“Lengiproneftechim” (the Company) (“Lengiprogaz” till 1974) was founded in June 1945. The first task the Company faced was participation in the design and construction of the household gas supply system to Leningrad city.

It took the Company and other involved design and construction companies no more than three years to put into operation the 1st section of box-type heaters in Kohtla-Yarve Plant and main gas pipeline Kohtla-Yarve – Leningrad - the 1st long distance shale gas line in the world - in October 1948.

At the end of 1940s – beginning of 1950s, Lengiprogaz service profile changed immensely. The Company started designing oil refineries: entire plants and separate process units. By the mid-50s, the Company acquired the leading position in the field of HC recovery from the catalytic reformer products.

Shale Gas Plant in Slantsy town was commissioned in 1952 based on the Company’s design. The Company designed a Gas-Generator Plant provided with 36 shaft-type gas generators, 3 box heater sections, household gas treatment units and numerous offsite facilities. Participation in construction and development of shale production plants showed that the Company engineers were able to deal with complex tasks at a very high engineering level. Eventually, the Decree of the USSR Council of Ministers dd. September 29, 1951 stated that “Lengiprogaz” was unbundled from “Giprogaztoprom” into a separate company and included into the 1st group enterprises that were directly subordinate to the Ministry of Oil Industry.

The 1st in the USSR Platinum Catalyst Reformer was built in Krasnodar Refinery in 1954 on the basis of Lengiprogaz design.

A strong demand for petroleum products in the North West region at that time necessitated a new Refinery to be built there. Lengiprogaz became the general designer of the new Refinery. It was decided to choose Kirishi town as a new construction site among all possible locations. The construction began in 1960. The Refinery design envisaged the Refinery products to be conforming to all worldwide standards. Kirishi Refinery showed the best performance rates among the 2nd generation refineries built in the period between 1955 and 1970. Lengiprogaz contributed a lot into construction and development of Kirishi Refinery and it was acknowledged by a number of government awards, medals of All-Soviet Union Exhibition of Economic Achievements, honorary diplomas and letters of rewards from the USSR Council of Ministers and State Committee for Construction, Architectural and Housing Policy (Gosstroy).

It took the Company less tan 20 years to enter the international market. Lengiprogaz engineers designed quite a number of process units in Bulgaria, Hungary, DPRK, India, Ethiopia, Turkey, Yugoslavia, Cuba, etc. The Units built and put into operation between 1964 and 1987 have been successfully run so far.

The design of the “eldest child” of oil refining industry in Belorussia – Polotsk (later named Novopolotsk) Refinery - started in 1964.

Between 1960s and 1970s, the Company initiated and launched a number of big projects for integrated oil processing units, such as LK-6U (Motor Oil Production Complex). Eight 6-8 MTA capacity integrated systems of LK-6U type were built and are still operated in RF, CIS and Baltic states.

In 1974, "Lengiprogaz" was renamed to “Leningrad State Design Institute for Oil Refining and Petrochemical Enterprises” - “Lengiproneftechim”.

The 1st integrated motor oil production unit LK-6U in Mozyr Refinery was commissioned in early August, 1975. LK-6U systems were put in operation in Kremenchug, Pavlodar and Mozyr (the 2nd unit) Refineries in 1978. Two LK-6U units were built in Mazeikiu Refinery (in 1980 and 1983), one LK-6U unit was built in each of Achinsk Refinery (1983) and Chimkent Refinery (in 1985).

Lengiproneftechim still continues the design work for Kirishi Refinery. LAB/LABS (feed for production of biodegradable detergents) production complex based on the licensed UOP process of paraffins dehydrogenation followed by benzene alkylation (handled by “Panador”) was being designed since 1989. This production complex was commissioned in 1996.

In 1995, in accordance with the privatization plans, the Institute was transformed into an open joint-stock company OJSC "Lengiproneftechim", and in June 2000 JSC "Lengiproneftechim".

Since 2000s, not only in our country, but also abroad, the name of LLC "Lengiproneftechim" has been gaining a reputation as the leading design organization in the Russian Federation in the field of oil and gas processing and petrochemicals, designing projects at the highest quality level. Accordingly, the client base of the Company has significantly expanded. New facilities are being put into operation based on the designs developed by the team of LLC "Lengiproneftechim". In 2012, AGO plus Visbracker Naphtha Hydrodewaxing Unit (L-24-10/2000) within the Deep Oil Conversion Plant at  LLC "KINEF". In 2013, facilities of the Start-up Complex of the Deep Oil Conversion Plant at LLC "KINEF". In 2015, Low-Temperature Isomerization Unit Complex Isomalk-2-LIN-800 at JSC "RNPK"  (Ryazan Refinery). In 2018, High-Octane Naphtha Components Production Complex at LLC "KINEF". This achievement was awarded by the Honorary Diploma of the Governor of Leningrad Region A. Drozdenko to the staff of LLC "Lengiproneftechim". In 2019, PJSC "TATNEFT" named after V.D. Shashin put into operation the "Oil Refining and Petrochemical Plants Complex. Facilities intended for production of motor gasolines and individual aromatic hydrocarbons”, which made it possible to start production of high-quality gasoline of AI-92, AI-95, AI-98 and AI-100 grades at JSC "TANECO". This achievement was acknowledged by diplomas, thanks from PJSC "TATNEFT" and gratitude from the President of the Republic of Tatarstan. In 2020-2021, thanks to Lengiproneftechim's Project "Construction of a New VGO Heater in Shop No. 01 of KGPTO", a Heavy Residue Processing Complex was successfully put into operation at JSC "TAIF-NK", which was noted in the Letter of Gratitude from the Client to the staff of the Company. In 2021, the Yaya Oil Refinery successfully commissioned the Combined Straight-Run Naphtha Processing Unit UK-1, which was also designed by the team of LLC "Lengiproneftechim". This project allowed the Customer to launch production of high-quality motor gasolines and was awarded the medal "For Business for the Sake of Creation" from the Governor of Kemerovo Region.

In February 2005, the Company was affiliated by the Oil Company PJSC “Surgutneftegaz” and became a Limited Liability Company abbreviated as LLC “Lengiproneftechim”.

In 2016, the joint project of LLC "Lengiproneftechim" and LLC "NPP Neftekhim" “Development of a domestic Catalytic Reforming Process with Continuous Catalyst Regeneration for production of High-Quality Motor Oils” became the winner of the Skolkovo Foundation competition and awarded the status of a national project from the Russian Ministry of Energy.

In the period from 2018 to 2022, LLC "Lengiproneftechim" developed the first domestic Catalytic Reforming Process with Continuous Catalyst Regeneration, which obtained 6 patents in the Russian Federation, 4 foreign PCT applications were filed, and construction of the corresponding unit at Ilsky Refinery was started.