was a U bend section of clear pipe filled with water. The rise in pressure in the gas line showed as the water levels in the U bend moved and gas bubbled through the water.

Then yesterday we got the news we had been waiting for. The first removable bag was filled with gas and it was combustible. They rigged up the gas line to a Bunsen burner and put it into the kitchen. They tested the burning gas by heating some water, watched by a crowd of onlookers. This is so exciting for us as well as them as the digester has reach this point faster than we had expected it to. Our next step is to design a cooking stove that is more suited to their needs than the current ones available on the market.

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16 June 2014

Flexigester Fertiliser Factory

We have been spending sometime recently debating the focus for our marketing strategy. Global food security is a big issue these days especially in low-income countries and we decided that we wanted to highlight use of the Flexigester as a local “fertiliser factory”. By producing a liquid fertiliser from the waste we were returning plant nutrients to the soil which can lead to an increase in crop yields. This thinking was reinforced on Friday 13 June when we attended a conference on Climate Change and Food Security organised by The Humanitarian Centre in Cambridge.

The keynote speakers were Jonathon Porritt, the environmentalist, and Dame Barbara Stocking, former CEO of Oxfam. They both spoke very well but some of the statistics they gave were frightening. One was that there needs to be 70% more food by 2050 to feed the worlds population but, at the moment, 35-45% of all the food grown is not used to provide nutrition. There are many reasons for this including food rotting due to inappropriate storage facilities, rejection by western supermarkets of less than perfect food, overbuying by consumers, food going out of date before it is sold etc.

Both Jonathon and Barbara spoke about having to get back to basics and to think long term rather than short term especially in the Global South – using local inputs to increase yields rather than relying of imports, to go back to mixed cropping rather than monoculture and needing to look after the soil. This was exactly where our thinking had taken us and so it was reassuring to hear it from such authoritative people.

As well as the main speakers there were a number of marketplace presentations including one given by John. The title of the presentation was  'How we are trying to “Stop soil wasting away”' in which he highlighted the advantages of treating waste and using it as fertiliser to return nutrients to the soil. He used the Flexigester in Malawi as a case study to illustrate the presentation. He also came up with a new byline:

“We need to feed the soil......if we expect it to feed the people”

The talk was well received and we made lots of interesting contacts which we are now following up.

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Following on from the production of the new Flexigester V10 system we have created a whole new set of marketing materials to promote it. We have an 8 page pdf giving details of the V10 and a pdf leaflet giving people information about how they can partner with us to install Flexigesters at suitable locations as pilot projects.

However the thing we are most excited about is a new website dedicated to Flexigester. You can find it at www.flexigester.com. It is a joint collaboration between Butyl Products Ltd and ourselves with Butyl Products taking the lead in the selling of Flexigester kits and SOWTech providing the technical support.

Flexigester.com contains lots of information about the system and, as a first for us, we have made some short videos and put them on the website via YouTube. One of them is a time lapse video of the installation of the Flexigester System at Namisu, Malawi. It was shot at 10 minute intervals over 3 days and really shows how quick and easy it was to install it.

The website has just gone live and over the next few weeks and months it will continue to grow with new pages being added to it.

This has been a really exciting venture for us as it's the first time we have a product that has the possibility of eventually being able to be sold off the website. We hope you take a look at the website as your feedback is always welcome.

15 October 2014

New Flexigester Website

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6 November 2014

Visit to India

John Mullett has just returned from a trip to India with Craig Ball from Butyl Products Ltd. They were invited to go by Dr Shanmugam who is a Principal Scientist at the Central Leather Research Institute in Chennai and the Lead Government Technical Adviser on Waste Management Technology to the Chennai Provincial Government. The Province of Chennai are looking to install 62 AD plants to be run on animal waste, hotel waste and waste from the local vegetable market.

John and Craig had a number of meetings with local government officials while they were there including Mr Vikram Kapur who is the Commissioner of the Corporation of Chennai and responsible for providing all the civic services in Chennai, Mr K. Skandan the Chairman of the Tamil Nadu Pollution Board of Control and Mr R. Kumar the Additional Chief Environmental Engineer of the Tamil Nadu Pollution Board of Control whose objective is to control, prevent and abate the pollution of streams, wells, land and atmosphere in the State of Tamil Nardu.

They also met with Mr P. Subramani, the Director of Enkem Engineers PVT. Ltd, a local engineering company. Mr Subramani's hope is to bring practical sanitation and waste treatment to the rural villages in Gujarat. This is no small feat as Gujarat is the size of Ghana with a population size equivalent to that of Italy with over half living in rural communities.

India's Prime Minister, Natendra Modi, launched a Clean India campaign on 2nd October so the timing of the visit was really good. The target is to have a Clean India by October 2019 which is the 150th anniversary of Gandhi’s birth. According to The Institute of Development Studies in the UK, India generates more than 150,000 tonnes of waste every day. There is a culture of dumping and burning the waste in the open in large cities leading to environmental and health problems.

Part of the campaign is to eliminate open defecation in India. This will be a huge challenge as over 60% of people who practise open defecation live in India. It is not only a question of providing toilets and treating the waste but also of changing people habits and mind sets. Open defecation not only has environmental impacts but also social, economic and health impacts; nearly half the children under 5 are stunted, 200,000 die each year due to diarrhoea, girls regularly miss school during menstruation as there is no where private for them to go, at night women are vulnerable to attacks, and the list goes on.

We are hoping that we can work with Mr Subramani and others like him in India to provide Flexigesters to these communities and do our part in Prime Minister Modi's Clean India campaign and to give people something that they want to use.

AD plant in Chennai, India SOWTech and Butyl Products meet with the Tamil Nadu Pollution Board of Control

AD plant in Chennai, India

​Left to right: Dr John Mullett, Mr R. Kumar, Dr Shanmugam, Craig Ball at the Tamil Nadu Pollution Board of Control

Site being marked out

Three days later the digester is fully installed

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1 December 2014

Flexigester goes to Uganda

As I write this our third Flexigester has started its journey to Africa. This time it is going to Paul Kyalimpa in Uganda.

Earlier this year John and I met Paul at a talk on “Sustainable Agriculture in Africa” at the Humanitarian Centre, Cambridge where he was with Ian Sanderson of Afrinspire (www.afrinspire.org.uk). Paul is a Ugandan agriculturalist having studied Sustainable Agriculture at Reading University. He works with a number of charities including Operation Agri and Afrinspire. For both of these charities he runs trainings for groups of 25 farmers all over Uganda in the practice of sustainable organic agriculture. He has an interest in anaerobic digestion and has been involved in building brick digesters including one on his home farm. His wife, who was with him in Cambridge, is using the biogas for cooking. John explained to him about the Flexigester and Paul expressed a desire to try one. He will be in a good position to assess the pros and cons of each system. This has now become possible thanks to the generosity of Butyl Products Ltd who have offered to sponsor some Flexigesters for demonstration purposes.

A call to Afrinspire established that, not only did Paul still want one but also, Afrinspire had space in a container that was going to Uganda. The container was being shipped by Tools with a Mission (TWAM; www.twam.co.uk) and was going the following week. A Flexigester V10 system was made, the manual updated and printed, and it was all packed up ready to start its long journey to Uganda via Ipswich.

As it's going by sea freight it will not arrive at its destination until February so we will have to wait some time before we have any more news about it.